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Short-term effect of heat waves on hospital admissions in Madrid: Analysis by gender and comparision with previous findings
... A series of factors can modify the effects of heat on human health, such as sex, the division of labor and exposure to extreme heat and age [17,18]. The role of sex as a risk factor remains unclear, and the assessment is limited [17]. ...
... A series of factors can modify the effects of heat on human health, such as sex, the division of labor and exposure to extreme heat and age [17,18]. The role of sex as a risk factor remains unclear, and the assessment is limited [17]. Hence, achieving a better understanding of the heterogeneity of the sexes in different age groups is essential to identify vulnerable populations exposed to heat. ...
... In the age group of 15-64 years, the effect of extreme heat is stronger among men than women in Suzhou and Yancheng. This might be due to outdoor activities and the occupational division of labor [17]. ...
In the context of climate change, heat waves are a serious hazard having significant impacts on human health, especially vulnerable populations. Many studies have researched the association between extreme heat and mortality. In the context of urban planning, many studies have explored the cooling effect of green roofs, parks, urban forests and urban gardens. Nevertheless, few studies have analyzed the effect mechanism of specific ecosystem services (ESs) as mitigation measures to heat waves. This study aimed to determine the relationship among ESs, heat waves and the heat-related mortality risk of different groups by diseases, age and sex. The research was conducted in three cities in Jiangsu Province, including Nanjing, Suzhou and Yancheng. We quantified five ecosystem services, i.e., water supply service, carbon sequestration service, cooling service, biodiversity and cultural service. Based on the previous studies, we took the frequency of heat waves into account, extending the concept of the Heat Wave Magnitude Index (HWMI). A distributed lag nonlinear model (DLNM) was applied to estimate the effect of extreme heat on mortality. Then, the study used the process analysis method to explore the relationship among ESs, heat waves and heat-related mortality risks. The results indicated that (i) water supply service, carbon sequestration service, cooling service and biodiversity can reduce heat-related mortality while cultural service increases; (ii) the effects of carbon sequestration service and cultural service are stronger than other ESs; (iii) the effects of ESs on cardiorespiratory disease, stroke and chronic obstructive pulmonary disease (COPD) mortality risks are higher than others; and (iv) women and elderly heat-related mortality risks are more affected by the ESs. This study can provide a theoretical support for policy makers to mitigate heatwave events, thus limiting heat-related mortality.
... On the other hand, there are factors that should result in a decrease in the impact of heat in the future. These include, for example, the existence of an active adaptation process within the population (both autonomously by individuals and families, and by the authorities and institutions), due to multiple factors from the so called "culture of heat" (Bobb et al. 2014), to the implementation of prevention plans (Schifano et al. 2012), improvements in health services (van Loenhout et al. 2016), and improvements in socio-economic circumstances and infrastructure of homes, as well as an increase in the number of air conditioning units (Díaz et al. 2018b), among others. ...
... For example, several studies conducted in Spain, found greater MMT values in men when analyzing cardiovascular mortality (Achebak et al., 2019) and mortality from circulatory and respiratory causes (Achebak et al., 2018). On the other hand, some studies carried out in Madrid have shown that women present greater risk, both in terms of death as well as hospital admissions due to natural causes, during a heat wave (Díaz et al., 2018;García-Herrera et al., 2005). Also, in Barcelona that women showed a higher relative risk of mortality compared to men with summer temperature extremes (Ingole et al., 2020). ...
In Spain the average temperature has increased by 1.7°C since pre-industrial times. There has been an increase in heat waves both in terms of frequency and intensity, with a clear impact in terms of population health. The effect of heat waves on daily mortality presents important territorial differences. Gender also affects these impacts, as a determinant that conditions social inequalities in health. There is evidence that women may be more susceptible to extreme heat than men, although there are relatively few studies that analyze differences in the vulnerability and adaptation to heat by sex. This could be related to physiological causes. On the other hand, one of the indicators used to measure vulnerability to heat in a population and its adaptation is the minimum mortality temperature (MMT) and its temporal evolution.
The aim of this study was to analyze the values of MMT in men and women and its temporal evolution during the 1983-2018 period in Spain’s provinces. An ecological, longitudinal retrospective study was carried out of time series data, based on maximum daily temperature and daily mortality data corresponding to the study period. Using cubic and quadratic fits between daily mortality rates and the temperature, the minimum values of these functions were determined, which allowed for determining MMT values. Furthermore, we used an improved methodology that provided for the estimation of missing MMT values when polynomial fits were inexistent. This analysis was carried out for each year. Later, based on the annual values of MMT, a linear fit was carried out to determine the rate of evolution of MMT for men and for women at the province level.
Average MMT for all of Spain’s provinces was 29.4 °C in the case of men and 28.7 °C in the case of women. The MMT for men was greater than that of women in 86 percent of the total provinces analyzed, which indicates greater vulnerability among women. In terms of the rate of variation in MMT during the period analyzed, that of men was 0.39 °C/decade, compared to 0.53 °C/decade for women, indicating greater adaptation to heat among women, compared to men. The differences found between men and women were statistically significant. At the province level, the results show great heterogeneity.
Studies carried out at the local level are needed to provide knowledge about those factors that can explain these differences at the province level, and to allow for incorporating a gender perspective in the implementation of measures for adaptation to high temperatures
... On the other hand, there are factors that should result in a decrease in the impact of heat in the future. These include, for example, the existence of an active adaptation process within the population (both autonomously by individuals and families, and by the authorities and institutions), due to multiple factors from the so called "culture of heat" (Bobb et al. 2014), to the implementation of prevention plans (Schifano et al. 2012), improvements in health services (van Loenhout et al. 2016), and improvements in socio-economic circumstances and infrastructure of homes, as well as an increase in the number of air conditioning units (Díaz et al. 2018b), among others. ...
... This project followed previous works that tried to bring light into the phenomenon. Feminisation of energy poverty has been approached from different perspectives and deepened into housing habitability [51], the sexual division of labour, reproductive work and gender roles [52], thermal perception and differences in health issues between sexes [53,54], within gender mainstreaming as an approach to policy-making [55]. FemenMAD project searched to add fieldwork combining interviews with monitorisation of all of these existent perspectives. ...
The analysis of energy poverty at the national and regional level, as well as its methodologies and definitions, is a widely discussed issue. With a view to intervention and prioritisation, it is essential to have a description of the problem at smaller scales, allowing the identification of the most vulnerable areas and their description. This will favour the application of public policies adapted to the needs of each area detected. This research shows different approaches and possible analyses to advance in this direction in the Spanish context. The conceptual bases of these methodologies are described to allow possible transpositions to other contexts that share the same limitations in their statistical body. Finally, the potentialities, utilities and limitations of these methodologies are described and analysed. One of the most relevant conclusions is that the analysis of energy poverty on a local scale is a crucial element in the advancement of this area of knowledge, given that the inequalities present in our territories make it necessary to identify tailor-made solutions to fight against energy poverty in an efficient and resource-optimised manner.
... It's worth adding, physiological changes in the organisms of the elderly, and the more difficult financial situations of this group, often lead to insufficient provision of adequate thermal conditions in the apartment, which is confirmed by own research and other studies [158]. Research emphasizes that the elderly population is more exposed to extreme temperatures in both winter and summer [159,160]. ...
The household sector contributes significantly to a country’s energy consumption. Energy carrier expenses are the highest expenditures in Polish household budgets. Households run by individuals aged 60 and older are heavily burdened with energy expenditures. The scientific aim of the research is to present and assess housing conditions, with particular emphasis on energy poverty in households run by individuals aged 60 and older. Multivariate statistical analyses were used to conduct the research objectives (cluster methods, variance methods, regression methods). This paper identifies a new index—one that has been applied to the situation in Poland. Households that consist of elderly people are strongly diversified in terms of housing conditions (including energy conditions). There are concerns that some households are not able to access energy services that are required to satisfy basic human needs, particularly individuals with low levels of education, living on social benefits, with low disposable incomes, or living in the countryside. Households represented by men aged 60 and older have better energy supply than households run by women. The older the individual representing the household, the greater the likelihood that his/her energy service needs are not met.
... Risks associated with a different physiological response to high temperatures are also relevant between the sexes (Díaz et al. 2018;López-Bueno et al. 2019). Within the framework of the FEMENMAD project, the differences in terms of mortality and emergency hospital admissions were also analyzed. ...
Recent research has addressed the special relationship between energy poverty and women. Despite that not many studies are yet available, results show that there might be strong gender inequalities connected with household’s energy deprivation. Furthermore, differentiated health impacts have been detected between men and women, putting women into a more vulnerable position. In this sense, the so-called feminization of energy poverty is urging a revision of the existing studies from a gender perspective to foster its inclusion within energy poverty alleviation policies. The present study explores the links between summer energy poverty and gender in the city of Madrid. Summer energy poverty is considered another variety of energy deprivation particularly relevant within mid- and low-latitude countries, in which energy consumption for cooling is heavily increasing. It also seems to be particularly relevant in cities in which the urban heat island introduces relevant variations in the microclimatic conditions that might increase the housing-cooling demand. Following the methodology developed in previous studies, the risk of suffering from summer energy poverty is, in this paper, explored considering the household’s gender composition. The geospatial distribution of their vulnerability is compared with other indicators related to their exposure to high temperatures: the housing energy efficiency and the cooling degree hours. The evaluation at the sub-municipal scale is carried out among the different subgroups in which a woman is the main breadwinner: single women with children and single women over 65 years old. Their situation is also compared to those households in which a man is the main breadwinner. The analysis of the selected variables is conducted using a hotspot analysis, which evaluates the autocorrelation of each variable according to its spatial distribution. Results show that women living alone and above 65 years old seem to be under the highest risk. They concentrate in areas with low energy-efficient housing stock and strong urban heat island intensities. On a general basis, the income gap between women and men makes it advisable to address energy poverty with a gender perspective.
... In the words of Wilkinson (2004): "Women, however, had a larger winter:non-winter ratio than men for reasons other than their greater age, previous health status, social isolation, or socioeconomic position". It has been demonstrated that the population over 65 is more vulnerable to extreme summer and winter temperatures, and epidemiological evidence has also highlighted differences in this group by gender during heatwave events [40]. ...
Almost 23% of households in the city of Madrid are at risk of energy poverty according to the Technical Study on Energy Poverty in Madrid. Women are the main breadwinners in over half these households, and may either be pensioners or heads of single-parent families, highlighting the existence of gender inequalities in relation to energy poverty. Recent studies have noted that women are more sensitive to extreme temperatures, which may place women suffering energy poverty at a greater risk. These worrying data point to the urgent need to analyse the incidence of energy poverty from a gender perspective.
This study focuses on the feminisation of energy poverty in the city of Madrid using various statistical databases and Geographic Information Systems to perform an exploratory analysis on its distribution. The aim is to characterise women’s different deprivation conditions within the city, and the geographical distribution of this unequal access to energy. This research is expected to contribute to an overhaul of public policies for housing, energy and public health in Madrid.
... Excessive nocturnal heat negatively influences not only human health -including increasing mortality rates due to heat stress [90,91] and more frequent insomnia [92]-but also impacts labor productivity [93]. Many analyses have highlighted the vulnerability of Madrid's population to extreme temperatures; likewise, both mortality and morbidity are closely related to the worsening of air quality in the city [94][95][96]. Besides, research has shown a distinctive spatial pattern of mortality: the city center districts are more vulnerable because of the predominance of aged people, and the antiquity and lower quality of the buildings [97]. Our research agrees with this pattern of vulnerability, since those districts experience an enhanced nocturnal UHI and the worst air quality during heat waves. ...
Heat waves pose additional risks to urban spaces because of the additional heat provided by urban heat islands (UHIs) as well as poorer air quality. Our study focuses on the analysis of UHIs, human thermal comfort, and air quality for the city of Madrid, Spain during heat waves. Heat wave periods are defined using the long-term records from the urban station Madrid-Retiro. Two types of UHI were studied: the canopy layer UHI (CLUHI) was evaluated using air temperature time-series from five meteorological stations; the surface UHI (SUHI) was derived from land surface temperature (LST) images from MODIS (Moderate Resolution Imaging Spectroradiometer) products. To assess human thermal comfort, the Physiological Equivalent Temperature (PET) index was applied. Air quality was analyzed from the records of two air quality networks. More frequent and longer heat waves have been observed since 1980; the nocturnal CLUHI and both the diurnal and nocturnal SUHI experience an intensification, which have led to an increasing number of tropical nights. Conversely, thermal stress is extreme by day in the city due to the lack of cooling by winds. Finally, air quality during heat waves deteriorates because of the higher than normal amount of particles arriving from Northern Africa
... This geographical heterogeneity, in terms of temperature as well as mortality, is present in studies conducted both at a multicountry Guo et al., 2018;Martinez et al., 2016) and at single-country level (Oleson et al., 2018;Weinberger et al., 2017). While it is clear that studies on a global scale can mark out adaptive strategies to be followed at a macro level, real adaptation should nonetheless be carried out at a local level (López-Bueno et al., 2019;Díaz et al., 2018). To this end, it is essential to have studies which take into account these regional differences in the various parameters that will define the impact of heat waves on mortality over different time horizons, not only with respect to determination of threshold temperatures and the impact of heat on mortality, which should factor in geographical factors and local socio-economic and demographic characteristics (Montero et al., 2012;Díaz et al., 2015b;Carmona et al., 2016;Oleson et al., 2018), but also with respect to the temperatureprojection models which have to be constructed with greater accuracy, both temporal and geographical (Amblar et al., 2017). ...
Background: In recent years, a number of studies have been conducted with the aim of analysing the impact that high temperatures will have on mortality over different time horizons under different climate scenarios. Very few of these studies take into account the fact that the threshold temperature used to define a heat wave will vary over time, and there are practically none which calculate this threshold temperature for each geographical area on the assumption that there will be variations at a country level.
Objective: To analyse the impact that high temperatures will have on mortality across the periods 2021-2050 and 2051-2100 under a high-emission climate scenario (RCP8.5), in a case: (a) where adaptation processes are not taken into account; and (b) where complete adaptation processes are taken into account.
Material and methods: Based on heat-wave definition temperature (Tthreshold) values previously calculated for the reference period, 2000-2009, for each Spanish provincial capital, and their impact on daily mortality as measured by population attributable risk (PAR), the impact of high temperatures on mortality will be calculated for the above-mentioned future periods. Two hypotheses will be considered, namely: (a) that Tthreshold does not vary over time (scenario without adaptation to heat); and, (b) that Tthreshold does vary over time, with the percentile to which said Tthreshold corresponds being assumed to remain constant (complete adaptation to heat). The temperature data were sourced from projections generated by Coupled Model Intercomparison Project (CMIP5) climate models adapted to each region’s local characteristics by the State Meteorological Agency (Agencia Estatal de Meteorología/AEMET). Population-growth projections were obtained from the National Statistics Institute (Instituto Nacional de Estadística/INE). In addition, an economic estimate of the resulting impact will be drawn up.
Results: The mean value of maximum daily temperatures will rise, in relation to those of the reference period (2000-2009), by 1.6⁰C across the period 2021-2050 and by 3.3⁰C across the period 2051-2100. In a case where there is no heat-adaptation process, overall annual mortality attributable to high temperatures in Spain would amount to 1,414 deaths/year (95% CI: 1,089 – 1,771) in the period 2021-2050, rising to 12,896 deaths/year (95% CI: 9,852 – 15,976) in the period 2051-2100. In a case where there is a heat-adaptation process, annual mortality would be 651 deaths/year (95% CI: 500 - 807) in the period 2021-2050, and 931 deaths per year (95% CI: 770 - 1081) in the period 2051-2100. These results display a high degree of heterogeneity. The savings between a situation that does envisage and one that does not envisage an adaptive process is €49,100 million/year over the 2051-2100 time horizon.
Conclusion: A non-linear increase in maximum daily temperatures was observed, which varies widely from some regions to others, with an increase in mean values for Spain as a whole that is not linear over time. The high degree of heterogeneity found in heat-related mortality by region and the great differences observed on considering an adaptive versus a non-adaptive process render it necessary for adaptation plans to be implemented at a regional level.
Background
Temperature-related circulatory mortality has gained consistent public health importance worldwide due to changes in inter-annual average temperatures and the increased frequency of extreme events over time. This study investigates the association between temperature and circulatory deaths in one of the highest population densities in the world (Malta) with a Mediterranean climate.
Methods
Daily deaths relating to circulatory mortality (32,847 deaths) were obtained from January 1992 to December 2017. A distributed lag non-linear model (DLNM) with a Poisson distribution was utilized to estimate effects of ambient temperatures and heatwaves or cold spells (2–4 consecutive days). Effects were also explored for the specific cause of death, different age groups, gender and time periods.
Results
The study observed a U-shaped cumulative exposure–response curve with a greater mortality risk due to cooler temperatures (8–15°C) after adjusting for harvesting effects (0–27 days). Colder temperatures (<8.9°C) were strongly related to both ischemic heart disease (IHD) (RR, 1.85, 95% CI, 1.24–2.77) and cerebrovascular disease (RR, 3.80,95% CI, 1.57–9.17). While heat effects were short-term (0–5 lag days), the cold effects were long-term (0–27 days) and consistent across different lag days. Cooler temperatures (8.99–12.6°C) were also related to IHD mortality in males (RR, 1.94, 95% CI, 1.05–3.59) and females (RR, 1.95, 95% CI, 1.2–3.59) and cerebrovascular mortality in females (RR, 8.32, 95% CI, 2.58–26.80). Elderly females (over 65 years) had a higher risk of death relating to IHD (RR, 1.33, 95% CI, 1.19–3.18) and cerebrovascular diseases (RR, 8.84, 95% CI, 2.64–29.61). Interestingly, colder temperatures (<8.9°C) were highly related to cerebrovascular deaths in the earliest time period (1992–2000) and IHD deaths in the most recent time period (2000–2017). While the effect of heatwaves was unclear across the time periods, there was some visible cold-spell effects for cerebrovascular mortality (RR, 1.03, 95% CI, 1.01–1.06).
Conclusion
This study used a long time series of mortality data from a high population density area to explore the impact of ambient temperature and extreme events on circulatory deaths. The results of the study will help to improve preventive and adaptive strategies to mitigate climatic health impacts.
Rapid urbanization, increasing, and aging population combined with rising temperatures and extreme weather events present severe worldwide challenges for the near future. Spain is not an exception, characterized by one of the highest life expectancies in Europe and a very high urban density. Moreover, its diverse climate, ranging from arid to wet, hot, and cold regions, is broadly affected by heatwaves during the summertime. In addition, the Spanish built environment presents some overheating challenges. Therefore, although there is ongoing research on heat-related mortality in Spain, there is a strong need for a systematic overview. This study aims to overview the current state of heat mortality trends from the last 25 years and describe current population trends, climate, heatwaves, and the Spanish built environment to provide a context-specific overview. In addition, this chapter presents the most relevant outcomes in research using the Scopus database, and 27 published papers on heat-related mortality are reviewed and discussed. Moreover, data of heat-specific deaths will be presented for the first time, concluding that 62% of the deceased were over 65 years old, and 58% were men. Finally, the already implemented mitigation strategies in several Spanish cities are discussed. To conclude, we found a strong link between overheating and heatwaves in the number of deaths but a decline in the number of heat-related deaths reported in research. A standardized research methodology is needed to adequately classify and determine heat-specific deaths with indicators such as location, population size, and threshold temperature. In addition, although heat mitigation strategies have been heterogeneously implemented in several Spanish cities, there is scant monitoring to quantify their effectiveness. Future research should address these knowledge gaps to find the most suitable strategies for every climate and urban condition.KeywordsUrban overheatingHeatwavesSpainHeat-related deathsCo-morbidityMitigation strategies
The main objective of the work under study is to find means and tools to achieve the reduction of energy poverty in Spain: creation of a social bonus of services that allows politicians to make decisions for it. This energy bond or “social service bonus” includes energy costs: electricity and gas, telecommunications (Internet), as well as other supplies (water and discharge). The first thing that arises is the reduction of supply costs by optimizing the installation and contracting systems. We start from the data provided from the previous study on energy demand and the corresponding energy improvement and sustainability measures, in a public building of social housing in C / La María, in Seville. This study shows that it is possible to achieve energy self-sufficiency and improved comfort in an efficient and cost-effective way in the short term. Next, the reduction of costs by modifying the contracting systems and the study of the social bonuses offered by the different companies in the different supplies are studied. With the data obtained, it is proposed to create a “social bonus of services” where the total cost of them could be reduced from 80 to 90% of the current payment. Finally, it is proposed that the social bonus of services can have the same treatment as the rent, with a system of subsidy or bonus of the same depending on the family and income parameters of the tenants.
Energy poverty is a multidimensional issue, with root causes that vary from country to country, and therefore requires each country to develop its own strategies and policies. In Finland, the incidence of wintertime energy poverty is relatively low according to European indicators, and hence largely unrecognized as a social issue. These current low levels of energy poverty are largely due to generally energy-efficient housing, extensive district heating infrastructure, and social security measures to support citizens’ well-being; however, energy poverty still exists within the most vulnerable groups. In addition, there is growing evidence of increasing levels of summertime occupant discomfort from high indoor temperatures due to a warming climate and housing stock that is designed for a cool rather than a hot climate. In the absence of passive cooling measures, this might lead to higher energy demands for active cooling in homes, and the subsequent risk of energy poverty in households unable to both install cooling measures and/or afford the related increases in cooling expenses. This chapter brings to the foreground overlooked issues in winter and summer energy poverty in Finland, providing a brief overview of the situation, and describing the measures employed to reduce winter energy poverty to current low levels. The potential building cooling energy increase in a warming climate, and the lack of research data to properly understand this phenomenon in Finland is then discussed. Context-specific considerations are made with regards to the need for inclusion of Nordic-region specific energy poverty approaches. Finally, this chapter provides a starting point for the reflection on what strategies should be implemented to effectively mitigate energy poverty now and in the future.
Energy poverty is a socio-environmental challenge of urban significance that has been seldom explored quantitatively at the city scale as most indicator-based analyses are conducted at national or regional levels. Acknowledging this gap in the energy poverty literature, this chapter leverages a unique set of quantitative data sources available for Barcelona to estimate the incidence of energy poverty in the grain of the city. Indicators based on the Spanish Survey on Income and Living Conditions (SILC) show that 11% of Barcelona’s 1.5 million population were in energy poverty as of 2016, with higher rates in disadvantaged districts and vulnerable sub populations. The analysis applies a novel approach that interprets available indicators as complementary metrics capable of capturing the different degrees and experiences of domestic energy deprivation. It also highlights three insufficiently explored aspects of energy poverty, namely, the issue of electricity-based domestic heat, the question of arrears, indebtedness and disconnection from basic utility services, and the link with housing insecurity. These elements are relevant for other urban areas of post-crisis and austerity in the Mediterranean EU, with Barcelona being introduced as a pioneer city for its commitment to tackle domestic energy deprivation in this context.
The Mediterranean Basin is undergoing a warming trend with longer and warmer summers, an increase in the frequency and the severity of heat waves, changes in precipitation patterns and a reduction in rainfall amounts. In this unique populated region, which is characterized by significant gaps in the socioeconomic levels particularly between the North (Europe) and South (Africa), parallel with population growth and migration, increased water demand and forest fires risk-the vulnerability of the Mediterranean population to human health risks increases significantly. Indeed, climatic changes impact the health of the Mediterranean population directly through extreme heat, drought or storms, or indirectly by changes in water availability, food provision and quality, air pollution and other stressors. The main health effects are related to extreme weather events (including extreme temperatures and floods), changes in the distribution of climate-sensitive diseases and changes in environmental and social conditions. The poorer countries, particularly in North Africa and the Levant, are at highest risk. Climate change affects the vulnerable sectors of the region, including an increasingly older population, with a larger percentage of those with chronic diseases, as well as poor people, which are therefore more susceptible to the effects of extreme temperatures. For those populations, a better surveillance and control systems are especially needed. In view of the climatic projections and the vulnerability of Mediterranean countries, climate change mitigation and adaptation become ever more imperative. It is important that prevention Health Action Plans will be implemented , particularly in those countries that currently have no prevention plans. Most adaptation measures are "win-win situation" from a health perspective, including reducing air pollution or providing shading solutions. Additionally, Mediterranean countries need to enhance cross-border collaboration, as adaptation to many of the health risks requires collaboration across borders and also across the different parts of the basin.
The Mediterranean Basin is undergoing a warming trend with longer and warmer summers, an increase in the frequency and the severity of heat waves, changes in precipitation patterns and a reduction in rainfall amounts. In this unique populated region, which is characterized by significant gaps in the socio-economic levels particularly between the North (Europe) and South (Africa), parallel with population growth and migration, increased water demand and forest fires risk - the vulnerability of the Mediterranean population to human health risks increases significantly.
Indeed, climatic changes impact the health of the Mediterranean population directly through extreme heat, drought or storms, or indirectly by changes in water availability, food provision and quality, air pollution and other stressors. The main health effects are related to extreme weather events (including extreme temperatures and floods), changes in the distribution of climate-sensitive diseases and changes in environmental and social conditions. The poorer countries, particularly in North Africa and the Levant, are at highest risk. Climate change affects the vulnerable sectors of the region, including an increasingly older population, with a larger percentage of those with chronic diseases, as well as poor people, which are therefore more susceptible to the effects of extreme temperatures. For those populations, a better surveillance and control systems are especially needed. In view of the climatic projections and the vulnerability of Mediterranean countries, climate change mitigation and adaptation become ever more imperative. It is important that prevention Health Action Plans will be implemented, particularly in those countries that currently have no prevention plans. Most adaptation measures are "win-win situation" from a health perspective, including reducing air pollution or providing shading solutions. Additionally, Mediterranean countries need to enhance cross-border collaboration, as adaptation to many of the health risks requires collaboration across borders and also across the different parts of the basin.
Heat waves have been linked to increases in emergency-related morbidity, but more research is needed on the demographic and disease-specific aspects of these morbidities. Using a case-crossover approach, over 700,000 daily emergency department hospital admissions in Charlottesville, Virginia, U.S.A. from 2005⁻2016 are compared between warm season heat wave and non-heat wave periods. Heat waves are defined based on the exceedance, for at least three consecutive days, of two apparent temperature thresholds (35 °C and 37 °C) that account for 3 and 6% of the period of record. Total admissions and admissions for whites, blacks, males, females, and 20⁻49 years old are significantly elevated during heat waves, as are admissions related to a variety of diagnostic categories, including diabetes, pregnancy complications, and injuries and poisoning. Evidence that heat waves raise emergency department admissions across numerous demographic and disease categories suggests that heat exerts comorbidity influences that extend beyond the more well-studied direct relationships such as heat strokes and cardiac arrest.
The Lancet Countdown tracks progress on health and climate change and provides an independent assessment of the health effects of climate change, the implementation of the Paris Agreement, and the health implications of these actions. It follows on from the work of the 2015 Lancet Commission on Health and Climate Change, which concluded that anthropogenic climate change threatens to undermine the past 50 years of gains in public health, and conversely, that a comprehensive response to climate change could be “the greatest global
health opportunity of the 21st century”. The Lancet Countdown is a collaboration between 24 academic institutions and intergovernmental organisations based in every continent and with representation from a wide range of disciplines. The collaboration includes climate scientists, ecologists, economists, engineers, experts in energy, food, and transport systems, geographers, mathematicians, social and political scientists, public health professionals, and doctors. It reports annual indicators across five sections: climate change impacts, exposures, and vulnerability; adaptation planning and resilience for health; mitigation actions and health co-benefits; economics and finance; and public and political engagement. The key messages from the 40 indicators in the Lancet Countdown’s 2017 report are summarised below.
Background:
Temporal variation of temperature-health associations depends on the combination of two pathways: pure adaptation to increasingly warmer temperatures due to climate change, and other attenuation mechanisms due to non-climate factors such as infrastructural changes and improved health care. Disentangling these pathways is critical for assessing climate change impacts and for planning public health and climate policies. We present evidence on this topic by assessing temporal trends in cold- and heat-attributable mortality risks in a multi-country investigation.
Methods:
Trends in country-specific attributable mortality fractions (AFs) for cold and heat (defined as below/above minimum mortality temperature, respectively) in 305 locations within 10 countries (1985-2012) were estimated using a two-stage time-series design with time-varying distributed lag non-linear models. To separate the contribution of pure adaptation to increasing temperatures and active changes in susceptibility (non-climate driven mechanisms) to heat and cold, we compared observed yearly-AFs with those predicted in two counterfactual scenarios: trends driven by either (1) changes in exposure-response function (assuming a constant temperature distribution), (2) or changes in temperature distribution (assuming constant exposure-response relationships). This comparison provides insights about the potential mechanisms and pace of adaptation in each population.
Results:
Heat-related AFs decreased in all countries (ranging from 0.45-1.66% to 0.15-0.93%, in the first and last 5-year periods, respectively) except in Australia, Ireland and UK. Different patterns were found for cold (where AFs ranged from 5.57-15.43% to 2.16-8.91%), showing either decreasing (Brazil, Japan, Spain, Australia and Ireland), increasing (USA), or stable trends (Canada, South Korea and UK). Heat-AF trends were mostly driven by changes in exposure-response associations due to modified susceptibility to temperature, whereas no clear patterns were observed for cold.
Conclusions:
Our findings suggest a decrease in heat-mortality impacts over the past decades, well beyond those expected from a pure adaptation to changes in temperature due to the observed warming. This indicates that there is scope for the development of public health strategies to mitigate heat-related climate change impacts. In contrast, no clear conclusions were found for cold. Further investigations should focus on identification of factors defining these changes in susceptibility.
Climate change is expected to increase heat-related and decrease cold-related mortality. The extent of acclimatization of the population to gradually-changing thermal conditions is not well understood. We aimed to define the relationship between mortality and temperature extremes in different age groups in the Helsinki-Uusimaa hospital district in Southern Finland, and changes in sensitivity of the population to temperature extremes over the period of 1972–2014. Time series of mortality were made stationary with a method that utilizes 365-day Gaussian smoothing, removes trends and seasonality, and gives relative mortality as the result. We used generalized additive models to examine the association of relative mortality to physiologically equivalent temperature (PET) and to air temperature in the 43-year study period and in two 21-year long sub-periods (1972–1992 and 1994–2014). We calculated the mean values of relative mortality in percentile-based categories of thermal indices. Relative mortality increases more in the hot than in the cold tail of the thermal distribution. The increase is strongest among those aged 75 years and older, but is somewhat elevated even among those younger than 65 years. Above the 99th percentile of the PET distribution, the all-aged relative mortality decreased in time from 18.3 to 8.6%. Among those ≥75 years old, the decrease in relative mortality between the sub-periods were found to be above the 90th percentile. The dependence of relative mortality on cold extremes was negligible, except among those ≥75 years old, in the latter period. Thus, heat-related mortality is also remarkable in Finland, but the sensitivity to heat stress has decreased over the decades.
Introduction
Our study aims at identifying and quantifying the relationship between the cold and heat exposure and the risk of cardiovascular mortality through a systematic review and meta-analysis.
Material and Methods
A systematic review and meta-analysis were conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Peer-reviewed studies about the temperature and cardiovascular mortality were retrieved in the MEDLINE, Web of Science, and Scopus databases from January 2000 up to the end of 2015. The pooled effect sizes of short-term effect were calculated for the heat exposure and cold exposure separately. Also, we assessed the dose–response relationship of temperature-cardiovascular mortality by a change in units of latitudes, longitude, lag days and annual mean temperature by meta-regression.
Result
After screening the titles, abstracts and full texts, a total of 26 articles were included in the meta-analysis. The risk of cardiovascular mortality increased by 5% (RR, 1.055; 95% CI [1.050–1.060]) for the cold exposure and 1.3% (RR, 1.013; 95% CI [1.011–1.015]) for the heat exposure. The short-term effects of cold and heat exposure on the risk of cardiovascular mortality in males were 3.8% (RR, 1.038; 95% CI [1.034–1.043]) and 1.1%( RR, 1.011; 95% CI [1.009–1.013]) respectively. Moreover, the effects of cold and heat exposure on risk of cardiovascular mortality in females were 4.1% (RR, 1.041; 95% CI [1.037–1.045]) and 1.4% (RR, 1.014; 95% CI [1.011–1.017]) respectively. In the elderly, it was at an 8.1% increase and a 6% increase in the heat and cold exposure, respectively. The greatest risk of cardiovascular mortality in cold temperature was in the 14 lag days (RR, 1.09; 95% CI [1.07–1.010]) and in hot temperatures in the seven lag days (RR, 1.14; 95% CI [1.09–1.17]). The significant dose–response relationship of latitude and longitude in cold exposure with cardiovascular mortality was found. The results showed that the risk of cardiovascular mortality increased with each degree increased significantly in latitude and longitude in cold exposure (0.2%, 95% CI [0.006–0.035]) and (0.07%, 95% CI [0.0003–0.014]) respectively. The risk of cardiovascular mortality increased with each degree increase in latitude in heat exposure (0.07%, 95% CI [0.0008–0.124]).
Conclusion
Our findings indicate that the increase and decrease in ambient temperature had a relationship with the cardiovascular mortality. To prevent the temperature- related mortality, persons with cardiovascular disease and the elderly should be targeted. The review has been registered with PROSPERO (registration number CRD42016037673).
Background:
The impact of heat waves on mortality and health inequalities is well documented. Very few studies have assessed the effectiveness of heat action plans (HAPs) on health, and none has used quasi-experimental methods to estimate causal effects of such programs.
Objectives:
To develop a quasi-experimental method to estimate the causal effects associated with HAPs that allows the identification of heterogeneity across sub-populations, and to apply this method specifically to the case of the Montreal HAP.
Methods:
A difference-in-differences approach was undertaken using Montreal death registry data for the summers of 2000-2007 to assess the effectiveness of the Montreal HAP, implemented in 2004, on mortality. To study equity in the effect of HAP implementation, we assessed whether the program effects were heterogeneous across sex (male vs. female), age (≥ 65 years vs. <65 years) and neighborhood education levels (first vs. third tertile). We conducted sensitivity analyses to assess the validity of the estimated causal effect of the HAP program.
Results:
We found evidence that the HAP contributed to reducing mortality on hot days, and that the mortality reduction attributable to the program was greater for elderly people and people living in low education neighborhoods.
Conclusion:
These findings show promise for programs aimed at reducing the impact of extreme temperatures and health inequities. We propose a new quasi experimental approach that can be easily applied to evaluate the impact of any program or intervention triggered when daily thresholds are reached.
Improving the effectiveness of public health interventions relies as much on the attention paid to their design and feasibility as to their evaluation. Yet, compared to the vast literature on how to evaluate interventions, there is little to guide researchers or practitioners on how best to develop such interventions in practical, logical, evidence based ways to maximise likely effectiveness. Existing models for the development of public health interventions tend to have a strong social-psychological, individual behaviour change orientation and some take years to implement. This paper presents a pragmatic guide to six essential Steps for Quality Intervention Development (6SQuID). The focus is on public health interventions but the model should have wider applicability. Once a problem has been identified as needing intervention, the process of designing an intervention can be broken down into six crucial steps: (1) defining and understanding the problem and its causes; (2) identifying which causal or contextual factors are modifiable: which have the greatest scope for change and who would benefit most; (3) deciding on the mechanisms of change; (4) clarifying how these will be delivered; (5) testing and adapting the intervention; and (6) collecting sufficient evidence of effectiveness to proceed to a rigorous evaluation. If each of these steps is carefully addressed, better use will be made of scarce public resources by avoiding the costly evaluation, or implementation, of unpromising interventions.
Background:
High concentrations of particulate matter (PM) air pollution have been associated with death and hospital admissions due to cardiovascular morbidity. However, it is not clear a) whether high levels of non-anthropogenic PM from dust storms constitute a health risk; and b) whether these health risks are exacerbated in a particular demographic.
Methods:
This study comprised all patients above 18 years old admitted to Soroka University Medical Center (1000 bed tertiary hospital, Be'er- Sheva, Israel, 2001-2010) with a primary diagnosis of acute coronary syndrome (ACS). Data on meteorological parameters and PM10 (particulate matter <10 μm in aerodiameter) were obtained from monitoring stations in the city of Be'er-Sheva. Data were analyzed using a case crossover analysis to examine the effect of dust exposure on hospitalization due to ACS and the interaction with co-morbidities and demographic factors.
Results:
There were 16,734 hospitalizations due to ACS during the study period. The estimated odds of hospitalization due to ACS was significantly associated with PM10 during non dust storm days at the same day of the exposure (lag0); OR = 1.014 (95%CI 1.001-1.027) for a 10 μg/m3 increase, while a delayed response (lag1) was found during the dust storm days; OR = 1.007 (95%CI 1.002-1.012). The effect size for the dust exposure association was larger for older (above the age of 65), female or Bedouin patients.
Conclusions:
Exposure to non-anthropogenic PM is associated with cardiovascular morbidity. Health risk associated dust exposure is gender and age specific with older women and Bedouin patients being the most vulnerable groups.
In the past few decades, several devastating heat wave events have significantly challenged public health. As these events are projected to increase in both severity and frequency in the future, it is important to assess the relationship between heat waves and the health indicators that can be used in the early warning systems to guide the public health response. Yet there is a knowledge gap in the impact of heat waves on morbidity. In this study, a comprehensive review was conducted to assess the relationship between heat waves and different morbidity indicators, and to identify the vulnerable populations. The PubMed and ScienceDirect database were used to retrieve published literature in English from 1985 to 2014 on the relationship between heat waves and morbidity, and the following MeSH terms and keywords were used: heat wave, heat wave, morbidity, hospital admission, hospitalization, emergency call, emergency medical services, and outpatient visit. Thirty-three studies were included in the final analysis. Most studies found a short-term negative health impact of heat waves on morbidity. The elderly, children, and males were more vulnerable during heat waves, and the medical care demand increased for those with existing chronic diseases. Some social factors, such as lower socioeconomic status, can contribute to heat-susceptibility. In terms of study methods and heat wave definitions, there remain inconsistencies and uncertainties. Relevant policies and guidelines need to be developed to protect vulnerable populations. Morbidity indicators should be adopted in heat wave early warning systems in order to guide the effective implementation of public health actions.
An estimated 47 million people worldwide are living with dementia in 2015, and this number is projected to triple by 2050. In the absence of a disease-modifying treatment or cure, reducing the risk of developing dementia takes on added importance. In 2014, the World Dementia Council (WDC) requested the Alzheimer's Association evaluate and report on the state of the evidence on modifiable risk factors for cognitive decline and dementia. This report is a summary of the Association's evaluation, which was presented at the October 2014 WDC meeting. The Association believes there is sufficient evidence to support the link between several modifiable risk factors and a reduced risk for cognitive decline, and sufficient evidence to suggest that some modifiable risk factors may be associated with reduced risk of dementia. Specifically, the Association believes there is sufficiently strong evidence, from a population-based perspective, to conclude that regular physical activity and management of cardiovascular risk factors (diabetes, obesity, smoking, and hypertension) reduce the risk of cognitive decline and may reduce the risk of dementia. The Association also believes there is sufficiently strong evidence to conclude that a healthy diet and lifelong learning/cognitive training may also reduce the risk of cognitive decline.
Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.
Recent investigations have reported a decline in the heat-related mortality risk during the last decades. However, these studies are frequently based on modelling approaches that do not fully characterize the complex temperature-mortality relationship, and are limited to single cities or countries.
To assess the temporal variation in heat-mortality associations in a multi-country data set using flexible modelling techniques.
We collected data for 272 locations in Australia, Canada, Japan, South Korea, Spain, UK and USA, with a total 20,203,690 deaths occurring in summer months between 1985 and 2012. The analysis was based on two-stage time series models. The temporal variation in heat-mortality relationships was estimated in each location with time-varying distributed lag non-linear models, expressed through an interaction between the transformed temperature variables and time. The estimates were pooled by country through multivariate meta-analysis.
Mortality risk due to heat appeared to decrease over time in several countries, with relative risks associated to high temperatures significantly lower in 2006 compared with 1993 in the USA, Japan, and Spain, and a non-significant decrease in Canada. Temporal changes are difficult to assess in Australia and South Korea due to low statistical power, while we found little evidence of variation in the UK. In the USA, the risk seems to be completely abated in 2006 for summer temperatures below their 99th percentile, but some significant excess persists for higher temperatures in all the countries.
We estimated a statistically significant decrease in the RR for heat-related mortality in 2006 compared to 1993 in the majority of countries included in the analysis.
Over the last two decades a number of heatwaves have brought the need for heatwave early warning systems (HEWS) to the attention of many European governments. The HEWS in Europe are operating under the assumption that there is a high correlation between observed and forecasted temperatures. We investigated the sensitivity of different temperature mortality relationships when using forecast temperatures. We modelled mortality in Stockholm using observed temperatures and made predictions using forecast temperatures from the European Centre for Medium-range Weather Forecasts to assess the sensitivity. We found that the forecast will alter the expected future risk differently for different temperature mortality relationships. The more complex models seemed more sensitive to inaccurate forecasts. Despite the difference between models, there was a high agreement between models when identifying risk-days. We find that considerations of the accuracy in temperature forecasts should be part of the design of a HEWS. Currently operating HEWS do evaluate their predictive performance; this information should also be part of the evaluation of the epidemiological models that are the foundation in the HEWS. The most accurate description of the relationship between high temperature and mortality might not be the most suitable or practical when incorporated into a HEWS.
Background:
Extreme heat is an important public health risk. Climate change will likely increase the temperatures humans are exposed to through exacerbated heat wave intensity and frequency, possibly increasing health risks from heat. To prevent adverse effects on human health, heat prevention plans and climate change adaptation strategies are being implemented. But are these measures effectively reducing heat-related mortality and morbidity? This study assesses the evidence base in 2014.
Methods:
We conducted a systematic review of peer-reviewed published literature. We applied a combined search strategy of automated search and journal content search using the electronic databases PubMed, Web of Knowledge, Biological Abstracts, CAB Abstracts and ProQuest Dissertation & Theses A&I. Quality appraisal was conducted using CASP checklists, and we identified recurrent themes in studies with content analysis methodology. We conducted sub-group analyses for two types of studies: survey and interview research on behavioral change and perception, and observational studies with regression.
Results:
30 articles were included in the review. The majority of studies (n = 17) assessed mortality or morbidity reductions with regression analysis. Overall, the assessments report a reduction of adverse effects during extreme heat in places where preventive measures have been implemented. Population perception and behavior change were assessed in five studies, none of which had carried out a pre-test. Two themes emerged from the review: methodological challenges are a major hindrance to rigorous evaluation, and what counts as proof of an effective reduction in adverse health outcomes is disputed.
Conclusions:
Attributing health outcomes to heat adaptation remains a challenge. Recent study designs are less rigorous due to difficulties assigning the counterfactual. While sensitivity to heat is decreasing, the examined studies provide inconclusive evidence on individual planned adaptation measures.
Background:
Tibet of China, with an average altitude of over 4000 m, has experienced noticeable changes in its climate over the last 50 years. The association between temperature and morbidity (most commonly represented by hospital admissions) has been documented mainly in developed countries. Little is known about patterns in China; nor have the health effects of temperature variations been closely studied in highland areas, worldwide.
Objective:
We investigated the temperature-morbidity association in Lhasa, the capital city of Tibet, using sex- and age-specific hospitalizations, excluding those due to external causes.
Methods:
A distributed lag non-linear model (DLNM) was applied to assess the nonlinear and delayed effects of temperature on morbidity (including total emergency room visits, total and cause-specific hospital admissions, sex- and age-specific non-external admissions).
Results:
High temperatures are associated with increases in morbidity, to a greater extent than low temperatures. Lag effects of high and low temperatures were cause-specific. The relative risks (RR) of high temperature for total emergency room visits and non-external hospitalizations were 1.162 (95% CI: 1.002-1.349) and 1.161 (95% CI: 1.007-1.339) respectively, for lag 0-14 days. The strongest cumulative effect of heat for lag 0-27 days was on admissions for infectious diseases (RR: 2.067, 95% CI: 1.026-4.027). Acute heat effects at lag 0 were related with increases of renal (RR: 1.478, 95% CI: 1.005-2.174) and respiratory diseases (RR: 1.119, 95% CI: 1.010-1.240), whereas immediate cold effects increased admission for digestive diseases (RR: 1.132, 95% CI: 1.002-1.282). Those ≥65 years of age and males were more vulnerable to high temperatures.
Conclusion:
We provide a first look at the temperature-morbidity relationship in Tibet. Exposure to both hot and cold temperatures resulted in increased admissions to hospital, but the immediate causes varied. We suggest that initiatives should be taken to reduce the adverse effects of temperature extremes in Tibet.
In a changing climate, increasing temperatures are anticipated to have profound health impacts. These impacts could be mitigated if individuals and communities adapt to changing exposures; however, little is known about the extent to which the population may be adapting.
To investigate the hypothesis that if adaptation is occurring, then heat-related mortality would be decreasing over time.
We used a national database of daily weather, air pollution, and age-stratified mortality rates for 105 US cities (covering 106 million people) during the summers 1987-2005. Time-varying coefficient regression models and Bayesian hierarchical models were used to estimate city-specific, regional, and national temporal trends in heat-related mortality, and to identify factors that explain variation across cities.
On average across cities, the number of deaths (per 1000 deaths) attributable to each 10°F increase in same-day temperature decreased from 51 (95% posterior interval: 42-61) in 1987 to 19 (12-27) in 2005. This decline was largest among those 75 and older, in northern regions, and in cities with cooler climates. Though central air conditioning prevalence has increased, we did not find statistically significant evidence of larger temporal declines among cities with larger increases in prevalence.
The population has become more resilient to heat over time. Yet even with this increased resilience, substantial risks of heat-related mortality remain. Based on 2005 estimates, an increase in average temperatures by 5°F (central climate projection) would lead to an additional 1,907 deaths per summer across all cities.
To assess the heterogeneity of heatwave-related impacts on mortality across different cities.
A multicity time series study.
3 largest Australian cities: Brisbane, Melbourne and Sydney.
All residents living in these cities.
Non-external causes mortality data by gender and two age groups (ie, 0-75 and 75+) for these cities during the period 1988-2009 were obtained from relevant government agencies.
Total mortality increased mostly within the same day (lag 0) or a lag of 1 day (lag 1) during almost all heatwaves in three cities. Using the heatwave definition (HWD) as the 95th centile of mean temperature for two or more consecutive days in the summer season, the relative risk for total mortality at lag 1 in Brisbane, Melbourne and Sydney was 1.13 (95% CI 1.08 to 1.19), 1.10 (95% CI 1.06 to 1.14) and 1.06 (95% CI 1.01 to 1.10), respectively. Using the more stringent HWD-the 99th centile of mean temperature for two or more consecutive days, the relative risk of total mortality at the lags of 0-2 days in Brisbane and Melbourne was 1.40 (95% CI 1.29 to 1.51) and 1.47 (95% CI 1.36 to 1.59), respectively. Elderly, particularly females, were more vulnerable to the impact of heatwaves.
A consistent and significant increase in mortality was observed during heatwaves in the three largest Australian cities, but the impacts of heatwave appeared to vary with age, gender, the HWD and geographical area.
Although the impact of temperature on mortality is well documented, relatively fewer studies have evaluated the associations of temperature with morbidity outcomes such as hospital admissions, and most studies were conducted in North America or Europe. We evaluated weather and hospital admissions including specific causes (allergic disease, asthma, selected respiratory disease, and cardiovascular disease) in eight major cities in Korea from 2003 to 2008. We also explored potential effect modification by individual characteristics such as sex and age. We used hierarchical modeling to first estimate city-specific associations between heat, cold, or heat waves and hospitalizations, and then estimated overall effects. Stratified analyses were performed by cause of hospitalization, sex, and age (0-14, 15-64, 65-74, and ≥75 years). Cardiovascular hospitalizations were significantly associated with high temperature, whereas hospitalizations for allergic disease, asthma, and selected respiratory disease were significantly associated with low temperature. The overall heat effect for cardiovascular hospitalization was a 4.5 % (95 % confidence interval 0.7, 8.5 %) increase in risk comparing hospitalizations at 25 to 15 °C. For cold effect, the overall increase in risk of hospitalizations comparing 2 with 15 °C was 50.5 (13.7, 99.2 %), 43.6 (8.9, 89.5 %), and 53.6 % (9.8, 114.9 %) for allergic disease, asthma, and selected respiratory disease, respectively. We did not find statistically significant effects of heat waves compared with nonheat wave days. Our results suggest susceptible populations such as women and younger persons. Our findings provide suggestive evidence that both high and low ambient temperatures are associated with the risk of hospital admissions, particularly in women or younger person, in Korea.
Mortality has been shown to increase with heat waves. Serbia experienced the hottest heat wave in July 2007. In this study, we examined patterns of non-traumatic excess mortality in Belgrade during this event.
The numbers of deaths observed during the 9-day heat wave were compared to those expected on the basis of mortality rates reported for the previous eight years and two following years. Excess mortality was analyzed by age, gender and cause of death.
There was a total of 167 excess deaths (38%) between 16 and 24 July. People aged 75 years and older accounted for 151 (90%) of all excess deaths. An increase of mortality among elderly was 76% in comparison to the baseline mortality. Excess female mortality was over two times higher than excess male mortality (54% : 23%). The biggest increase in mortality was from diabetes mellitus (286%), chronic kidney disease (200%), respiratory system diseases (73%), and nervous system diseases (67%). Cardiovascular and malignant neoplasms mortality accounted for the highest absolute numbers of excess deaths (77 and 49, respectively). There was no decrease in mortality in the 60-day period after the heat wave.
There are several causes of an increase in heat-related mortality. The most vulnerable population group is the elderly females.
There is limited evidence for the impacts of heat waves on coronary heart disease (CHD) mortality in Beijing, capital city of China.
We aimed to find a best heat wave definition for CHD mortality; and explore the characteristic of heat wave effects on CHD in Beijing, China.
We obtained daily data on weather and CHD mortality in Beijing for years 2000-2011. A quasi-Poisson regression model was used to assess the short-term impact of heat waves on CHD mortality in hot season (May-September), while controlling for relative humidity, day of the week, long-term trend and season. We compared 18 heat wave definitions by combining heat wave thresholds (87.5(th), 90.0(th), 92.5(th), 95(th), 97.5(th), and 99(th) percentile of daily mean temperature) with different duration days (≥ 2 to ≥ 4 days), using Akaike information criterion for quasi-Poisson. We examined whether heat wave effects on CHD mortality were modified by heat wave duration and timing.
Heat wave definition using 97.5(th) percentile of daily mean temperature (30.5 °C) and duration ≥ 2 days produced the best model fit. Based on this heat wave definition, we found that men and elderly were sensitive to the first heat waves of the season, while women and young were sensitive to the second heat waves. In general, the longer duration of heat waves increased the risks of CHD mortality more than shorter duration for elderly. The first two days of heat waves had the highest impact on CHD mortality. Women and elderly were at higher risks than men and young when exposed to heat waves, but the effect differences were not statistically significant.
Heat waves had significant impact on CHD mortality. This finding may have implications for policy making towards protecting human health from heat waves.
To explore the relationship between weather phenomena and pollution levels and daily hospital admissions (as an approximation to morbidity patterns) in Hong Kong Special Administrative Region (SAR), China, in 1998-2009.
Generalized additive models and lag models were constructed with data from official sources on hospital admissions and on mean daily temperature, mean daily wind speed, mean relative humidity, daily total global solar radiation, total daily rainfall and daily pollution levels.
During the hot season, admissions increased by 4.5% for every increase of 1 °C above 29 °C; during the cold season, admissions increased by 1.4% for every decrease of 1 °C within the 8.2-26.9 °C range. In subgroup analyses, admissions for respiratory and infectious diseases increased during extreme heat and cold, but cardiovascular disease admissions increased only during cold temperatures. For every increase of 1 °C above 29 °C, admissions for unintentional injuries increased by 1.9%. During the cold season, for every decrease of 1 °C within the 8.2-26.9 °C range, admissions for cardiovascular diseases and intentional injuries rose by 2.1% and 2.4%, respectively. Admission patterns were not sensitive to sex. Admissions for respiratory diseases rose during hot and cold temperatures among children but only during cold temperatures among the elderly. In people aged 75 years or older, admissions for infectious diseases rose during both temperature extremes.
In Hong Kong SAR, hospitalizations rise during extreme temperatures. Public health interventions should be developed to protect children, the elderly and other vulnerable groups from excessive heat and cold.
This study was conducted to investigate the relationship between heat-related illnesses developed in the summer of 2012 and temperature.
The study analyzed data generated by a heat wave surveillance system operated by the Korea Centers for Disease Control and Prevention during the summer of 2012. The daily maximum temperature, average temperature, and maximum heat index were compared to identify the most suitable index for this study. A piecewise linear model was used to identify the threshold temperature and the relative risk (RR) above the threshold temperature according to patient characteristics and region.
The total number of patients during the 3 months was 975. Of the three temperature indicators, the daily maximum temperature showed the best goodness of fit with the model. The RR of the total patient incidence was 1.691 (1.641 to 1.743) per 1℃ after 31.2℃. The RR above the threshold temperature of women (1.822, 1.716 to 1.934) was greater than that of men (1.643, 1.587 to 1.701). The threshold temperature was the lowest in the age group of 20 to 64 (30.4℃), and the RR was the highest in the ≥65 age group (1.863, 1.755 to 1.978). The threshold temperature of the provinces (30.5℃) was lower than that of the metropolitan cities (32.2℃). Metropolitan cities at higher latitudes had a greater RR than other cities at lower latitudes.
The influences of temperature on heat-related illnesses vary according to gender, age, and region. A surveillance system and public health program should reflect these factors in their implementation.
Background:
This multicenter study is aimed at estimating changes in the effect of high temperatures on elderly mortality before and after the 2003 heat waves and following the introduction of heat prevention activities.
Methods:
A total of sixteen cities were included in the study. City-specific relationships between maximum apparent temperature (MAT) and elderly daily mortality before (1998-2002) and after (2006-2010) intervention were modelled through non-linear distributed lag models and estimates were combined using a random effect meta-analysis. We estimated the percentage change in daily mortality for 3°C variations in MAT above the 25th percentile of the June city-specific 1998-2002 distribution. A time-varying analysis was carried out to describe intra-seasonal variations in the two periods.
Results:
We observed a reduction in high temperatures' effect post intervention; the greatest reduction was for increases in temperature from 9°C to 12°C above the 25th percentile, with a decrease from +36.7% to +13.3%. A weak effect was observed for temperatures up to 3°C above the 25th percentile only after. Changes were month-specific with a reduction in August and an increase in May, June and September in 2006-2010.
Conclusions:
A change in the temperature-mortality relationship was observed, attributable to variations in temperature distributions during summer and to the introduction of adaptation measures. The reduction in the effect of high temperature suggests that prevention programs can mitigate the impact. An effect of lower temperature remains, indicating a relevant impact of temperature at the beginning of summer when the population has not yet adapted and intervention activities are not fully operational.
Background: Although many climate-sensitive environmental exposures are related to mortality and morbidity, there is a paucity of estimates of the public health burden attributable to climate change.
Objective: We estimated the excess current and future public health impacts related to respiratory hospitalizations attributable to extreme heat in summer in New York State (NYS) overall, its geographic regions, and across different demographic strata.
Methods: On the basis of threshold temperature and percent risk changes identified from our study in NYS, we estimated recent and future attributable risks related to extreme heat due to climate change using the global climate model with various climate scenarios. We estimated effects of extreme high apparent temperature in summer on respiratory admissions, days hospitalized, direct hospitalization costs, and lost productivity from days hospitalized after adjusting for inflation.
Results: The estimated respiratory disease burden attributable to extreme heat at baseline (1991–2004) in NYS was 100 hospital admissions, US$644,069 in direct hospitalization costs, and 616 days of hospitalization per year. Projections for 2080–2099 based on three different climate scenarios ranged from 206–607 excess hospital admissions, US$26–$76 million in hospitalization costs, and 1,299–3,744 days of hospitalization per year. Estimated impacts varied by geographic region and population demographics.
Conclusions: We estimated that excess respiratory admissions in NYS due to excessive heat would be 2 to 6 times higher in 2080–2099 than in 1991–2004. When combined with other heat-associated diseases and mortality, the potential public health burden associated with global warming could be substantial.
The health impact of climate change depends on various conditions at any given time and place, as well as on the person. Temporal variations in the relationship between high temperature and mortality need to be explored in depth to explain how changes in the level of exposure and public health interventions modify the temperature-mortality relationship. We examined changes in the relationship between human mortality and temperature in Seoul, which has the highest population in South Korea, considering the change in population structure from 1993-2009. Poisson regression models were used to estimate short-term temperature-related mortality impacts. Temperature-related risks were divided into two "time periods" of approximately equal length (1993 and 1995-2000, and 2001-2009), and were also examined according to early summer and late summer. Temperature-related mortality in summer over the past 17 years has declined. These decreasing patterns were stronger for cardiovascular disease-related mortality than for all non-accidental deaths. The novel finding is that declines in temperature-related mortality were particularly noteworthy in late summer. Our results indicate that temperature-related mortality is decreasing in Seoul, particularly during late summer and, to a lesser extent, during early summer. This information would be useful for detailed public health preparedness for hot weather.
Background In recent years there has been a notable increase in respiratory diseases in industrialised countries, which is attributed
to a combination of chemical atmospheric pollution and the allergens existing in the atmosphere of big cities. Few studies,
however, have analysed the effect of different pollen species on the different causes of hospital admissions other than those
exclusively owing to asthma. Objective The aim of this investigation was to analyse the influence of the most abundant pollen species with the highest allergenic
potential in Madrid’s atmosphere on daily emergency hospital admissions – from all causes and specific causes – according
to different age groups. Methods An ecological time-series design was adopted in which the effects were quantified using Poisson regression models, taking
into account different confusion factors, such as chemical and acoustic atmospheric pollution. Results Statistically significant associations were found between pollen species and hospital admissions due to respiratory causes,
and between pollen species and all causes of hospital admissions and, to a lesser degree, circulatory causes. The impact was
greater in the younger age groups. Concentrations of Poaceae and Platanus pollen species were the factors showing the highest correlation to the different causes of admission. Conclusion The relative risks analysis revealed a significant effect between the pollen species analysed and health for admitted patients
of all age groups; this effect was greater than that detected for the environmental variables traditionally analysed in urban
atmospheres.
One of the key climate change factors, temperature, has potentially grave implications for human health. We report the first attempt to investigate the association between the daily 3-hour maximum apparent temperature (Tapp(max)) and respiratory (RD), cardiovascular (CVD), and cerebrovascular (CBD) emergency hospital admissions in Copenhagen, controlling for air pollution. The study period covered 1 January 2002-31 December 2006, stratified in warm and cold periods. A case-crossover design was applied. Susceptibility (effect modification) by age, sex, and socio-economic status was investigated. For an IQR (8°C) increase in the 5-day cumulative average of Tapp(max), a 7% (95% CI: 1%, 13%) increase in the RD admission rate was observed in the warm period whereas an inverse association was found with CVD (-8%, 95% CI: -13%, -4%), and none with CBD. There was no association between the 5-day cumulative average of Tapp(max) during the cold period and any of the cause-specific admissions, except in some susceptible groups: a negative association for RD in the oldest age group and a positive association for CVD in men and the second highest SES group. In conclusion, an increase in Tapp(max) is associated with a slight increase in RD and decrease in CVD admissions during the warmer months.
The present study aimed at developing a standardized heat wave definition to estimate and compare the impact on mortality by gender, age and death causes in Europe during summers 1990-2004 and 2003, separately, accounting for heat wave duration and intensity.
Heat waves were defined considering both maximum apparent temperature and minimum temperature and classified by intensity, duration and timing during summer. The effect was estimated as percent increase in daily mortality during heat wave days compared to non heat wave days in people over 65 years. City specific and pooled estimates by gender, age and cause of death were calculated.
The effect of heat waves showed great geographical heterogeneity among cities. Considering all years, except 2003, the increase in mortality during heat wave days ranged from + 7.6% in Munich to + 33.6% in Milan. The increase was up to 3-times greater during episodes of long duration and high intensity. Pooled results showed a greater impact in Mediterranean (+ 21.8% for total mortality) than in North Continental (+ 12.4%) cities. The highest effect was observed for respiratory diseases and among women aged 75-84 years. In 2003 the highest impact was observed in cities where heat wave episode was characterized by unusual meteorological conditions.
Climate change scenarios indicate that extreme events are expected to increase in the future even in regions where heat waves are not frequent. Considering our results prevention programs should specifically target the elderly, women and those suffering from chronic respiratory disorders, thus reducing the impact on mortality.
Since 2004, the Italian Department for Civil Protection and the Ministry of Health have implemented a national program for the prevention of heat-health effects during summer, which to-date includes 34 major cities and 93% of the residents aged 65 years and over. The Italian program represents an important example of an integrated approach to prevent the impact of heat on health, comprising Heat Health Watch Warning Systems, a mortality surveillance system and prevention activities targeted to susceptible subgroups. City-specific warning systems are based on the relationship between temperature and mortality and serve as basis for the modulation of prevention measures. Local prevention activities, based on the guidelines defined by the Ministry of Health, are constructed around the infrastructures and services available. A key component of the prevention program is the identification of susceptible individuals and the active surveillance by General Practitioners, medical personnel and social workers. The mortality surveillance system enables the timely estimation of the impact of heat, and heat waves, on mortality during summer as well as to the evaluation of warning systems and prevention programs. Considering future predictions of climate change, the implementation of effective prevention programs, targeted to high risk subjects, become a priority in the public health agenda.
Many of the studies that analyze the future impact of climate change on mortality assume that the temperature that constitutes a heat wave will not change over time. This is unlikely, however, given the process of adapting to heat changes, prevention plans, and improvements in social and health infrastructure.
The objective of this study is to analyze whether, during the 1983-2013 period, there has been a temporal change in the maximum daily temperatures that constitute a heat wave (Tthreshold) in Spain, and to investigate whether there has been variation in the attributable risk (AR) associated with mortality due to high temperatures in this period.
This study uses daily mortality data for natural causes except accidents CIEX: A00-R99 in municipalities of over 10,000 inhabitants in 10 Spanish provinces and maximum temperature data from observatories located in province capitals. The time series is divided into three periods: 1983-1992, 1993-2003 and 2004-2013. For each period and each province, the value of Tthreshold was calculated using scatter-plot diagram of the daily mortality pre-whitened series, and relative risks (RR) and attributable risks (AR) were calculated using generalized linear model (GLM) methodology with the Poisson regression link. Global RR and AR were calculated via a meta-analysis for the total of the 10 provinces.
The results show that in the first two periods RR remained constant RR: 1.14 (CI95%: 1.09 1.19) and RR: 1.14 (CI95%: 1.10 1.18), while the third period shows a sharp decrease with respect to the prior two periods RR: 1.01 (CI95%: 1.00 1.01); the difference is statistically significant.
In Spain there has been a sharp decrease in mortality attributable to heat over the past 10 years. This decrease coincides in time with the implementation of the High Temperature Prevention Plan. The observed variation in RR puts into question the results of numerous studies that analyze the future impact of heat on mortality in different temporal scenarios and show it to be constant over time.
Background:
Excessive summer heat is a serious environmental health problem in several European cities. Heat-related mortality and morbidity is likely to increase under climate change scenarios without adequate prevention based on locally relevant evidence.
Methods:
We modelled the urban climate of Antwerp for the summer season during the period 1986-2015, and projected summer daily temperatures for two periods, one in the near (2026-2045) and one in the far future (2081-2100), under the Representative Concentration Pathway (RCP) 8.5. We then analysed the relationship between temperature and mortality, as well as with hospital admissions for the period 2009-2013, and estimated the projected mortality in the near future and far future periods under changing climate and population, assuming alternatively no acclimatization and acclimatization based on a constant threshold percentile temperature.
Results:
During the sample period 2009-2013 we observed an increase in daily mortality from a maximum daily temperature of 26°C, or the 89th percentile of the maximum daily temperature series. The annual average heat-related mortality in this period was 13.4 persons (95% CI: 3.8-23.4). No effect of heat was observed in the case of hospital admissions due to cardiorespiratory causes. Under a no acclimatization scenario, annual average heat-related mortality is multiplied by a factor of 1.7 in the near future (24.1deaths/year CI 95%: 6.78-41.94) and by a factor of 4.5 in the far future (60.38deaths/year CI 95%: 17.00-105.11). Under a heat acclimatization scenario, mortality does not increase significantly in the near or in the far future.
Conclusion:
These results highlight the importance of a long-term perspective in the public health prevention of heat exposure, particularly in the context of a changing climate, and the calibration of existing prevention activities in light of locally relevant evidence.
Spain’s current heat wave prevention plans are activated according to administratively areas. This study analyses the determination of threshold temperatures for triggering prevention-plan activation by reference to isoclimatic areas, and describes the public health benefits.We subdivided the study area -the Madrid Autonomous Region (MAR)- into three, distinct, isoclimatic areas: “North”, “Central” and “South”, and grouped daily natural-cause mortality (ICD-10: A00-R99) in towns of over 10,000 inhabitants (2000-2009 period) accordingly. The independent variable was the maximum daily temperature (ºC), with temperature-mortality scatter-plot diagrams being used to determine the specific threshold temperatures. To ascertain the increase in Relative Risk (RR) and Attributable Risk (AR) in each of these areas, we constructed generalised linear time-series models.The thresholds set for each area were maximum daily temperatures of 26 ºC for “North area”, 36ºC for “Central area”, and 38º C for “South area”, corresponding to the 87th, 95th and 92nd percentiles respectively of the maximum temperature series for the summer months. The RR CI 95% are 1.09 (1.04 1.15), 1.16 (1.13 1.19), 1.17 (1.08 1.28) respectively. Using these three areas rather than the MAR as a whole would have resulted in a possible decrease in mortality of 73 persons (38-108) in the North area, and in aborting unnecessary activation of the plan 153 times in the Central area and 417 times in the South area. Our results indicate that extrapolating this methodology would bring benefits associated with a reduction in attributable mortality and improved effectiveness of public health interventions.
Background/objectives:
Low birth weight (<2500 g) (LBW), premature birth (<37 weeks of gestation) (PB), and late foetal death (<24 h of life) (LFD) are causes of perinatal morbi-mortality, with short- and long-term social and economic health impacts. This study sought to identify gestational windows of susceptibility during pregnancy and to analyse and quantify the impact of different air pollutants, noise and temperature on the adverse birth outcomes.
Methods:
Time-series study to assess the impact of mean daily PM2.5, NO2 and O3 (μg/m(3)), mean daily diurnal (Leqd) and nocturnal (Leqn) noise levels (dB(A)), maximum and minimum daily temperatures (°C) on the number of births with LBW, PB or LFD in Madrid across the period 2001-2009. We controlled for linear trend, seasonality and autoregression. Poisson regression models were fitted for quantification of the results. The final models were expressed as relative risk (RR) and population attributable risk (PAR).
Results:
Leqd was observed to have the following impacts in LBW: at onset of gestation, in the second trimester and in the week of birth itself. NO2 had an impact in the second trimester. In the case of PB, the following: Leqd in the second trimester, Leqn in the week before birth and PM2.5 in the second trimester. In the case of LFD, impacts were observed for both PM2.5 in the third trimester, and minimum temperature. O3 proved significant in the first trimester for LBW and PB, and in the second trimester for LFD.
Conclusions:
Pollutants concentrations, noise and temperature influenced the weekly average of new-borns with LBW, PB and LFD in Madrid. Special note should be taken of the effect of diurnal noise on LBW across the entire pregnancy. The exposure of pregnant population to the environmental factors analysed should therefore be controlled with a view to reducing perinatal morbi-mortality.
Heat response plans are becoming increasingly more common as US cities prepare for heat waves and other effects of climate change. Standard elements of heat response plans exist, but plans vary depending on geographic location and distribution of vulnerable populations. Because heat events vary over time and affect populations differently based on vulnerability, it is difficult to compare heat response plans and evaluate responses to heat events. This article provides an overview of the Baltimore City heat response plan, the Code Red program, and discusses the city's response to the 2012 Ohio Valley/Mid Atlantic Derecho, a complex heat event. Challenges with and strategies for evaluating the program are reviewed and shared.
Background: Parkinson's disease (PD) is one of the factors which are associated with a higher risk of mortality during heat waves. The use of certain neuroleptic medications to control some of this disease's complications would appear to be related to an increase in heat-related mortality.
Objective: To analyse the relationship and quantify the short-term effect of high temperatures during heat wave episodes in Madrid on daily mortality and PD-related hospital admissions.
Methods: We used an ecological time-series study and fit Poisson regression models. We analysed the daily number of deaths due to PD and the number of daily PD-related emergency hospital admissions in the city of Madrid, using maximum daily temperature (°C) as the main environmental variable and chemical air pollution as covariates. We controlled for trend, seasonalities, and the autoregressive nature of the series.
Results: There was a maximum daily temperature of 30°C at which PD-related admissions were at a minimum. Similarly, a temperature of 34°C coincides with an increase in the number of admissions. For PD-related admissions, the Relative Risk (RR) for every increase of 1°C above the threshold temperature was 1.13 IC95%:(1.03 - 1.23) at lags 1 and 5; and for daily PD-related mortality, the RR was 1.14 IC95%:(1.01 - 1.28) at lag 3.
Conclusion: Our results indicate that suffering from PD is a risk factor that contributes to the excess morbidity and mortality associated with high temperatures, and is relevant from the standpoint of public health prevention plans.
Background:
Road traffic noise is a major public health issue, given the documented association with several diseases and the growing number of exposed persons all over the world. The effects widely investigated pertain to cardiovascular health, and to a lesser extent to respiratory and metabolic health. The epidemiological design of most studies has made it possible to ascertain long-term associations of urban noise with a number of cardiovascular, respiratory, and metabolic disorders and diseases; additionally, time series studies have reported short-term associations.
Objectives:
To review the various biological mechanisms that may account for all long-term as well as short-term associations between road traffic noise and cardiovascular, respiratory, and metabolic health. We also aimed to review the neuroendocrine processes triggered by noise as a stressor and the role of the central nervous system in noise-induced autonomic responses.
Methods:
Review of the literature on road traffic noise, environmental noise in general, psychosomatics, and diseases of the cardiovascular, respiratory, and metabolic systems. The search was done using PubMed databases.
Discussion:
We present a comprehensive, integrative stress model with all known connections between the body systems, states, and processes at both the physiological and psychological levels, which allows to establish a variety of biological pathways linking environmental noise exposure with health outcomes.
Conclusions:
The long- and short-term associations between road traffic noise and health outcomes found in latest noise research may be understood in the light of the integrative model proposed here.
Background:
Climate change is projected to increase the frequency, intensity, and duration of heat waves while reducing cold extremes, yet few studies have examined the relationship between temperature and fetal health.
Objectives:
We estimate the impacts of extreme temperatures on birth weight and gestational age in Manhattan, a borough in New York City, and explore differences by socioeconomic status (SES).
Methods:
We combine average daily temperature from 1985 to 2010 with birth certificate data in Manhattan for the same time period. We then generate 33 downscaled climate model time series to project impacts on fetal health.
Results:
We find exposure to an extra day where average temperature <25°F and >85°F during pregnancy is associated with a 1.8 and 1.7g (respectively) reduction in birth weight, but the impact varies by SES, particularly for extreme heat, where teen mothers seem most vulnerable. We find no meaningful, significant effect on gestational age. Using projections of temperature from these climate models, we project average net reductions in birth weight in the 2070-2099 period of 4.6g in the business-as-usual scenario.
Conclusions:
Results suggest that increasing heat events from climate change could adversely impact birth weight and vary by SES.
A number of studies have shown that there is a time trend towards a reduction in the effects of heat on mortality. In the case of cold, however, there is practically no research of this type and so there is no clearly defined time trend of the impact of cold on mortality. Furthermore, no other specific studies have yet analysed the time trend of the impact of both thermal extremes by age group.
We analysed data on daily mortality due to natural causes (ICD-10: A00-R99) in the city of Madrid across the period 2001-2009 and calculated the impact of extreme temperatures on mortality using Poisson regression models for specific age groups, namely, <1, 1-17, 18-44, 45-66, 65-74 and over-75 years. We controlled for confounding variables, such as air pollution, noise, influenza, pollen, pressure and relative humidity, trend of the series, as well as seasonalities and autoregressive components of the series. The results of these models were compared to those obtained for the same city during the period 1986-1997 and published in different studies.
Our results show a clear reduction in the effects of heat, especially in the over-45-year age group, with an increase solely in the 18-44 age group. In the case of cold, the behaviour pattern was the opposite, with an increase in its effect across all age groups, and even an effect on mortality detected among persons under the age of 18 years. Heat adaptation and socio-economic and public-health prevention and action measures may be behind this amelioration in the effects of heat, whereas the absence of such actions in respect of low temperatures may account for the increase in the effects of cold on mortality. From a public health point of view, the implementation of cold wave prevention plans covering all age groups is thus called for.
A decade after the implementation of prevention plans designed to minimise the impact of high temperatures on health, some countries have decided to update these plans in order to improve the weakness detected in these ten years of operation.
In the case of Spain, this update has fundamentally consisted of changing the so-called “threshold” or “trigger”
temperatures used to activate the plan, by switching from temperature values based on climatological criteria
to others obtained by epidemiological studies conducted on a provincial scale.
This study reports the results of these “trigger” temperatures for each of Spain's 52 provincial capitals, as well as the impact of heat on mortality by reference to the relative risks (RRs) and attributable risks (ARs) calculated for natural as well as circulatory and respiratory causes.
The results obtained for threshold temperatures and RRs show a more uniform behaviour pattern than those obtained
using temperature values based on climatological criteria; plus a clear decrease in RRs of heat-associated
mortality due to the three causes considered, at both a provincial and regional level as well as for Spain as a
whole.
The updating of prevention plans is regarded as crucial for optimising the operation of these plans in terms of
reducing the effect of high temperatures on population health.
Episodes of extremely hot or cold temperatures are associated with increased mortality. Time-series analyses show an association between temperature and mortality across a range of less extreme temperatures. In this paper, the authors describe the temperature-mortality association for 11 large eastern US cities in 1973-1994 by estimating the relative risks of mortality using log-linear regression analysis for time-series data and by exploring city characteristics associated with variations in this temperature-mortality relation. Current and recent days' temperatures were the weather components most strongly predictive of mortality, and mortality risk generally decreased as temperature increased from the coldest days to a certain threshold temperature, which varied by latitude, above which mortality risk increased as temperature increased. The authors also found a strong association of the temperature-mortality relation with latitude, with a greater effect of colder temperatures on mortality risk in more-southern cities and of warmer temperatures in more-northern cities. The percentage of households with air conditioners in the south and heaters in the north, which serve as indicators of socioeconomic status of the city population, also predicted weather-related mortality. The model developed in this analysis is potentially useful for projecting the consequences of climate-change scenarios and offering insights into susceptibility to the adverse effects of weather.
The relationship between heat waves and mortality has been widely described, but there are few studies using long daily data on specific-cause mortality. This study is undertaken in central Spain and analysing natural causes, circulatory and respiratory causes of mortality from 1975 to 2008. Time-series analysis was performed using ARIMA models, including data on specific-cause mortality and maximum and mean daily temperature and mean daily air pressure. The length of heat waves and their chronological number were analysed. Data were stratified in three decadal stages: 1975-1985, 1986-1996 and 1997-2008. Heat-related mortality was triggered by a threshold temperature of 37 °C. For each degree that the daily maximum temperature exceeded 37 °C, the percentage increase in mortality due to circulatory causes was 19.3 % (17.3-21.3) in 1975-1985, 30.3 % (28.3-32.3) in 1986-1996 and 7.3 % (6.2-8.4) in 1997-2008. The increase in respiratory cause ranged from 12.4 % (7.8-17.0) in the first period, to 16.3 % (14.1-18.4) in the second and 13.7 % (11.5-15.9) in the last. Each day of heat-wave duration explained 5.3 % (2.6-8.0) increase in respiratory mortality in the first period and 2.3 % (1.6-3.0) in the last. Decadal scale differences exist for specific-causes mortality induced by extreme heat. The impact on heat-related mortality by natural and circulatory causes increases between the first and the second period and falls significantly in the last. For respiratory causes, the increase is no reduced in the last period. These results are of particular importance for the estimation of future impacts of climate change on health.
Cases of death during heat waves are most commonly due to respiratory and cardiovascular diseases, with the main contribution from the negative effect of heat on the cardiovascular system. In an attempt to control the body temperature, the body’s natural instinct is to circulate large quantities of blood to the skin. However while trying to protect itself from overheating, the body actually harms itself by inducing extra strain on the heart. This excess strain has the potential to trigger a cardiac event in those with chronic health problems, such as the elderly. Those in the U.S.A. between the ages of 65 and 74 are at a higher risk of mortality during heat waves when they are single, have a history of chronic pulmonary disease, or suffer from a psychiatric disorder. In the older group, 75+, single people are again more vulnerable as well as women. The relationship of mortality and temperature creates a J-shaped function, showing a steeper slope at higher temperatures. Records show that more casualties have resulted from heat waves than hurricanes, floods, and tornadoes together. The significance of this is that the U.S. suffers the highest damage total from natural catastrophes annually. Studies held from 1989–2000 in 50 U.S. cities recorded 1.6% more deaths during cold temperature events, as opposed to a staggering 5.7% increase during heat waves. People are at risk when living in large metropolitan areas, especially those mentioned above, due to the heat island effect. Urban areas suffer heat increases from the combination of global warming effects as well as localized heat island properties. It is flawed to claim that the contribution of anthropogenic heat generation to the heat island effect is small. Analyzing the trend of extreme heat events (EHEs) between 1956 and 2005 showed an increase on average of 0.20 days/year, on a 95% confidence interval with uncertainty of ±0.6. This trend follows the recorded data for 2005 with 10 more heat events per city than in 1956. Compact cities experience an average of 5.6 days of extreme heat conditions annually, compared to that of 14.8 for sprawling cities. The regional climate, city populace, or pace of population growth however does not affect this effect. Statistics from the U.S. Census state that the U.S. population without air conditioning saw a drop of 32% from 1978 to 2005, resting at 15%. Despite the increase in air conditioning use, the positive affects of it may have run their course as a critical point may have been reached. A study done by Kalkstein through 2007 proved that the shielding effects of air conditioning reached their terminal effect in the mid-1990s. Heat-related illnesses and mortality rates have slightly decreased since 1980, regardless of the increase in temperatures. This may be in part to the increase in availability of air conditioning, and other protective measures, to the public. Protective factors have mitigated the danger of heat on those vulnerable to it, however projecting forward the heat increment related to sprawl may exceed physiologic adaptation thresholds.
Background:
Heat waves have been reported as being associated with increased rates of hospitalizations and deaths.
Materials and methods:
In July 2011, a heat wave hit southern Italy. We enrolled 9,282 consecutive patients who called the Apulia (southeastern Italy) regional free public emergency medical service (EMS) "118" number (out of 4 million inhabitants) during July 2011. All patients were evaluated with a prehospital electrocardiogram (ECG) thanks to telecardiology support provided by a single telemedicine hub. Local temperatures and relative humidity were recorded and combined in order to calculate the heat index (HI), a more accurate parameter to assess perceived discomfort caused by hot temperatures.
Results:
The mean number of calls to the telecardiology hub for prehospital ECG screening in the case of suspected heart disease was increased 48 h after days with an HI ≥ 44 (402 ± 68 versus 275 ± 52, p<0.001, +46%), when the number of calls was directly related to HI values (p < 0.01). ECG diagnoses of new-onset atrial fibrillation were significantly increased 24 h after days with an HI ≥ 44 (12 ± 7 versus 8 ± 3, p<0.01, +50%). ECG diagnoses of ST-elevation acute myocardial infarction, in contrast, remained substantially unchanged. No significant gender or age (>70 versus <70 years) differences were observed (chi-squared p not significant); increased rates of EMS callings were found 48 h after days with an HI ≥ 44 in hypertensive patients (131 ± 42 versus 78 ± 26, p<0.001, +68%) and subjects with prior cardiovascular disease (137 ± 43 versus 89 ± 22, p<0.001, +54%).
Conclusions:
Increased work burden for EMS assessed with prehospital telecardiology screening accompanies heat waves because of subjects calling for suspected acute heart disease. Prehospital screening with telecardiology support may be of help in identifying subjects who do not require hospitalization in the event of heat waves with increased calls to EMS.
Although a number of studies have examined potential differences in temperature regulation between males and females during heat stress, conclusions have remained limited as to whether reported differences are due to confounding physical characteristics or to actual differences in the physiological variables of temperature regulation. Recent observations suggest that sex-differences in temperature regulation, particularly in sudomotor activity, go beyond those associated with physical characteristics. Females have recently been shown to have a lower sudomotor activity, as well as a lower thermosensitivity of the response compared to males during exercise performed at a fixed rate of metabolic heat production. Furthermore, sex-differences in local and whole-body sudomotor activity are only evident above a certain combination of environmental conditions and rate of metabolic heat production. In contrast, both the onset threshold and thermosensitivity of cutaneous vasodilation are similar between males and females. In theory, differences in the thermosensitivity of sudomotor activity could be related to either a central (neural activity/integration) and/or peripheral (effector organ) modulation of temperature regulation. Based on recent findings, sex-differences in sudomotor activity appear to be mediated peripherally, albeit a central modulation has yet to be conclusively ruled out. The current review provides a brief, yet comprehensive review of the current state of knowledge pertaining to sex-differences in temperature regulation during exercise in the heat.
Daily mortality displays a seasonal pattern linked to weather, air pollution, photoperiod length, influenza incidence and diet, among which temperature ranks as a leading cause. This study thus sought to assess the relationship between temperature, relative humidity, wind speed and mortality in the Madrid Autonomous Region (Spain) for the period January 1986–December 1992, controlling for the effects of air pollution and influenza incidence. Daily data on maximum, minimum and 24-hour mean temperature, relative humidity and wind speed were matched against daily mortality. Transfer function was identified using the Box–Jenkins pre-whitening method. Multivariate time series regression models were used to control for the confounding effects of air pollution and influenza incidence. Separate seasonal analyses were carried out for winter and summer periods. A J-shaped relationship between outdoor temperature, relative humidity and daily mortality was found. Mortality proved to be inversely related to cold temperature (4- to 11-day lag) and directly related to warm temperature (1-day lag). High relative humidity during summer periods was negatively related to mortality. Thermal variation ascribable to Madrid's mesothermal Mediterranean climate was strongly related to daily mortality, even where air pollution and influenza incidence were controlled for.
The purpose of this study was to understand the effects of the July 2006 heat wave through the use of the heat index, in mortality (all causes) and morbidity (all causes, respiratory and circulatory diseases) in general, and in people over 74 years and by gender, in Porto. In this paper, the Poisson generalized additive regression model was used to estimate the impact of apparent temperature (heat index) and daily mortality and morbidity during the July 2006 heat wave. Daily mortality, morbidity and heat index were correlated with lags of apparent temperature up to 7 days using Pearson correlation. For a 1°C increase in mean apparent temperature we observed a 2.7 % (95 % CI: 1.7-3.6 %) increase in mortality (all cause), a 1.7 % (95 % CI: 0.6-2.9 %) increase in respiratory morbidity, a 2.2 % (95 % CI: 0.4-4.1 %) increase in respiratory morbidity in women, a 5.4 % (95%CI: 1.1-6.6 %) increase in chronic obstructive pulmonary morbidity, and a 7.5 % (95 % CI: 1.3-14.1 %) increase in chronic obstructive pulmonary morbidity in women, for the entire population. For people ≥ 75 years, our results showed a 3.3 % increase (95 % CI: 1.7-5.0 %) in respiratory morbidity, a 2.7 % (95 % CI: 0.4-5.1 %) increase in respiratory morbidity in men, a 3.9 % (95 %CI: 1.6-6.3 %) increase in respiratory morbidity in women, a 7.0 % (95 % CI: 1.1-13.2 %) in chronic obstructive pulmonary disease, and a 9.0 % (95 % CI: 0.3-18.5 %) in chronic obstructive pulmonary disease in women. The use of heat index in a Mediterranean tempered climate enabled the identification of the effects of the July 2006 heat wave in mortality due to all causes and in respiratory morbidity of the general population, as well as in respiratory morbidity of individuals with more than 74 years of age.
All the climate-change studies undertaken to date agree that one of the principal consequences of this phenomenon is the increase in heat waves, which, without exception, are linked to marked rises in mortality. The characteristics that modulate and determine the relationship between high temperatures and health must therefore be ascertained in the greatest possible detail, so that really effective prevention plans can be designed to address temperature extremes.
We examined the effect of heat waves on daily non-accidental-cause mortality across all age groups in the Castile-La Mancha region (Spain) from 1975 to 2003. Quantitative analyses were performed using autoregressive integrated moving average (ARIMA) models, with other covariates, such as pressure trends, relative humidity, and duration and chronological number of heat waves.
Mortality increased significantly with respect to the mean, when temperatures exceeded the designated provincial thresholds in Castile-La Mancha. For each degree centigrade that temperatures exceeded these thresholds, the percentage increase in mortality amounted to increases of approximately 12% over the daily mean, albeit with clear provincial variations. The longest heat waves were associated with daily mortality, with those at the end of summer causing the lowest mortality. Meteorological situations most closely associated with increases in mortality were cyclonic conditions accompanied by low humidity.
Spatio-temporal variability in the temperature-mortality relationship must be studied in order to enable really effective heat-wave prevention plans to be drawn up. The influence of variables, such as heat-wave duration or time of appearance, is important in the total increase in mortality during temperature extremes. Since parameters, such as humidity or pressure trends, can play very different roles in different geographical settings, they should be analysed separately from temperature.
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