OBJECTIVES: Soldier performance in the Arctic depends on planning and training, protective equipment, and human physiological limits. The purpose of this review was to highlight the span of current research on enhancing soldier effectiveness in extreme cold and austere environments. METHODS: The practices of seasoned soldiers who train in the Arctic and cold-dwelling natives inform performance strategies. We provide examples of research and technology that build on these concepts. RESULTS: Examples of current performance research include evaluation of equipment and tactics such as the bioenergetics of load carriage over snow in Norwegian exercises; Canadian field monitoring of hand temperatures and freezing cold injuries for better protection of manual dexterity; and Dutch predictive modeling of cold-wet work tolerances. Healthy young men can respond to cold with a substantial thermogenic response based on US and Canadian studies on brown adipose tissue and other mechanisms of non-shivering thermogenesis; the potential advantage of greater fat insulation is offset in obese unfit subjects by a smaller thermogenic response. Current physiological studies are addressing previously unanswered problems of cold acclimation procedures, thermogenic enhancement and regulation, and modulation of sympathetic activation, all of which may further enhance cold survival and expand the performance envelope. CONCLUSION: There is an inseparable behavioral component to soldier performance in the Arctic, and even the best equipment does not benefit soldiers who have not trained in the actual environment. Training inexperienced soldiers to performance limits may be helped with personal monitoring technologies and predictive models.
Extreme Temperature Events (ETEs), including heatwaves, warm spells, cold waves and cold spells, have disastrous impacts on human health and ecosystems. The frequency, intensity, and duration of ETEs is projected to increase due to climate change. However, very little research has been done on ETEs in South Africa, and only a few attempts have been made to identify and examine trends. Currently, ten known publications have examined ETEs across South Africa, the majority of which use the South African Weather Service (SAWS) climate database as the primary source. The general findings indicate that the incidence and duration of extreme warm temperatures are increasing, while cold extremes are decreasing. However, inconstancies exist in the indices used to identify ETEs, selection of meteorological stations, study period, and statistical methods used to examine trends. We review the methodological approaches to define ETEs, the extreme temperature indices adopted, the selection of meteorological stations, study periods, data quality and homogeneity, statistical trend analysis, and results. From these, we propose an approximate number of stations to adequately portray temperature variability on a national and regional level. Finally, we reflect on projections of ETEs under current climate change conditions, and the implications of cold and warm ETEs in a South African context.
Urban parks play an essential role in urban settings; significantly contribute to the health of every age group person. Parks provide opportunities for families to connect with nature and breathe in the fresh air. Due to global climate change and increased urbanisation in the past few decades, extreme heat can be experienced in urban areas. Mental and physical health issues arise primarily due to a sedentary lifestyle in cities. Staying at parks for a longer duration could promote stress reduction and perceived physical health. The present study aims to assess the thermal comfort conditions at an urban park in the hot semi-arid climate(BSh) of Haryana, India. The present study investigated the outdoor thermal comfort range and thermal sensations of visitors at a park during the summer season using the onsite monitoring of the microclimate parameters and questionnaire survey in the hot-semi arid region of India. Thermal comfort indices, Physiological equivalent temperature (PET) and Universal Thermal Climate Index (UTCI) and Wet bulb globe temperature(WBGT) have been applied to investigate the outdoor thermal comfort conditions. The seven-point sensation scale has been used to record the visitors’ thermal sensations. The results indicated that:1) WBGT was found to be the most suitable index to investigate the OTC conditions. The neutral UTCI, PET, and WBGT ranged within 28.03 degrees C to 35.6 degrees C, 24.04 degrees C to 37.5 degrees C, and 23.5 degrees C to 26.1 degrees C, respectively. 2) The neutral PET ,UTCI, and WBGT were found to be 30.8 degrees C, 31.8 degrees C, and 24.8 degrees C, respectively.3) Dry bulb temperature is the most significant thermal comfort parameter affecting visitors’ thermal sensations, followed by mean radiant temperature.4) Thermal comfort indices were found to be most significantly affected by globe temperature. The study’s outcome could provide theoretical design reference to urban designers to develop new parks and existing parks, ultimately promoting public health. Copyright (c) 2022 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the F-EIR Conference 2021 on Environment Concerns and its Remediation: Materials Science
Climate change has significantly increased the frequency and intensity of human thermal stress, with relatively more severe impacts than those of pure temperature extremes. Despite its major threats to public health, limited studies have assessed spatiotemporal changes in human thermal stress in densely populated regions, like South Asia (SAS). The present study assessed spatiotemporal changes in human thermal stress characteristics in SAS, based on daily minimum, maximum, and mean Universal Thermal Climate Indices (i.e. UTCImin, UTCImax, and UTCImean) using the newly developed high-spatial-resolution database of the thermal-stress Indices over South and East Asia for the period 1981-2019. This study is the first of its kind to assess spatiotemporal changes in UTCI indices over the whole of SAS. The study also carried out extreme events analysis of the UTCI indices and explored their nexus with El Nino-Southern Oscillation (ENSO) index. Results revealed a significant increase in heat stress in SAS, with the highest human thermal stress in western Afghanistan, the Indo-Gangetic Plain, and southeastern, and central parts. The extreme event analysis showed that the study region is likely to observe more frequent and intense heat extremes in the coming decades. The correlation of UTCI indices with ENSO exhibited a robust positive coherence in southeastern and central India, southern Pakistan, and northwestern Afghanistan. The findings of the study are critical in understanding human thermal stress and adopting effective risk reduction strategies against heat extremes in SAS. To better understand the dynamic mechanism of thermal extremes, the study recommends a detailed investigation of the underlying drivers of UTCI variability in SAS.
The thermal adaptation of buildings and their residents is important in extreme cold climates for energy saving building design. A thermal measurement and a thermal comfort survey were conducted in traditional houses during the winter in the extreme cold climate of the Himalayan region of Nepal. Measurements were taken in 9 houses over 7 days to assess the thermal environment. Thermal comfort surveys were conducted over 4 days, and a total of 1,584 thermal responses were gathered from 36 residents. Passive heating effects were found in houses with thick brick walls and mud roofs. Residents of these houses were highly satisfied with the thermal environment, with 10.7 degrees C being the mean comfort temperature, which was related to the indoor temperature of the investigated indoor spaces. It can be concluded from these findings that people are well adapted to the thermal environment of traditional vernacular houses, as a result of which the comfort temperature is lower than the thermal comfort standards. Consequently, a significant amount of energy can be saved by passive building design and lowering the indoor temperature setting for heating. (C) 2020 The Author. Published by Elsevier B.V.
We provide the first estimates of the impacts of prenatal exposure to extreme temperatures on infant health at birth using the latest national birth data from 2009 to 2018 from all U.S. states. We consistently find that an additional day with mean temperature greater than 80°F or less than 10°F increases preterm births and low birthweight. Strikingly, the adverse effects are borne disproportionately by Black and Hispanic mothers, suggesting that the projected increase in extreme temperatures may further exacerbate the existing birth health disparities across different race/ethnicity groups. We also contribute by investigating the impact of deviations from the normal weather pattern, to identify the extreme weather events after accounting for the adaptation response. We find that prenatal exposure to extreme heat two standard deviations above county’s historic average induces preterm births and NICU admissions, particularly for mothers whose pregnancies overlap with summer months. These results are timely and policy relevant, considering the recent weather trends with rising temperatures and frequent extreme weather events.
This study is an assessment of the effects of outdoor air pollution and extreme weather events on the health of outdoor workers in Delhi, including auto rickshaw drivers, street vendors, and sweepers. To carry it out, a cross-sectional and perception-based epidemiological research design was used, and the primary tool used for data collection was a questionnaire. Two hundred twenty-eight people participated in the survey, and a pulmonary function test (PFT) was performed on 63 participants. Most of the respondents from different occupational groups complained about headaches/giddiness, nausea, and muscular cramps during extreme heat events due to the physically demanding nature of their jobs in the outdoor environment. Furthermore, autorickshaw drivers reported the highest prevalence of ophthalmic symptoms, such as eye redness (44%) and eye irritation (36%). In comparison, vendors reported a higher prevalence of headaches (43%) and eye redness (40%) due to increased exposure to vehicular emissions. Among sweepers, musculoskeletal problems like joint pain (40%), backache (38%), and shoulder pain (35%) were most prevalent due to occupation-related ergonomic factors. In addition, the majority of autorickshaw drivers (47%), vendors (47%), and sweepers (48%) considered that air quality had a severe impact on their health. PFT results showed that most respondents had restricted lung function. Binary logistic regression analysis showed that lung function impairment had a significant association with smoking (p = 0.023) and age (0.019). The odds ratio for smoking, which was around 4, indicated that respondents who smoked had a nearly four times greater risk of developing lung impairment. The study also highlighted the need for using personal protective equipment and developing guidelines to reduce their exposure level.
BACKGROUND: Exposure to high and low ambient temperatures is associated with morbidity and mortality across the globe. Most of these studies assessing the effects of non-optimum temperatures on health and have been conducted in the developed world, whereas in India, the limited evidence on ambient temperature and health risks and has focused mostly on the effects of heat waves. Here we quantify short term association between all temperatures and mortality in urban Pune, India. METHODS: We applied a time series regression model to derive temperature-mortality associations based on daily mean temperature and all-cause mortality records of Pune city from year January 2004 to December 2012. We estimated high and low temperature-mortality relationships by using standard time series quasi-Poisson regression in conjunction with a distributed lag non-linear model (DLNM). We calculated temperature attributable mortality fractions for total heat and total cold. FINDINGS: The analysis provides estimates of the total mortality burden attributable to ambient temperature. Overall, 6∙5% [95%CI 1.76-11∙43] of deaths registered in the observational period were attributed to non-optimal temperatures, cold effect was greater 5.72% [95%CI 0∙70-10∙06] than heat 0∙84% [0∙35-1∙34]. The gender stratified analysis revealed that the highest burden among men both for heat and cold. CONCLUSION: Non-optimal temperatures are associated with a substantial mortality burden. Our findings could benefit national, and local communities in developing preparedness and prevention strategies to reduce weather-related impacts immediately due to climate change.
In the Indian subcontinent, the annual average extreme weather events (EWEs) are reported to be increasing during the last few decades. The impact of increased EWEs on mortality has become a key issue in terms of minimizing it, even with the increasing population. In the present study, based on 50 years’ data (1970-2019) of India Meteorological Department, mortality rates of different EWEs viz., floods, tropical cyclones, heat waves, cold waves, lightning, etc. were analysed, both at the national and state level. The analysis was done based on different periods, i.e. annual, decadal and twenty-year slice periods. Various statistical analyses were carried out. Out of these EWEs, floods accounted for maximum mortality of 46.1%, followed by tropical cyclones with 28.6% mortality. Over the decades, despite a significant rise in EWEs (except for tropical cyclones), there has been a decrease in the mortality rate (mortalities per year per million population). The number of mortalities per event had a significant negative trend for heatwaves and floods, during the last 50 years. The total EWEs had a mortality rate of 3.86 during 1980-1999 and it reduced to 2.14 during 2000-2019. The mortality rate of tropical cyclones reduced by 94% in the past 20 years, whereas for heatwaves and lightning it increased by 62.2% and 52.8%, respectively. However, the change in mortality rate was not found to be statistically significant due to high year to year variability in mortality associated with floods, lightning, and tropical cyclones in the last two decades as compared to earlier decades. In India, among the major states, Odisha, Andhra Pradesh, Assam, Bihar, Kerala, and Maharashtra were found to be having maximum mortality rates due to EWEs in the last two decades and thus there is a need to consider these states with priority for developing disaster management action plans.
The aim of this study was to develop a database of historical cold-related mortality in Bangladesh using information obtained from online national newspapers and to analyze such data to understand the spatiotemporal distribution, demographic dynamics, and causes of deaths related to cold temperatures in winter. We prepared a comprehensive database containing information relating to the winter months (December to February) of 2009-2021 for the eight administrative divisions of Bangladesh and systematically removed redundant records. We found that 1249 people died in Bangladesh during this period due to cold and cold-related illnesses, with an average of 104.1 deaths per year. The maximum number of cold-related deaths (36.51%) occurred in the Rangpur Division. The numbers were much higher here than in the other divisions because Rangpur has the lowest average monthly air temperature during the winter months and the poorest socioeconomic conditions. The primary peak of cold-related mortality occurred during 21-31 December, when cold fronts from the Himalayas entered Bangladesh through the Rangpur Division in the north. A secondary peak occurred on 11-20 January each year. Our results also showed that most of the cold-related mortality cases occurred when the daily maximum temperature was lower than 21 °C. Demographically, the highest number of deaths was observed in children aged six years and under (50.68%), followed by senior citizens 65 years and above (20.42%). Fewer females died than males, but campfire burns were the primary cause of female deaths. Most mortality in Bangladesh was due to the cold (75.5%), cold-triggered illness (10.65%), and campfire burns (5.8%). The results of this research will assist policymakers in understanding the importance of taking necessary actions that protect vulnerable public health from cold-related hazards in Bangladesh.
Background: Personnel deployed at an altitude ranging from 9000 ft to 23,000 ft are exposed to sub-zero temperatures up to -40 degrees C. These conditions lead to the development of various cold injuries which presents in varying grades and severity. Aim: The aim of this study is to study the epidemiological trends and assess risk factors/conditions those are contributing to the development of cold weather injuries (CWI) at extreme cold climate in high altitude areas. Methodology: This is a retrospective, observational study on cold injury cases evacuated from the northern glaciers of India. The data were collected and tabulated in MS-Excel sheets, and analysis was done using percentage, mean, median, linear regression, and P value calculation. SPSS statistical analysis software version 23 was employed for generating the results. P < 0.05 was considered for statistically significant. Results: The annual incidence of cold injuries calculated for troops deployed at high altitude (>9000 feet) with extreme cold climate is 6.4/1000/year. The average duration of exposure for the development of CWI was found to be 4.85 h with a standard deviation = 2.88 h. Statistically significant association was found between the median temperatures and number of cold injury cases evacuated monthly with a strong negative coefficient of correlation (Pearson’s) value r = -0.8214, and P = 0.001063. No correlation was found between the severity of frostbites and duration of exposure as the coefficient of correlation r (Pearson’s) was weakly positive with a value of 0.19 and statistically not significant with P = 0.127. Conclusion: This study highlights the magnitude of problem, high risk zones, and predisposing activities. Statistical association has been drawn between altitude, temperature and duration of exposure with burden of cold injury. This study provides an insight with respect to associations and risk factors for the development of CWI, in Indian perspective and may be beneficial for better planning and preventive measures to reduce burden of CWI.
Extreme temperature events are linked to increased emergency department visits, hospitalizations, and mortality for individuals with behavioral health disorders (BHD). This study aims to characterize risk factors for concurrent temperature-related illness among BHD hospitalizations in New York State. Using data from the NYS Statewide and Planning Research and Cooperative System between 2005-2019, multivariate log binomial regression models were used in a population of BHD hospitalizations to estimate risk ratios (RR) for a concurrent heat-related (HRI) or cold-related illness (CRI). Dementia (RR 1.65; 95% CI:1.49, 1.83) and schizophrenia (RR 1.38; 95% CI:1.19, 1.60) were associated with an increased risk for HRI among BHD hospitalizations, while alcohol dependence (RR 2.10; 95% CI:1.99, 2.22), dementia (RR 1.52; 95% CI:1.44, 1.60), schizophrenia (RR 1.41; 95% CI:1.31, 1.52), and non-dependent drug/alcohol use (RR 1.20; 95% CI:1.15, 1.26) were associated with an increased risk of CRI among BHD hospitalizations. Risk factors for concurrent HRI among BHD hospitalizations include increasing age, male gender, non-Hispanic Black race, and medium hospital size. Risk factors for concurrent CRI among BHD hospitalizations include increasing age, male gender, non-Hispanic Black race, insurance payor, the presence of respiratory disease, and rural hospital location. This study adds to the literature by identifying dementia, schizophrenia, substance-use disorders, including alcohol dependence and non-dependent substance-use, and other sociodemographic factors as risk factors for a concurrent CRI in BHD hospitalizations.
The U-shaped association between health outcomes and ambient temperatures has been extensively investigated. However, such analyses cannot fully estimate the mortality burden of climate change because the features of the association (e.g., minimum mortality temperature) vary with human adaptation; thus, they are not generalizable to different locations. In this study, we assumed that humans could adapt to regular temperature variations; and thus examined the all-cause mortality attributable to temperature anomaly (TA), an indicator widely utilized in climate science to measure irregular temperature fluctuations, across 115 cities in the United States (US). We first used quasi-Poisson regressions to obtain the city-specific TA-mortality associations, then used meta-regression to pool these city-specific estimates. Finally, we calculated the number of TA-related deaths using the uniform pooled association, then compared it to the estimates from city-specific associations, which had been controlled for adaptation. Meta-regression showed a U-shaped TA-mortality association, centered at a TA near 0. According to the pooled association, 0.579 % (95 % confidence interval [CI]: 0.465-0.681 %), 0.394 % (95 % CI: 0.332-0.451 %), and 0.185 % (95 % CI: 0.107-0.254 %) of all-cause deaths were attributable to all anomalous temperatures (TA ≠ 0), anomalous heat (TA > 0), and anomalous cold (TA < 0), respectively. At the city level, heat-related deaths estimated from the pooled association were in good agreement with heat-related deaths estimated from the city-specific associations (R(2) = 0.84). However, the cold-related deaths estimated from the two methods showed a weaker correlation (R(2) = 0.07). Our findings suggest that TA constitutes a generalizable indicator that can uniformly evaluate deaths attributable to anomalous heat in distinct geographical locations.
We use temperature variation within narrowly defined geographic and demographic cells to show that exposure to extreme temperature increases the risk of maternal hospitalization during pregnancy. This effect is driven by emergency hospitalizations for various pregnancy complications, suggesting that it represents a deterioration in underlying maternal health rather than a change in women’s ability to access health care. The effect is larger for black women than for women of other races, suggesting that without significant adaptation, projected increases in extreme temperatures over the next century may further exacerbate racial disparities in maternal health.
There is scarcity of research examining the physiological and psychological effects of ultra-endurance racing on athletes in extreme conditions. The purpose of the current study was to identify common injury patterns and illness, profile mood states and sleep patterns and finally examine the relationships between mental toughness, sleep, mood and injury rates during a 120 mile, three-day Arctic ultra-marathon. Twelve participants (3 females, 9 males) with a mean age of 42 ± 5.35 yrs participated in the study. Mental toughness was measured using the MT18 questionnaire. Injuries were clinically assessed and recorded each day. Temperatures ranged from -20 to -6 degrees Celsius throughout the race. Sleep quantity and mood state were recorded using the BRUMS questionnaire. 10 out of the 12 participants experienced injuries; almost half of the participants had injuries that carried over a number of days. Mean sleep duration over the three days was 4.07 h, with an average of 0.78 injuries per day. Significant changes in mood were recorded across the three days, specifically a reduction in vigour (p = .029) and increase in fatigue (p = .014). Neither sleep quantity nor mental toughness was correlated with injury rate. Interestingly, sleep quantity was not related to changes in mood, as previously shown in ultra-marathons. Mental toughness had a moderate negative correlation (p < 0.01) with depression (-.623), reduced anger (-.616), confusion (-.558), increased vigour (.497) and tension (-.420) during the race. Success in this type of event involves significant psychological and physiological preparation to minimize the effects of sleep deprivation and avoidance of injuries.
This paper develops a biophilic wellbeing framework for positive indoor-outdoor connections in Arctic buildings to respond to occupants’ wellbeing and energy-efficiency requirements. Extreme cold weather and drastic photoperiods of Arctic climates could have adverse impacts on wellbeing and reduce connections with nature, i. e., identified as biophilia. Characteristics of positive relationships with extreme Arctic climatic stressors have not yet been comprehensively studied in terms of integrated wellbeing needs and energy efficiency requirements. This paper aims to articulate a fundamental wellbeing framework integrating thermal and photobiological needs with biophilic recommendations to characterize positive connections with Arctic climates for energy-efficient buildings. A scoping literature review is conducted to discuss occupants’ thermal and photobiological needs in relation to biophilic recommendations and Arctic climatic conditions. As a case study, shortcomings of existing building practices in Cambridge Bay, Nunavut, Canada, are studied regarding wellbeing, indoor-outdoor con-nections, and energy-efficiency needs. The proposed wellbeing framework for positive indoor-outdoor connec-tions in Arctic buildings integrates (i) thermal and (ii) photobiological indicators based on biophilic recommendations. The integrated wellbeing framework enables characterizing thermal and (photobiological) lighting adaptation scenarios responding to Arctic weather, daylighting, and photoperiods as well as energy efficiency. Intermediate spaces are also proposed as a prosing architectural solution to address the integrated wellbeing framework energy efficiency in arctic buildings. Overall, the proposed framework could help archi-tects, building designers, and stakeholders to develop further architectural solutions for positive, energy-efficient indoor-outdoor connections for Arctic buildings and occupants.
Global climate change has increased the risks of extreme weather-related disasters, leading to severe public health burdens. In February 2021, Winter Storm Uri brought severe cold to southern United States and caused unprecedented health and safety concerns. Residents in subsidized rental housing were among the most vulnerable to cold stress during such a cold storm. However, existing research on the assessment and mitigation of cold stress in underserved neighborhoods in warmer climate zones is limited, which results in the negligence of cold event preparedness and mitigation policies. Therefore, this study aims to assess the micrometeorological conditions and human cold stress in subsidized housing neighborhoods during the 2021 Winter Storm and determine the extent to which cold mitigation windbreak designs are effective in reducing cold stress. Field measurements, ENVI-met simulations, and biometeorological calculations were conducted to reconstruct the microclimate conditions and cold stress during the storm, and three cold-mitigation windbreak designs with varying foliage densities were evaluated. Results showed that the conditions were categorized as extreme cold stress for the majority of the day, but especially during nighttime. Areas close to the buildings were generally warmer, and the wind-blocking effects of a building decreased as the distance to the building increased. A moderately dense-foliage windbreak was the most effective in reducing wind speed and improving thermal comfort. Intentional environmental modifications to alter wind velocity and disaster relief programs that provide emergency clothing supplies during power outage may be beneficial to these underserved communities.
BACKGROUND: Acute coronary syndrome (ACS) is affected by several weather conditions. Studies from different geographical locations have yielded mixed results regarding the outcomes of patients presenting with ACS during snowy days, and we aim to report the Cleveland Clinic experience. METHODS: Patients who presented with an ACS and underwent percutaneous coronary intervention (PCI) from July 1, 2009 to September 30, 2017 were divided into ST-segment elevation myocardial infarction (STEMI), and non-ST segment elevation ACS (NSTE-ACS). According to snowy day arrival, we compared in-hospital mortality, culprit lesion anatomy, and door-to-balloon (DTB) time (in STEMI patients). Findings were confirmed in propensity-score matched cohorts. RESULTS: A total of 6878 patients were included: 1608 patients with STEMI (139 snowy-day vs 1469 non-snowy day PCIs) and 5270 NSTE-ACS (419 snowy-day vs 4851 non-snowy day PCIs). Right coronary artery territories accounted for most of the stented culprit lesions in all STEMI and NSTE-ACS snowy-day PCIs. While left anterior descending artery lesions were predominant in NSTE-ACS non-snowy day PCIs. There was no difference in in-hospital mortality between the snowy-day vs non-snowy day groups (4.3% vs 4.5% in the STEMI group [P=.92] and 1.2% vs 1.7% in the NSTE-ACS group [P=41]). In STEMI patients, mean DTB times were similar (43 ± 55.1 minutes vs 46.7 ± 59.6 minutes; P=.61), which remained true after hours, during weekends and holidays. Outcomes were similar in propensity-score matched cohorts. CONCLUSION: At our institution, snowy days do not seem to affect in-patient mortality. In STEMI patients, DTB times were similar in those who underwent PCI regardless of the snowfall.
Health researchers have examined the physiological impacts of extreme air temperature on the human body. Yet, the mental health impacts of temperature have been understudied. Research has shown that the environment can create circumstances that exacerbate mental health issues. This may be particularly challenging for some of the fastest growing cities, located in hot, dry climates. Given the theoretical relationship between air temperature and mental health, we seek to measure the association between temperature and schizophrenia hospital admissions in an arid urban climate and quantify the associated public health burden. We collected 86,672 hospitalization records for schizophrenia from 2006 to 2014 in Maricopa County, Arizona, USA. Using a distributed lag non-linear model (DLNM), we tested for a statistical association between temperature and schizophrenia hospital admissions after controlling for year, season, weekends, and holidays. We calculated the cumulative attributable risk of nighttime temperature on schizophrenia for the entire dataset as well as among demographic subgroups. The relative risk of schizophrenia hospital admissions increased with both high and low temperatures. Statistical models using daily minimum temperature were more strongly associated with hospitalization than those using mean or maximum. Schizophrenia hospital admissions increased on days with minimum temperatures above 30 °C and below 3 °C, with some subgroups experiencing higher rates of hospitalization. The total fraction of schizophrenia hospital admissions attributable to non-optimal minimum temperature is 3.45 % (CI: -4.91-10.80 %) and high minimum temperature is 0.28 % (CI: -1.18-1.78 %). We found that non-whites and males appear to be at a slightly increased risk than the general population, although there did not appear to be a statistically significant difference. A conservative estimate of healthcare costs annually from non-optimal temperature attributed schizophrenia hospitalization is $1.95 million USD. Therefore, nighttime cooling strategies and efforts could increase the accessibility of shelters to reduce overnight exposure to extreme air temperature.
We examine the impact of temperature on mortality in Mexico using daily data over the period 1998-2017 and find that 3.8 percent of deaths in Mexico are caused by suboptimal temperature (26,000 every year). However, 92 percent of weather-related deaths are induced by cold (<12 degrees C) or mildly cold (12-20 degrees C) days and only 2 percent by outstandingly hot days (>32 degrees C). Furthermore, temperatures are twice as likely to kill people in the bottom half of the income distribution. Finally, we show causal evidence that the Seguro Popular, a universal health care policy, has saved at least 1,600 lives per year from cold weather since 2004.
BACKGROUND: Health disparities exist between urban and rural populations, yet research on rural-urban disparities in temperature-mortality relationships is limited. As inequality in the United States increases, understanding urban-rural and regional differences in the temperature-mortality association is crucial. OBJECTIVE: We examined regional and urban-rural differences of the temperature-mortality association in North Carolina (NC), USA, and investigated potential effect modifiers. METHODS: We applied time-series models allowing nonlinear temperature-mortality associations for 17 years (2000-2016) to generate heat and cold county-specific estimates. We used second-stage analysis to quantify the overall effects. We also explored potential effect modifiers (e.g. social associations, greenness) using stratified analysis. The analysis considered relative effects (comparing risks at 99th to 90th temperature percentiles based on county-specific temperature distributions for heat, and 1st to 10th percentiles for cold) and absolute effects (comparing risks at specific temperatures). RESULTS: We found null effects for heat-related mortality (relative effect: 1.001 (95% CI: 0.995-1.007)). Overall cold-mortality risk for relative effects was 1.019 (1.015-1.023). All three regions had statistically significant cold-related mortality risks for relative and absolute effects (relative effect: 1.019 (1.010-1.027) for Coastal Plains, 1.021 (1.015-1.027) for Piedmont, 1.014 (1.006-1.023) for Mountains). The heat mortality risk was not statistically significant, whereas the cold mortality risk was statistically significant, showing higher cold-mortality risks in urban areas than rural areas (relative effect for heat: 1.006 (0.997-1.016) for urban, 1.002 (0.988-1.017) for rural areas; relative effect for cold: 1.023 (1.017-1.030) for urban, 1.012 (1.001-1.023) for rural areas). Findings are suggestive of higher relative cold risks in counties with the less social association, higher population density, less green-space, higher PM(2.5,) lower education level, higher residential segregation, higher income inequality, and higher income (e.g., Ratio of Relative Risks 1.72 (0.68, 4.35) comparing low to high education). CONCLUSION: Results indicate cold-mortality risks in NC, with potential differences by regional, urban-rural areas, and community characteristics.
BACKGROUND: Accurate and precise estimates of ambient air temperatures that can capture fine-scale within-day variability are necessary for studies of air temperature and health. METHOD: We developed statistical models to predict temperature at each hour in each cell of a 927-m square grid across the Northeast and Mid-Atlantic United States from 2003 to 2019, across ~4000 meteorological stations from the Integrated Mesonet, using inputs such as elevation, an inverse-distance-weighted interpolation of temperature, and satellite-based vegetation and land surface temperature. We used a rigorous spatial cross-validation scheme and spatially weighted the errors to estimate how well model predictions would generalize to new cell-days. We assess the within-county association of temperature and social vulnerability in a heat wave as an example application. RESULTS: We found that a model based on the XGBoost machine-learning algorithm was fast and accurate, obtaining weighted root mean square errors (RMSEs) around 1.6 K, compared to standard deviations around 11.0 K. We found similar accuracy when validating our model on an external dataset from Weather Underground. Assessing predictions from the North American Land Data Assimilation System-2 (NLDAS-2), another hourly model, in the same way, we found it was much less accurate, with RMSEs around 2.5 K. This is likely due to the NLDAS-2 model’s coarser spatial resolution, and the dynamic variability of temperature within its grid cells. Finally, we demonstrated the health relevance of our model by showing that our temperature estimates were associated with social vulnerability across the region during a heat wave, whereas the NLDAS-2 showed a much weaker association. CONCLUSION: Our high spatiotemporal resolution air temperature model provides a strong contribution for future health studies in this region.
BACKGROUND: Older adults are particularly vulnerable to the adverse health effects of extreme temperature-related events. A growing body of literature highlights the importance of the natural environment, including air pollution and sunlight, on cognitive health. However, the relationship between exposure to outdoor temperatures and cognitive functioning, and whether there exists any differences across climate region, remains largely unexplored. We address this gap by examining the temperature-cognition association, and whether there exists any variation across climate regions in a national cohort of aging adults. METHODS: In this cross-sectional study, we obtained data on temperature exposure based on geocoded residential location of participants in the REasons for Geographic And Racial Differences in Stroke (REGARDS) study. For each participant, this information was linked to their cognitive scores from Word List Learning and Recall tests to assess cognitive functioning. We used distributed lag non-linear models (dlnm) to model temperature effects over 2 days. Multivariable linear regression was used to compute temperature-cognitive functioning associations, adjusted for important covariates. Region-specific (“Dry”, “Mediterranean/oceanic”, “Tropical” and “Continental”) associations were examined by including an interaction term between climate region and temperature. RESULTS: Amongst 20,687 individuals (mean age = 67.8; standard deviation = 9.2), exposure to region-specific extreme cold temperatures in the “dry” region (e.g., Arizona) over 2 days was associated with lower cognitive scores (Mean Difference [MD]: -0.76, 95% Confidence Interval [CI]: - 1.45, - 0.07). Associations remained significant for cumulative effects of temperature over 2 days. Extremely cold exposure in the “Mediterranean/oceanic” region (e.g., California) over 2 days was also associated with significantly lower cognitive performance (MD: -0.25, 95% CI: - 0.47, - 0.04). No significant associations were observed for exposure to hot temperatures. Cognitive performance was slightly higher in late summer and fall compared to early summer. CONCLUSION: We noted adverse cognitive associations with cold temperatures in traditionally warmer regions of the country and improved cognition in summer and early fall seasons. While we did not observe very large significant associations, this study deepens understanding of the impact of climate change on the cognitive health of aging adults and can inform clinical care and public health preparedness plans.
BACKGROUND: Extreme heat exposure can lead to premature death. Climate change is expected to increase the frequency, intensity, and duration of extreme heat events, resulting in many additional heat-related deaths globally, as well as changing the nature of extreme cold events. At the same time, vulnerability to extreme heat has decreased over time, probably due to a combination of physiological, behavioural, infrastructural, and technological adaptations. We aimed to account for these changes in vulnerability and avoid overstated projections for temperature-related mortality. We used the historical observed decrease in vulnerability to improve future mortality estimates. METHODS: We used historical mortality and temperature data from 208 US cities to quantify how observed changes in vulnerability from 1973 to 2013 affected projections of temperature-related mortality under various climate scenarios. We used geographically structured meta-regression to characterise the relationship between temperature and mortality for these urban populations over the specified time period. We then used the fitted relationships to project mortality under future climate conditions. FINDINGS: Between Oct 26, 2018, and March 9, 2020, we established that differences in vulnerability to temperature were geographically structured. Vulnerability decreased over time in most areas. US mortalities projected from a 2°C increase in mean temperature decreased by more than 97% when using 2003-13 data compared with 1973-82 data. However, these benefits declined with increasing temperatures, with a 6°C increase showing only an 84% decline in projected mortality based on 2003-13 data. INTERPRETATION: Even after accounting for adaptation, the projected effects of climate change on premature mortality constitute a substantial public health risk. Our work suggests large increases in temperature will require additional mitigation to avoid excess mortality from heat events, even in areas with high air conditioning coverage in place. FUNDING: The US Environmental Protection Agency and Abt Associates.
BACKGROUND: Research on temperature and respiratory hospitalizations is lacking in the southeastern U.S. where cold weather is relatively rare. This retrospective study examined the association between cold waves and pneumonia and influenza (P&I) emergency department (ED) visits and hospitalizations in three metro-Atlanta hospitals. METHODS: We used a case-crossover design, restricting data to the cooler seasons of 2009-2019, to determine whether cold waves influenced ED visits and hospitalizations. This analysis considered effects by race/ethnicity, age, sex, and severity of comorbidities. We used generalized additive models and distributed lag non-linear models to examine these relationships over a 21-day lag period. RESULTS: The odds of a P&I ED visit approximately one week after a cold wave were increased by as much as 11%, and odds of an ED visit resulting in hospitalization increased by 8%. For ED visits on days with minimum temperatures >20 °C, there was an increase of 10-15% in relative risk (RR) for short lags (0-2 days), and a slight decrease in RR (0-5%) one week later. For minimum temperatures <0 °C, RR decreased at short lags (5-10%) before increasing (1-5%) one week later. Hospital admissions exhibited a similar, but muted, pattern. CONCLUSION: Unusually cold weather influenced ED visits and admissions in this population.
Nitrogen dioxide (NO2) is responsible for aggravating respiratory diseases, particularly asthma. The aim of this study is to investigate the association between NO2 exposure and asthma emergency department (ED) visits during the cold season (November-February) in five populated locations (Sacramento, San Francisco, Fresno, Los Angeles, and San Diego) of California from 2005 to 2015 (1320 Days). Conditional logistic regression models were used to obtain the odds ratio (OR) and 95% confidence interval Cl)( associated with a 5 ppb increase in NO2 concentration for the 19,735 ED visits identified. An increase in NO2 exposure increased the odds of having asthma ED visits for the studied population. The potential effect modification by sex (female and male), race (White, Black, Hispanic, and Asian), and age (2-5, 6-18, 19-40, 41-64, and ?65) was explored. A 5 ppb increase in the concentration of NO2 during lag 0-30 was associated with a 56% increase in the odds of having an asthma ED visit (OR 1.560, Cl: 1.428-1.703). Sex was not found lo be a modifier. Asthma ED visits among all the racesiehnicities (except Asians) were associated with NO2 exposure. Whiles had the highest OR 75% (OR 1.750, CI: 1A17-2.160) at lag 0-30 in response to NO2 exposure. The association between NO2 exposure and asthma ED visits was positive among all age groups except fur 19 to 40 years old; the OR was higher among 2 to 18 year old (al lag 0-30: age group 2-5 (OR – 1.699, CI: 1.399-2.062), and age group 6-18 (OR – 1.568, CII.348-1.825)). For stratification by location, San Diego and Fresno were found to have the highest OR, compared lo the other studied locations. (C) 2020 Elsevier B.V. All rights reserved.
Evidence shows that climate change may have adverse effects on human health. The purpose of this study was to investigate the relation between Physiologically Equivalent Temperature (PET) and cardiovascular hospital admissions in Ahvaz. Distributed Lag Non-linear Models (DLNM) combined with quasi-Poisson regression models were used to investigate the effect of PET on hospital admissions. Low PET values (6.4 °C, 9.9 °C and 16.9 °C) in all lags, except lag 0-30, significantly decreased the risk of hospital admissions for total cardiovascular diseases, hypertension, ischemic heart diseases, and cardiovascular admissions in men, women and ≤65 years. But, low PET (6.4 °C) in lags 0 and 0-2 significantly increased the risk of hospital admissions for cerebrovascular diseases; and high PET values increased the risk of ischemic heart diseases and in men. Both cold and hot stress are involved in cardiovascular hospital admissions.
Background: There are few epidemiological studies on the relation between temperature changes and adverse pregnancy outcomes. The purpose of this study was to determine the relation between Physiological Equivalent Temperature (PET) with adverse pregnancy outcomes including stillbirth, low birth weight (LBW), preterm labor (PTL), spontaneous abortion (SA), preeclampsia and hypertension in Ahvaz, Iran. Methods: Distributed Lag Non-linear Models (DLNM) combined with quasi-Poisson regression were used to investigate the effect of PET on adverse pregnancy outcomes. In this study the effect of time trend, air pollutants (NO2, SO2 and PM10), and weekdays were adjusted. Results: High PET (45.4 C°, lag = 0) caused a significant increase in risk of stillbirth. Also, high levels of PET (45.4, 43.6, 42.5 C°, lag = 0–6) and low levels of PET (9.9, 16.9 C°, lags = 0, 0–13, 0–21) significantly increased the risk of LBW. But, low levels of PET (6.4, 9.9, 16.9 C°, lags = 0–6, 0–13) reduced the risk of gestational hypertension. Conclusion: The results of this study showed that hot and cold thermal stress may be associated with increased risk of stillbirth, and LBW in Ahvaz.
BACKGROUND: In recent years, temperature fluctuations and adverse weather events have become major concerns, influencing overall mortality and morbidity. While the association between extreme temperatures and atrial fibrillation (AF) has been supported by research, there is limited evidence on the ability of AF patients to adapt to the changing temperatures. We explored this question among AF patients in Israel featured by extreme temperature conditions. METHODS: We examined the association between exposure to extreme temperatures and hospitalizations related to AF in a nationwide cohort in Israel. A case-crossover design with a distributed nonlinear model (DLNM) was applied to assess possible effects of temperature fluctuations during each season. We considered the 7 days prior to the event as the possible window period. RESULTS: During 2004-2018 we recorded a total of 54,909 hospitalizations for AF. Low temperatures in winter and high in summer adversely affected AF-related hospitalizations. The effect recorded for the first few weeks of each season was of higher magnitude and decreased or faded off completely as the seasons progressed (OR in winter: from 1.14, 95%CI 0.98, 1.32 to 0.90, 95%CI: 0.77, 1.06;OR in summer: from 1.95, 95%CI: 1.51, 2.52 to 1.22, 95%CI: 0.90, 1.65). Patients living in the south region and patients with low socioeconomic status were more susceptible to extreme temperatures. CONCLUSIONS: Although extreme hot and cold temperatures are associated with an increased risk of hospitalization for AF, the patients are likely to adapt to temperature change over the course of the first weeks of the season.
We have analyzed the long-term temperature trends and extreme temperature events in Saudi Arabia between 1979 and 2019. Our study relies on high-resolution, consistent, and complete ERA5 reanalysis data from the European Centre for Medium-Range Weather Forecasts (ECMWF). We evaluated linear trends in several climate descriptors, including temperature, dewpoint temperature, thermal comfort, and extreme event indices. Previous works on this topic used data from weather station observations over limited time intervals and did not include temperature data for recent years. The years 2010-19 have been the warmest decade ever observed by instrumental temperature monitoring and are the eight warmest years on record. Therefore, the earlier results may be incomplete, and their results may no longer be relevant. Our findings indicate that, over the past four decades, Saudi Arabia has warmed up at a rate that is 50% higher than the rest of the landmass in the Northern Hemisphere. Moreover, moisture content of the air has significantly increased in the region. The increases of temperature and humidity have resulted in the soaring of dewpoint temperature and thermal discomfort across the country. These increases are more substantial during summers, which are already very hot relative to winters. Such changes may be dangerous to people over vast areas of the country. If the current trend persists into the future, human survival in the region will be impossible without continuous access to air conditioning.
BACKGROUND: Exposure to heat during pregnancy has been associated with reduced fetal growth. Less is known about associations with cold and the potential for critical time windows of exposure. OBJECTIVES: We aimed to evaluate, in a national retrospective cohort, critical windows of susceptibility during pregnancy to extreme temperatures (low and high) and fetal growth, among 624,940 singleton term births in Israel during the period 2010-2014. METHODS: Temperature exposures were estimated using a spatially refined gridded climate data set with a 1-h and 1-km2 resolution. Percentiles of temperature were categorized by climatic zone for the entire pregnancy and by trimesters and weeks. Generalized additive models with the distributed lag nonlinear model framework were used to estimate unadjusted and adjusted associations between percentiles and categories of temperature and fetal growth markers: term [births after 36 weeks of gestational age (GA)] mean birth weight and term low birth weight (tLBW, term infants with birth weight below 2,500 g). RESULTS: After adjustment, extreme temperatures (percentiles) during the entire pregnancy were associated with a lower mean birth weight { ≤ 10th vs. 41st-50th percentile: – 56 g [95% confidence interval (CI): – 63 g, – 50 g)]; > 90th vs. 41st-50th percentile: – 65 g; 95% CI: – 72 g, – 58 g}. Similar inverse U-shaped patterns were observed for all trimesters, with stronger associations for heat than for cold and for exposures during the third trimester. For heat, results suggest critical windows between 3-9 and 19-34 GA-weeks, with the strongest association estimated at 3 GA-weeks (temperature > 90th vs. 41st-50th percentiles: – 3.8 g; 95% CI: – 7.1 g, – 0.4 g). For cold, there was a consistent trend of null associations early in pregnancy and stronger inverse associations over time, with the strongest association at 36 GA-week ( ≤ 10th vs. 41st-50th percentiles: – 2.9 g; 95% CI: – 6.5 g, 0.7g). For tLBW, U-shape patterns were estimated for the entire pregnancy and third trimester exposures, as well as nonsignificant associations with heat for 29-36 GA-weeks. Generally, the patterns of associations with temperatures during the entire pregnancy were consistent when stratified by urbanicity and geocoding hierarchy, when estimated for daily minimum and maximum temperatures, when exposures were classified based on temperature distributions in 49 natural regions, and when estimated for all live births. DISCUSSION: Findings from our study of term live births in Israel (2010-2014) suggest that exposure to extreme temperatures, especially heat, during specific time windows may result in reduced fetal growth. https://doi.org/10.1289/EHP8117.
Recent work by Kephart et al.(1) updates estimates for mortality burden attributable to non-optimal ambient temperatures in Latin America, which helps to understand the climate-related health risks and burden in less-developed areas. Here, we discuss the main findings and focus on methodology that remains controversial in heat health field.
CONTEXT: Tropical areas and small islands are identified as highly vulnerable to climate change, and already experiencing shifts in their temperature distribution. However, the knowledge on the health impacts of temperatures under tropical marine climate is limited. We explored the influence of temperature on mortality in four French overseas regions located in French Guiana, French West Indies, and in the Indian Ocean, between 2000 and 2015. METHOD: Distributed lag non-linear generalized models linking temperature and mortality were developed in each area, and relative risks were combined through a meta-analysis. Models were used to estimate the fraction of mortality attributable to non-optimal temperatures. The role of humidity was also investigated. RESULTS: An increased risk of mortality was observed when the temperature deviated from median. Results were not modified when introducing humidity. Between 2000 and 2015, 979 deaths [confidence interval (CI) 95% 531:1359] were attributable to temperatures higher than the 90th percentile of the temperature distribution, and 442 [CI 95% 178:667] to temperature lower than the 10th percentile. DISCUSSION: Heat already has a large impact on mortality in the French overseas regions. Results suggest that adaptation to heat is relevant under tropical marine climate.
The gradual increase in temperatures and changes in relative humidity, added to the aging and socioeconomic conditions of the population, may represent problems for public health, given that future projections predict even more noticeable changes in the climate and the age pyramid, which require analyses at an appropriate spatial scale. To our knowledge, an analysis of the synergic effects of several climatic and socioeconomic conditions on hospital admissions and deaths by cardiorespiratory and mental disorders has not yet been performed in Brazil. Statistical analyses were performed using public time series (1996-2015) of daily health and meteorological data from 16 metropolitan regions (in a subtropical climate zone in South America). Health data were stratified into six groups according to gender and age ranges (40-59; 60-79; and ≥80 years old) for each region. For the regression analysis, two distributions (Poisson and binomial negative) were tested with and without zero adjustments for the complete series and percentiles. Finally, the relative risks were calculated, and the effects based on exposure-response curves were evaluated and compared among regions. The negative binomial distribution fit the data best. High temperatures and low relative humidity were the most relevant risk factors for hospitalizations for cardiovascular diseases (lag = 0), while minimum temperatures were important for respiratory diseases (lag = 2 or 3 days). Temperature extremes, both high and low, were the most important risk factors for mental illnesses at lag 0. Groups with people over 60 years old presented higher risks for cardiovascular and respiratory diseases, while this was observed for the adult group (40-59 years old) in relation to mental disorders. In general, no major differences were found in the results between men and women. However, regions with higher urbanization levels presented risks, mainly for respiratory diseases, while the same was observed for cardiovascular diseases for regions with lower levels of urbanization. The Municipal Human Development Index is an important factor for the occurrence of diseases and deaths for all regions, depending on the evaluated group, representing high risks for health outcomes (the value for hospitalization for cardiovascular diseases was 1.6713 for the female adult group in the metropolitan region Palmas, and the value for hospitalization for respiratory diseases was 1.7274 for the female adult group in the metropolitan region Campo Mourão). In general, less developed regions have less access to adequate health care and better living conditions.
BACKGROUND: There is an urgent need for more information about the climate change impact on health in order to strengthen the commitment to tackle climate change. However, few studies have quantified the health impact of climate change in Brazil and in the Latin America region. In this paper, we projected the impacts of temperature on cardiovascular (CVD) mortality according to two climate change scenarios and two regionalized climate model simulations in Brazilian cities. METHODS: We estimated the temperature-CVD mortality relationship in 21 Brazilian cities, using distributed lag non-linear models in a two-stage time-series analysis. We combined the observed exposure-response functions with the daily temperature projected under two representative concentration pathways (RCP), RCP8.5 and RCP4.5, and two regionalized climate model simulations, Eta-HadGEM2-ES and Eta-MIROC5. RESULTS: We observed a trend of reduction in mortality related to low temperatures and a trend of increase in mortality related to high temperatures, according to all the investigated models and scenarios. In most places, the increase in mortality related to high temperatures outweighed the reduction in mortality related to low temperatures, causing a net increase in the excess temperature-related mortality. These trends were steeper according to the higher emission scenario, RCP8.5, and to the Eta-HadGEM2-ES model. According to RCP8.5, our projections suggested that the temperature-related mortality fractions in 2090-99 compared to 2010-2019 would increase by 8.6% and 1.7%, under Eta-HadGEM2-ES and Eta-MIROC5, respectively. According to RCP4.5, these values would be 0.7% and -0.6%. CONCLUSIONS: For the same climate model, we observed a greater increase trend in temperature-CVD mortality according to RCP8.5, highlighting a greater health impact associated with the higher emission scenario. Our results may be useful to support public policies and strategies for mitigation of and adaptation to climate change, particularly in the health sector.
BACKGROUND: Extreme temperatures may lead to adverse pregnancy and birth outcomes, including low birthweight. Studies on the impact of temperature on birthweight have been inconclusive due to methodological challenges related to operationalizing temperature exposure, the definitions of exposure windows, accounting for gestational age, and a limited geographic scope. METHODS: We combined data on individual-level term live births (N≈15 million births) from urban areas in Brazil, Chile, and Mexico from 2010 to 2015 from the SALURBAL study (Urban Health in Latin America) with high-resolution daily air temperature data and computed average ambient temperature for every month of gestation for each newborn. Associations between full-term birthweight and average temperature during gestation were analyzed using multi-level distributed lag non-linear models that adjusted for newborn’s sex, season of conception, and calendar year of child’s birth; controlled for maternal age, education, partnership status, presence of previous births, and climate zone; and included a random term for the sub-city of mother’s residence. FINDINGS: Higher temperatures during the entire gestation are associated with lower birthweight, particularly in Mexico and Brazil. The cumulative effect of temperature on birthweight is mostly driven by exposure to higher temperatures during months 7-9 of gestation. Higher maternal education can attenuate the temperature-birthweight associations. INTERPRETATION: Our work shows that climate-health impacts are likely to be context- and place-specific and warrants research on temperature and birthweight in diverse climates to adequately anticipate global climate change. Given the high societal cost of suboptimal birthweight, public health efforts should be aimed at diminishing the detrimental effect of higher temperatures on birthweight. FUNDING: The Wellcome Trust.
Climate change and urbanization are rapidly increasing human exposure to extreme ambient temperatures, yet few studies have examined temperature and mortality in Latin America. We conducted a nonlinear, distributed-lag, longitudinal analysis of daily ambient temperatures and mortality among 326 Latin American cities between 2002 and 2015. We observed 15,431,532 deaths among ≈2.9 billion person-years of risk. The excess death fraction of total deaths was 0.67% (95% confidence interval (CI) 0.58-0.74%) for heat-related deaths and 5.09% (95% CI 4.64-5.47%) for cold-related deaths. The relative risk of death was 1.057 (95% CI 1.046-1.067%) per 1 °C higher temperature during extreme heat and 1.034 (95% CI 1.028-1.040%) per 1 °C lower temperature during extreme cold. In Latin American cities, a substantial proportion of deaths is attributable to nonoptimal ambient temperatures. Marginal increases in observed hot temperatures are associated with steep increases in mortality risk. These risks were strongest among older adults and for cardiovascular and respiratory deaths.
BACKGROUND: In Latin America, where climate change and rapid urbanization converge, non-optimal ambient temperatures contribute to excess mortality. However, little is known about area-level characteristics that confer vulnerability to temperature-related mortality. OBJECTIVES: Explore city-level socioeconomic and demographic characteristics associated with temperature-related mortality in Latin American cities. METHODS: The dependent variables quantify city-specific associations between temperature and mortality: heat- and cold-related excess death fractions (EDF, or percentages of total deaths attributed to cold/hot temperatures), and the relative mortality risk (RR) associated with 1 °C difference in temperature in 325 cities during 2002-2015. Random effects meta-regressions were used to investigate whether EDFs and RRs associated with heat and cold varied by city-level characteristics, including population size, population density, built-up area, age-standardized mortality rate, poverty, living conditions, educational attainment, income inequality, and residential segregation by education level. RESULTS: We find limited effect modification of cold-related mortality by city-level demographic and socioeconomic characteristics and several unexpected associations for heat-related mortality. For example, cities in the highest compared to the lowest tertile of income inequality have all-age cold-related excess mortality that is, on average, 3.45 percentage points higher (95% CI: 0.33, 6.56). Higher poverty and higher segregation were also associated with higher cold EDF among those 65 and older. Large, densely populated cities, and cities with high levels of poverty and income inequality experience smaller heat EDFs compared to smaller and less densely populated cities, and cities with little poverty and income inequality. DISCUSSION: Evidence of effect modification of cold-related mortality in Latin American cities was limited, and unexpected patterns of modification of heat-related mortality were observed. Socioeconomic deprivation may impact cold-related mortality, particularly among the elderly. The findings of higher levels of poverty and income inequality associated with lower heat-related mortality deserve further investigation given the increasing importance of urban adaptation to climate change.
This research concerns the identification of a pattern between the occurrence of extreme weather conditions, such as cold waves and heat waves, and hospitalization for cardiovascular diseases (CVDs), in the University Hospital of Santa Maria (HUSM) in southern Brazil between 2012 and 2017. The research employed the field experiment method to measure the biometeorological parameters associated with hospital admissions in different seasons, such as during extreme weather conditions such as a cold wave (CW) or a heat wave (HW), using five thermal comfort indices: physiologically equivalent temperature (PET), new standard effective temperature (SET), predicted mean vote (PMV), effective temperatures (ET), and effective temperature with wind (ETW). The hospitalizations were recorded as 0.775 and 0.726 admissions per day for the winter and entire study periods, respectively. The records for extreme events showed higher admission rates than those on average days. The results also suggest that emergency hospitalizations for heart diseases during extreme weather events occurred predominantly on days with thermal discomfort. Furthermore, there was a particularly high risk of hospitalization for up to seven days after the end of the CW. Further analyses showed that cardiovascular hospitalizations were higher in winter than in summer, suggesting that CWs are more life threatening in wintertime.
A thermal comfort index for the Northeast of Brazil was analyzed for two scenarios of climatic changes, A1B and A2, for 2021-2080, and compared with the reference period 1961-1990. A technique of regionalization was applied to rainfall, maximum and minimum temperature data from meteorological stations, obtained by statistical downscaling of projections from four global climate models. The results pointed to a significant reduction of rainfall and an increase of temperature for three different climatically homogeneous subregions. Regarding the thermal comfort index, the results point to an increase in days with heat discomfort between 2021 and 2080. In the northern portion, the higher percentage of days with heat discomfort will be significant since the first half of the period under appreciation, i.e., from 2021 to 2050. Conversely, in the eastern of northeastern Brazil, the increase of days with heat discomfort should happen in the period from 2051 to 2080, whereas the central-western part of the region, which, in the reference period, had recorded less than 1% of days with heat discomfort, might see an elevation of that percentage to 7% between 2021 and 2050, potentially reaching 48% of its days made uncomfortable by heat between 2051 and 2080.
This work is taken up to evaluate the relationship between the thermal comfort of spectators and athletes and the prevailing meteorological conditions during Rio 2016 Olympic Games. Empirical and physiological thermal comfort indices are calculated from data collected from an automatic weather station installed near the Olympic Stadium and interviews with the spectators. The study period was marked by a gradual rise in air temperature and by the occurrence of two significant weather events associated with wind gusts, which caused disturbances in some areas of the competitions. ET and NET were below the air temperature, indicating that both humidity and wind contributed to the reduction of the human-biometeorological indices. Majority of the interviewed persons reported comfortable sensation and weather conditions. These perceptions corroborate results of the thermal comfort indices calculated for these resting spectators. The comfort indices calculated for the athletes with high level of physical activity showed that PET estimated hotter thermal sensation those for the individuals at rest, indicating that the physical type of a person may strongly influence the thermal sensation and comfort during intense physical activity. Increasing trend observed in all the indices of human thermal comfort during the period of study shows consistency among them.
The expansion of the invasive mosquito Aedes aegypti L. (Diptera: Culicidae) towards temperate regions in the Americas is causing concern because of its public health implications. As for other insects, the distribution limits of Ae. aegypti have been suggested to be related to minimum temperatures and to be controlled mainly by cold tolerance. The aim of this study was to assess the daily mortality of immature stages of Ae. aegypti under natural winter conditions in Buenos Aires, Argentina, in relation to preceding thermal conditions. The experiment was performed outdoors, and one cohort of larvae was started each week for 16 weeks, and reared up to the emergence of the adults. Three times a week, larvae, pupae and emerged adults were counted, and these data were used to calculate the daily mortality of larvae, pupae and adults and to analyze their relationship with thermal conditions. The results showed that mortality was generally low, with a few peaks of high mortality after cold front events. The mortality of pupae and larvae showed a higher correlation with the cooling degree hours of previous days than with the minimum, maximum or mean temperatures. Pupae and adults showed to be more vulnerable to low temperatures than larvae. A delay in mortality was observed in relation to the low temperature events, with a proportion of individuals dying in a later stage after the end of the cold front. These results suggest that thermal conditions during cold fronts in Buenos Aires are close to the tolerance limit of the local Ae. aegypti population. The wide range of responses of different individuals suggests that low winter temperatures may constitute a selective force, leading the population to a higher tolerance to low temperatures, which might favor the further expansion of this species towards colder regions.
Outdoor thermal comfort is significantly affected by climate, including macroclimate, local climate, and microclimate. However, the combined impacts of macroclimate and microclimate factors are less understood in previous thermal comfort studies. This paper employed 43 previ-ously published studies to comprehensively explore the impacts of macro-and micro-climatic factors on the outdoor thermal comfort. The relative importance of these influencing factors was assessed via five verified artificial neural network (ANN) models. For studies employing subjec-tive thermal indices which collected participants’ thermal perceptions, the neutral temperature expressed by physiologically equivalent temperature (PET) was found to be significantly corre-lated with macroclimate factors, especially the latitude and season. In studies employing only objective thermal indices, it was found that macroclimate factors, such as the latitude, distance from the sea, and altitude, have similar contribution to the outdoor thermal comfort as micro-climate factors, such as height to width ratio (H/W) and sky view factor. Results resonated with previous findings that outdoor comfort can be improved by changing urban geometry, vegetation, surfaces, and waterbodies. Future design and planning works should consider both macroclimate and microclimate factors and carefully design urban geometry and morphology to improve out-door thermal comfort for regions with disadvantageous macroclimates.
Exposure to extreme environmental heat or cold during military activities can impose severe thermal strain, leading to impairments in task performance and increasing the risk of exertional heat (including heat stroke) and cold injuries that can be life-threatening. Substantial individual variability in physiological tolerance to thermal stress necessitates an individualized approach to mitigate the deleterious effects of thermal stress, such as physiological monitoring of individual thermal strain. During heat exposure, measurements of deep-body (T(c)) and skin temperatures and heart rate can provide some indication of thermal strain. Combining these physiological variables with biomechanical markers of gait (in)stability may provide further insight on central nervous system dysfunction – the key criterion of exertional heat stroke (EHS). Thermal strain in cold environments can be monitored with skin temperature (peripheral and proximal), shivering thermogenesis and T(c). Non-invasive methods for real-time estimation of T(c) have been developed and some appear to be promising but require further validation. Decision-support tools provide useful information for planning activities and biomarkers can be used to improve their predictions, thus maximizing safety and performance during hot- and cold-weather operations. With better understanding on the etiology and pathophysiology of EHS, the microbiome and markers of the inflammatory responses have been identified as novel biomarkers of heat intolerance. This review aims to (i) discuss selected physiological and biomechanical markers of heat or cold strain, (ii) how biomarkers may be used to ensure operational readiness in hot and cold environments, and (iii) present novel molecular biomarkers (e.g., microbiome, inflammatory cytokines) for preventing EHS.
BACKGROUND: Exposure to cold or hot temperatures is associated with premature deaths. We aimed to evaluate the global, regional, and national mortality burden associated with non-optimal ambient temperatures. METHODS: In this modelling study, we collected time-series data on mortality and ambient temperatures from 750 locations in 43 countries and five meta-predictors at a grid size of 0·5° × 0·5° across the globe. A three-stage analysis strategy was used. First, the temperature-mortality association was fitted for each location by use of a time-series regression. Second, a multivariate meta-regression model was built between location-specific estimates and meta-predictors. Finally, the grid-specific temperature-mortality association between 2000 and 2019 was predicted by use of the fitted meta-regression and the grid-specific meta-predictors. Excess deaths due to non-optimal temperatures, the ratio between annual excess deaths and all deaths of a year (the excess death ratio), and the death rate per 100 000 residents were then calculated for each grid across the world. Grids were divided according to regional groupings of the UN Statistics Division. FINDINGS: Globally, 5 083 173 deaths (95% empirical CI [eCI] 4 087 967-5 965 520) were associated with non-optimal temperatures per year, accounting for 9·43% (95% eCI 7·58-11·07) of all deaths (8·52% [6·19-10·47] were cold-related and 0·91% [0·56-1·36] were heat-related). There were 74 temperature-related excess deaths per 100 000 residents (95% eCI 60-87). The mortality burden varied geographically. Of all excess deaths, 2 617 322 (51·49%) occurred in Asia. Eastern Europe had the highest heat-related excess death rate and Sub-Saharan Africa had the highest cold-related excess death rate. From 2000-03 to 2016-19, the global cold-related excess death ratio changed by -0·51 percentage points (95% eCI -0·61 to -0·42) and the global heat-related excess death ratio increased by 0·21 percentage points (0·13-0·31), leading to a net reduction in the overall ratio. The largest decline in overall excess death ratio occurred in South-eastern Asia, whereas excess death ratio fluctuated in Southern Asia and Europe. INTERPRETATION: Non-optimal temperatures are associated with a substantial mortality burden, which varies spatiotemporally. Our findings will benefit international, national, and local communities in developing preparedness and prevention strategies to reduce weather-related impacts immediately and under climate change scenarios. FUNDING: Australian Research Council and the Australian National Health and Medical Research Council.
Construction sites continue to operate despite inclement weather, exposing workers to unpleasant working circumstances that can lead to various physical and mental health challenges. A thorough literature review yielded 21 challenges for hot weather conditions such as heat stroke, kidney disease, heat cramps, anxiety and depression, and 20 challenges for cold weather conditions like asthma, frostbite, musculoskeletal disorders and hallucination. Workers vulnerable to hot and cold weather based on demographic characteristics were identified. The study also provides 27 strategies to address the challenges experienced in hot and cold weather conditions. Some of these include ensuring that workers stay hydrated, scheduling sufficient rest periods and allowing workers to self-pace. The results of this study will help construction decision-makers and project managers understand the difficulties faced by a field workforce who labors in extreme working conditions on construction sites and will facilitate adoption of strategies that can prevent weather-related physical and mental health problems.
BACKGROUND: Mortality due to enteric infections is projected to increase because of global warming; however, the different temperature sensitivities of major enteric pathogens have not yet been considered in projections on a global scale. We aimed to project global temperature-attributable enteric infection mortality under various future scenarios of sociodemographic development and climate change. METHODS: In this modelling study, we generated global projections in two stages. First, we forecasted baseline mortality from ten enteropathogens (non-typhoidal salmonella, Shigella, Campylobacter, cholera, enteropathogenic Escherichia coli, enterotoxigenic E coli, typhoid, rotavirus, norovirus, and Cryptosporidium) under several future sociodemographic development and health investment scenarios (ie, pessimistic, intermediate, and optimistic). We then estimated the mortality change from baseline attributable to global warming using the product of projected annual temperature anomalies and pathogen-specific temperature sensitivities. FINDINGS: We estimated that in the period 2080-95, the global mean number of temperature-attributable deaths due to enteric infections could be as low as 6599 (95% empirical CI 5441-7757) under the optimistic sociodemographic development and climate change scenario, or as high as 83 888 (67 760-100 015) under the pessimistic scenario. Most of the projected temperature-attributable deaths were from shigellosis, cryptosporidiosis, and typhoid fever in sub-Saharan Africa and South Asia. Considerable reductions in the number of attributable deaths were from viral infections, such as rotaviral and noroviral enteritis, which resulted in net reductions in attributable enteric infection mortality under optimistic scenarios for Latin America and the Caribbean and East Asia and the Pacific. INTERPRETATION: Temperature-attributable mortality could increase under warmer climate and unfavourable sociodemographic conditions. Mitigation policies for limiting global warming and sociodemographic development policies for low-income and middle-income countries might help reduce mortality from enteric infections in the future. FUNDING: Japan Society for the Promotion of Science, Japan Science and Technology Agency, and Spanish Ministry of Economy, Industry, and Competitiveness.
INTRODUCTION: This study quantitatively described the disease burden of diabetes and kidney disease attributable to non-optimal temperatures and explored the influencing factors. METHODS: We quantitatively described the mortality burden of diabetes and kidney disease attributable to non-optimal temperatures in six countries (China, USA, South Africa, Australia, Iraq, Portugal), and compare trends in mortality in six countries from 1990 to 2019. We used the APC model to analyse age, period, and cohort effects on mortality in six countries. We used restricted cubic splines and quantile regression to analyse the association of SDI with mortality and YLL using data from 21 regions in the world. RESULTS: The mortality rates of diabetes and kidney disease in the six countries in 2019 were 1.72% (Australia), 1.83% (China), 2.99% (USA), 3% (Portugal), 7.45% (South Africa) and 8.71% (Iraq) attributable to non-optimal temperatures. Cold was more harmful than heat. The mortality, YLLs of diabetes and kidney disease of male were higher than females. The mortality rate showed an upwards trend with age. The period effect had little changes or showed a slight upwards trend. The cohort effect showed a downwards trend. The regions with higher mortality or YLLs rates were mainly had SDI values of 0.45-0.80. CONCLUSIONS: Among the death burdens of diabetes and kidney disease attributed to non-optimal temperatures, cold had a greater burden than heat. The burden of death was affected by sex, age, period, cohort, and SDI.
Many studies project that climate change is expected to cause a significant number of excess deaths. Yet, in integrated assessment models that determine the social cost of carbon (SCC), human mortality impacts do not reflect the latest scientific understanding. We address this issue by estimating country-level mortality damage functions for temperature-related mortality with global spatial coverage. We rely on projections from the most comprehensive published study in the epidemiology literature of future temperature impacts on mortality (Gasparrini et al. in Lancet Planet Health 1:e360-e367, 2017), which estimated changes in heat- and cold-related mortality for 23 countries over the twenty-first century. We model variation in these mortality projections as a function of baseline climate, future temperature change, and income variables and then project future changes in mortality for every country. We find significant spatial heterogeneity in projected mortality impacts, with hotter and poorer places more adversely affected than colder and richer places. In the absence of income-based adaptation, the global mortality rate in 2080-2099 is expected to increase by 1.8% [95% CI 0.8-2.8%] under a lower-emissions RCP 4.5 scenario and by 6.2% [95% CI 2.5-10.0%] in the very high-emissions RCP 8.5 scenario relative to 2001-2020. When the reduced sensitivity to heat associated with rising incomes, such as greater ability to invest in air conditioning, is accounted for, the expected end-of-century increase in the global mortality rate is 1.1% [95% CI 0.4-1.9%] in RCP 4.5 and 4.2% [95% CI 1.8-6.7%] in RCP 8.5. In addition, we compare recent estimates of climate-change induced excess mortality from diarrheal disease, malaria and dengue fever in 2030 and 2050 with current estimates used in SCC calculations and show these are likely underestimated in current SCC estimates, but are also small compared to more direct temperature effects.
INTRODUCTION: Hot and cold weather events are increasingly becoming a global burden resulting in premature and preventable morbidity and mortality, particularly in vulnerable groups such as older people and people with chronic health conditions. However, risk perception regarding weather is generally poor among vulnerable groups which often acts as a barrier to the uptake of critical health-protective behaviours. A more cohesive understanding of determinants of risk perception is needed to inform public health risk communication and behaviour change interventions that promote protective health behaviours. This scoping literature review aimed to understand factors influencing perception of personal health risks in vulnerable groups as a result of exposure to hot and cold weather events. METHODS: A five-stage scoping review framework was followed. Searches were run across Medline, PsychInfo, Web of Science and EMBASE. Papers were included if they provided rationale for risk perceptions in vulnerable groups in indoor/domestic environments and focussed on samples from OECD countries. RESULTS: In total, 13 out of 15,554 papers met the full inclusion criteria. The majority of papers focused on hot weather events: one study exclusively examined cold weather events and one study addressed both cold and hot weather events. Included papers focused on older adults aged 65+ years. The papers identified eight factors that were associated with older adults’ personal health risk perception of hot and cold weather events: (1) Knowledge of the relationship between hot/cold weather and health risks, (2) presence of comorbidities, (3) age and self-identity, (4) perceived weather severity, (5) Beliefs associated with regional climate, (6) past experience with weather, (7) misconceptions of effectiveness of protective behaviours, and (8) external locus of control. CONCLUSIONS: Future research should explore risk communication methods by implementing the identified risk perception determinants from this review into health protection interventions targeting older adults. Further understanding is needed regarding risk perceptions in non-elderly vulnerable groups, for examples individuals with chronic diseases or disabilities.
BACKGROUND: Associations between ambient temperature exposure during pregnancy and stillbirth have been reviewed and described in the literature. However, there is no existing review of environmental and epidemiologic methods applied to measure stillbirths resulting from exposure to ambient temperatures during pregnancy. The objective of this study is to systematically review published methods, data sources, and data linkage practices to characterize associations between ambient temperature and stillbirth to inform stillbirth prevention and risk management strategies. METHODS: A systematic review of published studies that assess the association between ambient temperature exposure during pregnancy using any measures or approach and stillbirth was undertaken in Cochrane Library, PubMed, Medline, Scopus, Embase, and Web of Science of studies (2000-2020, inclusive). Selection of studies were assessed by pre-specified eligibility criteria and documented using PRISMA. Citations were managed using EndNote X8 whilst selection, reviewing, and data extraction were performed using Covidence. The screening, selection, and data extraction process consisted of two blind, independent reviews followed by a tertiary independent review. An adapted Critical Appraisal Skills Program (CASP) checklist was used to assess quality and bias. The main findings and characteristics of all studies was extracted and summarized. Where appropriate, a meta-analysis will be performed for measures of association. RESULTS: Among 538 original records, 12 eligible articles were identified that analysed associations between ambient temperature exposure and stillbirth for 42,848 stillbirths among 3.4 million births across seven countries. Varied definitions of stillbirth were reported based on gestational age, birthweight, both, or neither. The overall rate of stillbirth ranged from 1.9 to 38.4 per 1000 among six high-income countries and one low-middle-income country. All study designs were retrospective and included ten cohort studies, three case-crossover studies, and two additional case-control subgroup analysis. Exposure data for ambient temperature was mostly derived from standard municipal or country-level monitors based on weather stations (66.6%) or a forecasting model (16.7%); otherwise, not reported (16.7%). Results were not statistically pooled for a meta-analysis due to heterogeneity of methods and models among included studies. All studies reported associations of increased risk of stillbirth with ambient temperature exposures throughout pregnancy, particularly in late pregnancy. One study estimates 17-19% (PAR) of stillbirths are potentially attributable to chronic exposure to hot and cold ambient temperatures during pregnancy. Overall, risk of stillbirth was observed to increase below 15 °C and above 23.4 °C, where highest risk is above 29.4 °C. CONCLUSION: Exposure to hot and cold temperatures during pregnancy may increase the risk of stillbirth, although a clear causative mechanism remains unknown. Despite lack of causal evidence, existing evidence across diverse settings observed similar effects of increased risk of stillbirth using a variety of statistical and methodological approaches for exposure assessments, exposure windows, and data linkage. Managing exposure to ambient temperatures during pregnancy could potentially decrease risk of stillbirth, particularly among women in low-resource settings where access to safe antenatal and obstetric care is challenging. To fully understand the effects or dose-response relationship of maternal exposure to ambient temperatures and stillbirth, future studies should focus on biological mechanisms and contributing factors in addition to improving measurement of ambient temperature exposure.
To date, no review has focused specifically on the potential modulating role of environmental temperature on the effects of exercise on cognitive function. Despite this, a range of occupations and performance contexts exist (e.g., military personnel, emergency services, sport) where the maintenance of cognitive function in environmentally challenging environments is crucial. Therefore, this systematic review aimed to evaluate the experimental research investigating how manipulating environmental temperature influenced the effects of acute bouts exercise on cognitive functioning from pre-to-post exercise, or during exercise. Studies to be included were assessed by two authors reviewing title, abstract, and then full-text. From the searches conducted, twenty articles were identified which met the inclusion criteria. For the purpose of this review, exercise involved in each study was categorised into low, moderate, and vigorous dosages (dependent on intensity and duration). The results indicate that moderate dosages of exercise help stimulate improved cognitive performance from pre-to-post exercise in temperate conditions, where cold exposure appears to blunt these effects. In addition, hot environments led to cognitive decrements during and post exercise which were often identified in studies that implemented prolonged moderate or vigorous exercise protocols. Therefore, suggesting a combination of heightened physiological strain from increased dose of exercise, alongside heat exposure, can be detrimental to optimal cognitive functioning, whereby executive functioning tasks appeared to be most affected. The findings from this systematic review highlight the potential modulating role of environmental temperature on the effects of exercise on cognitive function. Thus, highlighting the importance of considering the role of environmental temperature for individuals either exercising to elicit desired cognitive benefits or for those involved in physically demanding occupations or performance domains.
BACKGROUND: We investigated adolescents’ feelings of thermal comfort during the educational process in various geographical locations far apart and present recommendations for the adjustment of the thermal environment in schools. METHODS: The prospective international multicenter study took place in 8 locations on different continents. The survey in the form of a questionnaire was carried out among 2800 healthy high school students. The study was divided into “cold season survey,” “warm-season survey,” and heat wave survey. RESULTS: The statistically significant difference between the “cold season survey” score of 4.04 (discomfort) and “warm-season survey” score of 3.47 (slight discomfort) (p = .04) indicates that students feel more thermal discomfort during winter months in all 8 locations. The heat wave survey score was 4.53 (discomfort). During the cold season, 29.24% of high school students felt themselves in full thermal comfort and 76.48% of the students felt themselves relatively comfortable (slightly cool-comfortable-slightly warm). CONCLUSIONS: Even during the ongoing process of climate change, the cold season discomfort remains the main problem for students in classes. This tendency is present in different continents as a universal problem. We recommend keeping an entrance hall and classroom temperatures at different levels and to advise students about proper clothing.
BACKGROUND: There is growing evidence in support of a short-term association between ambient temperature and cardiac arrest attacks that is a serious manifestation of cardiovascular disease and has a high incidence and low survival rate. However, it remains unrecognized about the hazardous temperature exposure types, exposure risk magnitude, and vulnerable populations. OBJECTIVES: We comprehensively summarize prior epidemiological studies looking at the short-term associations of out-of-hospital cardiac arrest (OHCA) with various temperature exposures among different populations. METHODS: We searched PubMed and Web of Science databases from inception to October 2021 for eligible English language. Temperature exposure was categorized into three types: heat (included high temperature, extreme heat, and heatwave), cold (included low temperature and extreme cold), and temperature variation (included diurnal temperature range and temperature change between two adjacent days). Meta-analysis weighted by inverse variance was used to pool effect estimates. RESULTS: This study included 15 studies from 8 countries, totaling around 1 million OHCA events. Extreme heat and extreme cold were significantly associated with an increased risk of OHCA, and the pooled relative risks (RRs) were 1.071 [95 % confidence interval (CI): 1.019-1.126] and 1.662 (95%CI: 1.138-2.427), respectively. The risk of OHCA was also elevated by heatwaves (RR = 1.248, 95%CI: 1.091-1.427) and more intensive heatwaves had a greater effect. Notably, the elderly and males seemed to be more vulnerable to the effects of heat and cold. However, we did not observe a significant association between temperature variation and the risk of OHCA (1.005, 95%CI: 0.999-1.012). CONCLUSION: Short-term exposure to heat and cold may be novel risk factors for OHCA. Considering available studies in limited regions, the temperature effect on OHCA should be urgently confirmed in different regions.
OBJECTIVES: Incidence and prognosis of ST-segment elevation myocardial infarction (STEMI) vary according to ambient temperature and season. We sought to assess whether season and temperature on the day of STEMI are associated with infarct size, microvascular obstruction (MVO), left ventricular ejection fraction (LVEF) and clinical outcomes after primary percutaneous coronary intervention (PCI). METHODS: Individual patient data from 1598 patients undergoing primary PCI in six randomized clinical trials were pooled. Infarct size was evaluated by cardiac magnetic resonance within 30 days in all trials. Patients were categorized either by whether they presented on a day of temperature extremes (minimum temperature <0 °C or maximum temperature >25 °C) or according to season. RESULTS: A total of 558/1598 (34.9%) patients presented with STEMI on a day of temperature extremes, and 395 (24.7%), 374 (23.4%), 481 (30.1%) and 348 (21.8%) presented in the spring, summer, fall and winter. After multivariable adjustment, temperature extremes were independently associated with larger infarct size (adjusted difference 2.8%; 95% CI, 1.3-4.3; P < 0.001) and smaller LVEF (adjusted difference -2.3%; 95% CI, -3.5 to -1.1; P = 0.0002) but not with MVO (adjusted P = 0.12). In contrast, infarct size, MVO and LVEF were unrelated to season (adjusted P = 0.67; P = 0.36 and P = 0.95, respectively). Neither temperature extremes nor season were independently associated with 1-year risk of death or heart failure hospitalization (adjusted P = 0.79 and P = 0.90, respectively). CONCLUSION: STEMI presentation during temperature extremes was independently associated with larger infarct size and lower LVEF but not with MVO after primary PCI, whereas season was unrelated to infarct severity.
BACKGROUND: Cardiovascular disease is the leading cause of death worldwide. Existing studies on the association between temperatures and cardiovascular deaths have been limited in geographic zones and have generally considered associations with total cardiovascular deaths rather than cause-specific cardiovascular deaths. METHODS: We used unified data collection protocols within the Multi-Country Multi-City Collaborative Network to assemble a database of daily counts of specific cardiovascular causes of death from 567 cities in 27 countries across 5 continents in overlapping periods ranging from 1979 to 2019. City-specific daily ambient temperatures were obtained from weather stations and climate reanalysis models. To investigate cardiovascular mortality associations with extreme hot and cold temperatures, we fit case-crossover models in each city and then used a mixed-effects meta-analytic framework to pool individual city estimates. Extreme temperature percentiles were compared with the minimum mortality temperature in each location. Excess deaths were calculated for a range of extreme temperature days. RESULTS: The analyses included deaths from any cardiovascular cause (32 154 935), ischemic heart disease (11 745 880), stroke (9 351 312), heart failure (3 673 723), and arrhythmia (670 859). At extreme temperature percentiles, heat (99th percentile) and cold (1st percentile) were associated with higher risk of dying from any cardiovascular cause, ischemic heart disease, stroke, and heart failure as compared to the minimum mortality temperature, which is the temperature associated with least mortality. Across a range of extreme temperatures, hot days (above 97.5th percentile) and cold days (below 2.5th percentile) accounted for 2.2 (95% empirical CI [eCI], 2.1-2.3) and 9.1 (95% eCI, 8.9-9.2) excess deaths for every 1000 cardiovascular deaths, respectively. Heart failure was associated with the highest excess deaths proportion from extreme hot and cold days with 2.6 (95% eCI, 2.4-2.8) and 12.8 (95% eCI, 12.2-13.1) for every 1000 heart failure deaths, respectively. CONCLUSIONS: Across a large, multinational sample, exposure to extreme hot and cold temperatures was associated with a greater risk of mortality from multiple common cardiovascular conditions. The intersections between extreme temperatures and cardiovascular health need to be thoroughly characterized in the present day-and especially under a changing climate.
BACKGROUND: There is rapidly growing evidence indicating that extreme temperature is a crucial trigger and potential activator of asthma; however, the effects of extreme temperature on asthma are inconsistently reported and the its potential mechanisms remain undefined. OBJECTIVES: This review aims to estimate the impacts of extreme heat, extreme cold, and temperature variations on asthma by systematically summarizing the existing studies from epidemiological evidence to biological plausibility. METHODS: We conducted a systematic search in PubMed, Embase, and Web of Science from inception to June 30, 2022, and we retrieved articles of epidemiology and biological studies which assessed associations between extreme temperatures and asthma. This protocol was registered with PROSPERO (CRD42021273613). RESULTS: From 12,435 identified records, 111 eligible studies were included in the qualitative synthesis, and 37 articles were included in the meta-analysis (20 for extreme heat, 16 for extreme cold, and 15 for temperature variations). For epidemiological evidence, we found that the synergistic effects of extreme temperatures, indoor/outdoor environments, and individual vulnerabilities are important triggers for asthma attacks, especially when there is extreme heat or cold. Meta-analysis further confirmed the associations, and the pooled relative risks for asthma attacks in extreme heat and extreme cold were 1.07 (95%CI: 1.03-1.12) and 1.20 (95%CI: 1.12-1.29), respectively. Additionally, this review discussed the potential inflammatory mechanisms behind the associations between extreme temperatures and asthma exacerbation, and highlighted the regulatory role of immunological pathways and transient receptor potential ion channels in asthma triggered by extreme temperatures. CONCLUSIONS: We concluded that both extreme heat and cold could significantly increase the risk of asthma. Additionally, we proposed a potential mechanistic framework, which is important for understanding the disease pathogenesis that uncovers the complex mechanisms of asthma triggered by extreme temperatures and protects the sensitive individuals from impacts of extreme weather events and climate change.
INTRODUCTION: Defining extreme temperatures as the cause of death remains challenging. It is mostly based on circumstantial, macroscopic and microscopic features. METHODS: We retrospectively compared groups of cases of fatal hypothermia, fatal hyperthermia and non-extreme temperature-related deaths. We analysed specific histological findings, focusing on samples from the liver, pancreas and kidney. RESULTS: Between 1 January 2013 and 31 December 2016, 15 autopsies were performed for deaths related to extreme temperatures. They included 11 cases of fatal hypothermia (group A), four cases of fatal hyperthermia (group B) and eight controls (group C). Perinuclear hepatocyte vacuolisation was observed in seven cases of hypothermia, one case of hyperthermia and four controls. Pancreatic cytoarchitecture was well preserved in two cases of hypothermia, one case of hyperthermia and two controls. No particular microscopic feature was found in pancreatic samples. Renal epithelial tubular cell vacuolisation was observed in seven cases of hypothermia and one case of hyperthermia, while it was absent in all controls. Chromogranin A (CgA) was markedly positive in the pancreatic tissue of five cases of fatal hypothermia and one control, and mildly positive in one case of fatal hyperthermia. No significant p-values were observed for any comparisons (p > 0.05), except when hypothermia cases group were compared to the control group for the Armanni-Ebstein phenomenon test (p = 0.0078). CONCLUSIONS: Although our study did not find a specific microscopic marker, hepatocyte vacuolisation, the Armanni-Ebstein phenomenon and pancreatic CgA positivity, taken together, may be useful tools to confirm hypo- and hyperthermia-related deaths, in addition to circumstantial and macroscopic findings.
BACKGROUND: Associations between high and low temperatures and increases in mortality and morbidity have been previously reported, yet no comprehensive assessment of disease burden has been done. Therefore, we aimed to estimate the global and regional burden due to non-optimal temperature exposure. METHODS: In part 1 of this study, we linked deaths to daily temperature estimates from the ERA5 reanalysis dataset. We modelled the cause-specific relative risks for 176 individual causes of death along daily temperature and 23 mean temperature zones using a two-dimensional spline within a Bayesian meta-regression framework. We then calculated the cause-specific and total temperature-attributable burden for the countries for which daily mortality data were available. In part 2, we applied cause-specific relative risks from part 1 to all locations globally. We combined exposure-response curves with daily gridded temperature and calculated the cause-specific burden based on the underlying burden of disease from the Global Burden of Diseases, Injuries, and Risk Factors Study, for the years 1990-2019. Uncertainty from all components of the modelling chain, including risks, temperature exposure, and theoretical minimum risk exposure levels, defined as the temperature of minimum mortality across all included causes, was propagated using posterior simulation of 1000 draws. FINDINGS: We included 64·9 million individual International Classification of Diseases-coded deaths from nine different countries, occurring between Jan 1, 1980, and Dec 31, 2016. 17 causes of death met the inclusion criteria. Ischaemic heart disease, stroke, cardiomyopathy and myocarditis, hypertensive heart disease, diabetes, chronic kidney disease, lower respiratory infection, and chronic obstructive pulmonary disease showed J-shaped relationships with daily temperature, whereas the risk of external causes (eg, homicide, suicide, drowning, and related to disasters, mechanical, transport, and other unintentional injuries) increased monotonically with temperature. The theoretical minimum risk exposure levels varied by location and year as a function of the underlying cause of death composition. Estimates for non-optimal temperature ranged from 7·98 deaths (95% uncertainty interval 7·10-8·85) per 100 000 and a population attributable fraction (PAF) of 1·2% (1·1-1·4) in Brazil to 35·1 deaths (29·9-40·3) per 100 000 and a PAF of 4·7% (4·3-5·1) in China. In 2019, the average cold-attributable mortality exceeded heat-attributable mortality in all countries for which data were available. Cold effects were most pronounced in China with PAFs of 4·3% (3·9-4·7) and attributable rates of 32·0 deaths (27·2-36·8) per 100 000 and in New Zealand with 3·4% (2·9-3·9) and 26·4 deaths (22·1-30·2). Heat effects were most pronounced in China with PAFs of 0·4% (0·3-0·6) and attributable rates of 3·25 deaths (2·39-4·24) per 100 000 and in Brazil with 0·4% (0·3-0·5) and 2·71 deaths (2·15-3·37). When applying our framework to all countries globally, we estimated that 1·69 million (1·52-1·83) deaths were attributable to non-optimal temperature globally in 2019. The highest heat-attributable burdens were observed in south and southeast Asia, sub-Saharan Africa, and North Africa and the Middle East, and the highest cold-attributable burdens in eastern and central Europe, and central Asia. INTERPRETATION: Acute heat and cold exposure can increase or decrease the risk of mortality for a diverse set of causes of death. Although in most regions cold effects dominate, locations with high prevailing temperatures can exhibit substantial heat effects far exceeding cold-attributable burden. Particularly, a high burden of external causes of death contributed to strong heat impacts, but cardiorespiratory diseases and metabolic diseases could also be substantial contributors. Changes in both exposures and the composition of causes of death drove changes in risk over time. Steady increases in exposure to the r
Due to rising temperatures and CO(2) emissions, climate change has become one of the most important global issues. We described the relationship between extreme weather-related events and death, globally, from 1999 through 2018. We used data from the emergency events database of the Université Catholique de Louvain. We also categorized the countries’ income according to the World Bank GDP and we used the CO(2) emission levels data from the Carbon Dioxide Information Analysis Center to link the GDP and CO(2) emissions to years of extreme weather conditions in each country. We conducted descriptive and Poisson Regression analysis to analyze the data. A total of 77 countries reported 425 extreme weather-related events from1999 through 2018. Mortality related events were highest in middle-income countries due to severe winter conditions (N = 2,020) and cold-waves (N = 70,972). The total number of recorded deaths due to heat waves was highest in high-income countries (N = 84,344). Furthermore, the number of deaths in high-income countries, compared to low-income countries, was five-fold higher (IRR 5.18; 95%CI 4.58; 5.85, p < 0.001). The mortality rate in heat season was almost seven-fold higher than that in cold/severe winter (IRR 33.43; 95%CI 32.85; 34.02, p < 0.001). The number of deaths increased significantly with the repetition of extreme events (IRR 6.82; 95%CI 6.68; 6.96, p < 0.001). We found the number of deaths increased in high-income countries, and this was associated with an increase in the number of times extreme events occurred per year and with heat wave.
The frequency and duration of extreme temperature events continues to increase worldwide. However, the scale of population exposure and its quantitative relationship with health risks remains unknown on a global scale, limiting our ability to identify policy priorities in response to climate change. Based on data from 171 countries between 2010 and 2019, this study estimated the exposure of vulnerable populations to extreme temperatures, and their contemporary and lag associations with disease burden attributed to non-optimal temperatures. Fixed-effects models and dynamic panel models were applied. Increased vulnerable population exposure to extreme temperatures had adverse contemporary effects on the burden of disease attributed to non-optimal temperature. Health risks stemming from extreme cold could accumulate to a greater extent, exhibiting a larger lag effect. Population exposure to extreme cold was mainly distributed in high-income countries, while extreme heat occurred more in low-income and middle-income countries. However, the association between population exposure to extreme cold and burden of disease was much stronger in low-income and middle-income countries than in high-income countries, whereas the effect size of population exposure to extreme heat was similar. Our study highlighted that differential strategies should be determined and implemented according to the characteristics in different countries.
Workplace hazards and accidents occur more frequently in the construction industry than in any other industries. Occupational hazards cannot be completely eliminated but can be reduced to an extent where workers can perform activities in a safe environment. Health and safety of workers in construction site is of at most importance to employers, which when ignored can lead to fatal injuries and even death affecting the progress of work and project completion time. The goal of this study is to identify critical factors affecting workers health in extreme weather conditions and to identify the vulnerable workers based on age, gender, and ethnicity. Therefore, a questionnaire survey was developed and distributed to identify critical health challenges faced by construction workers while working in unfavorable weather conditions. The results revealed that workers with pre-existing medical condition like hyper-tension face higher unfavorable impacts on their health while working in extreme hot weather. Based on gender, female workers suffer from more heat related disorders compared to male workers. Based on age, workers above 50 years are more affected when working in extreme weather conditions compared to workers of other age groups. In addition, some workers reported increased irritation and distraction from work due to physical discomfort of working in unfavorable environment leading to more accidents at workplace. Moreover, some workers reported increased onset of muscle fatigue due to tight thermal clothing during cold weather conditions. Prolonged exposure to cold winds tends to distract the workers, leading to workers becoming more hallucinatory and disoriented. The results of this study will help employers and project managers to take proper actions against the unforeseen factors affecting the workers’ health and safety in the construction sites with extreme weather conditions.
BACKGROUND: Although a few studies have reported the relationship between high and low temperatures and chronic kidney disease (CKD), the global burden of CKD attributable to extreme heat and cold in recent decades remains unknown. METHODS: Based on the Global Burden of Disease Study (GBD) 2019, we obtained data on age-standardized mortality rates (ASMR) and age-standardized rates of disability-adjusted life years (ASDR) per 100 000 population of the CKD attributable to non-optimum temperatures from 1990 to 2019. The annual mean temperature of each country was used to divide each country into five climate zones (tropical, subtropical, warm-temperate, cool-temperate, and boreal). The locally weighted regression model was used to estimate the burden for different climate zones and Socio-demographic index (SDI) regions. RESULTS: In 1990, the ASMR and ASDR due to high temperature estimated -0.01 (95% UI, -0.74 to 0.44) and -0.32 (-21.66 to 12.66) per 100 000 population, respectively. In 2019, the ASMR and ASDR reached 0.10 (-0.28 to 0.38) and 2.71 (-8.07 to 10.46), respectively. The high-temperature burden increased most rapidly in tropical and low SDI regions. There were 0.99 (0.59 to 1.39) ASMR attributable to low-temperature in 1990, which increased to 1.05 (0.61-1.49) in 2019. While the ASDR due to low temperature declined from 22.03 (12.66 to 30.64) in 1990 to 20.43 (11.30 to 29.26) in 2019. Overall, the burden of CKD attributable to non-optimal temperatures has increased from 1990 to 2019. CKD due to hypertension and diabetes mellitus were the primary causes of CKD death attributable to non-optimum temperatures in 2019 with males and older adults being more susceptible to these temperatures. CONCLUSIONS: The CKD burden due to high, low, and non-optimum temperatures varies considerably by regions and countries. The burden of CKD attributable to high temperature has been increasing since 1990.
BACKGROUND AND OBJECTIVES: Although the international community collectively seeks to reduce global temperature rise to less than 1.5°C before 2100, irreversible environmental changes have already occurred, and as the planet warms, these changes will continue to occur. As we witness the effects of a warming planet on human health, it is imperative that neurologists anticipate how the epidemiology and incidence of neurologic disease may change. In this review, we organized our analysis around 3 key themes related to climate change and neurologic health: extreme weather events and temperature fluctuations, emerging neuroinfectious diseases, and pollutant impacts. Across each of these themes, we appraised and reviewed recent literature relevant to neurologic disease and practice. METHODS: Studies were identified using search terms relating to climate change, pollutants, and neurologic disease in PubMed, OVID MEDLINE, EMBASE, PsycInfo, and gray literature. Studies published between 1990 and 2022 were included if they pertained to human incidence or prevalence of disease, were in English, and were relevant to neurologic disease. RESULTS: We identified a total of 364 articles, grouped into the 3 key themes of our study: extreme weather events and temperature fluctuations (38 studies), emerging neuroinfectious diseases (37 studies), and pollutant impacts (289 studies). The included studies highlighted the relationships between neurologic symptom exacerbation and temperature variability, tick-borne infections and warming climates, and airborne pollutants and cerebrovascular disease incidence and severity. DISCUSSION: Temperature extremes and variability both associated with stroke incidence and severity, migraine headaches, hospitalization in patients with dementia, and multiple sclerosis exacerbations. Exposure to airborne pollutants, especially PM2.5 and nitrates, associated with stroke incidence and severity, headaches, dementia risk, Parkinson disease, and MS exacerbation. Climate change has demonstrably expanded favorable conditions for zoonotic diseases beyond traditional borders and poses the risk of disease in new, susceptible populations. Articles were biased toward resource-rich regions, suggesting a discordance between where research occurs and where changes are most acute. As such, 3 key priorities emerged for further study: neuroinfectious disease risk mitigation, understanding the pathophysiology of airborne pollutants on the nervous system, and methods to improve delivery of neurologic care in the face of climate-related disruptions.
Chronic obstructive pulmonary disease (COPD) is one of the greatest global public health challenges. Acute exacerbations of COPD lead to the accelerated deterioration of lung function, reduced quality of life, a higher number of hospitalizations, and increased mortality. The factor causing the exacerbation is usually an infectious agent, but the impact of environmental factors is being studied more thoroughly. Among them, meteorological factors are the least examined. Multiple studies have shown that lower temperatures during the cold season, as well as sudden temperature changes regardless of the season, have the most significant negative effect on patients with COPD. However, higher temperatures, especially during summer heatwaves, can also cause COPD exacerbation and it is expected that this will be an even more important health problem in the future considering climate changes. The effects of other meteorological factors on acute exacerbation of COPD, such as atmospheric pressure, solar radiation, rainfall, wind speed, and humidity are far less investigated and opposing results have been obtained in different studies. Thus, there is a need for further research in this area that would result in clinical recommendations and public health interventions that could decrease the global burden of COPD.
Some extreme cold events have occurred in the past few years. Human perceptual responses and cogni-tive performances when exposed to extremely cold environments could be significantly influenced. Impaired cognition can result in human errors and other cascading impacts. This paper aims to investi-gate human thermal perception and cognitive performance in an extremely cold environment in a cli-matic chamber. The study involved and exposed twelve male participants who wore protective clothing (2.16 clo) to a-20 degrees C climate chamber. Critical parameters for evaluating human perceptual response and cognitive performance, including thermal sensation vote (TSV), thermal comfort vote (TCV), mood, health symptoms, and selective attention performance, were recorded and analyzed. The results showed that the TSV did not recover to the value before the cold exposure despite the subjects being rewarmed in a neutral environment for 40 min. The participants’ TSV reached the coldest after 20-25 min. Cold exposure increased discomfort, which required more than 40 min to recover. The extre-mely cold exposure resulted in increased tension, anger, confusion, decreased depression and fatigue. Anger and confusion had a strong correlation with tension-anxiety, and the correlation was stronger after recovery. The extremely cold exposure had a sustained impact on selective attention and heart rate. The reaction speed decreased by 36%. The results could be used to form recommendations to protect workers’ health and performance when exposed to extremely cold environments. (c) 2021 Elsevier B.V. All rights reserved.
This study investigates the effect of local floor heating mats on the thermal comfort of workers in cold environments. Experiments were performed with two sizes of floor heating mats under two power input levels. Twenty subjects participated in the experiments at three air temperature conditions of 11, 13, and 15 degrees C. The participants performed three activities in the experiments: sitting, sitting + packing, and standing + packing. Subjective questionnaires were collected, including the overall thermal sensation vote (TSV), local thermal sensation of feet (TSVfeet), and thermal comfort vote (TCV). The subjects’ mean skin temperature (MST) and cochlear temperature were measured. The results show that subjects’ TSV, TSVfeet, and TCV significantly improved when using heating mats of larger size and higher power input. TSV feet increased faster than TSV. When the air temperature decreases, TSV feet should be higher to keep TSV close to neutral. Moreover, subjects’ MST and cochlear temperature also increased slightly when heating mats were adopted. Both MST and cochlear temperature were positively correlated with TSV. Heating mats also increased the subjects’ working efficiency, related to the TSV and TCV. Analysis of the vertical temperature distribution in the vicinity of the subjects showed that with heating mats, the thermal plume was enhanced, and the ambient air temperature increased slightly. Hence, local floor heating mats can effectively improve the thermal comfort and working efficiency of workers in cold environments.
Climate change and health are inextricably linked, especially the role of ambient temperature. This study aimed to analyze the non-communicable disease (NCD) burden attributable to low temperature globally, regionally, and temporally using data from the Global Burden of Disease (GBD) study 2019. Globally, in 2019, low temperature was responsible for 5.42% DALY and 7.18% death of NCDs, representing the age-standardized disability-adjusted life years (DALY) and death rates (per 100,000 population) of 359.6 (95% uncertainty intervals (UI): 306.09, 416.88) and 21.36 (95% UI:18.26, 24.74). Ischemic heart disease was the first leading cause of DALY and death resulting from low temperature, followed by stroke. However, age-standardized DALY and death rates attributable to low temperature have exhibited wide variability across regions, with the highest in Central Asia and Eastern Europe and the lowest in Caribbean and Western sub-Saharan Africa. During the study period (1990-2019), there has been a significant decrease in the burden of NCDs attributable to low temperature, but progress has been uneven across countries, whereas nations exhibiting high sociodemographic index (SDI) declined more significantly compared with low SDI nations. Notably, three nations, including Uzbekistan, Tajikistan, and Lesotho, had the maximum NCDs burden attributed to low temperature and displayed an upward trend. In conclusion, ambient low temperature contributes to substantial NCD burden with notable geographical variations.
Pronounced changes in the Arctic environment add a new potential driver of anomalous weather patterns in midlatitudes that affect billions of people. Recent studies of these Arctic/midlatitude weather linkages, however, state inconsistent conclusions. A source of uncertainty arises from the chaotic nature of the atmosphere. Thermodynamic forcing by a rapidly warming Arctic contributes to weather events through changing surface heat fluxes and large-scale temperature and pressure gradients. But internal shifts in atmospheric dynamics-the variability of the location, strength, and character of the jet stream, blocking, and stratospheric polar vortex (SPV)-obscure the direct causes and effects. It is important to understand these associated processes to differentiate Arctic-forced variability from natural variability. For example in early winter, reduced Barents/Kara Seas sea-ice coverage may reinforce existing atmospheric teleconnections between the North Atlantic/Arctic and central Asia, and affect downstream weather in East Asia. Reduced sea ice in the Chukchi Sea can amplify atmospheric ridging of high pressure near Alaska, influencing downstream weather across North America. In late winter southward displacement of the SPV, coupled to the troposphere, leads to weather extremes in Eurasia and North America. Combined tropical and sea ice conditions can modulate the variability of the SPV. Observational evidence for Arctic/midlatitude weather linkages continues to accumulate, along with understanding of connections with pre-existing climate states. Relative to natural atmospheric variability, sea-ice loss alone has played a secondary role in Arctic/midlatitude weather linkages; the full influence of Arctic amplification remains uncertain.
Heat exposure is a well-known health hazard, which causes several problems ranging from thermal discomfort or productivity reduction to the aggravation of existing illnesses and death. Climate projections foresee an increase in the frequency and intensity of heat-related impacts on human health. To reduce these climate risks, governments need a better understanding of not only the scale and the factors affecting those risks, but also how to prepare and protect the city and citizens against these risks and prevent them through effective policy making. Therefore, climate adaptation decisions need to be made in complex systems with manifold uncertainties. In response to these deep uncertainties, different planning approaches have been developed to assist policymakers in decision making. This paper is focused on one of the dynamic adaptive policy planning approaches: the adaptation pathway. This approach allows designing alternative feasible plans that are flexible and can respond when new information appears or when conditions in the environment change. This paper presents a structured methodology for designing adaptation pathways. The work describes a high-level adaptation pathway covering heatwave impacts on productivity and health at city level in Antwerp to ensure the city adapts to future conditions. Lastly, a summary is provided of the lessons learned and the challenges of this approach are discussed.
The negative cardiorespiratory health outcomes due to extreme temperatures and air pollution are widely studied, but knowledge about the effectiveness of the implementation of adaptive mechanisms remains unclear. The objective of this paper is to explore the evidence of adaptive mechanisms for cardiorespiratory diseases regarding extreme temperatures and air pollution by comparing the results of two systematic literature review (SLR) processes sharing the same initial research question but led by two research groups with different academic backgrounds working in the same multidisciplinary team. We start by presenting the methodological procedures and the results of the SLR triggered by the research group mainly composed by researchers with a background in geography (named geographical strategy). We then compare these results with those achieved in the SLR led by the research group with a background in epidemiology (named epidemiological strategy). Both SLR were developed under the EU Horizon 2020 Project “EXHAUSTION “. The results showed: 1) the lack of evidence regarding the effectiveness of adaptation measures, namely due to the limited number of studies about the topic, the preponderance of studies dedicated to heat extremes or the unbalance between different adaptation measures; 2) that the choice of search terms in the geographical strategy, despite being more comprehensive at first sight, ended up retrieving less results, but it brought new studies that can complement the results of the epidemiological strategy. Therefore, it is suggested that to strengthen the empirical evidence of the effectiveness of adaptation measures, powerful multidisciplinary teams should work together in the preparation of SLR in topics of great complexity, such as the one presented in this paper.
OBJECTIVE: We conducted a systematic review of the published literature to test the hypothesis that maternal exposure to extremes of ambient temperatures during pregnancy is associated with the risk for psychiatric disorders or congenital malformations in offspring, both of which are indicative of perturbations of fetal neurodevelopment. METHOD: This study was conducted in accordance with the recommendations outlined in the Meta-analysis of Observational Studies in Epidemiology (MOOSE) reporting proposal. Electronic databases (Ovid MEDLINE, Ovid Embase, Ovid PsycINFO, Ovid Global Health, Web of Science, and Cochrane Library) were searched. Four independent reviewers selected studies with the following criteria: (1) prenatal maternal ambient temperature exposure; (2) outcome of offspring psychiatric disorder or congenital defects; (3) empirical study; (4) full-length article, no conference presentations or abstracts. RESULTS: Twenty-two studies met criteria and one was added from a reference list (n = 23). Of these, schizophrenia (n = 5), anorexia nervosa (n = 3) and congenital cardiovascular malformations (n = 6) studies were the most common. Each of these categories showed some evidence of association with an early pregnancy maternal ambient heat exposure effect, with other evidence for a late pregnancy cold effect. CONCLUSION: Some evidence supports a role for early pregnancy maternal exposure to extreme ambient heat in the development of psychiatric disorders, but large-scale, prospective cohort data on individual births is essential. Optimal studies will be conducted in seasonally variable climates, accounting for actual maternal residence over the pregnancy and at parturition, local environmental temperature records, and appropriate covariates, similar to studies identified by this systematic review for congenital malformations.
Aedes aegypti and Aedes albopictus transmit diseases such as dengue, and are of major public health concern. Driven by climate change and global trade/travel both species have recently spread to new tropic/subtropic regions and Ae. albopictus also to temperate ecoregions. The capacity of both species to adapt to new environments depends on their ecophysiological plasticity, which is the width of functional niches where a species can survive. Mechanistic distribution models often neglect to incorporate ecophysiological plasticity especially in regards to overwintering capacity in cooler habitats. To portray the ecophysiological plasticity concerning overwintering capability, we conducted temperature experiments with multiple populations of both species originating from an altitudinal gradient in South Asia and tested as follows: the cold tolerance of eggs (-2 °C- 8 days and – 6 °C- 2 days) without and with an experimental winter onset (acclimation: 10 °C- 60 days), differences between a South Asian and a European Ae. albopictus population and the temperature response in life cycles (13 °C, 18 °C, 23 °C, 28 °C). Ecophysiological plasticity in overwintering capacity in Ae. aegypti is high in populations originating from low altitude and in Ae. albopictus populations from high altitude. Overall, ecophysiological plasticity is higher in Ae. albopictus compared to Ae. aegypti. In both species acclimation and in Ae. albopictus temperate continental origin had a huge positive effect on survival. Our results indicate that future mechanistic prediction models can include data on winter survivorship of both, tropic and subtropic Ae. aegypti, whereas for Ae. albopictus this depends on the respective temperate, tropical region the model is focusing on. Future research should address cold tolerance in multiple populations worldwide to evaluate the full potential of the ecophysiological plasticity in the two species. Furthermore, we found that Ae. aegypti can survive winter cold especially when acclimated and will probably further spread to colder ecoregions driven by climate change.
Exposures to ambient fine particulate matter (PM(2.5)) and cold ambient temperatures have been identified as important risk factors in contributing towards the global mortality from chronic obstructive pulmonary disease (COPD). Despite China currently being the country with the largest population in the world, previous relative risk (RR) models have considered little or no information from the ambient air pollution related cohort studies in the country. This likely provides a less accurate picture of the trend in air pollution attributable mortality in the country over time. A novel relative risk model called pollutant-temperature exposure (PTE) model is proposed to estimate the RR attributable to the combined effect of air pollution and ambient temperature in a population. In this paper, the pollutant concentration-response curve was extrapolated from the cohort studies in China, whereas the temperature response curve was extracted from a study in Yangtze River Delta (YRD) region. The performance of the PTE model was compared with the integrated exposure-response (IER) model using the data of YRD region, which revealed that the estimated relative risks of the PTE model were noticeably higher than the IER model during the winter season. Furthermore, the predictive ability of the PTE model was validated using actual data of Ningbo city, which showed that the estimated RR using the PTE model with 1-month moving average data showed a good result with the trend of actual COPD mortality, indicated by a lower root mean square error (RMSE = 0.956). By considering the combined effect of ambient air pollutant and ambient temperature, the PTE model is expected to provide more accurate relative risk estimates for the regions with high levels of ambient PM(2.5) and seasonal variation of ambient temperature.
The study deals with an assessment and interpretation of the bioclimatic conditions in Vranje (southern Serbia). The study aims at temporal distributions of bioclimatic conditions focussing on extreme thermal stress based on the Universal Thermal Climate Index (UTCI). The meteorological data required for the calculation of UTCI concern hourly (7 and 14 CET) weather data collected for the period 2000-2017. The frequency of very strong heat stress (VSHS), very strong cold stress (VSCS) and extreme cold stress (ECS) for both morning and midday hours. Furthermore, the daily difference of the UTCI hourly values (diurnal UTCI change) are specified, giving the daily variance of heat and cold stress. The results revealed the frequency of days in which thermal stress prevails for the studied period. The obtained results show an increase in extreme heat biothermal conditions, while extreme cold biothermal conditions are in decline, especially in the last 10 years. However, the frequency (the number of days) of very strong heat stress (VSHS) increased since 2007. A spectacular increase in heat stress was observed in the month of September, particularly in 2015.
BACKGROUND: Because older adults are particularly vulnerable to nonoptimal temperatures, it is expected that the progressive population aging will amplify the health burden attributable to heat and cold due to climate change in future decades. However, limited evidence exists on the contribution of population aging on historical temperature-mortality trends. OBJECTIVES: We aimed to a) assess trends in heat- and cold-related mortality in Switzerland between 1969 and 2017 and b) to quantify the contribution of population aging to the observed patterns. METHODS: We collected daily time series of all-cause mortality by age group ( < 65, 65-79, and 80 y and older) and mean temperature for each Swiss municipality (1969-2017). We performed a two-stage time-series analysis with distributed lag nonlinear models and multivariate longitudinal meta-regression to obtain temperature-mortality associations by canton, decade, and age group. We then calculated the corresponding excess mortality attributable to nonoptimal temperatures and compared it to the estimates obtained in a hypothetical scenario of no population aging. RESULTS: Between 1969 and 2017, heat- and cold-related mortality represented 0.28% [95% confidence interval (CI): 0.18, 0.37] and 8.91% (95% CI: 7.46, 10.21) of total mortality, which corresponded to 2.4 and 77 deaths per 100,000 people annually, respectively. Although mortality rates for heat slightly increased over time, annual number of deaths substantially raised up from 74 (12;125) to 181 (39;307) between 1969-78 and 2009-17, mostly driven by the ≥ 80-y-old age group. Cold-related mortality rates decreased across all ages, but annual cold-related deaths still increased among the ≥ 80, due to the increase in the population at risk. We estimated that heat- and cold-related deaths would have been 52.7% and 44.6% lower, respectively, in the most recent decade in the absence of population aging. DISCUSSION: Our findings suggest that a substantial proportion of historical temperature-related impacts can be attributed to population aging. We found that population aging has attenuated the decrease in cold-related mortality and amplified heat-related mortality. https://doi.org/10.1289/EHP9835.
This study tries to solve some issues in the construction sector related to Sustainable Development Goals (SDG) numbers 3 (health and well-being) and 8 (decent work and economic growth) of the 2030 Agenda, improving the working conditions of workers in the construction sector, at certain latitudes, since they are constantly exposed to inclement weather conditions and their safety may be adversely affected. Therefore, a design of a new procedure for the installation of a panel-based facade is proposed, which allows the complete closing of the building during its execution and thus improves the comfort and safety of workers. In addition to the constructive definition of the proposed system, its implementation procedure and the energy consumption during the interior air conditioning phase are analyzed. In addition, a comparative study of execution times between the proposed procedure and a conventional solution is performed. The conclusions of the study highlight that the proposed system improves: the working conditions in extreme climates and prevents risks derived from work in extreme weather conditions; the precision in the formation of window and door openings and their coordination with the modular facades; the ease of execution and delays the placement of the exterior scaffolding. Overall, the proposed procedure reduces the weight of the facade and the thermal transmittance by 13.5% and reduces not only costs due to the modulation of the system, but also execution times in the facade and interior work phases (around 40%) and the structure phase (around 32%).
Climate change is producing more extremes and increasing the number and magnitude of risks that impact people’s lives, so identifying and understanding local climate risks is a long but essential process for defining adaptation strategies. The availability of technologies to sensitize and educate people about risks, and to assist people with becoming active observers and monitors of climatic elements has helped to promote permanent surveillance and proactive attitudes towards climatic phenomena that lead to undesirable risks. This paper proposes a methodological approach to guide citizens moving around the city when extreme temperatures occur, minimizing climatic risks and negative health comes, using a very simple method based on Landsat 8 temperature data images at a subsection spatial scale level. The results obtained indicate the places of higher extreme temperatures risks, as well as some of the potential places that people can use to protect themselves. This work demonstrates the value of mapping climatic factors at a local scale and deliver tailored and accurate maps with the places suitable for alleviating bioclimatic stresses and the places that should be avoided.
This paper describes the functional development of the ClimApp tool (available for free on iOS and Android devices), which combines current and 24 h weather forecasting with individual information to offer personalised guidance related to thermal exposure. Heat and cold stress assessments are based on ISO standards and thermal models where environmental settings and personal factors are integrated into the ClimApp index ranging from -4 (extremely cold) to +4 (extremely hot), while a range of -1 and +1 signifies low thermal stress. Advice for individuals or for groups is available, and the user can customise the model input according to their personal situation, including activity level, clothing, body characteristics, heat acclimatisation, indoor or outdoor situation, and geographical location. ClimApp output consists of a weather summary, a brief assessment of the thermal situation, and a thermal stress warning. Advice is provided via infographics and text depending on the user profile. ClimApp is available in 10 languages: English, Danish, Dutch, Swedish, Norwegian, Hellenic (Greek), Italian, German, Spanish and French. The tool also includes a research functionality providing a platform for worker and citizen science projects to collect individual data on physical thermal strain and the experienced thermal strain. The application may therefore improve the translation of heat and cold risk assessments and guidance for subpopulations. ClimApp provides the framework for personalising and downscaling weather reports, alerts and advice at the personal level, based on GPS location and adjustable input of individual factors.
BACKGROUND: Europe has emerged as a major climate change hotspot, both in terms of an increase in seasonal averages and climate extremes. Projections of temperature-attributable mortality, however, have not been comprehensively reported for an extensive part of the continent. Therefore, we aim to estimate the future effect of climate change on temperature-attributable mortality across Europe. METHODS: We did a time series analysis study. We derived temperature-mortality associations by collecting daily temperature and all-cause mortality records of both urban and rural areas for the observational period between 1998 and 2012 from 147 regions in 16 European countries. We estimated the location-specific temperature-mortality relationships by using standard time series quasi-Poisson regression in conjunction with a distributed lag non-linear model. These associations were used to transform the daily temperature simulations from the climate models in the historical period (1971-2005) and scenario period (2006-2099) into projections of temperature-attributable mortality. We combined the resulting risk functions with daily time series of future temperatures simulated by four climate models (ie, GFDL-ESM2M, HadGEM2-ES, IPSL-CM5A-LR, and MIROC5) under three greenhouse gas emission scenarios (ie, Representative Concentration Pathway [RCP]2.6, RCP6.0, and RCP8.5), providing projections of future mortality attributable fraction due to moderate and extreme cold and heat temperatures. FINDINGS: Overall, 7·17% (95% CI 5·81-8·50) of deaths registered in the observational period were attributed to non-optimal temperatures, cold being more harmful than heat by a factor of ten (6·51% [95% CI 5·14-7·80] vs 0·65% [0·40-0·89]), and with large regional differences across countries-eg, ranging from 4·85% (95% CI 3·75-6·00) in Germany to 9·87% (8·53-11·19) in Italy. The projection of temperature anomalies by RCP scenario depicts a progressive increase in temperatures, more exacerbated in the high-emission scenario RCP8.5 (4·54°C by 2070-2099) than in RCP6.0 (2·89°C) and RCP2.6 (1·67°C). This increase in temperatures was transformed into attributable fraction. Projections consistently indicated that the increase in heat attributable fraction will start to exceed the reduction of cold attributable fraction in the second half of the 21st century, especially in the Mediterranean and in the higher emission scenarios. The comparison between scenarios highlighted the important role of mitigation, given that the total attributable fraction will only remain stable in RCP2.6, whereas the total attributable fraction will rapidly start to increase in RCP6.0 by the end of the century and in RCP8.5 already by the middle of the century. INTERPRETATION: The increase in heat attributable fraction will start to exceed the reduction of cold attributable fraction in the second half of the 21st century. This finding highlights the importance of implementing mitigation policies. These measures would be especially beneficial in the Mediterranean, where the high vulnerability to heat will lead to an imbalance between the decreasing cold and increasing heat-attributable mortality. FUNDING: None.
This study was focused on the metropolitan area of Florence in Tuscany (Italy) with the aim to provide a functional spatial thermal anomaly indicator obtained throughout a thermal summer and winter hot-spot detection. The hot-spot analysis was performed by applying Getis-Ord Gi* spatial statistics to Land Surface Temperature (LST) layers, obtained from Landsat 8 remote sensing data during the 2015-2019 daytime summer and winter period, to delimitate summer hot- and cool-spots, and winter warm- and cold-spots. Further, these ones were spatially combined thus obtaining a comprehensive summer-winter Thermal Hot-Spot (THS(SW)) spatial indicator. Winter and summer mean daily thermal comfort profiles were provided for the study area assessing the Universal Thermal Climate Index (UTCI) by using meteorological data available from seven local weather stations, located at a maximum distance of 350 m from industrial sites. A specific focus on industrial sites was carried out by analyzing the industrial buildings characteristics and their surrounding areas (50 m buffer), through the following layers: industrial building area (BA), surface albedo of buildings (ALB), impervious area (IA), tree cover (TC), and grassland area (GA). The novel THS(SW) classification applied to industrial buildings has shown that about 50% of the buildings were located in areas characterized by summer hot-spots. Increases in BA and IA revealed warming effects on industrial buildings, whereas increases in ALB, TC, and GA disclosed cooling effects. A decrease of about 10% of IA replaced by TC and GA was associated with about 2 °C decrease of LST. Very strong outdoor heat stress conditions were observed during summer daytime, whereas moderate winter outdoor cold stress conditions were recorded during nighttime until the early morning. The thermal spatial hot-spot classification in industrial areas provides a very useful source of information for thermal mitigation strategies aimed to reduce the heat-related health risk for workers.
Bioclimatic comfort is the state of people in which they feel comfortable, happy, and fit in the atmospheric environment they are. The bioclimatic comfort conditions of cities have changed depending on anthropogenic factors. The aim of this study is to compare the bioclimatic comfort conditions of Usak city between 1990 and 2018. In the first stage, the bioclimatic comfort conditions of the city centre between 1990 and 2018 were determined according to the Physiological Equivalent Temperature (PET) index obtained from the RayMan model by using hourly data of the meteorological station in the city centre; air temperature (degrees C), relative humidity (%), wind velocity(m/s) and cloudiness (octa). By using Geographic Information Systems in the spatial distribution of bioclimatic comfort conditions, calculations were made with base maps of elevation, land use, solar radiation, mean radiant temperature (MRT), and wind speed. In the second stage, the land cover was classified according to the general appearance for the period covering 28 years (from 1990 to 2018), and the rates of change were calculated. As a result, it was determined that the most comfortable areas are the agricultural areas, followed by the forest and natural areas, and the most uncomfortable conditions are in the artificial areas. Intense urbanization and construction have increased the uncomfortable conditions in the city. It is thought that the plans to be made by prioritizing bioclimatic comfort conditions will contribute to decelerating the climate change caused by global warming, as well as improving the existing problems.
The thermal conditions that prevail in cities pose a number of challenges to urban residents and policy makers related to quality of life, health and welfare as well as to sustainable urban development. However, the changes in thermal stress due to climate change are probably not uniform among cities with different background climates. In this work, a comparative analysis of observed and projected thermal stress (cold stress, heat stress, no thermal stress) across four European cities (Helsinki, Rotterdam, Vienna, and Athens), which are representative of different geographical and climatic regions of the continent, for a recent period (1975 - 2004) and two future periods (2029 - 2058, 2069 - 2098) has been conducted. Applying a rational thermal index (Universal Thermal Climate Index) and considering two models of the EURO-CORDEX experiment (RCA4-MOHC, RCA4-MPI) under two Representative Concentration Pathways (RCP4.5, RCP8.5), the projected future changes in thermal conditions are inspected. The distribution of thermal stress in the current climate varies greatly between the cities, reflecting their climatic and urban heterogeneity. In the future climate, a reduction in the frequency of cold stress is expected across all cities, ranging between - 2.9% and - 16.2%. The projected increase in the frequency of optimal thermal conditions increases with increasing latitude, while the projected increase in the frequency of heat stress (ranging from + 0.2 to + 14.6%) decreases with increasing latitudes. Asymmetrical changes in cold- and heat-related stress between cities were found to affect the annual percentage of optimal (no thermal stress) conditions in future. Although future projections are expected to partly bridge the gap between the less-privileged cities (with respect to annual frequency of optimal thermal conditions) like Helsinki and Rotterdam and the more privileged ones like Athens, the former will still lag behind on an annual basis.
The aim of the article was to present the influence of the external environment on people working on scaffolding. For this purpose, the heat load of a man was determined using the universal thermal climate index. The research was carried out on 40 facade scaffolds located in four voivodeships in Poland: Lower Silesia, Lublin, Lodzkie, and Masovian. The conducted analysis showed that employees may experience strong or very strong heat stress, and also extreme heat stress in isolated cases. The highest probability at 0.30 level occurs on scaffolds located in the Lodzkie voivodeship. Environmental conditions are therefore unfavourable for people working outside. This can lead to reduced concentration, longer reaction time, and greater fatigue, contributing to an increase in situations that could lead to accidents. Hazard identification allows to take safety measures that improve the comfort of work on scaffolding.
Exposure to heat has a range of potential negative impacts on human health; hot weather may exacerbate cardiovascular and respiratory illness or lead to heat stroke and death. Urban populations are at increased risk due to the Urban Heat Island (UHI) effect (higher urban temperatures compared with rural ones). This has led to extensive investigation of the summertime UHI and its effects, whereas far less research focuses on the wintertime UHI. Exposure to low temperature also leads to a range of illnesses, and in fact, in the UK, annual cold-related mortality outweighs heat-related mortality. It is not clearly understood to what extent the wintertime UHI may protect against cold related mortality. In this study we quantify the UHI intensity in wintertime for a heavily urbanized UK region (West Midlands, including Birmingham) using a regional weather model, and for the first time, use a health impact assessment (HIA) to estimate the associated impact on cold-related mortality. We show that the population-weighted mean winter UHI intensity was +2.3 °C in Birmingham city center, and comparable with that of summer. Our results suggest a potential protective effect of the wintertime UHI, equivalent to 266 cold-related deaths avoided (~15% of total cold-related mortality over ~11 weeks). When including the impacts of climate change, our results suggest that the number of heat-related deaths associated with the summer UHI will increase from 96 (in 2006) to 221 in the 2080s, based on the RCP8.5 emissions pathway. The protective effect of the wintertime UHI is projected to increase only slightly from 266 cold-related deaths avoided in 2009 to 280 avoided in the 2080s. The different effects of the UHI in winter and summer should be considered when assessing interventions in the built environment for reducing summer urban heat, and our results suggest that the future burden of temperature-related mortality associated with the UHI is likely to increase in summer relative to winter.
Air temperature has been the most commonly used exposure metric in assessing relationships between thermal stress and mortality. Lack of the high-quality meteorological station data necessary to adequately characterize the thermal environment has been one of the main limitations for the use of more complex thermal indices. Global climate reanalyses may provide an ideal platform to overcome this limitation and define complex heat and cold stress conditions anywhere in the world. In this study, we explored the potential of the Universal Thermal Climate Index (UTCI) based on ERA5 – the latest global climate reanalysis from the European Centre for Medium-Range Weather Forecasts (ECMWF) – as a health-related tool. Employing a novel ERA5-based thermal comfort dataset ERA5-HEAT, we investigated the relationships between the UTCI and daily mortality data in 21 cities across 9 European countries. We used distributed lag nonlinear models to assess exposure-response relationships between mortality and thermal conditions in individual cities. We then employed meta-regression models to pool the results for each city into four groups according to climate zone. To evaluate the performance of ERA5-based UTCI, we compared its effects on mortality with those for the station-based UTCI data. In order to assess the additional effect of the UTCI, the performance of ERA5-and station-based air temperature (T) was evaluated. Whilst generally similar heat- and cold-effects were observed for the ERA5-and station-based data in most locations, the important role of wind in the UTCI appeared in the results. The largest difference between any two datasets was found in the Southern European group of cities, where the relative risk of mortality at the 1st percentile of daily mean temperature distribution (1.29 and 1.30 according to the ERA5 vs station data, respectively) considerably exceeded the one for the daily mean UTCI (1.19 vs 1.22). These differences were mainly due to the effect of wind in the cold tail of the UTCI distribution. The comparison of exposure-response relationships between ERA5-and station-based data shows that ERA5-based UTCI may be a useful tool for definition of life-threatening thermal conditions in locations where high-quality station data are not available.
Few studies have used empirical evidence of past adaptation to project temperature-related excess mortality under climate change. Here, we assess adaptation in future projections of temperature-related excess mortality by employing evidence of shifting minimum mortality temperatures (MMTs) concurrent with climate warming of recent decades. The study is based on daily non-external mortality and daily mean temperature time-series from 11 Spanish cities covering four decades (1978-2017). It employs distributed lag non-linear models (DLNMs) to describe temperature-mortality associations, and multivariate mixed-effect meta-regression models to derive city- and subperiod-specific MMTs, and subsequently MMT associations with climatic indicators. We use temperature projections for one low- and one high-emission scenario (ssp126, ssp370) derived from five global climate models. Our results show that MMTs have closely tracked mean summer temperatures (MSTs) over time and space, with meta-regression models suggesting that the MMTs increased by 0.73 degrees C (95%CI: 0.65, 0.80) per 1 degrees C rise in MST over time, and by 0.84 degrees C (95%CI: 0.76, 0.92) per 1 degrees C rise in MST across cities. Future projections, which include adaptation by shifting MMTs according to observed temporal changes, result in 63.5% (95%CI: 50.0, 81.2) lower heat-related excess mortality, 63.7% (95%CI: 30.2, 166.7) higher cold-related excess mortality, and 11.2% (95%CI: -5.5, 39.5) lower total temperature-related excess mortality in the 2090s for ssp370 compared to estimates that do not account for adaptation. For ssp126, assumptions on adaptation have a comparatively small impact on excess mortality estimates. Elucidating the adaptive capacities of societies can motivate strengthened efforts to implement specific adaptation measures directed at reducing heat stress under climate change.
Aim To determine the relationship between seasonal changes in ambient temperature, humidity and general and specific mortality rates in the area of Zenica-Doboj Canton. Methods Changes in the average monthly mortality in the period from 2008 to 2019 were analysed (linear regression) in relation to the average temperatures and humidity in those months in the same time period in Zenica-Doboj Canton. Results Overall mortality increased from 7.9 ‰ in 2008 to 10.2 ‰ in 2019. Overall and specific mortality rates for cardiovascular, malignant, respiratory and metabolic diseases followed seasonal change of ambient temperature and humidity. The monitoring trend showed strong determination degree for overall mortality and mortality for cardiovascular, malignant and respiratory diseases, while for metabolic diseases it was somewhat lower. The highest mortality rates were found in January (cold month), and in August (warm month); the lowest one was in May, September and October. There was a strong significant negative correlation between temperature and mortality rates, while the correlation between humidity and mortality rates was not significant. Conclusion As we have proven that mortality rates followed seasonal changes in ambient temperature and determined months with the least mortality rate, the community must take measures to ensure microclimatic conditions for the survival of patients with cardiovascular, malignant, respiratory and metabolic diseases.
Climate change means the UK will experience warmer winters and hotter summers in the future. Concurrent energy efficiency improvements to housing may modify indoor exposures to heat or cold, while population aging may increase susceptibility to temperature-related mortality. We estimate heat and cold mortality and energy consumption in London for typical (non-extreme) future climates, given projected changes in population and housing. Building physics models are used to simulate summertime and wintertime indoor temperatures and space heating energy consumption of London dwellings for ‘baseline’ (2005-2014) and future (2030s, 2050s) periods using data from the English Housing Survey, historical weather data, and projected future weather data with temperatures representative of ‘typical’ years. Linking to population projections, we calculate future heat and cold attributable mortality and energy consumption with demolition, construction, and alternative scenarios of energy efficiency retrofit. At current retrofit rates, around 168-174 annual cold-related deaths per million population would typ-ically be avoided by the 2050s, or 261-269 deaths per million under ambitious retrofit rates. Annual heat deaths would typically increase by 1 per million per year under the current retrofit rate, and 12-13 per million under ambitious rates without population adaptation to heat. During typical future summers, an estimated 38-73% of heat-related deaths can be avoided using external shutters on windows, with their effectiveness lower during hotter weather. Despite warmer winters, ambitious retrofit rates are nec-essary to reduce typical annual energy consumption for heating below baseline levels, assuming no improvement in heating system efficiencies. Concerns over future overheating in energy efficient housing are valid but increases in heat attributable mortality during typical and hot (but not extreme) summers are more than offset by significant reductions in cold mortality and easily mitigated using passive mea-sures. More ambitious retrofit rates are critical to reduce energy consumption and offer co-benefits for reducing cold-related mortality. (c) 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).
Periods of extremely hot and cold weather can cause significant mortality and morbidity in both temperate and more extreme climates. In the UK, their occurrence prompts the issuing of number and colour coded warnings providing an assessment of the level of risk. These are designed to minimize health impact by prompting timely and appropriate mitigating actions by the public. Drawing upon the interdisciplinary notion of framing, I report on a study that identified a central role for language in mediating how these warnings are interpreted and evaluated. I use an innovative approach that combines the quantitative tools of corpus linguistics to identify the language used to represent warnings and the risks of extreme temperature in the mass media, with qualitative analysis of focus group discussions of typical texts. A comparison of both datasets indicates a multi-layered interactivity between the myriad ways in which language can give salience to aspects of a risk scenario and an interpreter’s knowledge and perception of a threat, and that underlying such interactions, is the conceptualization of risk as scalar property.
During the last decades the effects of thermal stress on public health have been a great concern worldwide. Thermal stress is determined by air temperature in combination with other meteorological parameters, such as relative humidity and wind speed. The present study is focused on the Mediterranean city of Thessaloniki, Greece and it aims to explore the association between thermal stress and mortality from cardiovascular diseases, using both air temperature and other thermal indices as indicators. For that, an over-dispersed Poisson regression function was used, in combination with distributed lag non-linear models, in order to capture the delayed and nonlinear effects of temperature. Our results revealed a reverse J-shaped exposure-response curve for the total population and females and a U-shaped association for males. In all cases examined, the minimum mortality temperature was identified around the 80th percentile of each distribution. It is noteworthy that despite the fact that the highest risks of cardiovascular mortality were estimated for exposure to extreme temperatures, moderate temperatures were found to cause the highest burden of mortality. On the whole, our estimations demonstrated that the population in Thessaloniki is more susceptible to cold effects and in regard with gender, females seem to be more vulnerable to ambient thermal conditions.
Climate change poses an unprecedented challenge to population health and health systems’ resilience, with increasing fluctuations in extreme temperatures through pressures on hospital capacity. While earlier studies have estimated morbidity attributable to hot or cold weather across cities, we provide the first large-scale, population-wide assessment of extreme temperatures on inequalities in excess emergency hospital admissions in England. We used the universe of emergency hospital admissions between 2001 and 2012 combined with meteorological data to exploit daily variation in temperature experienced by hospitals (N = 29,371,084). We used a distributed lag model with multiple fixed-effects, controlling for seasonal factors, to examine hospitalisation effects across temperature-sensitive diseases, and further heterogeneous impacts across age and deprivation. We identified larger hospitalisation impacts associated with extreme cold temperatures than with extreme hot temperatures. The less extreme temperatures produce admission patterns like their extreme counterparts, but at lower magnitudes. Results also showed an increase in admissions with extreme temperatures that were more prominent among older and socioeconomically-deprived populations – particularly across admissions for metabolic diseases and injuries.
BACKGROUND: Ambient temperature, particularly heat, is increasingly acknowledged as a trigger for preterm delivery but study designs have been limited and results mixed. We aimed to comprehensively evaluate the association between ambient temperature throughout pregnancy and preterm delivery. METHODS: We estimated daily temperature throughout pregnancy using a cutting-edge spatiotemporal model for 5347 live singleton births from three prospective cohorts in France, 2002-2018. We performed Cox regression (survival analysis) with distributed lags to evaluate time-varying associations with preterm birth simultaneously controlling for exposure during the first 26 weeks and last 30 days of pregnancy. We examined weekly mean, daytime, night-time and variability of temperature, and heatwaves accounting for adaptation to location and season. RESULTS: Preterm birth risk was higher following cold (5th vs 50th percentile of mean temperature) 7-9 weeks after conception [relative risk (RR): 1.3, 95% CI: 1.0-1.6 for 2°C vs 11.6°C] and 10-4 days before delivery (RR: 1.6, 95% CI: 1.1-2.1 for 1.2°C vs 12.1°C). Night-time heat (95th vs 50th percentile of minimum temperature; 15.7°C vs 7.4°C) increased risk when exposure occurred within 5 weeks of conception (RR: 2.0, 95% CI: 1.05-3.8) or 20-26 weeks after conception (RR: 2.9, 95% CI: 1.2-6.8). Overall and daytime heat (high mean and maximum temperature) showed consistent effects. We found no clear associations with temperature variability or heatwave indicators, suggesting they may be less relevant for preterm birth. CONCLUSIONS: In a temperate climate, night-time heat and chronic and acute cold exposures were associated with increased risk of preterm birth. These results suggest night-time heat as a relevant indicator. In the context of rising temperatures and more frequent weather hazards, these results should inform public health policies to reduce the growing burden of preterm births.
There is only limited scientific evidence with varying results on the association between hospital admissions and low ambient temperatures. Furthermore, there has been no research in Northern Europe on cold-associated morbidity. Therefore, this study investigated the associations of daily wintertime temperature and cold spells with cardiorespiratory hospital admissions in the Helsinki metropolitan area, Finland. Daily number of non-elective hospital admissions for 2001-2017 was obtained from the national hospital discharge register and meteorological data from the Finnish Meteorological Institute. Quasi-Poisson regression models were fitted, controlling for potential confounders such as time trend, weekday, holidays, air pollution, barometric pressure, and influenza. The associations of cold season daily mean ambient temperature and cold spells with hospital admissions were estimated using a penalized distributed lag linear models with 21 lag days. Decreased wintertime ambient temperature was associated with an increased risk of hospitalization for myocardial infarction in the whole population (relative risk [RR] per 1 degrees C decrease in temperature: 1.017, 95% confidence interval [CI]: 1.002-1.032). An increased risk of hospital admission for respiratory diseases (RR: 1.012, 95% CI: 1.002, 1.022) and chronic obstructive pulmonary disease (RR: 1.031, 95% CI: 1.006, 1.056) was observed only in the >= 75 years age group. There was an independent effect of cold spell days only for asthma admissions (RR: 2.348, 95% CI: 1.026, 5.372) in the all-ages group. Cold temperature increases the need for acute hospital care due to myocardial infarction and respiratory causes during winter in a northern climate.
BACKGROUND: A positive correlation between T1DM onset and winter has been suggested by several studies. We investigated the seasonal variation of T1DM diagnosis and epidemiological parameters in children from Western Greece with T1DM. METHODS: One hundred and five patients, 44 males, aged 1-16 years were studied. The month of the diagnosis, the order of birth, gestational age, birth weight, the mode of delivery, parental age and pubertal status were recorded from the patients’ files. RESULTS: The mean age at diagnosis was 8.1 ± 4.0 years. The majority of the studied patients were diagnosed during the period of October-March. The majority were born at full term, 11.7% were preterm babies and 52.3% were first born. The mean birth weight was 3266 ± 596 g. 60% were born by vaginal delivery. The majority of the patients were prepubertal at diagnosis. CONCLUSIONS: Our results are in agreement with the reported seasonal variation of T1DM onset in other regions of Greece and Europe. The positive correlation between T1DM presentation and colder temperatures may be explained by factors such as viral infections. This is the first report on epidemiological parameters that may be related to T1DM presentation in Western Greece. The study of such parameters extends the understanding on the disease as a whole. IMPACT: A seasonality of the T1DM diagnosis is shown, with a predominance of the colder months of the year. This is in agreement with previous reports from other countries. Our findings confirm previously reported data and add to the existing knowledge on T1DM in general. Additionally, this is one of the few reports on the incidence and epidemiology of T1DM in Greece and the first in the region of Western Greece. Safer and more accurate conclusions can be drawn with regards to the possible causes and predisposing factors of T1DM by the assessment of statistical data from different populations throughout the world. This offers a better understanding of T1DM and may also contribute to the identification of factors that may reduce the incidence of the disease in the future.
Background While many studies analyze the effect of extreme thermal events on health, little has been written about the effects of extreme cold on mortality. This scarcity of papers is particularly relevant when we search studies about extreme cold on the health of rural population. Therefore, we tried to analyze the effect of cold waves on urban areas and rural areas from Madrid and to test whether differentiated effects exist between both population classes. For this purpose, we analyzed data from the municipalities with over 10,000 inhabitants for the period from January 1, 2000 through December 31, 2013. Municipalities were classified as urban or rural (Eurostat), and they were grouped into similar climatological zones: Urban Metropolitan Centre (UMC), Rural Northern Mountains (RNM), Rural Centre (RC) and Southern Rural (SR). The dependent variable was the daily mortality rate due to natural causes per million inhabitants (CIE-X: A00-R99) that occurred between the months of November and March for the period. The independent variable was minimum daily temperature (oC) (T-min). Social and demographic contextual variables were used, including: population > age 64 (%), deprivation index and housing indicators. The analysis was carried out in three phases: (1) determination of the threshold temperature (T-threshold) which defines the cold waves; (2) determination of the relative risk (RR) for cold waves using Poisson linear regression (GLM); and (3) using GLM of the binomial family, Odds Ratios (OR) were calculated to analyze the relationship between the frequency of the appearance of cold waves and the socioeconomic variables. Results The UMC zone experienced 585 extreme cold events related to attributable increases in the mortality rate. The average number of cold waves in the rural zones was 319. The primary risk factor was the percentage of population over age 64, and the primary protective factor was housing rehabilitation. As a whole, the period experienced more cold waves (1542) than heat waves (1130). Conclusion The UMC was more vulnerable than the rural areas. Furthermore, the results support the development of prevention policies, especially considering the fact that cold wave events were more frequent than heat waves.
Acute myocardial infarction (AMI) is a major public health problem. Cold winter weather increases the risk of AMI, but factors influencing susceptibility are poorly known. We conducted an individual-level case-crossover study of the associations between winter cold spells and the risk of AMI, with special focus on survival at 28 days and effect modification by age and sex. All 16,071 adult cases of AMI among the residents of the city of Kaunas in Lithuania in 2000-2015 were included in the study. Cold weather was statistically defined using the 5th percentile of frequency distribution of daily mean temperatures over the winter months. According to conditional logistic regression controlling for time-varying and time-invariant confounders, each additional cold spell day during the week preceding AMI increased the risk of AMI by 5% (95% CI 1-9%). For nonfatal and fatal cases, the risk increase per each additional cold spell day was 5% (95% CI 1-9%) and 6% (95% CI – 2-13%), respectively. The effect estimate was greater for men (OR 1.07, 95% CI 1.02-1.12) than for women (OR 1.02, 95% CI 0.97-1.08), but there was no evidence of effect modification by age. Evidence on factors increasing susceptibility is critical for targeted cold weather planning.
Human health can be negatively impacted by hot or cold weather, which often exacerbates respiratory or cardiovascular conditions and increases the risk of mortality. Urban populations are at particular increased risk of effects from heat due to the Urban Heat Island (UHI) effect (higher urban temperatures compared with rural ones). This has led to extensive investigation of the summertime UHI, its impacts on health, and also the consideration of interventions such as reflective ‘cool’ roofs to help reduce summertime overheating effects. However, interventions aimed at limiting summer heat are rarely evaluated for their effects in wintertime, and thus their overall annual net impact on temperature-related health effects are poorly understood. In this study we use a regional weather model to simulate the winter 2009/10 period for an urbanized region of the UK (Birmingham and the West Midlands), and use a health impact assessment to estimate the impact of reflective ‘cool’ roofs (an intervention usually aimed at reducing the UHI in summer) on cold-related mortality in winter. Cool roofs have been shown to be effective at reducing maximum temperatures during summertime. In contrast to the summer, we find that cool roofs have a minimal effect on ambient air temperatures in winter. Although the UHI in summertime can increase heat-related mortality, the wintertime UHI can have benefits to health, through avoided cold-related mortality. Our results highlight the potential annual net health benefits of implementing cool roofs to reduce temperature-related mortality in summer, without reducing the protective UHI effect in winter. Further, we suggest that benefits of cool roofs may increase in future, with a doubling of the number of heat-related deaths avoided by the 2080s (RCP8.5) compared to summer 2006, and with insignificant changes in the impact of cool-roofs on cold-related mortality. These results further support reflective ‘cool’ roof implementation strategies as effective interventions to protect health, both today and in future.
In light of climate change, health risks are expected to be exacerbated by more frequent high temperatures and reduced by less frequent cold extremes. To assess the impact of different climate change scenarios, it is necessary to describe the current effects of temperature on health. A time-stratified case-crossover design fitted with conditional quasi-Poisson regressions and distributed lag non-linear models was applied to estimate specific temperature-mortality associations in nine urban agglomerations in Belgium, and a random-effect meta-analysis was conducted to pool the estimates. Based on 307,859 all-cause natural deaths, the mortality risk associated to low temperature was 1.32 (95% CI: 1.21-1.44) and 1.21 (95% CI: 1.08-1.36) for high temperature relative to the minimum mortality temperature (23.1 °C). Both cold and heat were associated with an increased risk of cardiovascular and respiratory mortality. We observed differences in risk by age category, and women were more vulnerable to heat than men. People living in the most built-up municipalities were at higher risk for heat. Air pollutants did not have a confounding effect. Evidence from this study helps to identify specific populations at risk and is important for current and future public health interventions and prevention strategies.
Ambient temperature can affect the survival rate of humans. Studies have shown a relationship between ambient temperature and mortality rate in hot and cold environments. This effect of ambient temperature on mortality seems to be more pronounced in older people. The aim of this study is to examine the effects of thermal stress on cardiovascular mortality and the associated relative risk per degree Celsius in Greek individuals ≥70 years old. Mortality data 1999-2012 were matched with the midday temperature. The present study found a higher circulatory mortality when ambient temperature is below or above the temperature range 6 to 39 °C.
OBJECTIVES: To identify the associations of temperature with non-COVID-19 mortality and all-cause mortality in the pandemic 2020 in comparison with the non-COVID-19 period in Italy. METHODS: The data on 3,189,790 all-cause deaths (including 3,134,137 non-COVID-19 deaths) and meteorological conditions in 107 Italian provinces between February 1st and November 30th in each year of 2015-2020 were collected. We employed a time-stratified case-crossover study design combined with the distributed lag non-linear model to investigate the relationships of temperature with all-cause and non-COVID-19 mortality in the pandemic and non-pandemic periods. RESULTS: Cold temperature exposure contributed higher risks for both all-cause and non-COVID-19 mortality in the pandemic period in 2020 than in 2015-2019. However, no different change was found for the impacts of heat. The relative risk (RR) of non-COVID-19 deaths and all-cause mortality at extremely cold (2 °C) in comparison with the estimated minimum mortality temperature (19 °C) in 2020 were 1.63 (95% CI: 1.55-1.72) and 1.45 (95%CI: 1.31-1.61) respectively, which were higher than all-cause mortality risk in 2015-2019 with RR of 1.19 (95%CI: 1.17-1.21). CONCLUSION: Cold exposure indicated stronger impacts than high temperatures on all-cause and non-COVID-19 mortality in the pandemic year 2020 compared to its counterpart period in 2015-2019 in Italy.
BACKGROUND/AIM: Extreme temperatures have impact on the health and occupational injuries. The construction sector is particularly exposed. This study aims to investigate the association between extreme temperatures and occupation injuries in this sector, getting an insight in the main accidents-related parameters. METHODS: Occupational injuries in the construction sector, with characteristic of accidents, were retrieved from Italian compensation data during years 2014-2019. Air temperatures were derived from ERA5-land Copernicus dataset. A region based time-series analysis, in which an over-dispersed Poisson generalized linear regression model, accounting for potential non-linearity of the exposure- response curve and delayed effect, was applied, and followed by a meta-analysis of region-specific estimates to obtain a national estimate. The relative risk (RR) and attributable cases of work-related injuries for an increase in mean temperature above the 75th percentile (hot) and for a decrease below the 25th percentile (cold) were estimated, with effect modifications by different accidents-related parameters. RESULTS: The study identified 184,936 construction occupational injuries. There was an overall significant effect for high temperatures (relative risk (RR) 1.216 (95% CI: (1.095-1.350))) and a protective one for low temperatures (RR 0.901 (95% CI: 0.843-0.963)). For high temperatures we estimated 3,142 (95% CI: 1,772-4,482) attributable cases during the studied period. RRs from 1.11 to 1.30 were found during heat waves days. Unqualified workers, as well as masons and plumbers, were found to be at risk at high temperatures. Construction, quarry and industrial sites were the risky working environments, as well as specific physical activities like working with hand-held tools, operating with machine and handling of objects. Contact with sharp, pointed, rough, coarse ‘Material Agent’ were the more risky mode of injury in hot conditions. CONCLUSIONS: Prevention policies are needed to reduce the exposure to high temperatures of construction workers. Such policies will become a critical issue considering climate change.
BACKGROUND: Human beings and society are experiencing substantial consequences caused by non-optimum temperatures. However, limited studies have assessed the economic burden of premature deaths attributable to non-optimum temperatures. OBJECTIVES: To characterize the association between daily mean temperature and the economic burden of premature deaths. METHODS: A total of 3 228 098 deaths were identified from a national mortality dataset in Italy during 2015 and 2019. We used the value of statistical life to quantify the economic losses of premature death. A two-stage time-series analysis was performed to evaluate the economic losses of premature deaths associated with non-optimum temperatures. Attributable burden for non-optimum temperatures compared with minimum risk temperature were estimated. Potential effect modifiers were further explored. RESULTS: From 2015 to 2019, the economic loss of premature deaths due to non-optimum temperatures was $525.52 billion (95% CI: $461.84-$580.80 billion), with the attributable fraction of 5.74% (95% CI: 5.04%-6.34%). Attributable economic burden was largely due to moderate cold temperatures ($309.54 billion, 95% CI: $249.49-$357.34 billion). A higher economic burden was observed for people above the age of 65, accounting for 75.97% ($452.42, 95%CI: $406.97-$488.76 billion) of the total economic burden. In particular, higher fractions attributable to heat temperatures were observed for provinces with the lowest level of GDP per capita but the highest level of urbanization. DISCUSSION: This study shows a considerable economic burden of premature deaths attributed to non-optimum temperatures. These figures can help inform tailored prevention to tackle the large economic burden imposed by non-optimum temperatures.
Climate change and climate-sensitive disasters caused by climatic hazards have a significant and increasing direct and indirect impact on human health. Due to its vast area, complex geographical environment and various climatic conditions, Russia is one of the countries that suffers significantly from frequent climate hazards. This paper provides information about temperature extremes in Russia in the beginning of the 21st century, and their impact on human health. A literature search was conducted using the electronic databases Web of Science, Science Direct, Scopus, and e-Library, focusing on peer-reviewed Researchs published in English and in Russian from 2000 to 2021. The results are summarized in 16 studies, which are divided into location-based groups, including Moscow, Saint Petersburg and other large cities located in various climatic zones: in the Arctic, in Siberia and in the southern regions, in ultra-continental and monsoon climate. Heat waves in cities with a temperate continental climate lead to a significant increase in all-cause mortality than cold waves, compared with cities in other climatic zones. At the same time, in northern cities, in contrast to the southern regions and central Siberia, the influence of cold waves is more pronounced on mortality than heat waves. To adequately protect the population from the effects of temperature waves and to carry out preventive measures, it is necessary to know specific threshold values of air temperature in each city.
BACKGROUND: The increased risk of mortality during periods of high and low temperatures has been well established. However, most of the studies used daily counts of deaths or hospitalisations as health outcomes, although they are the ones at the top of the health impact pyramid reflecting only a limited proportion of patients with the most severe cases. OBJECTIVES: This study evaluates the relationship between short-term exposure to the daily mean temperature and medication prescribed for the respiratory system in five Spanish cities. METHODS: We fitted time series regression models to cause-specific medical prescriptions, including different respiratory subgroups and age groups. We included a distributed lag non-linear model with lags up to 14 days for daily mean temperature. City-specific associations were summarised as overall-cumulative exposure-response curves. RESULTS: We found a positive association between cause-specific medical prescriptions and daily mean temperature with a non-linear inverted J- or V-shaped relationship in most cities. Between 0.3% and 0.6% of all respiratory prescriptions were attributed to cold for Madrid, Zaragoza and Pamplona, while in cities with only cold effects the attributable fractions were estimated as 19.2% for Murcia and 13.5% for Santander. Heat effects in Madrid, Zaragoza and Pamplona showed higher fractions between 8.7% and 17.2%. The estimated costs are in general higher for heat effects, showing annual values ranging between €191,905 and €311,076 for heat per 100,000 persons. CONCLUSIONS: This study provides novel evidence of the effects of the thermal environment on the prescription of medication for respiratory disorders in Spain, showing that low and high temperatures lead to an increase in the number of such prescriptions. The consumption of medication can reflect exposure to the environment with a lesser degree of severity in terms of morbidity.
Extreme temperatures are a threat to public health, increasing mortality in the affected population. Moreover, there is substantial research showing how age and gender shape vulnerabilities to this environmental risk. However, there is only limited knowledge on how socioeconomic status (SES), operationalized using educational attainment, stratifies the effect of extreme temperatures on mortality. Here, we address this link using Poisson regression and administrative data from 2012 to 2018 for 50 Spanish Provinces on individuals aged above 65 matched with meteorological data provided by the E-OBS dataset. In line with previous studies, results show that hot and cold days increase mortality. Results on the interaction between SES and extreme temperatures show a positive and significant effect of exposure to heat and cold for individuals with medium and low SES level. Conversely, for high SES individuals we do not find evidence of a robust association with heat or cold. We further investigate how the local climate moderates these associations. A warmer climate increases risks with exposures to low temperatures and vice versa for hot temperatures in the pooled sample. Moreover, we observe that results are mostly driven by low SES individuals being particularly vulnerable to heat in colder climates and cold in warmer climates. In conclusion, results highlight how educational attainment stratifies the effect of extreme temperatures and the relevance of the local climate in shaping risks of low SES individuals aged above 65.
New gridded climate datasets (GCDs) on spatially resolved modeled weather data have recently been released to explore the impacts of climate change. GCDs have been suggested as potential alternatives to weather station data in epidemiological assessments on health impacts of temperature and climate change. These can be particularly useful for assessment in regions that have remained understudied due to limited or low quality weather station data. However to date, no study has critically evaluated the application of GCDs of variable spatial resolution in temperature-mortality assessments across regions of different orography, climate, and size. Here we explored the performance of population-weighted daily mean temperature data from the global ERA5 reanalysis dataset in the 10 regions in the United Kingdom and the 26 cantons in Switzerland, combined with two local high-resolution GCDs (HadUK-grid UKPOC-9 and MeteoSwiss-grid-product, respectively) and compared these to weather station data and unweighted homologous series. We applied quasi-Poisson time series regression with distributed lag nonlinear models to obtain the GCD- and region-specific temperature-mortality associations and calculated the corresponding cold- and heat-related excess mortality. Although the five exposure datasets yielded different average area-level temperature estimates, these deviations did not result in substantial variations in the temperature-mortality association or impacts. Moreover, local population-weighted GCDs showed better overall performance, suggesting that they could be excellent alternatives to help advance knowledge on climate change impacts in remote regions with large climate and population distribution variability, which has remained largely unexplored in present literature due to the lack of reliable exposure data.
BACKGROUND: To date, little is known about the temporal variation of the temperature-mortality association among different demographic and socio-economic groups. The aim of this work is to investigate trends in cold- and heat- attributable mortality risk and burden by sex, age, education, marital status, and number of household occupants in the city of Turin, Italy. METHODS: We collected daily time-series of temperature and mortality counts by demographic and socio-economic groups for the period 1982-2018 in Turin. We applied standard quasi-Poisson regression models to data subsets of 25-year moving subperiods, and we estimated the temperature-mortality associations with distributed lag non-linear models (DLNM). We provided cross-linkages between the evolution of minimum mortality temperatures, relative risks of mortality and temperature-attributable deaths under cold and hot conditions. RESULTS: Our findings highlighted an overall increase in risk trends under cold and heat conditions. All-cause mortality at the 1st percentile increased from 1.15 (95% CI: 1.04; 1.28) in 1982-2006 to 1.24 (95% CI: 1.11; 1.38) in 1994-2018, while at the 99th percentile the risk shifted from 1.51 (95% CI: 1.41; 1.61) to 1.59 (95% CI: 1.49; 1.71). In relation to social differences, women were characterized by greater values in respect to men, and similar estimates were observed among the elderly in respect to the youngest subgroup. Risk trends by educational subgroups were mixed, according to the reference temperature condition. Finally, individuals living in conditions of isolation were characterized by higher risks, with an increasing vulnerability throughout time. CONCLUSIONS: The overall increase in cold- and heat- related mortality risk suggests a maladaptation to ambient temperatures in Turin. Despite alert systems in place increase public awareness and improve the efficiency of existing health services at the local level, they do not necessarily prevent risks in a homogeneous way. Targeted public health responses to cold and heat in Turin are urgently needed to adapt to extreme temperatures due to climate change.
Using novel weekly mortality data for London spanning 1866-1965, we analyze the changing relationship between temperature and mortality as the city developed. Our main results show that warm weeks led to elevated mortality in the late nineteenth century, mainly due to infant deaths from digestive diseases. However, this pattern largely disappeared after WWI as infant digestive diseases became less prevalent. The resulting change in the temperature-mortality relationship meant that thousands of heat-related deaths-equal to 0.9-1.4 percent of all deaths- were averted. These findings show that improving the disease environment can dramatically alter the impact of high temperature on mortality.
Previous studies on the connection between climate and plague were mostly conducted without considering the influence of large-scale atmospheric circulations and long-term historical observations. The current study seeks to reveal the sophisticated role of climatic control on plague by investigating the combined effect of North Atlantic Oscillation (NAO) and temperature on plague outbreaks in Europe from 1347 to 1760 CE. Moving correlation analysis is applied to explore the non-linear relationship between NAO and plague transmission over time. Also, we apply the cross-correlation function to identify the role of temperature in mediating the NAO-plague connection and the lead-lag relationship in between. Our statistical results show that the pathway from climate change to plague incidence is distinctive in its spatial, temporal, and non-linear patterns. The multi-decadal temperature change exerted a 15-22 years lagged impact on the NAO-plague correlation in different European regions. The NAO-plague correlation in Atlantic-Central Europe primarily remained positive, while the correlation in Mediterranean Europe switched between positive and negative alternately. The modulating effect of temperature over the NAO-plague correlation increases exponentially with the magnitude of the temperature anomaly, but the effect is negligible between 0.3 and -0.3 degrees C anomaly. Our findings show that a lagged influence from the temperature extremes dominantly controls the correlation between NAO and plague incidence. A forecast from our study suggests that large-scale plague outbreaks are unlikely to happen in Europe if NAO remains at its current positive phase during the earth’s future warming. (C) 2020 Elsevier B.V. All rights reserved.
The cold season is usually accompanied by an increased incidence of respiratory infections and increased air pollution from combustion sources. As we are facing growing numbers of COVID-19 cases caused by the novel SARS-CoV-2 coronavirus, an understanding of the impact of air pollutants and meteorological variables on the incidence of respiratory infections is crucial. The incidence of influenza-like illness (ILI) can be used as a close proxy for the circulation of influenza viruses. Recently, SARS-CoV-2 has also been detected in patients with ILI. Using distributed lag nonlinear models, we analyzed the association between ILI, meteorological variables and particulate matter concentration in Bialystok, Poland, from 2013-2019. We found an exponential relationship between cumulative PM(2.5) pollution and the incidence of ILI, which remained significant after adjusting for air temperatures and a long-term trend. Pollution had the greatest effect during the same week, but the risk of ILI was increased for the four following weeks. The risk of ILI was also increased by low air temperatures, low absolute humidity, and high wind speed. Altogether, our results show that all measures implemented to decrease PM(2.5) concentrations would be beneficial to reduce the transmission of SARS-CoV-2 and other respiratory infections.
Background Previous studies investigating the relationship of influenza with acute myocardial infarction (AMI) have not distinguished between AMI types 1 and 2. Influenza and cold temperature can explain the increased incidence of AMI during winter but, because they are closely related in temperate regions, their relative contribution is unknown. Methods and Results The temporal relationship between incidence rates of AMI with demonstrated culprit plaque (type 1 AMI) from the regional primary angioplasty network and influenza, adjusted for ambient temperature, was studied in Madrid region (Spain) during 5 influenza seasons (from June 2013 to June 2018). A time-series analysis with quasi-Poisson regression models and distributed lag-nonlinear models was used. The incidence rate of type 1 AMI according to influenza vaccination status was also explored. A total of 8240 cases of confirmed type 1 AMI were recorded. The overall risk ratio (RR) of type 1 AMI during epidemic periods, adjusted for year, month, and temperature, was 1.23 (95% CI, 1.03-1.47). An increase of weekly influenza rate of 50 cases per 100 000 inhabitants resulted in an RR for type 1 AMI of 1.16 (95% CI, 1.09-1.23) during the same week, disappearing 1 week after. When adjusted for influenza, a decrease of 1ºC in the minimum temperature resulted in an increase of 2.5% type 1 AMI. Influenza vaccination was associated with a decreased risk of type 1 AMI in subjects aged 60 to 64 years (RR, 0.58; 95% CI, 0.47-0.71) and ≥65 years (RR, 0.53; 95% CI, 0.49-0.57). Conclusions Influenza and cold temperature were both independently associated with an increased risk of type 1 AMI, whereas vaccination was associated with a reduced risk among older patients.
Heat and cold temperatures associated with exposure to poor air quality lead to increased mortality. Using a generalized linear model with Poisson regression for overdispersion, this study quantifies the natural-caused mortality burden attributable to heat/cold temperatures and PM(10) and O(3) air pollutants in Rome and Milan, the two most populated Italian cities. We calculate local-specific mortality relative risks (RRs) for the period 2004-2015 considering the overall population and the most vulnerable age category (≥85 years). Combining a regional climate model with a chemistry-transport model under future climate and air pollution scenarios (RCP2.6 and RCP8.5), we then project mortality to 2050. Results show that for historical mortality the burden is much larger for cold than for warm temperatures. RR peaks during wintertime in Milan and summertime in Rome, highlighting the relevance of accounting for the effects of air pollution besides that of climate, in particular PM(10) for Milan and O(3) for Rome. Overall, Milan reports higher RRs while, in both cities, the elderly appear more susceptible to heat/cold and air pollution events than the average population. Two counterbalancing effects shape mortality in the future: an increase associated with higher and more frequent warmer daily temperatures – especially in the case of climate inaction – and a decrease due to declining cold-mortality burden. The outcomes highlight the urgent need to adopt more stringent and integrated climate and air quality policies to reduce the temperature and air pollution combined effects on health.
BACKGROUND: Although low temperature and air pollution exposures have been associated with the risk of anxiety, their combined effects remain unclear. OBJECTIVE: To investigate the independent and interactive effects of low temperature and air pollution exposures on anxiety. METHOD: Using a case-crossover study design, the authors collected data from 101,636 outpatient visits due to anxiety in three subtropical Chinese cities during the cold season (November to April in 2013 through 2018), and then built conditional logistic regression models based on individual exposure assessments [temperature, relative humidity, particulate matter (PM(2.5), PM(10)), sulfur dioxide (SO(2)), and nitrogen dioxide (NO(2))] and twelve cold spell definitions. Additive-scale interactions were assessed using the relative excess risk due to interaction (RERI). RESULTS: Both cold spell and air pollution were significantly associated with outpatients for anxiety. The effects of cold spell increased with its intensity, ranging from 8.98% (95% CI: 2.02%, 16.41%) to 15.24% (95% CI: 6.75%, 24.39%) in Huizhou. Additionally, each 10 μg/m(3) increase of PM(2.5), PM(10), NO(2) and SO(2) was associated with a 1.51% (95% CI: 0.61%, 2.43%), 1.58% (95% CI: 0.89%, 2.28%), 13.95% (9.98%, 18.05%) and 11.84% (95% CI: 8.25%, 15.55%) increase in outpatient visits for anxiety. Synergistic interactions (RERI >0) of cold spell with all four air pollutants on anxiety were observed, especially for more intense cold spells. For particulate matters, these interactions were found even under mild cold spell definitions [RERI: 0.11 (95% CI: 0.02, 0.21) for PM(2.5), and 0.24 (95% CI: 0.14, 0.33) for PM(10)]. Stratified analyses yielded a pronounced results in people aged 18-65 years. CONCLUSIONS: These findings indicate that both cold spell and air pollution are important drivers of the occurrence of anxiety, and simultaneous exposure to these two factors might have synergistic effects on anxiety. These findings highlight the importance of controlling air pollution and improving cold-warning systems.
BACKGROUND: The extreme thermal environment driven by climate change disrupts thermoregulation in pregnant women and may threaten the survival of the developing fetus. OBJECTIVES: To investigate the acute effect of maternal exposure to thermophysiological stress (measured with Universal Thermal Climate Index, UTCI) on the risk of stillbirth and modification of this effect by sociodemographic disparities. METHODS: We conducted a space-time-stratified case-crossover analysis of daily UTCI and 2835 singleton stillbirths between 1st January 2000 and 31st December 2015 across multiple small areas in Western Australia. Distributed lag non-linear models were combined with conditional quasi-Poisson regression to investigate the effects of the UTCI exposure from the preceding 6 days to the day of stillbirth. We also explored effect modification by fetal and maternal sociodemographic factors. RESULTS: The median UTCI was 13.9 °C (representing no thermal stress) while the 1st and 99th percentiles were 0.7 °C (slight cold stress) and 31.7 °C (moderate heat stress), respectively. Relative to median UTCI, we found positive associations between acute maternal cold and heat stresses and higher risks of stillbirth, increasing with the intensity and duration of the thermal stress episodes. The cumulative risk from the preceding 6 days to the day of stillbirth was stronger in the 99th percentile (RR = 1.19, 95% CI: 1.17, 1.21) than the 1st percentile (RR = 1.14, 95% CI: 1.12, 1.15), relative to the median UTCI. The risks were disproportionately higher in term and male stillborn fetuses, smoking, unmarried, ≤19 years old, non-Caucasian, and low socioeconomic status mothers. DISCUSSION: Acute maternal exposure to both cold and heat stresses may contribute to the risk of stillbirth and be exacerbated by sociodemographic disparities. The findings suggest public health attention, especially for the identified higher-risk groups. Future studies should consider the use of a human thermophysiological index, rather than surrogates such as ambient temperature.
Qinghai-Tibet Plateau (QTP) is one of the most sensitive regions to climate change in the world. As a result, people in the QTP are more likely to be sensitively affected by climate change than those in other regions, particularly in the poverty area. Using the Universal Thermal Climate Index (UTCI) derived from ERA5 and population data, changes in annual thermal comfort condition and population under such condition in the QTP are systematically analyzed. The results reveal that there is considerable regional heterogeneity in the distribution of UTCI and the number of comfortable days (CDs), mainly due to the complex geographic features. In most areas of the QTP, the increase in UTCI leads to an increased number of comfortable days. Spatial distribution and temporal change in the number of comfortable days are found to be principally related to altitude. In areas within altitudes of 3000-4500 m, the number of comfortable days increases by up to 6 d per decade, which is faster than that in higher elevation areas above 4500 m. Results also indicate that thermal comfortable condition has improved in areas of 2500-5000 m (medium to high altitude), particularly in spring and autumn. Further research indicates that population distribution also shows a regional clustering feature, with the majority of residents residing in cities and their vicinities, where a higher number of comfortable days were observed. Most areas with a greater number of comfortable days have experienced a more significant increase in population under thermal comfortable conditions. It implies that climate change more likely has a large influence on population in the QTP. These findings are expected to enhance tourism development and the assessment of the impact on the living environment. The findings can be helpful for optimizing of tourism development and better understanding how climate change affects population distribution.
Thermal comfort and environmental health in scenic open spaces, a communication bridge between tourists and their environment, are prerequisites for tourism activities. In this study, scenic open spaces in an urban area of Xi’an, China were selected. Thermal perception (thermal sensation, comfort and acceptability) of residents and tourists were investigated through meteorological measurement and questionnaire survey. Physiological equivalent temperature (PET) was used to determine thermal benchmarks of all visitors to the site. Variables that influence individual thermal perception assessment (physical, individual, society and psychology) were measured and compared. Finally, a series of strategies and suggestions were proposed based on meteorological characteristics and influencing factors of thermal perception from perspectives of designers and scenic spot managers. Results show that: 1) Neutral PET (NPET) of respondents were 17.3 °C (residents) and 15.5 °C (tourists). Neutral PET ranges (NPETR) were 8.9-25.8 °C (residents) and 7.2-23.8 °C (tourists). Preferred PET values were 20.1 °C (residents) and 19.7 °C (tourists). Thermal acceptability ranges (TAR) were 6.3-37.8 °C (residents) and 0.5-39.9 °C (tourists). 2) In winter, physical factors were primary influencers of residents’ thermal perception, followed by social factors, while tourists’ thermal perception was mainly influenced by physical factors. In spring, physical factors were still the primary influencers for residents, followed by individual factors. Physical factors were also dominant for tourists, followed by psychological. In summer, physical factors were the major influencing factors for residents and tourists’ thermal perceptions.
The study aims to investigate the thermal comfort requirements in residential buildings and to establish an adaptive thermal comfort model in the cold zone of China. A year-long field study was conducted in residential buildings in Xi’an, China. A total of 2069 valid questionnaires, along with indoor environmental parameters were obtained. The results indicated occupants’ thermal comfort requirements varied with seasons. The neutral temperatures were 17.9, 26.1 (highest), 25.2, and 17.4 degrees C (lowest), and preferred temperatures were 23.2, 25.6 (highest), 24.8, and 22.4 degrees C (lowest), respectively for spring, summer, autumn, and winter. The neutral temperature and preferred temperature in autumn are close to the neutral temperature in summer, while the neutral temperature and preferred temperature in spring are close to that in winter. Besides, the 80% and 90% acceptable temperature ranges, adaptive thermal comfort models, and thermal comfort zones for each season were established. Human’s adaptability is related to his/her thermal experience of the current season and the previous season. Therefore, compared with the traditional year-round adaptive thermal comfort model, seasonal models can better reflect seasonal variations of human adaptation. This study provides fundamental knowledge of the thermal comfort demand for people in this region.
BACKGROUND: Given that low income worsens health outcomes, income differences may affect health disparities in weather-related illnesses. The aim of this study was to investigate the association between income levels and prevalence of heat- and cold-related illnesses among Korean adults. METHODS: The current study comprised 535,186 participants with all variables on income and health behaviors. Patients with temperature-related illnesses were defined as individuals with outpatient medical code of heat- and cold-related illnesses. We categorized individual income into three levels: “low” for the fourth quartile (0-25%), “middle” for the second and the third quartiles (25-75%), and “high” for the first quartile (75-100%). To examine income-related health disparities, Cox proportional hazard regression was performed. Hazard ratios (HRs) and 95% CI (confidence interval) for heat- and cold-related illnesses were provided. The model adjusted for age, sex, smoking status, alcohol drinking, exercise, body mass index, hypertension, hyperglycemia, and local income per capita. RESULTS: A total of 5066 (0.95%) and 3302 (0.62%) cases identified patients with heat- and cold-related illnesses, respectively. Compared with high income patients, the adjusted HR for heat-related illnesses was significantly increased in the low income (adjusted HR = 1.103; 95% CI: 1.022-1.191). For cold-related illnesses, participants with low income were likely to have 1.217 times greater likelihood than those with high income (95% CI: 1.107-1.338), after adjusting for other covariates. In the stratified analysis of age (20-64 years and over 65 years) and sex, there was no difference in the likelihood of heat-related illnesses according to income levels. On the other hand, an HR for cold-related illnesses was higher in patients aged 20 to 64 years than in those aged over 65 years. Male with low income had also a higher HR for cold-related illnesses than female with low income. CONCLUSIONS: Our results showed that heat- or cold-related illnesses were more prevalent in Koreans with low income than those with high income. Strategies for low-income subgroups were needed to reduce greater damage due to the influence of extreme temperature events and to implement effective adaptation.
Changes of thermal environment can lead to unfavorable impacts such as a decrease of thermal stratification, increase of energy consumption, and increase of thermal health risk. Investigating changes in outdoor thermal environments can provide meaningful information for addressing economic and social issues and related challenges. In this study, thermal environment changes in South Korea were investigated using a nonstationary two-component Gaussian mixture model (NSGMM) for air temperature and two thermal comfort indices. For this, the perceived temperature (PT) and universal thermal climate index (UTCI) were employed as the thermal comfort index. Thermal comfort indices were computed using observed meteorological data at 26 weather stations for 37 years in South Korea. Meanwhile, trends of thermal comforts in the warm and cool seasons were simultaneously modeled by the NSGMM. The results indicate significant increasing trends in thermal comfort indices for South Korea. The increasing trends in thermal comfort indices both the warm and cool seasons were detected while the magnitudes of the trends are significantly different. This difference between the magnitude of trends led to an increase in mean and inter-annual variability of thermal comfort indices based on PT, while an increase of mean and decrease of inter-annual variability were observed based on the UTCI. Moreover, the annual proportion of the category referring to days in comfort based on the results of PT has decreased due to the different trends of thermal comfort indices in the warm and cool seasons. This decrease may lead to an increase of thermal health risk that is larger than what would be expected from the results considering the increasing trend of the annual mean temperature in South Korea. From this result, it can be inferred that the thermal health risk in South Korea may be more adverse than what we originally expected from the current temperature trend.
Determining the thresholds for risk assessment is critical for the successful implementation of thermal health warning systems. A risk assessment methodology with multiple thresholds must be developed to provide detailed warning information to the public and decision makers. This study developed a new methodology to identify multiple thresholds for different risk levels for heat or cold wave events by considering simultaneously impact on public health. A new objective function was designed to optimize segmented Poisson regression, which relates public health to temperature indicators. Thresholds were identified based on the values of the objective functions for all threshold candidates. A case study in identifying thresholds for cold and heat wave events in Seoul, South Korea, from 2014 to 2018, was conducted to evaluate the appropriateness of the proposed methodology. Daily minimum or maximum air temperature, mortality, and morbidity data were used for threshold identification and evaluation. The proposed methodology can successfully identify multiple thresholds to simultaneously represent different risk levels. These thresholds show comparable performance to those using the relative frequency approach.
Individual and meteorological factors are associated with cognitive function in older adults. However, how these two factors interact with each other to affect cognitive function in older adults is still unclear. We used mixed effects models to assess the association of individual and meteorological factors with cognitive function among older adults. Individual data in this study were from the database of China Family Panel Studies. A total of 3448 older adults from 25 provinces were included in our analysis. Cognitive functions were measured using a memory test and a logical sequence test. We used the meteorological data in the daily climate dataset of China’s surface international exchange stations, and two meteorological factors (i.e., average temperature and relative humidity) were assessed. The empty model showed significant differences in the cognitive scores of the older adults across different provinces. The results showed a main impact of residence (i.e., urban or rural) and a significant humidity-residence interaction on memory performance in older adults. Specifically, the negative association between humidity and memory performance was more pronounced in urban areas. This study suggested that meteorological factors may, in concert with individual factors, be associated with differences in memory function in older adults.
Background: The negative impacts of environmental factors on allergic respiratory diseases (ARD) in children have gotten a lot of attention recently. However, the influence of climatic conditions, especially extreme temperatures, on childhood ARD induced by house dust mites (HDM-ARD) is uncertain. Objective: We aimed to quantify the associations between outpatient visits for HDM-ARD and extreme temperatures in Shanghai, China. Methods: A distributed lag nonlinear model combined with Quasi-Poisson generalized linear model was used to analyze data. Results: Daily mean temperature was significantly associated with outpatient visits for childhood ARD and HDM-ARD. Exposure to extreme temperatures increased the cumulative relative risks of outpatient visits for ARD and HDM-ARD in children (RRlag0-28 for the 5th percentile of Tmean: 2.97, 95% confidence interval (CI): 1.25, 7.06; RRlag0-28 for the 95th percentile of Tmean: 2.85, 95% CI: 1.03, 7.86). Boys were vulnerable to extreme lower temperature, while girls were more sensitive to extreme higher temperature in both ARD and HDM-ARD. The effect seemed to be most pronounced among 6-11 years of age school children. Conclusion: Our study presents quantitative evidence that extreme temperatures prompted outpatient visits for children with ARD, especially HDM-ARD, in Shanghai, China. These findings might have significant consequences for developing appropriate preventive measures for vulnerable populations.
BACKGROUND: Ambient temperature change is a risk factor for urolithiasis that cannot be ignored. The association between temperature and urolithiasis varies from region to region. Our study aimed to analyze the impact of extremely high and low temperatures on the number of inpatients for urolithiasis and their lag effect in Ganzhou City, China. METHODS: We collected the daily number of inpatients with urolithiasis in Ganzhou from 2018 to 2019 and the meteorological data for the same period. The exposure-response relationship between the daily mean temperature and the number of inpatients with urolithiasis was studied by the distributed lag non-linear model (DLNM). The effect of extreme temperatures was also analyzed. A stratification analysis was performed for different gender and age groups. RESULTS: There were 38,184 hospitalizations for urolithiasis from 2018 to 2019 in Ganzhou. The exposure-response curve between the daily mean temperature and the number of inpatients with urolithiasis in Ganzhou was non-linear and had an observed lag effect. The warm effects (30.4°C) were presented at lag 2 and lag 5-lag 9 days, and the cold effects (2.9°C) were presented at lag 8 and lag 3-lag 4 days. The maximum cumulative warm effects were at lag 0-10 days (cumulative relative risk, CRR = 2.379, 95% CI: 1.771, 3.196), and the maximum cumulative cold effects were at lag 0-5 (CRR = 1.182, 95% CI: 1.054, 1.326). Men and people between the ages of 21 and 40 were more susceptible to the extreme temperatures that cause urolithiasis. CONCLUSION: Extreme temperature was correlated with a high risk of urolithiasis hospitalizations, and the warm effects had a longer duration than the cold effects. Preventing urolithiasis and protecting vulnerable people is critical in extreme temperature environments.
Epidemiological studies have proven that extreme temperatures have a significant threat to public health. This study aimed to investigate the association between extreme temperatures and circulatory mortality from January 1, 2014, to December 31, 2016, in Harbin, a city with a cold climate in Northeast China. We set a maximum lag of 27 days to evaluate the hysteresis effects of different temperatures on circulatory mortality using a distributed lag nonlinear model (DLNM). Results indicated that daily mean temperature and circulatory mortality presented approximately an L-shaped, and the cumulative relative risks (RRs) decreased continuously as the temperature increased in both low and high temperatures. Extremely low temperature showed a hysteresis and durability on circulatory mortality, with the largest RR of 1.023 (95%CI: 1.001-1.046) at lag 26, and RR of the cumulative cold effect of 0-27 days was 1.302 (95%CI: 1.160-1.462). The effect of extremely high temperatures presented more acute and intense, with the largest RR of 1.033 (95%CI: 1.004-1.063) at lag 0. RR of the cumulative hot effect of 0-3 days was 1.056 (1.008-1.106). In addition, females were more susceptible to extremely low temperatures, while males were more vulnerable to extremely high temperatures. This study demonstrated that extremely low temperatures have a stronger effect on circulatory mortality than extremely high temperatures in Harbin.
With the rapid increase in global warming, the impact of extreme temperatures on morbidity and mortality related to respiratory diseases has attracted considerable attention. In the current study, we quantified the relative risks (RRs) of mortality for respiratory diseases in three capital cities in Northeast China. We used a distributed lag nonlinear model (DLNM) based on a generalized additive model (GAM) to estimate the impact of extreme temperatures on respiratory mortality in Shenyang, Changchun, and Harbin from 2014 to 2016. The results revealed that the maximum cumulative RRs and 95% confidence intervals (CIs) were 1.52 (1.28-1.80), 1.42 (1.07-1.89), and 1.38 (1.21-1.58) in Shenyang, Changchun, and Harbin respectively when the median temperature was used as reference. The effect of extremely high temperature (99th percentile relative to 90th percentile) on respiratory mortality was found to be strongest in Shenyang (at the lowest latitude), while the effect of extreme low temperature (1st percentile relative to 10th percentile) on respiratory mortality was strongest in Harbin (at the highest latitude). In Shenyang and Changchun, the effects of high temperatures were much more intense and pronounced in females. Furthermore, the effect of high temperatures was more acute, whereas the effect of low temperatures was longer lasting.
Global climate change increased air temperature variability and enhanced the frequency and intensity of extreme weather events, such as heat waves and cold spells with adverse impacts on public health. In this study, we examined the relationships of the daily air temperature with mortality in Shanghai in 2003, a record hot year. We found V-shaped associations between causespecific mortality and daily air temperature. The temperature-mortality relationship well manifests in three temperature measures, but with varied temperature thresholds for different age groups and mortality categories. Two heat waves and one cold spell were identified in 2003 and brought out excess mortality. The first heat wave lasting for 19 days had a significant impact on total non-accidental, cardiovascular and respiratory deaths compared to the corresponding reference period. The second heat wave lasting for 14 days have resulted in excess mortality in three categories of mortality but without statistical significance. The cold spell lasting for 7 days only had a significant impact on total non-accidental and cardiovascular mortality. We also found the elderly are more sensitive to temperature variation. Our results suggest that air temperature is a significant factor influencing human mortality, particularly for the elderly.
Out-of-hospital cardiac arrest (OHCA) is a notable public health issue with negative outcomes, such as high mortality and aftereffects. Additionally, the adverse effects of extreme temperatures on health have become more important under climate change; however, few studies have investigated the relationship between temperature and OHCA. In this study, we examined the association between temperature and OHCA and its underlying risk factors. We conducted a two-stage time-series analysis using a Poisson regression model with a distributed lag non-linear model (DLNM) and meta-analysis, based on a nationwide dataset from South Korea (2008-2018). We found that 17.4% of excess OHCA was attributed to cold, while 0.9% was attributed to heat. Based on central estimates, excess OHCA attributed to cold were more prominent in the population with hypertension comorbidity (31.0%) than the populations with diabetes (24.3%) and heart disease (17.4%). Excess OHCA attributed to heat were larger in the populations with diabetes (2.7%) and heart disease comorbidity (2.7%) than the population with hypertension (1.2%) based on central estimates. Furthermore, the time-varying excess OHCA attributed to cold have decreased over time, and although those of heat did not show a certain pattern during the study period, there was a weak increasing tendency since 2011. In conclusion, we found that OHCAs were associated with temperature, and cold temperatures showed a greater impact than that of hot temperatures. The effects of cold and hot temperatures on OHCA were more evident in the populations with hypertension, diabetes, and heart diseases, compared to the general population. In addition, the impacts of heat on OHCA increased in recent years, while those of cold temperatures decreased. Our results provide scientific evidence for policymakers to mitigate the OHCA burden attributed to temperature.
Understanding extreme temperature variations is important for countries to manage risks associated with climate change. Yet, the characteristics of temperature extremes and possible climate change impacts have not been adequately investigated in Singapore. In this study, we attempted to do so by defining 14 extreme temperature indices (ETIs) for the period of 1982-2018 in Singapore, and investigating the trends of those ETIs using a pre-whitening Man-Kendall test coupled with the Sen’s slope estimator method. The linear and nonlinear relationships between ETIs and El Nino Southern Oscillation (ENSO) were also examined using correlation, composite and wavelet analysis. Our results indicate that trends of temperature extremes varied according to station locations, ETIs and time scales. In all stations, ETIs such as the monthly mean value of the diurnal range between maximum and minimum temperatures (DTR), cool nights (TN10p) and cool days (TX10p) presented decreasing trends, while the rest of them exhibited increasing trends. The composite values varied for different ETIs-meaning that while eight no-threshold ETIs reflected smaller values, other ETIs reflected relatively larger composite values, indicating that ENSO may have affected those ETIs more. The ETIs were mainly statistically and significantly coherent with ENSO at a 2-8 year cycle. We hope that our findings would be beneficial for climate action planning and temperature-related disaster prevention in Singapore.
BACKGROUND: Previous studies have found that exposed to low and high outdoor temperature was associated with cardiovascular diseases morbidity and mortality. The risk factors for cardiovascular disease include high blood lipid, high uric acid (UA) and high fasting plasma glucose (FPG). However, few studies have explored the effects of low and high temperature on these metabolic indicators. OBJECTIVE: To explore the effect of low and high temperature on metabolic indicators in adults from northwest of China. METHODS: Based on a prospective cohort study, a total of 30,759 individuals who participated in both baseline and first follow-up from 2011 to 2015 were selected in this study. The meteorological observation data and environmental monitoring data were collected in the same period. Associations between cold and hot temperature and blood lipid (total cholesterol (TC), triglycerides (TG), low density lipoprotein-cholesterol (LDL-C), and high density lipoprotein-cholesterol (HDL-C)), UA and FPG were conducted with mixed effect models after adjusting for confounding factors. RESULTS: A nonlinear relationship between outdoor temperature and metabolic indicators was found. For the cold effects, each 5 °C decrease of mean temperature was associated with an increase of 5.07% (95% CI: 3.52%, 6.63%) in TG and 2.85% (95% CI: 2.18%, 3.53%) in UA, While a decrease of 3.38% (95% CI: 2.67%, 4.09%) in HDL-C and 1.26% (95% CI: 0.48%, 2.04%) in LDL-C. For the heat effects, each 5 °C increase in mean temperature was associated with 1.82% (95% CI: 0.89%, 2.76%), 0.56% (95% CI: 0.11%, 1.00%), 5.82% (95% CI: 4.58%, 7.06%), 9.02% (95% CI: 7.17%, 10.87%), 0.20% (95% CI: 0.01%, 0.40%), and 1.22% (95% CI: 0.19%, 2.24%) decrease in TC, TG, HDL-C, LDL-C, UA and FPG. Age, smoking, drinking, high-oil diet and hyperlipidemia might modify the association between mean temperature and metabolic indicators. CONCLUSION: There was a significant effect of cold and hot temperature on metabolic indicators in a high altitude area of northwestern China. These results provide a basis for understanding the underlying mechanism of the influence of temperature on metabolic diseases.
BACKGROUND: The influences of air pollution exposure and temperature on respiratory diseases have become major global health concerns. This study investigated the relationship between ambient air pollutant concentrations and temperature in cold industrial cities that have the risk of hospitalization for respiratory diseases. METHODS: A time-series study was conducted in Changchun, China, from 2015 to 2019 to analyse the number of daily admissions for respiratory diseases, air pollutant concentrations, and meteorological factors. Time-series decomposition was applied to analyse the trend and characteristics of the number of admissions. Generalized additive models and distributed lag nonlinear models were constructed to explore the effects of air pollutant concentrations and temperature on the number of admissions. RESULTS: The number of daily admissions showed an increasing trend, and the seasonal fluctuation was obvious, with more daily admissions in winter and spring than in summer and autumn. There were positive and gradually decreasing lag effects of PM10, PM2.5, NO(2), and CO concentrations on the number of admissions, whereas O(3) showed a J-shaped trend. The results showed that within the 7-day lag period, 0.5°C was the temperature associated with the lowest relative risk of admission due to respiratory disease, and extremely low and high temperatures (<-18°C, >27°C, respectively) increased the risk of hospitalization for respiratory diseases by 8.3% and 12.1%, respectively. CONCLUSIONS: From 2015 to 2019, respiratory diseases in Changchun showed an increasing trend with obvious seasonality. The increased concentrations of SO(2), NO(2), CO, PM2.5, O(3) and PM10 lead to an increased risk of hospitalization for respiratory diseases, with a significant lag effect. Both extreme heat and cold could lead to increases in the risk of admission due to respiratory disease.
Extreme temperature could affect traffic crashes by influencing road safety, vehicle performance, and drivers’ behavior and abilities. Studies evaluating the impacts of extreme temperatures on the risk of traffic crashes have mainly overlooked the potential role of vehicle air conditioners. The aim of this study, therefore, was to evaluate the effect of exposure to extreme cold and hot temperatures on seeking medical attention due to motorcycle crashes. The study was conducted in Iran by using medical attendance for motorcycle crashes from March 2011 to June 2017. Data on daily minimum, mean and maximum temperature (°C), relative humidity (%), wind velocity (km/h), and precipitation (mm/day) were collected. We developed semi-parametric generalized additive models following a quasi-Poisson distribution with the distributed nonlinear lag model to estimate the immediate and lagged associations (reported as relative risk [RR], and 95% confidence interval [CI]). Between March 2011 and June 2017, 36,079 medical attendances due to motorcycle road traffic crashes were recorded (15.8 ± 5.92 victims per day). In this time period, the recorded temperature ranged from -11.2 to 45.4 °C (average: 25.5 ± 11.0 °C). We found an increased risk of medical attendance for motorcycle crashes (based on maximum daily temperature) at both extremely cold (1st percentile) and hot (99th percentile) temperatures and also hot (75th percentile) temperatures, mainly during lags 0 to 3 days (e.g., RR: 1.12 [95% CI: 1.05: 1.20]; RR: 1.08 [95% CI: 1.01: 1.16]; RR: 1.20 [95% CI: 1.09: 1.32] at lag0 for extremely cold, hot, and extremely hot conditions, respectively). The risk estimates for extremely hot temperatures were larger than hot and extremely cold temperatures. We estimated that 11.01% (95% CI: 7.77:14.06) of the medical attendance for motorcycle crashes is estimated to be attributable to non-optimal temperature (using mean temperature as exposure variable). Our findings have important public health messaging, given the considerable burden associated with road traffic injury, particularly in low- and middle-income countries.
BACKGROUND: Out-of-hospital-cardiac arrest (OHCA) is frequently linked to environmental exposures. Climate change and global warming phenomenon have been found related to cardiovascular morbidity, however there is no agreement on their impact on OHCA occurrence. In this nationwide analysis, we aimed to assess the incidence of the OHCA events attended by emergency medical services (EMS), in relation to meteorological conditions: temperature, humidity, heat index and solar radiation. METHODS: We analyzed all adult cases of OHCA in Israel attended by EMS during 2016-2017. In the case-crossover design, we compared ambient exposure within 72 h prior to the OHCA event with exposure prior to the four control times using conditional logistic regression in a lag-distributed non-linear model. RESULTS: There were 12,401 OHCA cases (68.3% were pronounced dead-on-scene). The patients were on average 75.5 ± 16.2 years old and 55.8% of them were males. Exposure to 90th and 10th percentile of temperature adjusted to humidity were positively associated with the OHCA with borderline significance (Odds Ratio (OR) =1.20, 95%CI 0.97; 1.49 and OR 1.16, 95%CI 0.95; 1.41, respectively). Relative humidity below the 10th percentile was a risk factor for OHCA, independent of temperature, with borderline significance (OR = 1.16, 95%CI 0.96; 1.38). Analysis stratified by seasons revealed an adverse effect of exposure to 90th percentile of temperature when estimated in summer (OR = 3.34, 95%CI 1.90; 3.5.86) and exposure to temperatures below 10th percentile in winter (OR = 1.75, 95%CI 1.23; 2.49). Low temperatures during a warm season and high temperatures during a cold season had a protective effect on OHCA. The heat index followed a similar pattern, where an adverse effect was demonstrated for extreme levels of exposure. CONCLUSIONS: Evolving climate conditions characterized by excessive heat and low humidity represent risk factors for OHCA. As these conditions are easily avoided, by air conditioning and behavioral restrictions, necessary prevention measures are warranted.
Epidemiological studies have reported the association between extreme temperatures and adverse reproductive effects. However, the susceptible period of exposure during pregnancy remains unclear. This study aimed to assess the impact of extreme temperature on the stillbirth rate. We performed a time-series analysis to explore the associations between temperature and stillbirth with a distributed lag nonlinear model. A total of 22,769 stillbirths in Taiwan between 2009 and 2018 were enrolled. The mean stillbirth rate was 11.3 ± 1.4 per 1000 births. The relative risk of stillbirth due to exposure to extreme heat temperature (> 29 °C) was 1.18 (95% CI 1.11, 1.25). Pregnant women in the third trimester were most susceptible to the effects of extreme cold and heat temperatures. At lag of 0-3 months, the cumulative relative risk (CRR) of stillbirth for exposure to extreme heat temperature (29.8 °C, 97.5th percentile of temperature) relative to the optimal temperature (21 °C) was 2.49 (95% CI: 1.24, 5.03), and the CRR of stillbirth for exposure to extreme low temperature (16.5 °C, 1st percentile) was 1.29 (95% CI: 0.93, 1.80). The stillbirth rate in Taiwan is on the rise. Our findings inform public health interventions to manage the health impacts of climate change.
BACKGROUND: This study aimed to explore the effects of heatwaves and cold spells on blood pressure, thrombus formation, and systemic inflammation at admission in patients with ischemic stroke. METHODS: Data of patients with ischemic stroke who were admitted to the Second Hospital of Tianjin Medical University between May 2014 and March 2019 were reviewed, along with meteorological data from the same time period. A total of 806 clinically confirmed patients with ischemic stroke (34-97 years old) were included in the final analysis. Heatwaves and cold spells were defined as ≥2 consecutive days with average temperature >95(th) percentile (May-August) and <5(th) percentile (November-March), respectively. Coagulation parameters, inflammation indices, blood pressure, and neurological impairment were evaluated within 24 hours of admission. General linear and logistic regression models were created to investigate the relationships of heatwaves and cold spells with the examination results of patients with ischemic stroke at admission. RESULTS: After adjustment for potential environmental confounders, heatwaves were positively associated with high systolic blood pressure (SBP) (β=8.693, P=0.019), diastolic blood pressure (DBP) (β=3.665, P=0.040), reduced thrombin time (TT) (β=-0.642, P=0.027), and activated partial thromboplastin time (APTT) (β=-1.572, P=0.027) in ischemic stroke patients at admission. Cold spells were positively associated with high SBP (β=5.277, P=0.028), DBP (β=4.672, P=0.012), fibrinogen (β=0.315, P=0.011), globulin (β=1.523, P=0.011), and reduced TT (β=-0.784, P<0.001) and APTT (β=-1.062, P=0.024). Cold spells were also associated with a higher risk of respiratory infection [odds ratio (OR) =2.677, P=0.001]. CONCLUSIONS: Exposure to heatwaves or cold spells was associated with blood pressure and coagulation at admission in patients with ischemic stroke. Cold spells also resulted in higher levels of inflammation. These findings suggest that changes in coagulation, blood pressure, and inflammation may be the potential biological mechanisms underlying the cerebrovascular effects of exposure to extreme temperatures.
Day-to-day change in ambient temperature is associated with acute myocardial infarction (AMI) attacks, but evidence is scarce about the effects of extreme temperatures on the risk of AMI within hours of exposure. This study investigated the hour-level associations between extreme temperatures and AMI occurrence. State-wide data on AMI patients and temperature during winter and summer of 2013-2015 were obtained for Queensland state of Australia. We employed a fixed time-stratified case-crossover analysis to quantify the risk of AMI associated with temperature within 24 h after exposure. Subgroups analyses by age, gender and disease history were also conducted. We observed a very acute effect of cold on men (occurred 9-10 h after exposure), women (19-22 h after exposure), and the elderly (4-20 h after exposure). Cold was associated with elevated AMI risk for men within 9 h (OR = 2.1, 95 % CI: 1.2-3.6), women within 19 h (OR = 2.5, 95 % CI: 1.0-6.0), and the elderly within 4 h (OR: 2.0, 95 % CI: 1.0-4.0). However, elevated risk of AMI associated with heat occurred 15 h later for men (OR: 3.9; 95 % CI: 1.1-13.9) and 23 h later for adults (OR: 4.1, 95 % CI: 1.1-15.4). People never suffered AMI and the elderly with diabetes or hyperlipidaemia were particularly vulnerable to cold. Those that were particularly vulnerable to heat were men never experienced AMI or having hypertension or having hyperlipidaemia as well as women ever suffered AMI. Effects of temperature on AMI risk at sub-daily timescales should be considered to prevent cardiac events.
BACKGROUND: A growing number of studies have investigated the effect of increasing temperatures on morbidity and health service use. However, there is a lack of studies investigating the temperature-attributable cost burden. OBJECTIVES: This study examines the relationship of daily mean temperature with hospital admissions, length of hospital stay (LoS), and costs; and estimates the baseline temperature-attributable hospital admissions, and costs and in relation to warmer climate scenarios in Adelaide, South Australia. METHOD: A daily time series analysis using distributed lag non-linear models (DLNM) was used to explore exposure-response relationships and to estimate the aggregated burden of hospital admissions for conditions associated with temperatures (i.e. renal diseases, mental health, diabetes, ischaemic heart diseases and heat-related illnesses) as well as the associated LoS and costs, for the baseline period (2010-2015) and different future climate scenarios in Adelaide, South Australia. RESULTS: During the six-year baseline period, the overall temperature-attributable hospital admissions, LoS, and associated costs were estimated to be 3915 cases (95% empirical confidence interval (eCI): 235, 7295), 99,766 days (95% eCI: 14,484, 168,457), and AU$159 million (95% eCI: 18.8, 269.0), respectively. A climate scenario consistent with RCP8.5 emissions, and including projected demographic change, is estimated to lead to increases in heat-attributable hospital admissions, LoS, and costs of 2.2% (95% eCI: 0.5, 3.9), 8.4% (95% eCI: 1.1, 14.3), and 7.7% (95% eCI: 0.3, 13.3), respectively by mid-century. CONCLUSIONS: There is already a substantial temperature-attributable impact on hospital admissions, LoS, and costs which are estimated to increase due to climate change and an increasing aged population. Unless effective climate and public health interventions are put into action, the costs of treating temperature-related admissions will be high.
Introduction: Cardiovascular disease is one of the leading causes of mortality worldwide. Acute myocardial infarction (AMI) is associated with weather change. The study aimed to investigate if weather change was among the risk factors of coronary artery disease to influence AMI occurrence in Taiwan and to generate a model to predict the probabilities of AMI in specific weather and clinical conditions. Method: This observational study utilized the National Health Insurance Research Database and daily weather reports from Taiwan Central Weather Bureau to evaluate the discharge records of patients diagnosed with AMI from various hospitals in Taiwan between January 1, 2008 and December 31, 2011. Generalized additive models (GAMs) were used to estimate the effective parameters on the trend of the AMI incidence rate with respect to the weather and health factors in the time-series data and to build a model for predicting AMI probabilities. Results: A total of 40,328 discharges were listed. The minimum temperature, maximum wind speed, and antiplatelet therapy were negatively related to the daily AMI incidence; however, a drop of 1° when the air temperature was below 15°C was associated with an increase of 1.6% of AMI incidence. By using the meaningful parameters including medical and weather factors, an estimated GAM was built. The model showed an adequate correlation in both internal and external validation. Conclusion: An increase in AMI occurrence in colder weather has been evidenced in the study, but the influence of wind speed remains uncertain. Our analysis demonstrated that the novel GAM model can predict daily onset rates of AMI in specific weather conditions.
Little evidence about the effects of cold spells on serum lipid levels is available. The aim of this study was to explore the association between cold spells and serum lipid levels among the elders in Jinan, China. Data of old adults from health check-up program in Shandong Provincial Qianfoshan Hospital was collected for this study. Linear mixed models combined with distributed lag nonlinear models were used to examine the relationship between cold spells and serum lipid levels, considering the confounding effects of age, sex, blood pressure, body mass index, and other meteorological factors. Subgroup analysis by gender and analysis based on different definitions of cold spells were also conducted. Increased TG levels in lag 0-lag 2 days and decreased TG levels in lag 5-lag 8 days after cold spells were observed among the elders. The largest increase was 0.363 mmol/L (95% CI: 0.184 ~ 0.543) in lag 0 day, while the largest decreased TG levels was 0.083 mmol/L (95% CI: 0.147 ~ 0.019) in lag 6 day. Similar results were obtained in the analysis of different sex and based on different definitions of cold spells. However, no significant association was found between cold spells with TC, LDL-C, and HDL-C. This study indicates that cold spells were significantly associated with serum TG levels in the elders. Effective preventive measures should be implemented around the cold spells to reduce the volatility of serum lipid levels and the occurrence of subsequent cardiovascular diseases.
Background The association between ambient temperature and cardiovascular diseases has been well established, but evidence of temporal changes in the risk of acute aortic dissection (AAD) onset is lacking. Methods and Results We conducted an 8-year time-series study based on data from 2120 patients diagnosed with AAD at Tongji Hospital (Wuhan, China). Daily meteorological parameters were measured in the study area. Spearman’s rank correlation analysis was applied to measure the associations between daily meteorological data and air pollution indicators. A distributed lag nonlinear model following quasi-Poisson regression was used to express the nonlinear exposure-response relationships and lag effects of daily mean temperature and temperature variability on the occurrence of AAD. Considering a 25-day lag effect, lower or higher temperatures with reference to 25°C did not alter the onset risk of AAD. The lag effect of daily mean temperature on the incidence of AAD is statistically significant within 2 days, and the impact of daily mean temperature on the risk is most influential on the day. The exposure-response curve between daily mean temperature and onset risks of AAD at lag 0 showed that the extremely cold temperature (2.5th percentile, 0.5°C) significantly increased the AAD risk for the total (relative risk, 1.733; 95% CI, 1.130-2.658) and type A dissection (relative risk, 3.951; 95% CI, 1.657-9.418). Temperature variability within 1 week did not affect the onset risks of AAD for the total. Conclusions We confirmed that extremely cold temperatures significantly increased the AAD risk, which could contribute to early prevention and timely diagnosis of the disease.
Playgrounds in urban parks are important for children’s physical and mental health, but global warming has led to a worsening outdoor environment and children’s outdoor activities have been affected. Improving the outdoor thermal comfort (OTC) of playgrounds can encourage children to engage in more and safer outdoor activities. However, there are a limited number of studies focusing on preschoolers’ outdoor thermal comfort (OTC) and most of them have substituted children’s thermal comfort with caregivers’ evaluations. To investigate the differences between children’s and caregivers’ evaluations of thermal sensation, thermal benchmarks and thermal adaptive behavior for children, we conducted meteorological measurements on representative playgrounds in three parks in Wuhan, China, and administered thermal perception questionnaires to preschool children and their caregivers. In addition, the Physiological Equivalent Temperature (PET) was used to establish evaluation criteria for children’s OTC and to make recommendations for the improvement of the playground environment. We draw five conclusions by analyzing 719 valid questionnaires: (1) Children were less sensitive to changes in meteorological factors than caregivers and had better tolerance of cold environments. (2) The NPET for preschoolers was evaluated by children and by caregivers, respectively, as 22.9 degrees C and 22.3 degrees C in summer and 10.6 degrees C and 11.2 degrees C in winter. (3) Playgrounds in Wuhan’s parks are uncomfortable for a long time in summer and a short time in winter. (4) Both children and caregivers want to improve summer comfort by lowering the temperature and winter comfort by increasing solar radiation. At the same time, children and caregivers show different preferences in adaptive behavior choices. (5) Adding deciduous trees and water play facilities can improve the site thermal environment. Furthermore, the OTC of humans can be improved by adding more service facilities on playgrounds.
Due to limits to standard methods for surveying outdoor thermal comfort (OTC), it is difficult to compare thermal benchmarks and thermal index calibrations among studies and climatic regions. Using uniform standard meteorological measurements and questionnaire surveys, our study conducted an OTC study in urban parks in Beijing, Xi’an and Hami; representative of cities in China’s cold regions. The Universal Thermal Climate Index (UTCI) was used as the thermal comfort index, and differences in residents’ thermal perceptions and outdoor thermal benchmarks among these cities were compared. Results showed that: 1) air temperature (T(a)) and globe temperature (T(g)) were two primary factors affecting residents’ thermal sensations in the three cities during winter. Residents’ thermal sensation in Beijing and Hami was negatively correlated with wind speed (V(a)). Residents in Xi’an and Hami preferred a higher relative humidity (RH). Residents in Beijing and Hami preferred a lower V(a) to improve OTC related to local climatic characteristics. 2) Xi’an residents had the highest neutral UTCI (NUTCI) (17.3 °C), followed by Beijing (17.0 °C) and Hami (6.4 °C). Xi’an residents had slightly wider neutral UTCI range (NUTCIR) (7.9-26.7 °C) compared to Beijing (8.7-25.4 °C), while Hami residents had the narrowest NUTCIR (1.5-11.3 °C). The “no thermal stress” range in the three cities was 6.1-26.0 °C in Beijing, 6.7-25.5 °C in Xi’an, and -2.2-12.2 °C in Hami. 3) Calibrated thermal indices, based on the ASHRAE 7-point scale, were gained to judge the thermal qualities of an environment for all three cities.
BACKGROUND: The existing evidence suggests that pre-existing diabetes may modify the association between heat and hospitalizations for acute myocardial infarction (AMI). METHODS: This study included patients who were hospitalized for AMI from 1 January 2005 to 31 December 2013 in Brisbane, Australia, and also included those who died within 2 months after discharge. A time-stratified case-crossover design with conditional logistic regression was used to quantify the associations of heat and cold with hospitalizations and post-discharge deaths due to AMI in patients with and without pre-existing diabetes. Stratified analyses were conducted to explore whether age, sex and suburb-level green space and suburb-level socio-economic status modified the temperature-AMI relationship. Heat and cold were defined as the temperature above/below which the odds of hospitalizations/deaths due to AMI started to increase significantly. RESULTS: There were 14 991 hospitalizations for AMI and 1811 died from AMI within 2 months after discharge during the study period. Significant association between heat and hospitalizations for AMI was observed only in those with pre-existing diabetes (odds ratio: 1.19, 95% confidence interval: 1.00-1.41) [heat (26.3°C) vs minimum morbidity temperature (22.2°C)]. Cold was associated with increased odds of hospitalizations for AMI in both diabetes and non-diabetes groups. Significant association between cold and post-discharge deaths from AMI was observed in both diabetes and non-diabetes groups. CONCLUSIONS: Individuals with diabetes are more susceptible to hospitalizations due to AMI caused by heat and cold.
Climate may significantly affect human society. Few studies have focused on the temperature impact on residents’ health, especially mental health status. This paper uses 98 423 observations in China to study the relationship between temperature and health, based on the China Family Panel Studies survey during 2010-16. We analyze the health effects of extreme hot and cold weather and compare the effects under different social demographic factors including gender, age, and income. We find that temperature and health status exhibit a nonlinear relationship. Women and low-income households are more likely to be impacted by extreme cold, whereas men, the elderly, and high-income households are more sensitive to extreme heat. Our results highlight the potential effects of extreme temperatures on physical and mental health and provide implications for future policy decisions to protect human health under a changing climate.
OBJECTIVE: We aimed to examine the temporal trends of the association between extreme temperature and schizophrenia (SCZ) hospitalisations in Hefei, China. METHODS: We collected time-series data on SCZ hospitalisations for 10 years (2005-2014), with a total of 36 607 cases registered. We used quasi-Poisson regression and distributed lag non-linear model (DLNM) to assess the association between extreme temperature (cold and heat) and SCZ hospitalisations. A time-varying DLNM was then used to explore the temporal trends of the association between extreme temperature and SCZ hospitalisations in different periods. Subgroup analyses were conducted by age (0-39 and 40+ years) and gender, respectively. RESULTS: We found that extreme cold and heat significantly increased the risk of SCZ hospitalisations (cold: 1st percentile of temperature 1.19 (95% CI 1.04 to 1.37) and 2.5th percentile of temperature 1.16 (95% CI 1.03 to 1.31); heat: 97.5th percentile of temperature 1.37 (95% CI 1.13 to 1.66) and 99th percentile of temperature 1.38 (95% CI 1.13 to 1.69)). We found a slightly decreasing trend in heat-related SCZ hospitalisations and a sharp increasing trend in cold effects from 2005 to 2014. However, the risk of heat-related hospitalisation has been rising since 2008. Stratified analyses showed that age and gender had different modification effects on temporal trends. CONCLUSIONS: The findings highlight that as temperatures rise the body’s adaptability to high temperatures may be accompanied by more threats from extreme cold. The burden of cold-related SCZ hospitalisations may increase in the future.
To examine the associations between ambient temperature and hospitalizations for acute kidney injury (AKI) in Queensland, Australia, 1995-2016. Data were collected on a total of 34 379 hospitalizations for AKI from Queensland between 1 January 1995 and 31 December 2016. Meteorological data were downloaded from the Queensland Government’s Department of Environment and Science. We assessed the temperature-AKI relationship using a time-stratified case-crossover design fitted with conditional quasi-Poisson regression model and time-varying distributed lag non-linear model. Stratified analyses were performed by age, sex, climate zone and socioeconomic group. Both cold and hot temperatures were associated with hospitalizations for AKI. There were stronger temperature-AKI associations among women than men. Cold effects were only positive in the > 70 years age group. Hot effects were stronger in the <= 59 years age group than in the >60 years age group. In different climate zone areas, cold effects decreased with increasing local mean temperatures, while hot effects increased. In different socio-economic status groups, hot effects were stronger in the poor areas than the affluent areas. From 1995 to 2016, the magnitude of associations between cold temperature and hospitalizations for AKI decreased, while the hot effect increased. The associations between hot temperature and hospitalizations for AKI become stronger, while the magnitude of cold effect decreased from 1995 to 2016. This trend may accelerate over the coming decades, which warrants further research. More attention is needed toward susceptible population including women, people > 70 years, and the people living in hot climate zones and in low socioeconomic status areas.
This study aimed to estimate respiratory disease hospitalization costs attributable to ambient temperatures and to estimate the future hospitalization costs in Australia. The associations between daily hospitalization costs for respiratory diseases and temperatures in Sydney and Perth over the study period of 2010-2016 were analyzed using distributed non-linear lag models. Future hospitalization costs were estimated based on three predicted climate change scenarios-RCP2.6, RCP4.5 and RCP8.5. The estimated respiratory disease hospitalization costs attributable to ambient temperatures increased from 493.2 million Australian dollars (AUD) in the 2010s to more than AUD 700 million in 2050s in Sydney and from AUD 98.0 million to about AUD 150 million in Perth. The current cold attributable fraction in Sydney (23.7%) and Perth (11.2%) is estimated to decline by the middle of this century to (18.1-20.1%) and (5.1-6.6%), respectively, while the heat-attributable fraction for respiratory disease is expected to gradually increase from 2.6% up to 5.5% in Perth. Limitations of this study should be noted, such as lacking information on individual-level exposures, local air pollution levels, and other behavioral risks, which is common in such ecological studies. Nonetheless, this study found both cold and hot temperatures increased the overall hospitalization costs for respiratory diseases, although the attributable fractions varied. The largest contributor was cold temperatures. While respiratory disease hospitalization costs will increase in the future, climate change may result in a decrease in the cold attributable fraction and an increase in the heat attributable fraction, depending on the location.
BACKGROUND: Extreme temperatures are associated with the risk of preterm birth (PTB), but evidence on the effects of different clinical subtypes and across different regions is limited. We aimed to evaluate the effects of maternal exposure to extreme temperature on PTB and its clinical subtypes in China, and to identify effect modification of regional factors in dimensions of population, economy, medical resources and environmental factors. METHODS: This was a prospective population-based cohort of 210,798 singleton live births from 16 counties in eight provinces across China during 2014-2018. We used an extended Cox regression with time-varying variables to evaluate the effects of extreme heat and cold on PTB and its subtypes in the entire pregnancy, each trimester, the last gestational month and week. Meta-analysis and meta-regression were conducted to estimate the pooled effects of each city and effect modification by regional characteristics. FINDINGS: Exposure to heat and cold during the entire pregnancy significantly increased the risk of PTB. The effects varied with subtypes, for medically indicated and spontaneous PTB, hazard ratios were 1·84 (95% CI: 1·29, 2·61) and 1·50 (95% CI: 1·11, 2·02) for heat, 2·18 (95% CI: 1·83, 2·60) and 2·15 (95% CI: 1·92, 2·41) for cold. The associations were stronger for PTB less than 35 weeks than those during weeks 35-36. The effects varied across locations, and GDP per capita (β=-0·16) and hospital beds per 1000 persons (β=-0·25) were protective factors for the effects. INTERPRETATION: Extreme temperature can increase the risk of medically indicated and spontaneous PTB, and higher regional socio-economic status may moderate such effects. In the context of climate change, such findings may have important implications for protecting the health of vulnerable groups, especially newborns. FUNDING: National Key R&D Program of China (2018YFA0606200), National Natural Science Foundation of China (42175183), Strategic Priority Research Program of the Chinese Academy of Sciences (XDA20030302), National Natural Science Foundation of China (42071377).
Extreme temperatures were considered natural hazards because they could increase morbidity and mortality. Understanding the extreme temperature changes at different warming levels is crucial to climate change mitigation and adoption for human health. This study projected climate change effects on the intensity, occurrence, and duration of extreme temperatures in Taiwan with 2 and 4 degrees C global warming scenarios using the Weather Research and Forecasting model. The future climate simulations were conducted with the pseudo-global warming approach, and the future climate changes were obtained from the ensemble mean of simulations in the Coupled Model Intercomparison Project 5. The simulated daily mean temperature increased by 1.40 and 3.09 degrees C under 2 and 4 degrees C global warmings. In a warming world, the daily maximum temperature was projected to increase by 1.35-3.00 degrees C, whereas the daily minimum temperature was even higher, leading to weaker diurnal temperature variation in most regions. The simulation results show that intensified heatwaves with frequent and prolonged durations become par for the course, whereas extremely cold days disappear gradually. The occurrence of heatwaves in the future is projected to be five times that in the current climate. Comparing the global warming impacts over different land-use types, the heatwave occurrence over urban areas rose more quickly than over other land-use types; forests are less vulnerable to global warming. On the contrary, the changes in extremely cold days over urban areas were weaker than over other land-use types. Overall, the effects of global warming on temperature revealed that extreme events were more severe with increased temperature than with the mean state of air temperature. Nonlinear behaviours indicated that global warming should be limited to 2 degrees C, and the additional 2 degrees C warming (from 2 to 4 degrees C) should be addressed carefully.
Although numerous studies have investigated premature deaths attributable to temperature, effects of temperature on years of life lost (YLL) remain unclear. We estimated the relationship between temperatures and YLL, and quantified the YLL per death caused by temperature in China. We collected daily meteorological and mortality data, and calculated the daily YLL values for 364 locations (2013-2017 in Yunnan, Guangdong, Hunan, Zhejiang, and Jilin provinces, and 2006-2011 in other locations) in China. A time-series design with a distributed lag nonlinear model was first employed to estimate the location-specific associations between temperature and YLL rates (YLL/100,000 population), and a multivariate meta-analysis model was used to pool location-specific associations. Then, YLL per death caused by temperatures was calculated. The temperature and YLL rates consistently showed U-shaped associations. A mean of 1.02 (95% confidence interval: 0.67, 1.37) YLL per death was attributable to temperature. Cold temperature caused 0.98 YLL per death with most from moderate cold (0.84). The mean YLL per death was higher in those with cardiovascular diseases (1.14), males (1.15), younger age categories (1.31 in people aged 65-74 years), and in central China (1.34) than in those with respiratory diseases (0.47), females (0.87), older people (0.85 in people ≥75 years old), and northern China (0.64) or southern China (1.19). The mortality burden was modified by annual temperature and temperature variability, relative humidity, latitude, longitude, altitude, education attainment, and central heating use. Temperatures caused substantial YLL per death in China, which was modified by demographic and regional characteristics.
People in urban agglomerations (UAs) are increasingly exposed to elevated extreme temperature events under global warming and local human activities such as urbanization. While the urbanization effects on local temperature changes have been well studied, possibly different effects on human perceived temperature (HPT), which measures the compound influences of multiple indicators (e.g., temperature, humidity, and wind), remain much less understood. Here, we examine the long-term changes in mean and extreme HPT in 20 major UAs across the mainland of China since the 1970s, and evaluate the effect of urbanization based on a dynamic classification of urban and rural stations using time-varying land use/land cover maps. The results show that mean HPT and actual near-surface air temperature (T) in both summer and winter seasons display significant trends in most portions of China, while the frequency of extreme HPT and T events in summer (winter) exhibits increasing (decreasing) tendency. These trends are particularly stronger in more populated and urbanized UAs. It is estimated that urbanization averagely accounts for around 1/6 of the total increasing trend in mean HPT and T in the urban core areas of 20 UAs. In both seasons, the effects of urbanization on mean HPT are more profound than T. Moreover, urbanization significantly increases the occurrence frequency of summertime hot extremes and decreases the occurrence of wintertime cold events. Regionally, northern UAs in general exhibit more remarkable trends than the south. The urbanization process exerts more prominent effects in HPT than T in nearly three-quarters of all UAs, except several regions with a complex topography and lower urbanization level. These findings reported here can provide suggestions and support for urban planning of decision-maker and human perceived thermal comfort choices of humans living in UAs.
BACKGROUND: Non-optimal temperatures are associated with mortality risk, yet the heterogeneity of temperature-attributable mortality burden across subnational regions in a country was rarely investigated. We estimated the mortality burden related to non-optimal temperatures across all provinces in China in 2019. METHODS: The global daily temperature data were obtained from the ERA5 reanalysis dataset. The daily mortality data and exposure-response curves between daily temperature and mortality for 176 individual causes of death were obtained from the Global Burden of Disease Study 2019 (GBD 2019). We estimated the population attributable fraction (PAF) based on the exposure-response curves, daily gridded temperature, and population. We calculated the cause- and province-specific mortality burden based on PAF and disease burden data from the GBD 2019. FINDINGS: We estimated that 593·9 (95% UI:498·8, 704·6) thousand deaths were attributable to non-optimal temperatures in China in 2019 (PAF=5·58% [4·93%, 6·28%]), with 580·8 (485·7, 690·1) thousand cold-related deaths and 13·9 (7·7, 23·2) thousand heat-related deaths. The majority of temperature-related deaths were from cardiovascular diseases (399·7 [322·8, 490·4] thousand) and chronic respiratory diseases (177·4 [141·4, 222·3] thousand). The mortality burdens were observed significantly spatial heterogeneity for both high and low temperatures. For instance, the age-standardized death rates (per 100 000) attributable to low temperature were higher in Western China, with the highest in Tibet (113·7 [82·0, 155·5]), while for high temperature, they were greater in Xinjiang (1·8 [0·7, 3·3]) and Central-Southern China such as Hainan (2·5 [0·9, 5·4]). We also observed considerable geographical variation in the temperature-related mortality burden by causes of death at provincial level. INTERPRETATION: A substantial mortality burden was attributable to non-optimal temperatures across China, and cold effects dominated the total mortality burden in all provinces. Both cold- and heat-related mortality burden showed significantly spatial variations across China. FUNDING: National Key Research and Development Program.
Little is known about the association between air temperature and causes-specific respiratory diseases (RD), especially in northwest China. A time-stratified case crossover design with a distributed lag nonlinear model (DLNM) was conducted to assess the nonlinear and delayed ef-fects of temperature on total and cause-specific outpatient visits, with analyses stratified by gender and age. The cumulative effects of temperature were irregular M-shaped curves for total and upper respiratory tract infection (URTI), with inverted U-shaped curve for pneumonia, bronchitis and chronic obstructive pulmonary disease (COPD). Positive cold and heat effects were observed for URTI, pneumonia, bronchitis and COPD, bronchitis was most vulnerable to cold but pneumonia was more affected to heat. Heat effects were immediate whereas cold effects were delayed and lasted longer. The magnitude of temperature effects varies greatly by age, gender, and disease. Notably, the cold effect was greater for children aged 0-14 than that of other age groups. This study suggested that both cold and hot temperatures exposure could increase all-cause and cause-specific respiratory outpatient visits in Lanzhou, China. The harmful effect and duration of cold were greater than that of heat, and children aged 0-14 were more sensitive to cold. Protection against extreme temperatures should be strengthened.
BACKGROUND: Evidence is scant on the relative and attributable contributions of ambient temperature on stroke subtypes mortality. Few studies have examined modification effects of multiple greenness indicators on such contributions, especially in China. We quantified the associations between ambient temperature and overall, ischemic, and hemorrhagic stroke mortality; further examined whether the associations were modified by greenness. METHODS: We conducted a multicenter time-series analysis from January 1, 2013 to December 31, 2019. we adopted a distributed lag non-linear model to evaluate county-specific temperature-stroke mortality associations. We then applied a random-effects meta-analysis to pool county-specific effects. Attributable mortality was calculated for cold and heat, defined as temperatures below and above the minimum mortality temperature (MMT). Finally, We conducted a multivariate meta-regression to determine associations between greenness and stroke mortality risks for cold and heat, using normalized difference vegetation index (NDVI), soil adjusted vegetation index (SAVI), and enhanced vegetation index (EVI) as quantitative indicators of greenness exposure. RESULTS: In the study period, 138,749 deaths from total stroke were reported: 86,873 ischemic and 51,876 hemorrhagic stroke. We observed significant W-shaped relationships between temperature and stroke mortality, with substantial differences among counties and regions. With MMT as the temperature threshold, 17.16 % (95 % empirical CI, 13.38 %-19.75 %) of overall, 20.05 % (95 % eCI, 16.46 %-22.70 %) of ischemic, and 12.55 % (95 % eCI, 5.59 %-16.24 %) of hemorrhagic stroke mortality were attributable to non-optimum temperature (combining cold and heat), more mortality was caused by cold (14.94 %; 95 % eCI, 11.57 %-17.34 %) than by heat (2.22 %; 95 % eCI, 1.54 %-2.72 %). Higher levels of NDVI, SAVI and EVI were related to mitigated effects of non-optimum temperatures-especially heat. CONCLUSIONS: Exposure to non-optimum temperatures aggravated stroke mortality risks; increasing greenness could alleviate that risks. This evidence has important implications for local communities in developing adaptive strategies to minimize the health consequences of adverse temperatures.
Limited evidence is available on apparent temperature (AT) and hospital admissions for acute cardiac events. We examined the associations of AT with admissions for acute cardiac events and acute coronary syndrome (ACS), and explored the effect difference between ST-elevation myocardial infarction (STEMI) and non-ST-elevation myocardial infarction ACS (NSTE-ACS). Poisson regression with distributed lag non-linear model was applied to examine the temperature-lag-admission associations. Stratified analyses were performed by gender and age-groups for acute cardiac events. A total of 11,657 acute cardiac events admissions were collected from hospital-based chest pain centers in Beijing, during 2017-2019. The single day effect of low AT (-11 degrees C, 2.5th percentile) appeared on the 2nd day and persisted until the 11th day, with estimated relative risk (RR) ranging from 1.44 (95% CI: 1.159, 1.790) to 1.084 (95% CI: 1.022, 1.150) for acute cardiac events and from 1.034 (95% CI: 1.010, 1.059) to 1.006 (95% CI: 1.000, 1.011) for ACS. The single day effect of high AT (34 degrees C, 97.5th percentile) was only observed on the current day. The cold effect on acute cardiac events was more pronounced among female and older patients. The cumulative effect of high AT on STEMI admissions and low AT on NSTE-ACS reached a peak RR peak of 2.545 (95% CI: 1.016, 6.375) and 3.71 (95% CI: 1.315, 10.469) on lag 0-6 days, respectively. Both high and low ATs were associated with increased risk of acute cardiac events and ACS admissions. STEMI admissions may be more sensitive to high AT while NSTE-ACS to low AT.
BACKGROUND: Most studies have focused on the relationship between ambient temperature and stroke mortality, but studies on the relationship between ambient temperature and stroke occurrence are still limited and inconsistent. OBJECTIVE: This study aimed to analyze the effect of ambient temperature and other environmental factors on emergency stroke visits in Beijing. METHODS: Our study utilized stroke visit data from the Beijing Red Cross Emergency Medical Center during 2017-2018, and applied a generalized additive model (GAM) as well as a distributed lag non-linear model (DLNM), respectively, regarding the direct, lagged, and cumulative effects of ambient temperature alone and with correction for other environmental factors on stroke occurrence. RESULTS: With a total of 26,984 emergency stroke patients in 2017-2018, both cold and hot effects were observed and weakened after correction for other environmental factors. Compared to the reference temperature, in the multi-factor model, extreme cold (-10°C) reached a maximum relative risk (RR) of 1.20 [95% Confidence Interval (CI): 1.09, 1.32] at lag 14 days, and extreme hot (30°C) had a maximum RR of 1.07 (95% CI: 1.04, 1.11) at lag 6 days. The cumulative effect of extreme cold reached a maximum of 2.02 (95% CI: 1.11, 3.67) at lag 0-14 days, whereas the cumulative effect of extreme hot temperature is greatest at lag 0-10 days, but no statistically significant effect was found. In addition, ischemic stroke patients, the elderly, and males were more susceptible to the effects of cold temperature. CONCLUSIONS: There is a non-linear relationship between ambient temperature and stroke occurrence, with cold temperature having a greater and longer-lasting impact than hot temperature.
By using 64,270 daily observations from a large hospital in Guangzhou between 2017 and 2019, we analyzed the impact of extreme temperature on the health of newborns via OLS regression with time fixed effect. Given that the short-term temperature change can be regarded as exogenous and random, solving the potential endogenous problem is critical. We find that extreme temperature negatively affects the health of newborns. The Apgar score, an index for evaluating neonatal health, decreases by 0.008 (0.029%) when the duration of extreme temperature events increases by a day. A series of robustness checks verify the reliability of this negative effect. Extreme temperature also has a particularly serious effect on the health of newborns whose mothers have poor education. By gradually extending the observation period, we find that the effect of extreme temperature on neonatal health is mainly concentrated 1-6 weeks before delivery, whereas the effect of extreme temperature on hospitalization cost is mainly concentrated 4-8 weeks before delivery. This paper provides a valuable reference for evaluating the health and social costs of extreme weather, and our findings are conducive to the construction of climate resilient health systems, especially in Guangzhou.
BACKGROUND: Previous studies have shown negative relationships between ambient temperature and blood pressure (BP). However, few studies estimated temperature-adjusted hypertension prevalence and control rate in different population. OBJECTIVE: To estimate the effects of temperature on BP, and further calculate temperature-adjusted hypertension prevalence and control rate. METHODS: Meteorological and BP data in Guangdong Province from 2004 to 2015 were collected. There were 31 351 participants aged 18 years and over. Based on 2018 European society Arterial Hypertension Guidelines, participants were divided into normotensive patients (n = 23 046), known hypertensive patients (n = 2807), and newly detected hypertensive patients (n = 5498). We first used generalized additive model to establish the nonlinear relationship between daily mean temperature and BP, and then calculated the linear effects of temperature on BP among populations with different hypertension status. Finally, we calculated the temperature-adjusted hypertension prevalence and control rate. RESULTS: Generally, there is an inverse relationship between temperature and BP. For a 1 °C increase in temperature, the decreased SBPs for normotensive patients, newly detected hypertensive patients, and known hypertensive patients were 0.37 [95% confidence interval (CI): -0.40, -0.33] mmHg, 0.21 (95% CI: -0.32, -0.10) mmHg and 0.81 (95% CI: -1.02, -0.59) mmHg, while reduced DBPs were 0.19 (95% CI: -0.21, -0.16) mmHg, 0.01 (95% CI: -0.06,0.08) mmHg, and 0.44 (95% CI: -0.56, -0.32) mmHg, respectively. At 5, 10, 15, 20, and 25 °C, the hypertension prevalence rates were 32.5, 29.7, 27.7, 26.0, and 25.0%, respectively, and the control rates were 12.0, 17.5, 23.5, 30.1, and 37.1%, respectively. CONCLUSION: Low temperature increased BP for all populations, especially for known hypertensive patients, which makes hypertension prevalence increase and control rate decrease if temperature reduce. Our findings suggest that temperature should be considered in hypertension clinic management and epidemiological survey.
BACKGROUND: Few studies have explored the role of ambient temperature in asthma exacerbation. OBJECTIVE: We aimed to explore the association of temperature with diurnal peak expiratory flow (PEF) variation and asthma exacerbation. METHOD: We developed a longitudinal study among asthmatic adults in 18 Chinese cities. Subjects recorded PEF in dynamic pulmonary function monitoring from 2017 to 2020. Linear mixed-effect model and generalized additive model with distributed non-linear models were used to assess the effect of temperature and temperature change between neighboring days (TCN) on diurnal PEF variation and the risk of asthma exacerbation. RESULT: We evaluated a total of 79,217 daily PEF monitoring records from 4467 adult asthmatic patients. There were significant increase of diurnal PEF variation and higher risk of asthma exacerbation with cold and sudden temperature drop. Compared with the referent temperature (99th percentile, 32 °C), exposure to moderate cold (25th percentile, 3 °C) and extreme cold (2.5th percentile, -7 °C) was associated with elevations of 1.28% and 1.16% in diurnal PEF variation over lag 0-2 days, respectively. The odds ratios of asthma exacerbation (determined by diurnal PEF variation >20%) at the two temperature cutoffs were 1.68 and 1.73. A sudden temperature drop (2.5th percentile of TCN, -5 °C) was associated with 1.13% elevation in diurnal PEF variation, and with increased risk of asthma exacerbation (odd ratio = 1.50) over lag 0-4 days. CONCLUSION: This large multicenter study provided the first-hand empirical evidence that cold temperature and a temperature drop may increase the risk of asthma exacerbation.
A high premium has been put on researching the effects of cold spells because of their adverse influence on people’s daily lives and health. The study aimed to find the most appropriate definition of the cold spell in Shenzhen and quantify the impact of cold spells on mortality. Based on the daily mortality data in Shenzhen from 2013 to 2017 and the meteorological and pollutant data from the same period, we quantified the effect of cold spells using eight different definitions in the framework of a distributed lag non-linear model with a quasi-Poisson distribution. In Shenzhen, low temperatures increase the risk of death more significantly than high temperatures (using the optimal temperature as the cut-off value). Comparing the quasi-Akaike information criterion value, attribution fraction (b-AF), and attribution number (b-AN) for all causes of deaths and non-accidental deaths, the optimal definition of the cold spell was defined as the threshold was 3rd percentile of the daily average temperature and duration for 3 or more consecutive days (all causes: b-AF = 2.31% [1.01-3.50%], b-AN = 650; non-accidental: b-AF = 1.92% [0.57-3.17%], b-AN = 471). For cardiovascular deaths, the best definition was the temperature threshold as the 3rd percentile of the daily average temperature with a duration of 4 consecutive days (cardiovascular: b-AF = 1.37% [0.05-2.51%], b-AN = 142). Based on the best definition in the model, mortality risk increased in cold spells, with a statistically significant lag effect occurring as early as the 4th day and the effect of a single day lasting for 6 days. The maximum cumulative effect occurred on the 14th day (all-cause: RR = 1.54 [95% CI, 1.20-1.98]; non-accidental: RR = 1.43 [95% CI, 1.11-1.84]; cardiovascular: RR = 1.58 [95% CI, 1.00-2.48]). The elderly and females were more susceptible to cold spells. Cold spells and their definitions were associated with an increased risk of death. The findings of this research provide information for establishing an early warning system, developing preventive measures, and protecting susceptible populations.
Buildings made of snow and ice in severely cold areas can provide people with tourist experiences. Utilizing natural resources in an appropriate manner such as constructing energy efficient residential buildings that are suited to local climate conditions is important for maintaining indoor thermal comfort, creating ecologically living spaces, and reducing energy consumption. In this study, an igloo was built in the traditional manner at Harbin Institute of Technology to detect the heat transfer mechanism of ice and snow, and indoor thermal comfort in an extremely cold region of China. The thermal benefits of the igloo were investigated based on field measurements. Periodic heat transfer theory was applied to study the heat transfer mechanism in the igloo wall and human thermal comfort was analyzed in the chamber and under ambient conditions. The results showed the following. (1) The air temperature and relative humidity were higher and more stable in the chamber without any heating measures. (2) The air temperature was about 4 degrees C higher in the chamber than the ambient temperature. (3) The maximum snow depth where the ambient temperature affected the chamber temperature was 200 mm. (4) The igloo provided a more comfortable thermal environment compared with the outdoor conditions. These findings may provide the basis for understanding the thermal benefit of igloos based on the utilization of natural resources. Theoretically and practically, our results may provide an experimental basis for studying the heat transfer mechanism to facilitate the establishment of design and construction standards for snow and ice buildings.
OBJECTIVES: We aimed to investigate the acute effect of extreme cold weather on circulatory disease mortality of older adults in Jinan, with individual and regional-scale characteristics as subgroup analyses to further identify vulnerable populations. METHODS: This study contained the death data of Jinan from 2011 to 2020 (Nov-Mar). A time-stratified case-crossover method was used to estimate the effects of extreme cold weather and lags 0-8 days, controlling for holiday and relative humidity. To evaluate the impact of different durations and thresholds of extreme cold weather, we considered 4 cold day and 12 cold wave definitions RESULTS: Our results showed an increase in circulatory disease deaths under several definitions. The number of older adults died of circulatory diseases totaled 92,119 during the study period. In the definitions of cold day, the maximum significant effect ranging from 1.08 (95% CI: 1.03,1.14) to 1.13 (95% CI: 1.04,1.24) and appeared on Lag5 or Lag6. In the definitions of cold wave, the maximum significant effect ranging from 1.07 (95% CI: 1.02, 1.12) to 1.14 (95% CI: 1.03, 1.25). The cold effect is mainly attributable to cold day rather than an added effect related to the duration. Our research confirmed that extreme cold weather had a stronger impact on women [maximum effects with an OR of 1.21 (95% CI: 1.08, 1.36) in P1, 1.19 (95% CI: 1.05, 1.36) in M12)], and the effect gradient increased with age. CONCLUSIONS: Our findings support the evidence on the impact of extreme cold weather on circulatory disease mortality and provide a basis for policymakers to select target groups to develop policies and reduce the public health burden.
Background: Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death in China. Although numerous studies have been conducted to determine the risk factors for COPD mortality such as ambient air pollution, the results are not fully consistent. Methods: This study included mortality analysis and a case-control design by using the data extracted from the Mortality Registration System in Jiading District, Shanghai. Traditional logistic regression, geographically weighted logistic regression (GWLR), and spatial scan statistical analysis were performed to explore the geographic variation of COPD mortality and the possible influencing factors. Results: Traditional logistic regression showed that extreme lower temperature in the month prior to death, shorter distance to highway, lower GDP level were associated with increased COPD mortality. GWRL model further demonstrated obvious geographical discrepancies for the above associations. We additionally identified a significant cluster of low COPD mortality (OR = 0.36, P = 0.002) in the southwest region of Jiading District with a radius of 3.55 km by using the Bernoulli model. The geographical variation in age-standardized mortality rate for COPD in Jiading District was explained to a certain degree by these factors. Conclusion: The risk of COPD mortality in Jiading District showed obvious geographical variation, which were partially explained by the geographical variations in effects of the extreme low temperature in the month prior to death, residential proximity to highway, and GDP level.
Previous studies have reported that daily average temperature is connected with respiratory diseases (RD), but proof is limited for the influence of the extreme low temperature on RD in Lanzhou, a northwestern China of temperate area. Generalized additive model (GAM) was built in this work to describe the relationship between daily mean temperature and RD in Lanzhou, China from 2012 to 2017. The results indicated that the exposure-response curve was inverse J-shaped, showing the lower the temperature, the larger the relative risk (RR). The RR of daily emergency room (ER) admissions in P5 extreme low temperature (the temperature below the fifth percentile, etc.) was larger than that in P10. The P5 extreme low temperature has the strongest effect at lag 0, and the RRs were 1.043 (95% CI: 1.030, 1.055) for the total, 1.031 (95% CI: 1.015, 1.046) for males and 1.058 (95% CI: 1.039, 1.077) for females. For different age groups, the largest RRs were 1.026 (95% CI: 1.013, 1.039) for the children (age < 16 years) at lag 5, 1.057 (95% CI: 1.030, 1.085) for the young adults (aged 16-45 years), 1.060 (95% CI: 1.023, 1.099) for the middle-aged (aged 46-60 years) and 1.121 (95% CI: 1.077, 1.166) for the elderly group of age > 60 years. Meanwhile, females and the elderly were more vulnerable to extreme temperature. The results could strengthen the scientific evidence of effects of extreme low temperature on RD in temperate areas.
Ambient cold is associated with substantial population attributable fraction of mortality in China, and respiratory health is vulnerable to cold exposure. This study aimed to examine the effect of cold spells on risk of deaths from chronic obstructive pulmonary disease (COPD). We collected daily data on deaths from COPD and climatic factors from 1 January 2016 to 31 December 2019 in 13 cities of Jiangsu Province, China. We used a quasi-Poisson generalized linear model coupled with a distributed lag non-linear model to quantify the association between risk of COPD deaths and exposure to cold spells (defined as 2 or more consecutive days with mean temperature ≤ 5(th) percentile of daily mean temperature distribution in cold months). Stratification analyses by age, sex, education, and occupation were undertaken to identify vulnerable subgroups. The results suggested that exposure to cold spells was associated with a higher risk of COPD deaths in Lianyungang (relative risk (RR): 1.70; 95% confidence interval (CI): 1.31, 2.21), Nanjing (RR: 1.54; 95% CI: 1.16, 2.04), Nantong (RR: 1.97; 95% CI: 1.68, 2.31), Suzhou (RR: 1.97; 95% CI: 1.55, 2.50), Suqian (RR: 1.68; 95% CI: 1.23, 2.29), Taizhou (RR: 1.70; 95% CI: 1.32, 2.19), Wuxi (RR: 1.99; 95% CI: 1.53, 2.60), Xuzhou (RR: 1.71; 95% CI: 1.01, 2.90), Yancheng (RR: 1.78; 95% CI: 1.53, 2.06), Yangzhou (RR: 2.78; 95% CI: 2.06, 3.76), and Zhenjiang (RR: 1.79; 95% CI: 1.26, 2.55). All subgroups seemed to be vulnerable to the effect of cold spells. The recommendation of this study is that individuals with pre-existing COPD, regardless of age, sex, education, or occupation, should be made aware of the health risk posed by cold spells and should be encouraged to take cold adaptation actions before cold season arrives. The main limitation of this study is that it is subject to ecological fallacy.
BACKGROUND: Pulmonary embolism (PE) is an important cause of death and its seasonality has long been observed. Very few epidemiological studies have explored the potential role of ambient temperature in PE symptom onset, especially at the hourly level. METHODS: We conducted a time-stratified case-crossover study among 17,903 PE patients with hourly onset of symptom from 1590 hospitals across China between January 2015 and September 2020. Conditional logistic regression model combined with distributed lag non-linear models were used to explore the associations between hourly ambient temperature and PE symptom onset. The attributable fractions due to non-optimum temperature were calculated. RESULTS: The exposure-response relationship curve was inverse and almost linear. Lower temperature was significantly associated with higher risk of PE symptom onset when temperature was below 18 °C. This risk occurred immediately at the same hour, attenuated thereafter, and became nonsignificant at approximately 72 h after exposure. Compared with the referent temperature (P(99), 34.1 °C), the odds ratio of PE symptom onset associated with extremely low temperature (P(1), -16.1 °C) over lag 0-72 h was 1.63 (95%CI: 1.23, 2.16). Low temperature may account for 16.19 % of the symptom onset nationally with higher proportion in the south of China. The effects were stronger in older adults, males, and cold seasons. CONCLUSIONS: We provided the first-hand robust evidence that transient exposure (at the hourly level) to low temperature might trigger the symptom onset of PE and constitute a considerable burden for PE patients. Targeted protections and health education are needed for susceptible populations.
BACKGROUND: Many studies have investigated the devastating health effects of heat waves, but less is known about health risks related to cold spells, despite evidence that extreme cold may contribute to a larger proportion of deaths. OBJECTIVES: We aimed to systematically investigate the association between cold spells and mortality in Japan. METHODS: Daily data for weather conditions and 12 common causes of death during the 1972-2015 cold seasons (November-March) were obtained from 47 Japanese prefectures. Cold spells were defined as ≥ 2 consecutive days with daily mean temperatures ≤ 5th percentile for the cold season in each prefecture. Quasi-Poisson regression was combined with a distributed lag model to estimate prefecture-specific associations, and pooled associations at the national level were obtained through random-effects meta-analysis. The potential influence of cold spell characteristics (intensity, duration, and timing in season) on associations between cold spells and mortality was examined using a similar two-stage approach. Temporal trends were investigated using a meta-regression model. RESULTS: A total of 18,139,498 deaths were recorded during study period. Mortality was significantly higher during cold spell days vs. other days for all selected causes of death. Mortality due to age-related physical debilitation was more strongly associated with cold spells than with other causes of death. Associations between cold spells and mortality from all causes and several more specific outcomes were stronger for longer and more intense cold spells and for cold spells earlier in the cold season. However, although all outcomes were positively associated with cold spell duration, findings for cold spell intensity and seasonal timing were heterogeneous across the outcomes. Associations between cold spells and mortality due to cerebrovascular disease, cerebral infarction, and age-related physical debility decreased in magnitude over time, whereas temporal trends were relatively flat for all-cause mortality and other outcomes. DISCUSSION: Our findings may have implications for establishing tailored public health strategies to prevent avoidable cold spell-related health consequences. https://doi.org/10.1289/EHP7109.
Deleterious effect of cold on overall mortality is well-established. We studied associations between the air temperature and the number f ambulance calls for asthma in Nur-Sultan, Kazakhstan – the second coldest capital in the world. Daily counts of ambulance calls for asthma in Nur-Sultan for the cold seasons (October-March) 2006-2010 were obtained from the Municipal Ambulance Station. Associations between the number of calls and mean and minimum apparent temperatures (average for lags 0-15) were studied using first-order Poisson auto-regression models controlling for wind speed and effects of month, year, weekends and holidays. Altogether, there were 7373 ambulance calls for asthma during the study period. An inverse association between minimum apparent temperature and the number of calls was observed for the age-group 60 years and older. A decrease of the minimum apparent temperature by 1 °C was associated with an increase in the number of calls by 1.7% (95% CI: 0.1%-3.3%) across the whole temperature spectrum. No associations in other age groups were found. Our results suggest an inverse association between the average 15-day lag minimum apparent temperature and the number of ambulance calls during the cold season in Nur-Sultan, but this is limited to the oldest age-group.
BACKGROUND: Emerging evidence supports an association between heat exposure and acute kidney injury (AKI). However, there is a paucity of studies on the association between cold exposure and AKI. OBJECTIVE: We aimed to investigate the associations of cold exposure with hospital admission and mortality due to AKI and to explore whether these associations were influenced by age and sex. METHODS: Information on daily counts of hospital admission and mortality due to AKI in 16 regions of Korea during the cold seasons (2010-2019) was obtained from the National Health Insurance Service (a single national insurer providing universal health coverage) and Statistics Korea. Daily mean temperature and relative humidity were calculated from hourly data obtained from 94 monitoring systems operated by the Korean Meteorological Administration. Associations of low temperatures (<10th percentile of daily mean temperature) and cold spells (≥2 consecutive days with <5th percentile of daily mean temperature) up to 21 days with AKI were estimated using quasi-Poisson regression models adjusted for potential confounders (e.g., relative humidity and air pollutants) with distributed lag models and univariate meta-regression models. RESULTS: Low temperatures were associated with hospital admission due to AKI [relative risk (RR) = 1.12, 95 % confidence interval (CI): 1.09, 1.16]. Cold spells were associated with hospital admission (RR = 1.87, 95 % CI: 1.46, 2.39) and mortality due to AKI (RR = 4.84, 95 % CI: 1.30, 17.98). These associations were stronger among individuals aged ≥65 years than among those aged <65 years. CONCLUSION: Our results underscore the need for the general population, particularly the elderly, physicians, and other healthcare providers to be more vigilant to cold exposure, given the risk of AKI. Government agencies need to develop specific strategies for the prevention and early detection of cold exposure-related AKI.
BACKGROUND: Climate change is predicted to increase the frequency, intensity, and duration of extreme cold events in the mid-latitudes. However, although diabetes is one of the most critical metabolic diseases due to its high and increasing prevalence worldwide, few studies have investigated the short-term association between cold exposure and diabetes-related outcomes. OBJECTIVE: The aim of this study was to investigate the associations between cold spells and their characteristics (intensity, duration, and seasonal timing) and hospital admission and mortality due to diabetes. METHODS: This study used claims data from the National Health Insurance Service and cause-specific mortality data from Statistics Korea (2010-2019). Cold spells were defined as ≥2 consecutive days with a daily mean temperature lower than the region-specific 5th percentile during the cold season (November-March). Quasi-Poisson regressions combined with distributed lag models were used to assess the associations between exposures and outcomes in 16 regions across the Republic of Korea. Meta-analyses were conducted to pool the region-specific estimates. RESULTS: Exposure to cold spells was associated with an increased risk of hospital admission [relative risk (RR) = 1.45, 95% confidence interval (CI): 1.26, 1.66] and mortality (RR = 2.02, 95% CI: 1.37, 2.99) due to diabetes. The association between cold spells and hospital admission due to diabetes was stronger for cold spells that were more intense, longer, and occurred later during the cold season. The association between cold spells and diabetes-related mortality was stronger for more intense and longer cold spells. CONCLUSION: This study emphasizes the importance of developing effective interventions against cold spells, including education on the dangers of cold spells and early alarm systems. Further studies are needed to create real-world interventions and evaluate their effectiveness in improving diabetes-related outcomes.
Extremely cold events have occurred frequently around the world in the past few years, and people will inevitably be exposed to extremely cold environments during certain activities in modern society. Cold stress seriously threatens human health and safety. The purpose of this study was to study the physiological responses and thermal sensation of humans exposed to extreme cold. Twelve healthy males were exposed to a cold (-20 degrees C) environment in a climate chamber for 30 min after a preconditioning phase. This cold exposure was followed by 40 min of recovery at 24 degrees C. Thermal sensation and physiological parameters, including core temperature, local skin temperature, blood pressure, and heart rate, were recorded throughout the entire process. The results show that the ear is the most sensitive to ambient temperature changes. Blood pressure increased 17.6% within a minute of cold exposure. The average heart rate continued to drop in each period. Establishing a transition space can relieve the pressure stimulus of a large temperature difference. There are functional correlations between the local skin temperature and thermal perception, and the ear exhibits the best correlation. The asymmetry of thermal sensation in extremely cold environments is eliminated when the temperature difference exceeds a certain threshold between 40 degrees C and 44 degrees C. The results of this study are of great significance for extreme cold protection.
As the global climate continues to warm, there is an increased focus on heat, but the role of low temperatures on health has been overlooked, especially for developing countries. Methods We collected the admission data of childhood asthma in 2013-2016 from Anhui Provincial Children’s Hospital, as well as meteorological data from the Meteorological Bureau for the study period and collected data of pollutants from 10 monitoring stations around Hefei city. Poisson’s generalized additive model (GAM) combined with a distributed lag non-linear model (DLNM) was used to estimate the short-term effects of cold spell on childhood asthma in cold seasons (November to March). 16 definitions of cold spells were clearly compared, which combining 4 temperature indexes (daily minimum and mean temperature; daily minimum and mean apparent temperature), 2 temperature thresholds (2.5th and 5th) and 3 durations of at least 2-4 days. We then have an analysis of the modifying effect of characteristics of cold spells and individuals(gender and age), with a view to discovering the susceptible population to cold spell. Results There was significant association between cold spells and admission risk for childhood asthma. And the definition, in which daily minimum apparent temperature falls below 5th percentile for at least 3 consecutive days, produced the optimum model fit performance. Based on this optimal fit we found that, for the total population, the effect of cold spell lasted approximately five days (lag1-lag5), with the largest effect occurring in lag 3 (RR = 1.110; 95% CI: 1.052-1.170). In subgroup analysis, the cumulative effect of lag0-7 was higher in males and school-age children than in females and other age groups, respectively. In addition, we found that the effect of is higher as the duration increases. Conclusion This study suggests an association between cold spell and childhood asthma, and minimum AT may be a better indicator to define the cold spells. Boys and school-age children are more vulnerable to cold spell. And one of our very interesting findings is that if a cold spell lasts for several days, the impact of the cold spell on those later days is likely to be greater than that of the previous days. In conclusion, we should pay more attention to the protection of boys and school-aged children in our future public health protection and give more attention to those cold spells that last longer. Therefore, we recommend that schools and health authorities need to take targeted measures to reduce the risk of asthma in children during the cold spell.
Ambient temperature is an important contributor to mortality burden worldwide, most of which is from cold exposure. However, little is known about the cold impact on life expectancy loss. This paper aimed to estimate cold-related life expectancy loss from cause-, age-, and gender-specific cardiovascular and respiratory diseases. Daily deaths from cardiovascular and respiratory diseases and weather records were acquired for Hong Kong, China during 2000-2016. Years of life lost (YLL) that considers life expectancy at the time of death was calculated by matching each death by age and sex to annual life tables. Using a generalized additive model that fits temperature-YLL association, we estimated loss of years in life expectancy from cold. Cold was estimated to cause life expectancy loss of 0.9 years in total cardiovascular disease, with more years of loss in males than in females and in people aged 65 years and older than in people aged up to 64 years. Cold-related life expectancy loss in total respiratory diseases was 1.2 years, with more years of loss in females than in males and comparable years of loss in people aged up to 64 years and in people aged 65 years and older. Among cause-specific diseases, we observed the greatest life expectancy loss in pneumonia (1.5 years), followed by ischaemic heart disease (1.2 years), COPD (1.1 years), and stroke (0.3 years). Between two periods of 2000-2007 and 2008-2016, cold-related life expectancy loss due to cardiovascular disease did not decrease and cold-related life expectancy loss due to respiratory disease even increased by five times. Our findings suggest an urgent need to develop prevention measures against adverse cold effects on cardiorespiratory disease in Hong Kong.
BACKGROUND: Previous studies have demonstrated the seasonal variations of non-variceal upper gastrointestinal bleeding (UGIB), but there is scanty data on lower gastrointestinal bleeding (LGIB) and the association with other meteorological parameters. METHODS: We included all patients hospitalized for UGIB and LGIB between 2009 and 2018 in Hong Kong. The monthly age-standardized and sex-standardized GIB incidences were fitted to meteorological data including average temperature (AT), maximum temperature (MaxT), minimum temperature (MinT), temperature range (TR), average precipitation, average atmospheric pressure (AtomP), and average relative humidity after adjusting for prescriptions of aspirin, proton pump inhibitors, and Helicobacter pylori eradication therapy using the autoregressive integrated moving average model. RESULTS: Despite a gradual decline in UGIB incidences, the incidences of UGIB were still higher in winter months. The incidence and fluctuation of both UGIB and LGIB were higher in the older age groups, especially those ≥80 years. The seasonality was only identified in those ≥60 years for UGIB, and only in those ≥80 years for LGIB. UGIB incidence was inversely associated with AT, MaxT, and MinT, but positively associated with TR and AtomP. LGIB was also significantly associated with AT, MaxT, MinT, and AtomP. CONCLUSION: Despite the changes in GIB incidences, the seasonal patterns of GIB were still marked in the elderly. With the aging population, the impacts of seasonal variations on GIB incidences could be considerable.
BACKGROUND: Previous studies have revealed the relationship between cold spells and morbidity and mortality due to respiratory diseases, while the detrimental effects of cold spells on the length of hospital stay and hospitalization expenses remain largely unknown. METHODS: We collected hospitalization data for respiratory diseases in 11 cities of Shanxi, China during 2017-2019. In each case, exposure to meteorological variables and air pollution was estimated by the bilinear interpolation approach and inverse distance weighting method, respectively, and then averaged at the city level. Cold spells were defined as the daily mean temperature below the 10(th), 7.5(th), or 5(th) percentiles for at least 2 to 5 consecutive days. We applied distributed lag non-linear models combined with generalized additive models to assess cumulative effects and harvesting effects. RESULTS: There were significant associations between cold spells and hospital admissions, length of hospital stay, and hospital expenses for respiratory diseases. Compared with the non-cold spell period, the overall (lag 0-21) cumulative risk of hospitalization for total respiratory diseases was 1.232 (95 % CI: 1.090, 1.394) on cold spell days, and the increased length of hospital stay and hospitalization expenses were 112.793 (95 % CI: 10.755, 214.830) days and 127.568 (95 % CI: 40.513, 214.624) thousand Chinese yuan. The overall cumulative risks of cold spells on total respiratory diseases and pneumonia were statistically significant. We further observed harvesting effects in the associations between cold spells and hospital admission, length of hospital stay, and hospitalization expenses for respiratory diseases. CONCLUSIONS: Cumulative cold-spell exposure for up to three weeks is associated with hospitalization, length of hospital stay, and hospital expenses for respiratory diseases. The observed harmful effects of cold spells on respiratory diseases can be partly attributable to harvesting effects.
AIMS: The incidence of acute aortic dissection (AAD) has been shown to have seasonal variation, but whether this variation can be explained by non-optimum ambient temperature and temperature change between neighbouring days (TCN) is not clear. METHODS AND RESULTS: We performed a time-stratified case-crossover study in the Registry of Aortic Dissection in China covering 14 tertiary hospitals in 11 cities from 2009 to 2019. A total of 8182 cases of AAD were included. Weather data at residential address were matched from nearby monitoring stations. Conditional logistic regression model and distributed lag nonlinear model were used to estimate the associations of daily temperature and TCN with AAD, adjusting for possible confounders. We observed an increase of AAD risk with lower temperature cumulated over lag 0-1 day and this association became statistically significant when daily mean temperature was below 24°C. Relative to the referent temperature (28°C), the odds ratios (ORs) of AAD onset at extremely low (-10°C) and low (1°C) temperature cumulated over lag 0-1 day were 2.84 [95% confidence interval (CI): 1.69, 4.75] and 2.36 (95% CI: 1.61, 3.47), respectively. A negative TCN was associated with increased risk of AAD. The OR of AAD cumulated over lag 0-6 days was 2.66 (95% CI: 1.76, 4.02) comparing the extremely negative TCN (-7°C) to no temperature change. In contrast, a positive TCN was associated with reduced AAD risk. CONCLUSION: This study provides novel and robust evidence that low ambient temperature and temperature drop between neighbouring days were associated with increased risk of AAD onset. KEY QUESTION: Incidence of acute aortic dissection (AAD) was reported to have seasonal trends, but it remains unclear whether non-optimum ambient temperature and temperature change between neighbouring days (TCN) is associated with AAD onset. KEY FINDING: Daily mean temperature lower than 24°C was significantly associated with increased risk of AAD at lag 0-1 day. A negative TCN (temperature drop) was associated with increased risk of AAD, whereas a positive TCN was associated with decreased risk. TAKE HOME MESSAGE: This multi-centre, case-crossover study provides novel and robust evidence that low ambient temperature and temperature drop between neighbouring days were associated with increased AAD risk.
BACKGROUND: The cold season seems to be a trigger for atrial fibrillation (AF). Some reports are controversial and demonstrate variability according to the climatic characteristics in different regions. OBJECTIVES: To analyze whether meteorological factors contribute to seasonal variation of exacerbation of AF diagnosed in patients referred to the emergency department (ED) of our hospital. METHODS: We retrospectively reviewed medical data of consecutive patients admitted to the ED with symptomatic acute onset AF from 1 January 2016 to 31 December 2018. We recorded the mean monthly outdoor temperature, barometric pressure, and relative humidity during the study period. RESULTS: During the study period, 1492 episodes of AF were recorded. New onset AF were 639 (42.8%) and paroxysmal atrial fibrillation (PAF) were 853 (57.2%) (P = 0.03). The number of overall admission of AF episodes was not distributed uniformly through the year. Incidence of AF episodes peaked during December and was lowest in June (P = 0.049). Of 696 episodes (46.6 %) the patients were hospitalized and for 796 (53.4%) the patients were discharged (0.01). The number of hospitalizations was not distributed uniformly through the year (P = 0.049). The highest number of hospitalizations happened in December and the lowest in May. Outdoor temperature and barometric pressure (but not relative humidity) may mediate a monthly fluctuation in AF episodes with highest number of ED visits in December and the lowest in June. CONCLUSIONS: Meteorological conditions influence exacerbation of AF episodes and hospitalization. Outdoor temperature and barometric pressure may mediate a monthly fluctuation in AF.
BACKGROUND: Cold significantly increases the risk of mortality. However, the health risks associated with cold spells, persistent and extreme cold temperature events, have yet to be investigated in detail. METHODS: Meteorological and mortality data was collated from 280 counties in China from 2013 through 2019. GLM (Generalized Linear Models) was used to calculate county-level exposure-response relationships for nine different cold spell definitions. Next, we estimated the exposure-response associations between cold spells and mortality in national, Southern, and Northern China. Based on exposure-response relationships, along with the population and mortality data, we then calculated the number of excess deaths due to the cold spell of 2839 counties across China in 2018. Then, we calculated the loss of VSL (value of a statistical life) in each province. RESULTS: We identified that P5day7 was the cold spell definition that was associated with the highest health in China. Compared with non-cold spell days, the risk of non-accidental mortality, circulatory mortality, and respiratory mortality, on cold spell days increased by 17.4% (95% confidence interval [CI]: 15.8%, 19.0%), 20.8% (95%CI: 18.8%, 23.0%), and 22.7% (95%CI: 19.5%, 25.9%) respectively at lag 7 day in the South. In the North, the risk increased by 13.0% (95% CI: 11.0%, 15.0%), 13.8% (95% CI: 11.4%, 16.2%), and 21.0% (95% CI: 16.6%, 25.6%), respectively. The number of related deaths in China were 57,783, 29,827, and 10,922. The corresponding VSLs were 229,195, 118,322, and 43,315 million CNY (Chinese Yuan), thus accounting for 0.25%, 0.13%, and 0.05% of national GDP (Gross Domestic Product). CONCLUSION: Cold spells have caused a severe epidemiological and economic burden in China. South China should pay more attention to the health risks associated with cold spells.
The association between temperature and mortality has been widely investigated, however, studies on the effects of central heating on mortality risk are sparse. We applied a variant of difference-in-differences (DID) approach to assess the effects of central heating on winter mortality in China, and further analyzed the modification effect of central heating on the temperature-mortality association. Central heating was negatively associated with winter mortality (OR: 0.42, 95% CI: 0.39, 0.46) with higher effects on females and the elderly. Compared with cardiovascular or cerebrovascular diseases, central heating had a much greater effect on respiratory diseases. Every week less in central heating duration was associated with a 3.32% (95% CI: 3.03%, 3.61%) increased risk in total mortality. We found the temperature effect was much more pronounced among the locations without central heating (ER: 5.01%, 95% CI: 4.68%, 5.34%) than those with central heating (ER: 0.01%, 95% CI: -0.74%, 0.75%). The analysis suggests that central heating significantly decreases winter mortality in northern China, which may partly be achieved by attenuating the mortality caused by temperature. Therefore, central heating should be developed in some regions of southern China to reduce the mortality risk of low temperature in winter.
Low-temperature weather accompanied by strong chill wind is considered as a great risk factor for human health in winter, especially in some extreme weather conditions. Based on the observation data and the NCEP/NCAR reanalysis data of air temperature and wind velocity in 1961–2019, the warming pause of wind chill temperature (WCT) in the 21st century in China is first revealed in this paper. A significant increasing trend of WCT is found during 1961–1999 (P1), and a slight decreasing trend in 1999–2019 (P2) is detected by a 21 year running trend analysis. The extreme cold WCT day (WCD) with the WCT index below the 10th percentile also shows a decreasing trend in P1 but a slight increasing trend in P2. Both the WCT and the extreme WCD consistently display the warming pause in seven climatic regions in China. That means the slowdown or even decrease of human bioclimatic temperature in recent two decades may lead to an increasing risk of frostbite and other cold-related diseases in the country. Both the decreasing trend of mean temperature and the increasing trend of the wind speed contribute to the slowdown of the human-perceived warming in the 21st century, and this conjoint contribution could be linked to the East Asian winter monsoon circulations over Siberia, i.e. the Siberian high. The variation of averaged sea level pressure over the central region of the Siberian high shows high consistency with both the WCT and the extreme WCD in the whole study period, by a decreasing rate of −1.28 hPa per decade in P1 and an increasing rate of 1.26 hPa per decade in P2.
BACKGROUND: Few multicity studies have evaluated the association between cold spells and mortality risk and burden. OBJECTIVES: We aimed to estimate the association between cold spells and cause-specific mortality and to evaluate the mortality burden in China. METHODS: We conducted a time-series analysis with a nationally representative Disease Surveillance Points System database during the cool seasons spanning from 2013 to 2015 in 272 Chinese cities. We used 12 cold-spell definitions and overdispersed generalized additive models with distributed lag models to estimate the city-specific cumulative association of cold spells over lags of 0-28 d. We controlled for the nonlinear and lagged effects of cold temperature over 0-28 d to evaluate the added effect estimates of cold spell. We also quantified the nationwide mortality burden and pooled the estimated association at national and different climatic levels with meta-regression models. RESULTS: For the cold-spell definition of daily mean temperatures of ≤ 5th percentile of city-specific daily mean temperature and duration of ≥ 4 consecutive d, the relative risks (i.e., risk ratios) associated with cold spells were 1.39 [95% confidence interval (CI): 1.15, 1.69] for non-accidental mortality, 1.66 (95% CI: 1.20, 2.31) for coronary heart disease mortality, 1.49 (95% CI: 1.12, 1.97) for stroke mortality, and 1.26 (95% CI: 0.85, 1.87) for chronic obstructive pulmonary disease mortality. Cold spells showed a maximal lagged association of 28 d with the risks peaked at 10-15 d. A statistically significant attributable fraction (AF) of non-accidental mortality [2.10% (95% CI: 0.94%, 3.04%)] was estimated. The risks were higher in the temperate continental and the temperate monsoon zones than in the subtropical monsoon zone. The elderly population was especially vulnerable to cold spells. DISCUSSION: Our study provides evidence for the significant relative risks of non-accidental, cardiovascular, and respiratory mortality associated with cold spells. The findings on vulnerable populations and differential risks in different climatic zones may help establish region-specific forecasting systems against the hazardous impact of cold spells. https://doi.org/10.1289/EHP9284.
BACKGROUND: There is a paucity of studies investigating extreme cold events and asthma exacerbations. This study examined whether an association exists between cold spells and daily hospital admissions for asthma in Beijing, China from 2012 to 2016. METHODS: Daily hospital admissions for asthma, meteorological variables and air quality data were collected during 2012-2016 in Beijing. A cold spell was defined as a period of at least two consecutive days with the daily mean temperature below or at the 5th percentile (-7 °C) in cold seasons (November to March) during the study period. We applied a time-series design using quasi-Poisson regression combined with a distributed lag model to estimate the risk of asthma hospital admissions associated with cold spells. Stratified analyses by gender and age groups were conducted to identify the potential susceptible subpopulations to cold spells. We also explored the effect modification by air quality by dividing the daily air quality index (AQI) into two levels (high and low) based on the median value. RESULTS: Cold spells increased the risk of asthma hospital admissions, with the maximum cumulative relative risk (CRR) over three weeks (Lag0-21) in the total population. The highest single-day relative risk (RR) was found on the days of cold spells (Lag0) with the RR = 1.059 (95% CI: 1.008-1.113), and the CRR at Lag0-21 was 1.333 (95% CI: 1.049-1.693). Across different gender and age groups, younger people (<65 years) were more sensitive to cold spells. No significant effect modification by AQI was detected. CONCLUSION: Short-term exposure to cold spells is associated with an increased risk of hospital admissions for asthma in Beijing. During the cold spells, younger people aged <65 years were at particular risk for asthma exacerbations. Our results suggest that extreme cold events have a significant impact on asthma.
WHAT IS ALREADY KNOWN ABOUT THIS TOPIC? In recent years, climate change may lead to an increase in cold spells in the middle latitudes, and there is a positive correlation between cold spells and population mortality. WHAT IS ADDED BY THIS REPORT? The acute response period and the vulnerable population were identified under the optimal definition of cold spells, and the mortality burden caused by cold spells was estimated. WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICE? This research would provide evidence on the acute mortality effects of cold spells in southern China. Therefore, vulnerable populations, especially the elderly, should take timely measures to reduce the health damage caused by cold spells, especially in the first week after cold waves.
Cold spells have been associated with specific diseases. However, there is insufficient scientific evidence on the effects of cold spells on out-of-hospital cardiac arrest (OHCA). Data on OHCA cases and on meteorological factors and air pollutants were collected between 2013 and 2020. We adopted a quasi-Poisson generalized additive model with a distributed lag nonlinear model (DLNM) to estimate the effect of cold spells on daily OHCA incidence. Backward attributable risk within the DLNM framework was calculated to quantify the disease burden. We compared the effects and OHCA burden of cold spells using nine definitions. The risks of different cold spells on OHCA increased at higher intensities and longer durations. Based on Akaike’s information criterion for the quasi-Poisson regression model and the attributable risk, the optimal cold spell was defined as a period in the cold month when the daily mean temperature was below the 10th percentile of the temperature distribution in the study period for at least 2 days. The single-day effect of the optimal cold spell on OHCA occurred immediately and lasted for approximately 1 week. The maximum single-day effect was 1.052 (95% CI: 1.018-1.087) at lag0, while the maximum cumulative effect was 1.433 (95% CI:1.148-1.788) after a 14-day lag. Men were more susceptible to cold spells. Young and middle-aged people were affected by cold spells similar to the elderly. Cold spells can increase the risk of OHCA with an approximately 1-week lag effect. Health regulators should take more targeted measures to protect susceptible populations during cold weather.
The rapid spread of dengue fever (DF) infection has posed severe threats to global health. Environmental factors, such as weather conditions, are believed to regulate DF spread. While previous research reported inconsistent change of DF risk with varying weather conditions, few of them evaluated the impact of extreme weather conditions on DF infection risk. This study aims to examine the short-term associations between extreme temperatures, extreme rainfall, and DF infection risk in South and Southeast Asia. A total of 35 locations in Singapore, Malaysia, Sri Lanka, and Thailand were included, and weekly DF data, as well as the daily meteorological data from 2012 to 2020 were collected. A two-stage meta-analysis was used to estimate the overall effect of extreme weather conditions on the DF infection risk. Location-specific associations were obtained by the distributed lag nonlinear models. The DF infection risk appeared to increase within 1-3 weeks after extremely high temperature (e.g. lag week 2: RR = 1.074, 95 % CI: 1.022-1.129, p = 0.005). Compared with no rainfall, extreme rainfall was associated with a declined DF risk (RR = 0.748, 95 % CI: 0.620-0.903, p = 0.003), and most of the impact was across 0-3 weeks lag. In addition, the DF risk was found to be associated with more intensive extreme weathers (e.g. seven extreme rainfall days per week: RR = 0.338, 95 % CI: 0.120-0.947, p = 0.039). This study provides more evidence in support of the impact of extreme weather conditions on DF infection and suggests better preparation of DF control measures according to climate change.
BACKGROUND: The effects of extreme temperature on infectious diseases are complex and far-reaching. There are few studies to access the relationship of pulmonary tuberculosis (PTB) with extreme temperature. The study aimed to identify whether there was association between extreme temperature and the reported morbidity of PTB in Shandong Province, China, from 2005 to 2016. METHODS: A generalized additive model (GAM) was firstly conducted to evaluate the relationship between daily reported incidence rate of PTB and extreme temperature events in the prefecture-level cities. Then, the effect estimates were pooled using meta-analysis at the provincial level. The fixed-effect model or random-effect model was selected based on the result of heterogeneity test. RESULTS: Among the 446,016 PTB reported cases, the majority of reported cases occurred in spring. The higher reported incidence rate areas were located in Liaocheng, Taian, Linyi and Heze. Extreme low temperature had an impact on the reported incidence of PTB in only one prefecture-level city, i.e., Binzhou (RR = 0.903, 95% CI: 0.817-0.999). While, extreme high temperature was found to have a positive effect on reported morbidity of PTB in Binzhou (RR = 0.924, 95% CI: 0.856-0.997) and Weihai (RR = 0.910, 95% CI: 0.843-0.982). Meta-analysis showed that extreme high temperature was associated with a decreased risk of PTB (RR = 0.982, 95% CI: 0.966-0.998). However, extreme low temperature was no relationship with the reported incidence of PTB. CONCLUSION: Our findings are suggested that extreme high temperature has significantly decreased the risk of PTB at the provincial levels. The findings have implications for developing strategies to response to climate change.
The aim of this study was to explore the effect of temperature on tuberculosis (TB) incidence using the distributed lag non-linear model (DLNM) from 2017 to 2021 in Kashgar city, the region with higher TB incidence than national levels, and assist public health prevention and control measures. From January 2017 to December 2021, a total of 8730 cases of TB were reported, with the higher incidence of male than that of female. When temperature was below 1 °C, it was significantly correlated with TB incidence compared to the median observed temperature (15 °C) at lag 7, 14, and 21, and lower temperatures showed larger RR (relative risk) values. High temperature produced a protective effect on TB transmission, and higher temperature from 16 to 31 °C has lower RR. In discussion stratified by gender, the maximum RRs were achieved for both male group and female group at - 15 °C with lag 21, reporting 4.28 and 2.02, respectively. At high temperature (higher than 20 °C), the RR value of developing TB for female group was significantly larger than 1. In discussion stratified by age, the maximum RRs were achieved for all age groups (≤ 35, 36-64, ≥ 65) at - 15 °C with lag 21, reporting 3.20, 2.07, and 3.45, respectively. When the temperature was higher than 20 °C, the RR of the 36-64-year-old group and the ≥ 65-year-old group was significantly larger than 1 at lag 21, while significantly smaller than 1 for cumulative RR at lag 21, reporting 0.11, 95% confidence interval (CI) (0.01, 0.83) and 0.06, 95% CI (0.01, 0.44), respectively. In conclusion, low temperature, especially in extreme level, acts as a high-risk factor inducing TB transmission in Kashgar city. Males exhibit a significantly higher RR of developing TB at low temperature than female, as well as the elderly group in contrast to the young or middle-aged groups. High temperature has a protective effect on TB transmission in the total population, but female and middle-aged and elderly groups are also required to be alert to the delayed RR induced by it.
INTRODUCTION: Numerous studies have reported the modification of particulate matters (PMs) on the association between cold temperature and health. However, it remains uncertain whether the modification effect may vary by size of PMs, especially in Shandong Province, China where the disease burdens associated with cold temperature and PMs are both substantial. This study aimed to examine various interactive effects of cold exposure and ambient PMs with diameters ≤1/2.5 μm (PM1 and PM2.5) on premature deaths in Shandong Province, China. METHODS: In the 2013-2018 cold seasons, data on daily mortality, PM1 and PM2.5, and weather conditions were collected from the 1822 sub-districts of Shandong Province. A time-stratified case-crossover study design was performed to quantify the cumulative association between ambient cold and mortality over lag 0-12 days, with a linear interactive term between temperature and PM1 and PM2.5 additionally added into the model. RESULTS: The mortality risk increased with temperature decline, with the cumulative OR of extreme cold (-16.9°C, the 1st percentile of temperature range) being 1.83 (95% CI: 1.66, 2.02), compared with the minimum mortality temperature. The cold-related mortality risk was 2.20 (95%CI: 1.83, 2.64) and 2.24 (95%CI: 1.78, 2.81) on high PM1 and PM2.5 days, which dropped to 1.60 (95%CI: 1.39, 1.84) and 1.60 (95%CI: 1.37, 1.88) on low PM1 and PM2.5 days. PM1 showed greater modification effect for per unit concentration increase than PM2.5. For example, for each 10?g/m3 increase in PM1 and PM2.5, the mortality risk associated with extreme cold temperature increased by 7.6% (95% CI: 1.3%, 14.2%) and 2.6% (95% CI: -0.7%, 5.9%), respectively. DISCUSSION: The increment of smaller PMs’ modification effect varied by population subgroups, which was particularly strong in the elderly aged over 75 years and individuals with middle school education and below. Specific health promotion strategies should be developed towards the greater modification effect of smaller PMs on cold effect.
El Plan Nacional de Predicción y Vigilancia de Fenómenos Meteorológicos Adversos (Meteoalerta) pretende facilitar la mejor y más actualizada información posible sobre los fenómenos atmosféricos adversos que se prevean, con un adelanto de hasta 72 horas. En ese sentido, uno de los avisos se corresponde con temperaturas mínimas y máximas extremas, con cuatro niveles básicos (de menor a mayor riesgo en modo semafórico) a partir del posible alcance de determinados umbrales: verde, amarillo, naranja y rojo. Estos umbrales se han establecido con criterios climatológicos cercanos al concepto de “poco o muy poco frecuente” y de adversidad, en función de la amenaza que puedan suponer para la población.
The purpose of the warnings on extreme temperatures is to prevent health problems resulting from cold and hot weather. The warnings are mainly intended for risk groups and people who work outdoors.
A heat wave warning is issued if stifling hot weather has been forecasted for some area in Finland. Criteria for cold weather warnings are based on wind chill index, which describes the combined effect of cold and wind. Warnings for hot and cold weather are for the next 5 days.
The Finnish Meteorological Institute gives warnings about highly slippery pedestrian weather. Then extra attention should be paid to the choice of footwear and slip guards should be worn. There may be wide local variations in walkway conditions. It depends on factors such as maintenance practices and the volume of traffic.
The warning specifies the cause and duration of slippery conditions. Between about seven and twenty warnings are issued each year per region.
Extreme cold events (“cold waves”) have disastrous impacts on ecosystem and human health. Evidence shows that these events will still occur under current increasing mean temperatures. Little research has been done on extreme cold events, especially in developing countries such as South Africa. These events pose a significant threat due to the low adaptive capacity, urgent development needs and relatively inadequate infrastructure in South Africa. This study presents annual and seasonal, spatial and temporal trend analyses of extreme cold temperature events for the period 1960-2016. We apply the World Meteorological Organisation Commission for Climatology and Indices Expert Team on Sector-Specific Climate Indices (ET-SCI) to South Africa for the first time, with comparison to the World Meteorological Organisation Expert Team on Climate Change Detection (ETCCDI) indices previously used in South Africa. The extreme cold indices are calculated using the RClimDex and ClimPACT, respectively. Trends were calculated using the non-parametric Mann-Kendall test, Spearman Rank Correlation Coefficient and Sen’s slope estimates. A decreasing trend is found for annual cold spell duration and cold wave frequency, at rates of 0.10 days.day(-1) and 0.02 events.day(-1), respectively. Seasonally, coldest day temperatures increased in autumn, with increases of 0.02 degrees C.day(-1) for the period 1960-2016. Regionally, increasing trends in annual cold spell duration days were evident in stations located in the Western Cape, Eastern Cape, North-West Province, at a rate of 0.03 days.day(-1). Increasing trends in cold waves were observed for stations in Northern Cape, Gauteng, KwaZulu-Natal and the Eastern Cape Province, at a rate of 0.01 events.day(-1). These results contribute to the awareness and recognition of the incidence and duration of cold extreme events in South Africa, seeing that studies suggest that anomalously cold events may persist in a warming world.
Cold spells have been associated with mortality from a few broad categories of diseases or specific diseases. However, there is a lack of data about the health effects of cold spells on mortality from a wide spectrum of plausible diseases which can reveal a more comprehensive contour of the mortality burden of cold spells. We collected daily mortality data in Guangzhou during 2010-2018 from the Guangzhou Center for Disease Control and Prevention. The quasi-Poisson generalized linear regression model mixed with the distributed lag non-linear model (DLNM) was conducted to examine the health impacts of cold spells for 11 broad causes of death groupings and from 35 subcategories in Guangzhou. Then, we examined the effect modification by age group (0-64 and 65+ years) and sex. Effects of cold spells on mortality generally delayed for 3-5 d and persisted up to 27 d. Cold spells were significantly responsible for increased mortality risk for most categories of deaths, with cumulative relative risk (RR) over 0-27 lagged days of 1.57 [95% confidence interval (CI): 1.48-1.67], 1.95 (1.49-2.55), 1.58 (1.39-1.79), 1.54 (1.26-1.88), 1.92 (1.15-3.22), 1.75, (1.14-2.68), 2.02 (0.78-5.22), 1.92 (1.49-2.48), 1.48 (1.18-1.85), and 1.18 (1.06-1.30) for non-accidental causes, cardiovascular diseases, respiratory diseases, digestive diseases, nervous system diseases, genitourinary diseases, mental diseases, endocrine diseases, external cause and neoplasms, respectively. The magnitudes of the effects of cold spells on mortality varied remarkably among the 35 subcategories, with the largest cumulative RR of 2.87 (1.72-4.79) estimated for pulmonary heart diseases. The elderly and females were at a higher risk of mortality for most diseases after being exposed to cold spells. Increased mortality from a wide range of diseases was significantly linked with cold spells. Our findings may have important implications for formulating effective preventive strategies and early warning response plans that mitigate the health burden of cold spells.
Concurrent meteorological droughts and consecutive cold events can significantly impact local ecosystems, socio-economies, and human health. The respective characteristics of droughts and cold extremes have been extensively studied, however, their concurrent extremes have received very little attention. In this study, we used the Huai River Basin as a case to build a magnitude index of concurrent meteorological droughts and consecutive cold events (CDCMI) based on daily minimum temperature data and a 1-month standardized precipitation evapotranspiration index (SPEI) from 1961 to 2018. Results show that the magnitude of meteorological droughts increased over the observation period, while consecutive cold events significantly decreased. CDCMI showed a significant downward trend at a rate of -0.14 per decade. Large differences were observed between 1990-2018 and 1961-1989-especially in the southern parts of the basin (around -50%). The frequency of mild and moderate concurrent meteorological droughts and consecutive cold events showed no significant upward or downward trends, but severe and extreme concurrent events showed pronounced decreasing trends at rates of -0.03 events/decade and – 0.036 events/decade, respectively. Under the same return period, high CDCMI values are present in the southeastern part of the basin, indicating that the concurrent events in this region are more serious. When CDCMI = 1.79 (extreme grade), the return period in the southeastern part of the basin (5-10 years) is much lower than that in the northwestern part of the basin (>100 years), indicating that this part is harmed to a greater extent by the concurrent extremes than elsewhere in the basin. The spatial pattern of maximum CDCMI again indicates that the southeastern part of the basin is at a high risk for concurrent events. The proposed magnitude index may be a useful tool for analysing concurrent (compound) droughts and cold events as well as their potential impacts.
Current development of temperature-related health early warning systems mainly arises from knowledge of temperature-related mortality or hospital-based morbidity. However, due to the delay in data reporting and limits in hospital capacity, these indicators cannot be used in health risk assessments timely. In this study, we examine temperature impacts on emergency ambulance and discuss the benefits of using this near real-time indicator for risk assessment and early warning. We collected ambulance dispatch data recording individual characteristics and preliminary diagnoses between 2015 and 2016 in Shenzhen, China. Distributed lag nonlinear model was used to examine the effects of high and low temperatures on ambulance dispatches during warm and cold seasons. Lag effects were also assessed to evaluate the sensitivity of ambulance dispatches in reflecting immediate health reactions. Stratified analyses by gender, age, and a wide range of diagnoses were performed to identify vulnerable subgroups. Disease-specific numbers of ambulance dispatches attributable to non-optimal temperature were calculated to determine the related medical burdens. Effects of temperature on ambulance dispatches appeared to be acute on the current day. Males, people aged 18-44 years, were more susceptible to non-optimal temperatures. Highest RR during heat exposure by far was for urinary disease, alcohol intoxication, and traumatic injury, while alcohol intoxication and cardiovascular disease were especially sensitive to cold exposure, causing the main part of health burden. The development of local health surveillance systems by utilizing ambulance dispatch data are important for temperature impact assessments and medical resource reallocation.
Although a number of epidemiological studies have examined the effects of non-optimal temperatures on mortality in Europe, evidence about the mortality risks associated with exposures to hot and cold temperatures in Bulgaria is scarce. This study provides evidence about mortality attributable to non-optimal temperatures in adults aged 65 and over in Sofia, Bulgaria, between 2000 and 2017. We quantified the relationship between the daily mean temperature and mortality in the total elderly adult population aged 65 and over, among males and females aged 65 and over, as well as individuals aged 65-84 and 85 years or older. We used a distributed lag non-linear model with a 25-day lag to fully capture the effects of both cold and hot temperatures and calculated the fractions of mortality attributable to mild and extreme hot and cold temperatures. Cold temperatures had a greater impact on mortality than hot temperatures during the studied period. Most of the temperature-attributable mortality was due to moderate cold, followed by moderate heat, extreme cold, and extreme heat. The total mortality attributable to non-optimal temperatures was greater among females compared to males and among individuals aged 85 and over compared to those aged 65 to 84. The findings of this study can serve as a foundation for future research and policy development aimed at characterizing and reducing the risks from temperature exposures among vulnerable populations in the country, climate adaptation planning and improved public health preparedness, and response to non-optimal temperatures.
Significant changes in climate variables in the last decades resulted in changes of perceived climate conditions. However, there are only few studies discussing long-lasting changes in bioclimatic conditions. Thus, the purpose of this paper is to present the temporal and spatial distribution of hazardous heat and cold stress conditions in different regions of Poland. Its focus is on long-lasting changes in such conditions in the period 1951-2018. To assess changes in hazardous thermal stress conditions, the Universal Thermal Climate Index (UTCI) was used. UTCI values at 12 UTC hour (respectively 1 pm winter time, 2 pm summer time) were calculated daily based on air temperature, relative humidity, total cloud cover and wind speed at 24 stations representing the whole area of Poland. We found that the greatest changes were observed in minimum (1.33 °C/10 years) and average (0.52 °C/10 years) UTCI values as well as in cold stress frequency (- 4.00 days per 10 years). The changes vary seasonally and regionally. The greatest increase in UTCImin and decrease in cold stress days were noted from November to March and had the highest values in north-east and east Poland, and also in the foothills of the Carpathian Mountains. The trends in maximum UTCI are much smaller and not always positive. The spatially averaged trend in UTCImax for Poland as a whole was 0.35 °C/10 years and the increase in heat stress days was 0.80 days/10 years. The highest increases in UTCImax and heat stress days were noted in eastern and south-eastern Poland.
The impact of heat waves and cold spells on mortality has become a major public health problem worldwide, especially among older adults living in low-to middle-income countries. This study aimed to investigate the effects of heat waves and cold spells under different definitions on cause-specific mortality among people aged ?65 years in São Paulo from 2006 to 2015. A quasi-Poisson generalized linear model with a distributed lag model was used to investigate the association between cause-specific mortality and extreme air temperature events. To evaluate the effects of the intensity under different durations, we considered twelve heat wave and nine cold spell definitions. Our results showed an increase in cause-specific deaths related to heat waves and cold spells under several definitions. The highest risk of death related to heat waves was identified mostly at higher temperature thresholds with longer events. We verified that men were more vulnerable to die from cerebrovascular diseases and ischemic stroke on cold spells and heat waves days than women, while women presented a higher risk of dying from ischemic heart diseases during cold spells and tended to have a higher risk of chronic obstructive pulmonary disease than men during heat waves. Identification of heat wave- and cold spell-related mortality is important for the development and promotion of public health measures.
This study aimed to estimate morbidity risk/number attributed to air extreme temperatures using time-stratified case crossover study and distributed lag non-linear model in a region of Iran during 2015-2019. A time-stratified case crossover design based on aggregated exposure data was used in this study. In order to have no overlap bias in the estimations, a fixed and disjointed window by using 1-month strata was used in the design. A conditional Poisson regression model allowing for over dispersion (Quasi-Poisson) was applied into Distributed Lag Non-linear Model (DLNM). Different approaches were applied to estimate Optimum Temperature (OT). In the model, the interaction effect between temperature and humidity was assessed to see if the impact of heat or cold on Hospital Admissions (HAs) are different between different levels of humidity. The cumulative effect of heat during 21 days was not significant and it was the cold that had significant cumulative adverse effect on all groups. While the number of HAs attributed to any ranges of heat, including medium, high, extreme, and even all values were negligible, but a large number was attributable to cold values; about 10000 HAs were attributable to all values of cold temperature, of which about 9000 were attributed to medium range and about 1000 and less than 500 were attributed to high and extreme values of cold, respectively. This study highlights the need for interventions in cold seasons by policymakers. The results inform researchers as well as policy makers to address both men and women and elderly when any plan or preventive program is developed in the area under study.
Considering that several meteorological variables can contribute to weather vulnerability, the estimation of their synergetic effects on health is particularly useful. The spatial synoptic classification (SSC) has been used in biometeorological applications to estimate the effect of the entire suite of weather conditions on human morbidity and mortality. In this study, we assessed the relationships between extremely hot and dry (dry tropical plus, DT+) and hot and moist (moist tropical plus, MT+) weather types in summer and extremely cold and dry (dry polar plus, DP+) and cold and moist (moist polar, MP+) weather types in winter and cardiovascular and respiratory hospitalizations by age and sex. Time-series quasi-Poisson regression with distributed lags was used to assess the relationship between oppressive weather types and daily hospitalizations over 14 subsequent days in the extended summer (May to August) and 28 subsequent days during the extended winter (November to March) over 24 years in 4 Swedish locations from 1991 to 2014. In summer, exposure to hot weather types appeared to reduce cardiovascular hospitalizations while increased the risk of hospitalizations for respiratory diseases, mainly related to MT+. In winter, the effect of cold weather on both cause-specific hospitalizations was small; however, MP+ was related to a delayed increase in cardiovascular hospitalizations, whilst MP+ and DP + increased the risk of hospitalizations due to respiratory diseases. This study provides useful information for the staff of hospitals and elderly care centers who can help to implement protective measures for patients and residents. Also, our results could be helpful for vulnerable people who can adopt protective measures to reduce health risks.
There is a well-established relationship between temperature and mortality, with older individuals being most at risk in high-income settings. This raises the question of the degree to which lives are being shortened by exposure to heat or cold. Years of life lost (YLL) take into account population life expectancy and age at which mortality occurs. However, YLL are rarely used as an outcome-metric in studies of temperature-related mortality. This represents an important gap in knowledge; to better comprehend potential impacts of temperature in the context of climate change and an ageing population, it is important to understand the relationship between temperature and YLL, and also whether the risks of temperature related mortality and YLL have changed over recent years. Gridded temperature data derived from observations, and mortality data were provided by the UK Met Office and the Office for National Statistics (ONS), respectively. We derived YLL for each death using sex-specific yearly life expectancy from ONS English-national lifetables. We undertook an ecological time-series regression analysis, using a distributed-lag double-threshold model, to estimate the relationship between daily mean temperature and daily YLL and mortality between 1996 and 2013 in Greater London, the West Midlands including Birmingham, and Greater Manchester. Temperature-thresholds, as determined by model best fit, were set at the 91st (for heat-effects) and 35th (for cold-effects) percentiles of the mean temperature distribution. Secondly, we analysed whether there had been any changes in heat and cold related risk of YLL and mortality over time. Heat-effects (lag 0-2 days) were greatest in London, where for each 1 °C above the heat-threshold the risk of mortality increased by 3.9% (CI 3.5%, 4.3%) and YLL increased by 3.0% (2.5%, 3.5%). Between 1996 and 2013, the proportion of total deaths and YLL attributable to heat in London were 0.50% and 0.40% respectively. Cold-effects (lag 0-27 days) were greatest in the West Midlands, where for each 1 °C below the cold-threshold, risk of mortality increased by 3.1% (2.4%, 3.7%) and YLL also increased by 3.1% (2.2%, 3.9%). The proportion of deaths and YLL attributable to cold in the West Midlands were 3.3% and 3.2% respectively. We found no evidence of decreasing susceptibility to heat and cold over time. The addition of life expectancy information into calculations of temperature-related risk and mortality burdens for English cities is novel. We demonstrate that although older individuals are at greatest risk of temperature-related mortality, heat and cold still make a significant contribution to the YLL due to premature death.
This paper describes a Cold Weather Ensemble Decision Aid (CoWEDA) that provides guidance for cold weather injury prevention, mission planning, and clothing selection. CoWEDA incorporates current science from the disciplines of physiology, meteorology, clothing, and computer modeling. The thermal performance of a cold weather ensemble is defined by endurance times, which are the time intervals from initial exposure until the safety limits are reached. These safety limits correspond to conservative temperature thresholds that provide a warning of the approaching onset of frostbite and/or hypothermia. A validated six-cylinder thermoregulatory model is used to predict human thermal responses to cold while wearing different ensembles. The performance metrics, model, and a database of clothing properties were integrated into a user-friendly software application. CoWEDA is the first tool that allows users to build their own ensembles from the clothing menu (i.e., jackets, footwear, and accessories) for each body region (i.e., head, torso, lower body, hands, feet) and view their selections in the context of physiological strain and the operational consequences. Comparison of predicted values to skin and core temperatures, measured during 17 cold exposures ranging from 0 to -40°C, indicated that the accuracy of CoWEDA prediction is acceptable, and most predictions are within measured mean ± SD. CoWEDA predicts the risk of frostbite and hypothermia and ensures that a selected clothing ensemble is appropriate for expected weather conditions and activities. CoWEDA represents a significant enhancement of required clothing insulation (IREQ, ISO 11079) and wind chill index-based guidance for cold weather safety and survival.
Cardiovascular disease is the most common cause of death globally. Examining the relationship between the extreme temperature events (e.g. heat and cold waves) and cardiovascular mortality has profound public significance. However, this evidence is scarce, particularly those from China. We collected daily data on cardiovascular mortality and meteorological conditions from 31 major Chinese cities during the maximum period of 2007-2013. A two-stage analysis was used to estimate the effects of heat and cold waves, and the potential effect modification of their characteristics (intensity, duration, and timing in season) on cardiovascular mortality. Firstly, a generalized quasi-Poisson regression combined with distributed lag nonlinear model was used to evaluate city-specific effects. Then, the meta-analysis was performed to pool effect estimates at the national scale. Overall, cardiovascular mortality risk increased by 19.03% (95%CI: 11.92%, 26.59%) during heat waves and 54.72% (95%CI: 21.20%, 97.51%) during cold waves. The effect estimates varied by the wave’s characteristics. In heat wave days, the cardiovascular mortality risks increased by 3.28% (95%CI: -0.06%, 6.73%) for every 1 degrees C increase in intensity, 2.84% (95%CI: 0.92%, 4.80%) for every 1-d more in duration and -0.07% (95%CI: -0.38%, 0.24%) for every 1-d late in the staring of heat wave; the corresponding estimates for cold wave were 1.82% (95%CI: -0.04%, 3.72%), 1.52% (95%CI: 0.60%, 2.44%) and -0.26% (95%CI: -0.67%, 0.16%). Increased susceptibility to heat and cold waves was observed among patients with ischemic heart disease, females, the elderly, and those with lower education level. And consistent vulnerable populations were found for the effects of changes in cold and heat wave’s characteristics. The findings have important implications for the development of early warning systems and plans in response to heat and cold waves, which may contribute to mitigating health threat to vulnerable populations.
Few studies have investigated the different extreme temperature effects (heat-cold) of one geographical location at the same time in Iran. This study was conducted to assess the impact of heat and cold waves on mortality in Urmia city, which has a cold and mountainous climate. Distributed Lag Non-linear Models combined with a quasi-Poisson regression were used to assess the impact of heat (HW) and cold waves (CW) on mortality in subgroups, controlled for potential confounders such as long-term trend of daily mortality, day of week effect, holidays, mean temperature, humidity, wind speed and air pollutants. The heat/cold effect was divided into two general categories A-main effect (the effect caused by temperature), B-added effect (the effect caused by persistence of extreme temperature). Results show that there was no relation between HW and respiratory and cardiovascular death, but in main effects, HW(H1) significantly increased, the risk of Non-Accidental Death (NAD) in lag 0 (Cumulative Excess Risk (CER) (NAD) = 31(CI; 4-65)). Also in added effects, HW had a significant effect on NAD (CER (H1; NAD; lag;0-2) = 31(CI; 5, 51), CER (H2; NAD; lag;0-2) = 26(CI; 6, 48)). There was no relation between CW and respiratory death and cardiovascular death, but in added effects, CW((C1)) significantly decreased, the risk of non-accidental death in initial lags (CER (C1; NAD; lag;0-2) = 19 (CI; 35, 2)). It seems that high temperatures and heat waves increase the risk of non-accidental mortality in northwest of Iran.
While there is much research that focuses on the association between cold waves and their impacts on daily mortality at the city level, few analyze the impact related to social context and demographic variables at levels lower than the municipal. The objective of this study was to determine the role of the percentage of people over age 65, income level and percentage of homes without heating in the analysis of the impact of cold waves on daily mortality between January 1, 2010 and December 31, 2013 in different districts of the municipality of Madrid. We calculated Relative Risks (RR) and Attributable Risks (RA) for each of 17 districts to determine correlations between the effect of cold waves and daily mortality due to natural causes (CIEX: A00-R99) using Generalized Linear Models (GLM) of the Poisson family (link log). The pattern of risks obtained by district was analyzed using binomial family models (link logit), considering socioeconomic and demographic variables. In terms of results, an impact of cold on mortality was detected in 9 of the 17 districts analyzed. The analysis of risk patterns revealed that the probability of detecting an impact in a district increases in a statistically significant way (p-value <0.05) with a higher percentage of homes without heating systems and a higher percentage of population over age 65. The results obtained identify the factors that should be considered in public health policies that target the district level to reduce the impact of cold waves.
We investigated whether persons with dementia (PwD) are at particular risk of mortality when exposed to extreme temperatures and whether the temperature effect depends on long-term care (LTC) need and residency. German health claims data provide information on inpatient and outpatient sectors. Data from the German Meteorological Service were merged, and measures of immediate and delayed heat, cold, and normal temperature (Heat Index, Wind Chill Temperature Index) were calculated. Cox models were applied to explore the interaction of temperature, dementia, and LTC, as well as residency. Immediate and delayed effects of heat and cold were tested as compared to normal temperatures. Models were adjusted for age, sex, comorbidities, urban/rural living, and summer/winter climate zones. The 182,384 persons aged >= 65 contributed 1,084,111 person-years and 49,040 deaths between 2004 and 2010. At normal temperatures, PwD had a 37% (p-value < 0.001) increased mortality risk compared to persons without dementia (PwoD). Immediate heat effects further increased this effect by 11% (p = 0.031); no immediate heat effect existed for PwoD. The immediate heat effect was even greater for PwD suffering from severe or extreme physical impairment and for those living in private households and nursing homes. Immediate and delayed cold effects increased mortality independent of dementia. Care level and type of residency did not modify this effect among PwD. PwD revealed an increased vulnerability to immediate heat effects. Cold waves were risk factors for both groups. LTC need appeared to be an important intervening factor.
OBJECTIVES: to evaluate the effect of air pollution (ozone – O3 and particulate matter <=10 ?m and <=2.5 ?m - PM10 and PM2.5) on the severity of Raynaud's phenomenon (RP) secondary to systemic sclerosis (SSc). DESIGN: cross-sectional, observational, and single centre study. SETTING AND PARTICIPANTS: all consecutive SSc patients residing in Lombardy (Northern Italy) were enrolled. PM10, PM2.5, and O3 concentrations were calculated for each patient at municipality resolution in the week before the evaluation. Similar considerations were made for meteorological variables (temperature and humidity). MAIN OUTCOME MEASURES: patients were asked to assess RP severity during the week before the evaluation according to a visual analogue scale (VAS). Ordinal logistic regression models were fitted to evaluate the short-term effect of temperature and air pollution with respect to RP. A univariate linear regression model was created to consider the association between temperature and pollutants. RESULTS: in this study, 87 SSc patients were enrolled. Temperature was confirmed to strongly influence RP severity. PM10 and PM.5 were found to significantly worsen RP severity for the first four days before the evaluation, including the day of the visit, and as mean up to six days before the evaluation. O3 seemed to exert a protective effect on RP severity that was significant for the first four days before the evaluation, including the day of the visit, and as mean up to seven days before the evaluation. CONCLUSIONS: since the overwhelming effect of temperature on RP, final conclusions about the exact contribution of pollutants on RP severity cannot be drawn because of the strong inter-correlation between air pollution and temperature.
Consideration of the implications of solar UV exposure on public health during extreme temperature events is important due to their increasing frequency as a result of climate change. In this paper public health impacts of solar UV exposure, both positive and negative, during extreme hot and cold weather in England in 2018 were assessed by analysing environmental variations in UV and temperature. Consideration was given to people’s likely behaviour, the current alert system and public health advice. During a period of severe cold weather in February-March 2018 UV daily doses were around 25-50% lower than the long-term average (1991-2017); however, this would not impact on sunburn risk or the benefit of vitamin D production. In spring 2018 unseasonably high temperatures coincided with high UV daily doses (40-75% above long-term average) on significant days: the London Marathon (22 April) and UK May Day Bank Holiday weekend, which includes a public holiday on the Monday (5-7 May). People were likely to have intermittent excess solar UV exposure on unacclimatised skin, causing sunburn and potentially increasing the risk of skin cancers. No alerts were raised for these events since they occurred outside the alerting period. During a heat-wave in summer 2018 the environmental availability of UV was high-on average of 25% above the long-term average. The public health implications are complex and highly dependent on behaviour and sociodemographic variables such as skin colour. For all three periods Pearson’s correlation analysis showed a statistically significant (p<0.05) positive correlation between maximum daily temperature and erythema-effective UV daily dose. Public health advice may be improved by taking account of both temperature and UV and their implications for behaviour. A health impact-based alert system would be of benefit throughout the year, particularly in spring and summer.
BACKGROUND: Often quoted as “heaven on earth,” Kashmir forms one of the two divisions of the Union territory of Jammu and Kashmir. A high-altitude region with abundant precipitation and snowfall, the people of Kashmir experience peculiar dermatoses not commonly seen in the majorly tropical subcontinent of India. In this study, we focussed on cold dermatoses as a comprehensive cluster and attempted to study them as a group. AIMS: To determine the prevalence of cold dermatoses in Kashmir valley and study their epidemiological characteristics. METHODS: This observational, cross-sectional community-based study was conducted on native Kashmiri population in three districts of the valley, exclusively during the winter season of the year 2016-17 and 2017-18. The data were tabulated and analyzed with Chi-square test for discrete variables and t-test for continuous variables, using OpenEpi. A P value of less than 0.05 was taken as significant. RESULTS: The study included a total of 1200 cases with 602 males and 598 females. Perniosis was most commonly encountered dermatoses in our study with a prevalence of 12.2%. Frostbite had a prevalence of 0.83%. Raynaud’s phenomenon and asteatotic eczema were seen in 1.5% and 1.67% of the population, respectively. Cold panniculitis, cold urticaria, and livedo reticularis were each seen in 0.08% of the population. CONCLUSIONS: Cold dermatoses form an important source of morbidity among the native population of Kashmir. These can be easily prevented by ensuring adequate protection against cold. Creating awareness regarding these disorders and probable association with connective tissue disorders is also imperative.
We have examined the heat and cold-related mortality risk subject to cold and heat extremes by using a generalized additive model (GAM) regression technique to quantify the effect of the stimulus of mortality in the presence of covariate data for 2007-2014 in Nicosia, Cyprus. The use of the GAM technique with multiple linear regression allowed for the continuous covariates of temperature and diurnal temperature range (DTR) to be modeled as smooth functions and the lag period was considered to relate mortality to lagged values of temperature. Our findings indicate that the previous three days’ temperatures were strongly predictive of mortality. The mortality risk decreased as the minimum temperature (T-min) increased from the coldest days to a certain threshold temperature about 20-21 degrees C (different for each age group and gender), above which the mortality risk increased as T-min increased. The investigated fixed factors analysis showed an insignificant association of gender-mortality, whereas the age-mortality association showed that the population over 80 was more vulnerable to temperature variations. It was recommended that the minimum mortality temperature is calculated using the minimum daily temperatures because it has a stronger correlation to the probability for risk of mortality. It is still undetermined as to what degree a change in existing climatic conditions will increase the environmental stress to humans as the population is acclimatized to different climates with different threshold temperatures and minimum mortality temperatures.
BACKGROUND: Estimating the effects of climate change on human health can help health policy makers plan for the future. In Iran, there are few studies, about investigating the effects of climate change on mortality. This study aimed to project the effect of low (cold) and high (heat) temperature on mortality in a dry region of Iran, Kerman. METHODS: Mortality attributed to temperature was projected by estimating the temperature-mortality relation for the observed data, projection of future temperatures by the statistical downscaling model (SDSM), and quantifying the attributable fraction by applying the observed temperature-mortality relation on the projected temperature. Climate change projection was done by three climate scenarios base on Representative Concentration Pathways (RCP2.6, RCP4.5 and RCP8.5). Adaptation was considered by using different minimum mortality temperatures (MMT) and risk reduction approaches. The current decade (2010-19) was considered as the reference period. RESULTS: All three climate change scenarios, showed that the mean of temperature will rise about 1 °C, by 2050 in Kerman. The number of deaths attributed to heat were obviously higher than cold in all periods. Assuming no adaptation, over 3700 deaths attributed to temperature will happen in each decade (2020s, 2030s and 2040s) in the future, in which over 3000 deaths will be due to heat and over 450 due to cold. In the predictions, as Minimum Mortality Temperature (MMT) went up, the contribution of heat to mortality slightly decreased, and cold temperature played a more important role. By considering the risk reduction due to adaptation, the contribution of heat in mortality slightly and insignificantly decreased. CONCLUSION: The results showed that although low temperatures will contribute to temperature-related mortality in the future, but heat will be a stronger risk factor for mortality, especially if adaptation is low.
We aimed to investigate whether month of birth is associated with blood pressure (BP) and prevalent hypertension in adults from a region with frost-free days of <150 days and average temperatures - 13°C in winter, Xinjiang, China. We analyzed data for 6158 subjects from several surveys. We divided participants into April to August (n = 2624) and September to March (n = 3534) groups, based on length of maternal exposure to cold months, and analyzed BP, prevalent hypertension, and related factors. Diastolic BP in total subjects and systolic and diastolic BP in male subjects born between April and August were significantly higher than in those born between September and March. In sensitivity analysis, untreated males born between April and August showed significantly higher systolic and diastolic BP than did their counterparts. Subjects born between April and August showed significantly higher prevalence of hypertension (31.3% vs 27.8%, P = .003), and isolated systolic (23.3% vs 20.8%, P = .018) and diastolic hypertension (24.5% vs 21.4%, P = .004), than those born between September and March, which is similar for men. Birth between April and August showed 1.68 (95% CI: 1.06-2.67, P = .027)-fold increased odds for the prevalence of hypertension, independent of gender, age, body mass index, waist circumference, cigarette consumption, alcohol intake, and family history, compared with their counterparts. In conclusion, maternal exposure to cold spells during pregnancy may be associated with the increased risk of hypertension in offspring later in life, particularly among males, suggesting the involvement of maternal cold exposure during pregnancy in offspring hypertension development.
More than four hundred million people suffer from respiratory diseases each year. Respiratory diseases are associated with a large disease burden. Heatwaves and cold spells, the two most common extreme weather events, have been shown to have crucial negative effects on the prevalence of respiratory diseases. However, impacts of extreme weather on the prevalence of respiratory diseases has been largely overlooked in western China, where more intense and frequent extreme temperature events have been occurring over the past decades. This research gap will obtain an attribution bias in the effects of extreme weather events on the prevalence of respiratory diseases. Therefore, in this study, we analyzed the impact of heatwaves and cold spells on the morbidity of respiratory diseases using a distributed lag nonlinear model with daily disease cases from 2013 to 2016 in Lanzhou, one of the largest cities in western China. A reverse U-shaped relationship depicted the relationship between temperature and the morbidity of respiratory diseases. The highest relative risk was found at 2.6 degrees C by 1.15 (95% confidence interval: 1.09-1.21). Furthermore, we found a significant decrease in the relative risk for heatwaves and a significant increase in the relative risk of cold spells when the temperature exceeded the corresponding threshold by 1 degrees C. Heatwaves and cold spells play harvest effects on the morbidity of respiratory diseases. Our study suggest that the relative risk of respiratory diseases will increase as the climate warms in the future, and thus a preventive system is needed for individuals and medical policy-makers.
The spatial synoptic classification (SSC) is a holistic categorical assessment of the daily weather conditions at specific locations; it is a useful tool for assessing weather effects on health. In this study, we assessed (a) the effect of hot weather types and the duration of heat events on cardiovascular and respiratory mortality in summer and (b) the effect of cold weather types and the duration of cold events on cardiovascular and respiratory mortality in winter. A time-stratified case-crossover design combined with a distributed lag nonlinear model was carried out to investigate the association of weather types with cause-specific mortality in two southern (Skåne and Stockholm) and two northern (Jämtland and Västerbotten) locations in Sweden. During summer, in the southern locations, the Moist Tropical (MT) and Dry Tropical (DT) weather types increased cardiovascular and respiratory mortality at shorter lags; both hot weather types substantially increased respiratory mortality mainly in Skåne. The impact of heat events on mortality by cardiovascular and respiratory diseases was more important in the southern than in the northern locations at lag 0. The cumulative effect of MT, DT and heat events lagged over 14 days was particularly high for respiratory mortality in all locations except in Jämtland, though these did not show a clear effect on cardiovascular mortality. During winter, the dry polar and moist polar weather types and cold events showed a negligible effect on cardiovascular and respiratory mortality. This study provides valuable information about the relationship between hot oppressive weather types with cause-specific mortality; however, the cold weather types may not capture sufficiently effects on cause-specific mortality in this sub-Arctic region.
Purpose The purpose of this paper is to examine the seasonal performance, occupants’ comfort and cold stress in cross-laminated timber school buildings located in the USA (Northeast region). Design/methodology/approach The Fall survey was done from October-November 2017. In the Winter, it was considered from December 2017-February 2018. The study measured environmental parameters in the chosen spaces. The research applied the wet-bulb globe temperature (WBGT) model to determine the indexes in various seasons. Findings In the Fall, the average inside temperature was 21.2 degrees C, the average RH was 50.7 per cent, and the mean dew-point was 9.3 degrees C. The mean inside temperature was 20.5 degrees C in the Winter while the mean RH was 23.9 per cent and the average dew-point was -1.9 degrees C. The overall mean inside temperatures in both seasons were within the ASHRAE comfort temperature limits for cold seasons. During the surveys, higher average values of temperature, RH and dew-point were measured in the offices than the other spaces. Practical implications The research showed people might be subject to lower temperatures in the hall than the other spaces. Some design parameters and occupation hours may contribute to the lower temperatures reported in the hall than the different spaces. Originality/value The study proposes the WBGT of 16.0 degrees C and 13.7 degrees C as the stress indexes in the Fall and Winter seasons correspondingly. Last, the research suggests a WBGT of 14.9 degrees C as the overall mean stress index within the spaces considered in this study.
The present study explores the spatial and temporal pattern of cold wave related mortalities over India. The data for this study has been obtained from the annual reports pertaining to ‘Disastrous Weather Events’ published by India Meteorological Department, Pune for 37-years (1978-2014). The analysis reveals that a total of 8520 mortalities have been caused by 606 cold wave events, with an average of 230 mortalities per year. Only two states i.e. Bihar (44%) and Uttar Pradesh (31%) account for approximately 75% of total cold waves mortalities, while eleven states namely, Arunachal Pradesh, Assam, Goa, Karnataka, Kerala, Manipur, Mizoram, Nagaland, Sikkim, Tamil Nadu and Tripura have never experienced cold wave events and mortalities. Interestingly, each cold wave event has caused approximately 43 mortalities alone in Bihar state. Furthermore, mortality (standardized by population) and density rates (standardized by area) in India have been observed to be 0.24 and 2.65, respectively. In temporal terms, cold wave events and mortalities have shown large interannual variations without any significant increasing or decreasing trend. Most of the cold wave events and mortalities have been observed in January and December months. Males have been found to be more severely affected by the cold waves than females and children. Overall, the results of this research may provide an understanding to develop effective disaster management guidelines for temperature extremes safety and preparedness.
Introduction: Hypothermia at admission in trauma patients has been significantly associated with worse outcomes and increased blood usage. Previous studies have found variably significant associations between ambient temperatures and incidence of hypothermia in trauma patients. Methods: The trauma quality improvement registry was queried for data on trauma patients admitted direct from the scene over a 5-year period. This database was matched to daily weather data taken from the nearest National Oceanic and Atmospheric Administration land-based climate monitoring center, and further combined with blood usage data from the laboratory information system. Results: Multivariate logistic regression models predicted significant associations between ambient temperature and patient admission temperature for severely injured patients. No significant direct associations were predicted between ambient temperature and in-hospital mortality or blood usage. Models predicted a significant association between decreased admission temperature and increased likelihood of both blood transfusion and mortality for a severely injured subgroup. Conclusions: Ambient temperature is a significant contributor to the rate of admission hypothermia in trauma patients. Most of the variability in admission temperatures for severely injured trauma patients remains unaccounted for by models using standard markers of anatomic and physiologic severity. Decreasing admission temperature is significantly associated with increased mortality and likelihood of blood transfusion for severely injured patients.
