Article

Mortality Related to Cold and Air Pollution in London After Allowance for Effects of Associated Weather Patterns

Authors:
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

We looked for atypical weather patterns that could confound, and explain large inconsistencies in, conventional estimates of mortality due to SO(2), CO, and smoke. Using Greater London data for 1976-1995 in the linear temperature/mortality range 0-15 degrees C we determined weather patterns associated with pollutants (all deseasonalized) by single regressions of daily temperature, wind, rain, humidity, and sunshine at successive days advance and delay. Polluted days were colder (P<0.01 for SO(2), CO, and smoke) and less windy and rainy than usual, and this cold weather was more prolonged than usual with 50% maximum temperature depression 5.9 days (95% interval 4.0-7.7) before high SO(2), compared to 2.0 (1.6-2.3) days before average cold days. We also used multiple regression of mortality at 50+ years of age on all these weather factors and pollutants at 0-, 1-, 2- to 4-, 5- to 13-, and 14- to 24-day delays to allow for the atypical weather patterns. This showed cold weather associated with 2.77 excess deaths per million during 24 days following a 1 degrees C fall for 1 day, but no net excess deaths with SO(2) (mean 28.0 ppb) or CO (1.26 ppm). It suggested (P>0.05) some increase with smoke, perhaps acting as surrogate for PM(10), for which data were too scanty to analyze.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... Perhaps the most comprehensive population-based study of cold-related mortality is the Eurowinter survey of cold-related mortality and protective measures employed in seven regions of Europe (North and South Finland, Athens, Baden-Württemberg, the Netherlands, London, and North Italy). These studies (The Eurowinter Group 1997; Keatinge et al. 2000a;Keatinge and Donaldson 2001;Keatinge 2002) found that cold-related mortality is more frequent in areas with milder winters than in areas with more severe winters, in agreement with U.S. studies (Barnett 2007;Curriero et al. 2002Curriero et al. , 2003, and Analitis et al. (2008) in a study of 15 European cities. This somewhat counterintuitive finding is thought to be due to the greater understanding of the risk posed by cold, and preparedness to deal with it, among people who live in areas that frequently experience very cold temperatures. ...
... Risk of cold-related mortality increased with age (The Eurowinter Group 1997; Keatinge et al. 2000a;Cordioli et al. 2000). Several studies have investigated cold-related mortality in London (Keatinge and Donaldson 2001;Hajat et al. 2007;Donaldson and Keatinge 2003b). Keatinge and Donaldson (2001) found that atypical patterns of prolonged cold weather were associated with episodes of elevated air pollution, which could give false indications of mortality associated with sulfur dioxide, carbon monoxide, or smoke when common epidemiological modeling techniques are used. ...
... Several studies have investigated cold-related mortality in London (Keatinge and Donaldson 2001;Hajat et al. 2007;Donaldson and Keatinge 2003b). Keatinge and Donaldson (2001) found that atypical patterns of prolonged cold weather were associated with episodes of elevated air pollution, which could give false indications of mortality associated with sulfur dioxide, carbon monoxide, or smoke when common epidemiological modeling techniques are used. The results underscore the importance of including all weather variables and lags that could impact the temperature-mortality relationship. ...
Article
DISCLAIMER This report was prepared as the result of work sponsored by the California Energy Commission (Energy Commission) and the California Environmental Protection Agency (Cal/EPA). It does not necessarily represent the views of the Energy Commission, Cal/EPA, their employees, or the State of California. The Energy Commission, Cal/EPA, the State of California, their employees, contractors, and subcontractors make no warrant, express or implied, and assume no legal liability for the information in this report; nor does any party represent that the uses of this information will not infringe upon privately owned rights.
... In terms of vulnerabilities, another important knowledge gap to be addressed are the temperature effects for the population living in substandard housing conditions in the region. Populations living in informal housing might be particularly vulnerable to non-optimum temperatures due to overcrowding, the poor quality and limited insulation of the housing, but also as a result of other interrelated factors such as poverty, lack of access to health care, sanitation and information on heat/cold wave risks, limited access to clean drinking water and electricity, and restricted household ventilation (Keatinge and Donaldson, 2001). Recent literature review in South Asia demonstrated that ambient temperature as a risk factor for all-cause mortality and for heat wave was limited and reflects the lack of a sufficient number of robust epidemiological studies in a region with very heterogenous contexts and a challenging environment for health data collection. ...
... Although the available literature on the confounding effect of air pollution suggests that modest or no modifying effect, the effects of hot and cold temperatures on mortality remain unchanged when relative humidity is accounted for. The application of combined metrics of temperature and humidity, such as apparent temperature, did not predict mortality more accurately than the single measure of temperature, and the assessment of the effect of temperature and humidity separately showed that humidity does not affect mortality (Achebak et al., 2019b;Gonçalves et al., 2007;Keatinge and Donaldson, 2001). ...
Article
Full-text available
Background Exposure to high and low ambient temperatures is associated with morbidity and mortality across the globe. Most of these studies assessing the effects of non-optimum temperatures on health and have been conducted in the developed world, whereas in India, the limited evidence on ambient temperature and health risks and has focused mostly on the effects of heat waves. Here we quantify short term association between all temperatures and mortality in urban Pune, India. Methods We applied a time series regression model to derive temperature-mortality associations based on daily mean temperature and all-cause mortality records of Pune city from year January 2004 to December 2012. We estimated high and low temperature-mortality relationships by using standard time series quasi-Poisson regression in conjunction with a distributed lag non-linear model (DLNM). We calculated temperature attributable mortality fractions for total heat and total cold. Findings The analysis provides estimates of the total mortality burden attributable to ambient temperature. Overall, 6∙5% [95%CI 1.76–11∙43] of deaths registered in the observational period were attributed to non-optimal temperatures, cold effect was greater 5.72% [95%CI 0∙70–10∙06] than heat 0∙84% [0∙35–1∙34]. The gender stratified analysis revealed that the highest burden among men both for heat and cold. Conclusion Non-optimal temperatures are associated with a substantial mortality burden. Our findings could benefit national, and local communities in developing preparedness and prevention strategies to reduce weather-related impacts immediately due to climate change.
... However, in some regions, urban areas may not experience greater heat-related mortality than in rural areas (Sheridan and Dolney 2003). The health impacts of high temperatures and high air pollution can interact, with the extent of interaction varying by location (Bates 2005; Goodman et al. 2004) (Goodman et al. 2004; Keatinge and Donaldson 2001; O'Neill et al. 2005; Ren et al. 2006). ...
... Cold also contributes to deaths caused by respiratory and cardiovascular diseases, so the overall mortality burden is likely underestimated. Factors associated with increased vulnerability to cold include black race (Fallico et al. 2005); living in Alaska, New Mexico, North Dakota, and Montana or living in a milder states that experience rapid temperature changes (North and South Carolina) and western states with greater ranges in nighttime temperatures (e.g., Arizona) (Fallico et al. 2005); having less education (O'Neill et al. 2003); and being female, having pre-existing respiratory illness (Wilkinson et al. 2004), lack of protective clothing (Donaldson et al. 2001), income inequality, fuel poverty, low residential thermal standards (Healy 2003), and living in nursing homes (Hajat et al. 2007, 2006c) and an increase in gastroenteritis cases among hurricane evacuees (CDC, 2005a). The mental health impacts (e.g. ...
... In contrast to heatwaves, extreme cold does not lead to cold-induced mortality forward displacement (Huynen et al. 2001). However, effects on mortality may persist for considerable time periods, beyond 2 weeks (Keatinge and Donaldson 2001;Carder et al. 2005), opposing the initial suggestions for immediate effects (e.g., Alberdi et al. 1998;Pattenden et al. 2003). According to Keatinge and Donaldson (2001), atypical patterns of prolonged cold weather can give false indications of mortality associated with sulfur dioxide (SO 2 ), carbon monoxide (CO), or smoke episodes. ...
... However, effects on mortality may persist for considerable time periods, beyond 2 weeks (Keatinge and Donaldson 2001;Carder et al. 2005), opposing the initial suggestions for immediate effects (e.g., Alberdi et al. 1998;Pattenden et al. 2003). According to Keatinge and Donaldson (2001), atypical patterns of prolonged cold weather can give false indications of mortality associated with sulfur dioxide (SO 2 ), carbon monoxide (CO), or smoke episodes. ...
Article
Full-text available
This article reviews interactions and health impacts of physical, chemical, and biological weather. Interactions and synergistic effects between the three types of weather call for integrated assessment, forecasting, and communication of air quality. Today's air quality legislation falls short of addressing air quality degradation by biological weather, despite increasing evidence for the feasibility of both mitigation and adaptation policy options. In comparison with the existing capabilities for physical and chemical weather, the monitoring of biological weather is lacking stable operational agreements and resources. Furthermore, integrated effects of physical, chemical, and biological weather suggest a critical review of air quality management practices. Additional research is required to improve the coupled modeling of physical, chemical, and biological weather as well as the assessment and communication of integrated air quality. Findings from several recent COST Actions underline the importance of an increased dialog between scientists from the fields of meteorology, air quality, aerobiology, health, and policy makers.
... The maximum effects were observed 3 days after the cold peak and effects lasted out to 40 days. Keatinge and Donaldson (2001) reported that a 1°C decrease in temperature was associated with 3% increase in total deaths over the next 24 days in greater London. Others have also reported strong associations between increased mortality and prolonged periods of cold weather in London (Eurowinter Group, 1997;Wilkinson et al, 1999). ...
Research
Full-text available
https://www.publichealth.ie/sites/default/files/documents/files/Fuel%20Poverty%20Report%20December%202011.pdf
... Low temperatures increase cardiovascular and respiratory morbidity and mortality. A short term exposure to temporary air pollution is effective on cardiorespiratory mortality and morbidity (26). Cold wind alone can determine mortality more than temperature can. ...
Article
Full-text available
Objective: The objective of this study is to find the relationship between incidence rate and mortality of acute pulmonary thromboembolism (PTE), and seasonal and meteorological factors. Materials and methods: The data from 234 patients who were hospitalized due to acute PTE in the emergency service or policlinics between 2001 and 2008 were investigated retrospectively. Cases that developed APE (acute pulmonary embolism) in the hospital were excluded. Seasons and months in which acute PTE was diagnosed were recorded. Mortality rates by months and seasons were evaluated. The mean pressure, temperature and humidity values were evaluated for periods of three days, seven days and one month before the day of presentation. The effects of meteorological factors on the severity (massive or non-massive) and mortality of APE were investigated. Results: The incidence rate of acute APE showed a significant difference according to seasons (p=0.000). APE was diagnosed most commonly in spring and winter. The mean pressure values for three days, seven days and one month and the mean humidity values for three days for the dead patients were found to be significantly lower than those of the survived ones (p<0.05). The mortality rate for patients admitted in summer was significantly higher than the rates for other seasons (p=0.02). There were no seasonal differences among the massive APE incidences. Mortality rates were higher in summer because of the nonmassive APE patients rather than the massive patients. Conclusion: Acute PE is a disease whose incidence and mortality rates are affected by meteorological factors.
... DTR is considered to be a risk factor for acute COPD death, independent of the absolute temperature level (Song et al. 2008;Ding et al. 2015). The exposure-response curve of temperature and mortality generally was U-or V-shaped (Keatinge and Donaldson 2001;Hajat et al. 2002;Basu and Samet 2002;Braga et al. 2002;Baccini et al. 2008), which means effects of temperature may vary between warm days (above the Binflection point^) and cold days (below the Binflection point^) (Basu and Samet 2002), and the emergency room (ER) visits will increase with the temperature rising and declining separated by the Binflection point,^respectively (Nafstad et al. 2001;Basu and Samet 2002). Some other studies reported that the exposure-response relationship between DTR and COPD mortality and respiratory mortality was linear for most levels of DTR, indicating that no threshold level was found for the association of DTR with COPD deaths (Song et al. 2008;Kan et al. 2007). ...
Article
Full-text available
Diurnal temperature range (DTR) has been suggested to be an adverse health factor especially related to respiratory and cardiovascular diseases. In the current study, we investigated the association between DTR and chronic obstructive pulmonary disease (COPD) hospital admissions during 2009 to 2012 in northeast city of Changchun, China. Based on generalized additive model (GAM), the effects were expressed as relative risk (RR) values of COPD with 95% confidence intervals (CIs) with each 1 °C increase in DTR. And they were significantly increased with an increment of 1 °C in DTR, modified by season, age, and sex. The elderly were more vulnerable, with relative risk values of 1.048 (1.029, 1.066) in cold season and 1.037 (1.021, 1.053) in warm season. Regarding the gender, the DTR effect on females was greater during cold season and the RR value was 1.051 (1.033, 1.069) on the current day (lag 0). The greater estimates for males appeared at lag 7 days, with RR of 1.019 (0.998, 1.040). A season-specific effect was detected that the relative risk values with per 1 °C increase in DTR were greater in cold season than in warm season. These findings support the hypothesis of significant relationship between DTR and COPD in Changchun, one northeast city of China.
... However, when limiting analysis to sampling days below the median temperature, we found an adverse effect of indoor temperature on respiratory symptoms. Prior research has suggested that there may exist a threshold below which colder temperatures adversely impact respiratory health [10,18] and several studies have identified 18 °C (64 °F) as a potential threshold of indoor temperature below which adverse health effects may occur [19,20]. Similarly, in a 1 week study of 148 participants with COPD living in the UK, fewer days with 9 h of warmth at 21 °C (70 °F) in the living room was associated with worse quality of life as measured by the St George's Respiratory Questionnaire [21]. ...
... For example, in 2003, a heat wave killed an estimated 35,000 Europeans (Larsen, 2006), while over 700 excess deaths were attributed to a 5-day 1995 heat event in Chicago (Semenza et al., 1996). Although the extent to which cold temperature impacts morbidity and mortality remains less clear, studies have shown physiological responses associated with cold air exposure (Holmér, Hassi, Ikäheimo, & Jaakkola, 2012; Keatinge & Donaldson, 2001; Urban, Davídkovová, & Kyselý, 2014). In addition to cold air, secondary impacts such as blizzards, floods, and daily changes in weather also impact wellbeing (Allen & Lee, 2014; Allen & Sheridan, 2014; Hickey, 2011; Kyselý, Pokorna, Kyncl, & Kriz, 2009). ...
Article
With observed increases in global temperatures indicating changes to anomalous temperature events (ATE), few studies have considered the changes associated with both heat and cold together. This study evaluates the changes in heat waves and cold spells for 55 U.S. metropolitan areas (1948–2012). Using surface observations, thresholds of mean apparent temperature were used to define heat, extreme heat, cold, and extreme cold events. Days that exceeded the 95th temperature percentile were considered heat days. Similar values were used to define extreme heat (97.5th), cold (5th), and extreme cold (2.5th). Thresholds were calculated independently for each of the locations, incorporating spatial variability into the ATE definition. Changes in duration, seasonal timing, and frequency, all of which have been shown to be important characteristics in regard to heat and cold events, were evaluated. Significant changes in some characteristics were found. Across many locations, heat events have become more frequent, longer lasting, and earlier occurring, while cold spells have experienced an opposite trend. Since heat and cold events impact a range of ecological and bioclimatological processes, understanding the variability and changes associated with ATE remains an important aspect to consider as society prepares for future events.
... Of utmost importance in clothing for alpine conditions, especially during winter seasons, is the protection against the cold. Cold alone was shown to, directly and statistically, significantly (p < 0.05) increase mortality independent of other environmental factors (Keatinge and Donaldson, 2001). The hazards associated with cold temperatures range from short-term discomfort such as chilblains to loss of life. ...
Chapter
The demands on clothing for alpine-based winter sports, competitive and recreational alike, are a fine balancing act between the physiological demands of the user and the event performance requirements (comfort vs. performance), whilst maintaining the appropriate degree of safety in one of nature’s most unpredictable and hostile environments. In the recreational activities, two major comfort aspects are considered: temperature and moisture. In competitive snow sports, comfort becomes a secondary consideration, and the focus shifts to aiding the performance of the competitor. Textiles used in alpine conditions are also discussed in a wider sense with descriptions of the inclusion of textile-based products in equipment and safety devices and their mechanical properties. A look into the current research trends and predictions of future technologies is considered with realistic applications and deliverable functionalities in mind.
... Climate and human health are deeply interconnected (McMichael, 2012). Several studies have demonstrated the impact of cold and hot weather on human mortality and morbidity in the presence of a geographic and climatic heterogeneity over a large, spatial extent (Keatinge and Donaldson, 2001;Basu and Samet, 2002;Curriero et al., 2002;Yu et al., 2012). Separation of a large, contiguous area into smaller regions with similar prevailing climate conditions allows quantification of the effects of short-term exposure to extreme weather events and long-term adaptations to the prevailing climate conditions. ...
Article
Full-text available
Existing climate classification has not been designed for an efficient handling of public health scenarios. This work aims to design an objective spatial climate regionalization method for assessing health risks in response to extreme weather. Specific climate regions for the conterminous United States of America (USA) were defined using satellite remote sensing (RS) data and compared with the conventional Köppen-Geiger (KG) divisions. Using the nationwide database of hospitalisations among the elderly (≥65 year olds), we examined the utility of a RS-based climate regionalization to assess public health risk due to extreme weather, by comparing the rate of hospitalisations in response to thermal extremes across climatic regions. Satellite image composites from 2002-2012 were aggregated, masked and compiled into a multi-dimensional dataset. The conterminous USA was classified into 8 distinct regions using a stepwise regionalization approach to limit noise and collinearity (LKN), which exhibited a high degree of consistency with the KG regions and a well-defined regional delineation by annual and seasonal temperature and precipitation values. The most populous was a temperate wet region (10.9 million), while the highest rate of hospitalisations due to exposure to heat and cold (9.6 and 17.7 cases per 100,000 persons at risk, respectively) was observed in the relatively warm and humid south-eastern region. RS-based regionalization demonstrates strong potential for assessing the adverse effects of severe weather on human health and for decision support. Its utility in forecasting and mitigating these effects has to be further explored.
... The maximum effects were observed 3 days after the cold peak and effects lasted out to 40 days. Keatinge and Donaldson (2001) reported that a 1°C decrease in temperature was associated with 3% increase in total deaths over the next 24 days in greater London. Others have also reported strong associations between increased mortality and prolonged periods of cold weather in London (Eurowinter Group, 1997;Wilkinson et al, 1999). ...
Article
Community and voluntary sector contributors: Energy Action, Age Action, SVP, Irish Rural Link, Togher Social Club and Togher Retired Men's Club, Co. Wicklow Network for Older People, Older Women's Network, Age and Opportunity, ALONE, the Rural Transport Network (in particular Donegal and Cavan). Statutory contributors: Sustainable Energy Authority of Ireland, Dublin City Council, the Day Care Centre in St. John's Hospital Enniscorthy, Co. Wexford, Office for Older People, Wexford Local Development, Waterford County Council. Housing association contributors: NABCo, CART, Cluid, Irish Council for Social Housing, Oaklee, Respond. Other contributors (DIT): Jonathan Cullen, Dr Aidan O'Driscoll, Andy Maguire. The authors give special thanks to all who took the time to complete the questionnaire.
... Thus adjustments were made by including recent air temperature in the epidemiological models used, typically examining the effects of temperature-adjusted air pollution on the same day as the health outcome and/or variations that were measured up to a few days previously. However, several studies have suggested that effects on mortality of both cold temperature (Carder et al., 2005;Keatinge and Donaldson, 2001) and air pollution (Carder et al., 2008;Dominici et al., 2003;Goodman et al., 2004;Schwartz, 2000;Zeger et al., 1999) persist for considerably longer time periods. ...
... However, the majority of epidemiologic studies of air pollution include controls for temperature, thus to the extent these controls are successful, confounding between temperature and air pollution should be minimal. Keatinge and Donaldson (2001) found that cold-related mortality in London was not related to concurrent patterns in ambient sulfur dioxide, carbon monoxide, or smoke (surrogate for PM). ...
Article
Full-text available
In June 2005 Governor Arnold Schwarzenegger issued Executive Order S-3-05 that set greenhouse gas emission reduction targets for California, and directed the Secretary of the California Environmental Protection Agency to report to the governor and the State legislature by January 2006 and biannually thereafter on the impacts to California of global warming, including impacts to water supply, public health, agriculture, the coastline, and forestry, and to prepare and report on mitigation and adaptation plans to combat these impacts. This report is a part of the report to the governor and legislature, and focuses on public health impacts that have been associated with climate change. Considerable evidence suggests that average ambient temperature is increasing worldwide, that temperatures will continue to increase into the future, and that global warming will result in changes to many aspects of climate, including temperature, humidity, and precipitation (McMichael and Githeko, 2001). It is expected that California will experience changes in both temperature and precipitation under current trends. Many of the changes in climate projected for California could have ramifications for public health (McMichael and Githeko, 2001), and this document summarizes the impacts judged most likely to occur in California, based on a review of available peer-reviewed scientific literature and new modeling and statistical analyses. The impacts identified as most significant to public health in California include mortality and morbidity related to temperature, air pollution, vector and water-borne diseases, and wildfires. There is considerable complexity underlying the health of a population with many contributing factors including biological, ecological, social, political, and geographical. In addition, the relationship between climate change and changes in public health is difficult to predict for the most part, although more detailed information is available on temperature-related mortality and air pollution effects than the other endpoints discussed in this document. Consequently, these two topics are discussed in greater detail. Where possible, estimates of the magnitude and significance of these impacts are also discussed, along with possible adaptations that could reduce climate-related health impacts. In the context of this review, weather refers to meteorological conditions at a specific place and time over a relatively short time frame, such as up to a year or two. Climate, on the other hand, refers to the same meteorological conditions, but over a longer time frame, such as decades or centuries.
... Short-term changes in the concentration of air pollution may also heighten the risk of a cardiovascular event (Brook et al., 2004). Short-term pollution changes are influenced by weather conditions, however, and in several studies cardiovascular events were found to be linked more significantly with extreme temperature than air pollution (Keatinge and Donaldson, 2001;Basu and Samet, 2002;Filleul et al., 2006;Vaneckova et al., 2011). ...
Article
Full-text available
Several studies have examined the relationship of high and low air temperatures to cardiovascular mortality in the Czech Republic. Much less is understood about heat-/cold-related cardiovascular morbidity and possible regional differences. This paper compares the effects of warm and cold days on excess mortality and morbidity for cardiovascular diseases (CVDs) in the city of Prague and a rural region of southern Bohemia during 1994-2009. Population size and age structure are similar in the two regions. The results are evaluated for selected population groups (men and women). Excess mortality (number of deaths) and morbidity (number of hospital admissions) were determined as differences between observed and expected daily values, the latter being adjusted for long-term changes, annual and weekly cycles, and epidemics of influenza/acute respiratory infections. Generally higher relative excess CVD mortality on warm days than on cold days was identified in both regions. In contrast to mortality, weak excess CVD morbidity was observed for both warm and cold days. Different responses of individual CVDs to heat versus cold stress may be caused by the different nature of each CVD and different physiological processes induced by heat or cold stress. The slight differences between Prague and southern Bohemia in response to heat versus cold stress suggest the possible influence of environmental and socioeconomic factors such as the effects of urban heat island and exposure to air pollution, lifestyle differences, and divergence in population structure, which may result in differing vulnerability of urban versus rural population to temperature extremes.
... Other potential time-varying confounding and modifying factors, such as temperature and humidity, can also affect estimates of short-term effects of particles on respiratory mortality and morbidity differently in different seasons Ren and Tong 2008;Qian et al. 2012). Time series studies of the effects from both particles and weather conditions on mortality have identified the importance of adequate control for temperature and humidity when estimating air pollution effects (Mackenbach et al. 1993;Samet et al. , 1998Keatinge and Donaldson 2001;Goodman et al. 2004;Welty and Zeger 2005). Recently, two large collaborative air pollution projects which were conducted in Europe and USA have provided many new insights. ...
Article
Full-text available
Recent epidemiological and toxicological studies have shown associations between particulate matter and human health. However, the estimates of adverse health effects are inconsistent across many countries and areas. The stratification and interaction models were employed within the context of the generalized additive Poisson regression equation to examine the acute effects of fine particles on respiratory health and to explore the possible joint modification of temperature, humidity, and season in Beijing, China, for the period 2004-2009. The results revealed that the respiratory health damage threshold of the PM2.5 concentration was mainly within the range of 20-60 μg/m(3), and the adverse effect of excessively high PM2.5 concentration maintained a stable level. In the most serious case, an increase of 10 μg/m(3) PM2.5 results in an elevation of 4.60 % (95 % CI 3.84-4.60 %) and 4.48 % (95 % CI 3.53-5.41 %) with a lag of 3 days, values far higher than the average level of 0.69 % (95 % CI 0.54-0.85 %) and 1.32 % (95 % CI 1.02-1.61 %) for respiratory mortality and morbidity, respectively. There were strong seasonal patterns of adverse effects with the seasonal variation of temperature and humidity. The growth rates of respiratory mortality and morbidity were highest in winter. And, they increased 1.4 and 1.8 times in winter, greater than in the full year as PM2.5 increased 10 μg/m(3).
... Other weather conditions, i.e. specific variables such as humidity and rainfall, but also combinations of several meteorological variables (i.e. temperature, humidity, visibility, cloud cover, air pressure and wind speed) defined as ''synoptic air masses'', have been associated with increases in mortality and morbidity but specific evidence for respiratory causes is scarce and there is no clear evidence that these variables may have an independent effect apart from temperature [46][47][48][49][50][51][52]. ...
Article
Due to climate change, air pollution patterns are changing in several urbanized areas of the world, with a significant effect on respiratory health both independently and synergistically with weather conditions; climate scenarios show Europe as one of the most vulnerable regions. European studies on heat wave episodes have consistently shown a synergistic effect of air pollution and high temperatures, while the potential weather-air pollution interaction during wildfires and dust storms is unknown. Allergens patterns are also changing in response to climate change and air pollution can modify the allergenic potential of pollens especially in presence of specific weather conditions. The underlying mechanisms of all these interactions are not well known; the health consequences vary from decreases in lung function to allergic diseases, new onset of diseases, exacerbation of chronic respiratory diseases, and premature death. These multidimensional climate-pollution-allergen effects need to be taken into account in estimating both climate and air pollution-related respiratory effects in order to set up adequate policy and public health actions to face both the current and future climate and pollution challenges.
... Thus adjustments were made by including recent air temperature in the epidemiological models used, typically examining the effects of temperature-adjusted air pollution on the same day as the health outcome and/or variations that were measured up to a few days previously. However, several studies have suggested that effects on mortality of both cold temperature (Carder et al., 2005; Keatinge and Donaldson, 2001) and air pollution (Carder et al., 2008; Dominici et al., 2003; Goodman et al., 2004; Schwartz, 2000; Zeger et al., 1999) persist for considerably longer time periods. We have found some evidence of interaction between (cold) temperature and particulate matter air pollution in their effect on all-cause and respiratory mortality (Carder et al., 2008 ). ...
Article
Objectives: To examine associations between short/medium-term variations in black smoke air pollution and mortality in the population of Glasgow and the adjacent towns of Renfrew and Paisley over a 25-year period at different time lags (0-30 days). Methods: Generalised linear (Poisson) models were used to investigate the relationship between lagged black smoke concentrations and daily mortality, with allowance for confounding by cold temperature, between 1974 and 1998. Results: When a range of lag periods were investigated significant associations were noted between temperature-adjusted black smoke exposure and all-cause mortality at lag periods of 13-18 and 19-24 days, and respiratory mortality at lag periods of 1-6, 7-12, and 13-18 days. Significant associations between cardiovascular mortality and temperature-adjusted black smoke were not observed. After adjusting for the effects of temperature a 10 μgm(-3) increase in black smoke concentration on a given day was associated with a 0.9% [95% Confidence Interval (CI): 0.3-1.5%] increase in all cause mortality and a 3.1% [95% CI: 1.4-4.9%] increase in respiratory mortality over the ensuing 30-day period. In contrast for a 10 μgm(-3) increase in black smoke concentration over 0-3 day lag period, the temperature adjusted exposure mortality associations were substantially lower (0.2% [95% CI: -0.0-0.4%] and 0.3% [95% CI: -0.2-0.8%] increases for all-cause and respiratory mortality respectively). Conclusions: This study has provided evidence of association between black smoke exposure and mortality at longer lag periods than have been investigated in the majority of time series analyses.
... Vehicle emissions are respon sible for a substantial share of air pollution concentrations in this area, as in other areas in Seoul (Kim and Guldmann 2011). We also collected temperature and rainfall values from the Korea Meteorological Administration (2012) to adjust for these environmen tal confounders in the model (Keatinge and Donaldson 2001). ...
Article
Full-text available
Although the effect of air pollution on various diseases has been extensively investigated, few studies have examined its effect on depression. We investigated the effect of air pollution on symptoms of depression in an elderly population. We enrolled 537 participants in the study who regularly visited a community center for the elderly located in Seoul, Korea. The Korean version of the Geriatric Depression Scale-Short Form (SGDS-K) was used to evaluate depressive symptomatology during a 3-year follow-up study. We associated ambient air pollutants with SGDS-K results using generalized estimating equations (GEE). We also conducted a factor analysis with items on the SGDS-K to determine which symptoms were associated with air pollution. SGDS-K scores were positively associated with interquartile range (IQR) increases in the 3-day moving average concentration of particulate matter with an aerodynamic diameter ≤ 10 μm (PM10) [17.0% increase in SGDS-K score, 95% confidence interval (CI): 4.9%, 30.5%], the 0-7 day moving average of nitrogen dioxide [NO2; 32.8% (95% CI: 12.6%, 56.6%)], and the 3-day moving average of ozone [O3; 43.7% (95% CI: 11.5%, 85.2%)]. For these three pollutants, factor analysis showed that air pollution was more strongly associated with emotional symptoms such as feeling happy and satisfied than with somatic or affective symptoms. Our study suggests that increases in PM10, NO2, and O3 may increase depressive symptoms among the elderly. Of the symptoms evaluated, ambient air pollution was most strongly associated with emotional symptoms.
... The effects of cold temperatures on mortality can last for days, with the greatest association sometimes observed on the same day (28), and lasting up to 24 days after the cold weather. Air pollution (29,30) can modify the effect of cold weather with increasing associations between cold and mortality with higher pollution. ...
Article
Winter weather patterns are anticipated to become more variable with increasing average global temperatures. Research shows that excess morbidity and mortality occurs during cold weather periods. We critically reviewed evidence relating temperature variability, health outcomes, and adaptation strategies to cold weather. Health outcomes included cardiovascular-, respiratory-, cerebrovascular-, and all-cause morbidity and mortality. Individual and contextual risk factors were assessed to highlight associations between individual- and neighborhood-level characteristics that contribute to a person's vulnerability to variability in cold weather events. Epidemiologic studies indicate that the populations most vulnerable to variations in cold winter weather are the elderly, rural and, generally, populations living in moderate winter climates. Fortunately, cold-related morbidity and mortality are preventable and strategies exist for protecting populations from these adverse health outcomes. We present a range of adaptation strategies that can be implemented at the individual, building, and neighborhood level to protect vulnerable populations from cold-related morbidity and mortality. The existing research justifies the need for increased outreach to individuals and communities for education on protective adaptations in cold weather. We propose that future climate change adaptation research couple building energy and thermal comfort models with epidemiological data to evaluate and quantify the impacts of adaptation strategies.
... For example, Sartor et al. (1995) hypothesized that most of excess deaths during the heat wave of 1994 in Belgium were likely attributable to elevated levels of O 3 (instead of temperature). Such multicollinearity, along with using data outside the linear range of dependencies, has caused errors in the determination of risks of individual pollutants to human health (Keatinge and Donaldson 2001). ...
Article
Full-text available
The objectives of this study were (1) to evaluate how acute mortality responds to changes in particulate and ozone (O(3)) pollution levels, (2) to identify vulnerable population groups by age and cause of death, and (3) to address the problem of interaction between the effects of O(3) and particulate pollution. Time-series of daily mortality counts, air pollution, and air temperature were obtained for the city of Moscow during a 3-year period (2003-2005). To estimate the pollution-mortality relationships, we used a log-linear model that controlled for potential confounding by daily air temperature and longer term trends. The effects of 10 mug/m(3) increases in daily average measures of particulate matter </=10 mum in aerodynamic diameter (PM(10)) and O(3) were, respectively, (1) a 0.33% [95% confidence interval (CI) 0.09-0.57] and 1.09% (95% CI 0.71-1.47) increase in all-cause non-accidental mortality in Moscow; (2) a 0.66% (0.30-1.02) and 1.61% (1.01-2.21) increase in mortality from ischemic heart disease; (3) a 0.48% (0.02-0.94) and 1.28% (0.54-2.02) increase in mortality from cerebrovascular diseases. In the age group >75 years, mortality increments were consistently higher, typically by factor of 1.2 - 1.5, depending upon the cause of death. PM(10)-mortality relationships were significantly modified by O(3) levels. On the days with O(3) concentrations above the 90th percentile, PM(10) risk for all-cause mortality was threefold greater and PM(10) risk for cerebrovascular disease mortality was fourfold greater than the unadjusted risk estimate.
... The effects of cold temperatures may occur over prolonged periods of time, in some cases up to a few weeks (Keatinge and Donaldson, 2001;Carder et al., 2005). However, the CWI that we used represented the current day's minimum temperature fluctuation relative to the previous day's minimum temperature. ...
Article
In South Korea, the mortality increases with temperature above a certain threshold during the warm season. In contrast, despite the common burden of cold weather, little is known about the effects of low temperatures on mortality. We evaluated the relationship between low temperatures and mortality in winter (December-February) in Seoul, South Korea, from 1994 to 2006. Data were obtained from government agencies. After adjusting for trends in time, day of the week, holidays, and relative humidity, we explored the associations between mortality and various cold indicators of winter in Seoul, South Korea. First, we fitted nonparametric smoothing regression models to check the shape of associations and then fitted threshold models (including two different slopes in a model) to estimate the thresholds and the effects of low temperatures using the Akaike Information Criterion (AIC). The graphical associations between cardiorespiratory, cardiovascular, and all causes of mortality and the cold wave index (CWI=T(min, previous day)-T(min, current day)) were observed. We confirmed the threshold according to a lag structure and after that, estimated the effects of CWI below the threshold, respectively. The effects of the daytime CWI lagged by 0-2 days were the strongest among those of the daytime CWI lagged by 0-6 days. The most significant mortality outcomes were cardiovascular-related. Although we could not consider respiratory-related mortality, the effect of CWI on cardiovascular-related mortality below a certain threshold was greater than cardiorespiratory-related or all cause-related mortality. In addition, the association between mortality and CWI was more immediate and vulnerable in an elderly subgroup (> or =65 years old) than in a younger subgroup (0-64 years old). Our results suggest that public health programs should be considered to alleviate not only the effect of sudden change in winter temperature on mortality.
... been associated with increases in daily mortality (Keating and Donaldson 1995; Eurowinter Group 1997), and with the number of hospital admissions for diverse illnesses, respiratory disease (Buff et al. 1995; Donaldson et al. 1999; Eccles 2002) and, recently, cardiovascular diseases (Eurowinter group 1997; Peckova et al. 1999; Allegra et al. 2002). Keating and Donaldson (2001) reported that cold weather affects respiratory mortality in winter. Gordon (2003) postulates that annual changes in temperature and acclimatization to environmental conditions may influence physiological responses to toxic chemicals. Stout and Crawford (1991) showed that plasma, cholesterol, plasma fibrinogen, blood pressure and red and ...
Article
Full-text available
The objective of this study was to assess the relationship between diurnal temperature range (DTR) and emergency room (ER) admissions for chronic obstructive pulmonary disease (COPD) in an ER in Taichung City, Taiwan. The design was a longitudinal study in which DTR was related to COPD admissions to the ER of the city's largest hospital. Daily ER admissions for COPD and ambient temperature were collected from 1 January 2001 to 31 December 2002. There was a significant negative association between the average daily temperature and ER admissions for COPD (r=-0.95). However, a significant positive association between DTR and COPD admissions was found (r=0.90). Using the Poisson regression model after adjusting for the effects of air pollutants and the day of the week, COPD admissions to the ER increased by 14% when DTR was over 9.6 degrees C. COPD patients must be made aware of the increased risk posed by large DTR. Hospitals and ERs should take into account the increased demand of specific facilities during periods of large temperature variations.
... A known relationship exists between temperature and mortality. [1][2][3][4][5] In general increased death rates occur principally in the elderly 6 and the relationship is considered to take the form of a 'V' or a 'U' shape, with the lowest death rates occurring on days of moderate temperature and highest rates at either end of the temperature range. 7,8 In the UK a 2% increase in mortality has been estimated for every one degree fall in temperature from 18°C. 9 Most of the excess mortality is due to respiratory, cardiac and cerebrovascular disease. ...
Article
Full-text available
The relationships between cold temperatures and cardio-respiratory mortality in the elderly are well documented. We wished to determine whether similar relationships exist with consultations in the primary care setting and to assess the lag time at which the effects were observed. Generalized additive models were used to regress time-series of daily numbers of general practitioner (GP) consultations by the elderly against temperature, after control for possible confounders and adjustment for overdispersion and serial correlation. Consultation data were available from between 38 452 and 42 772 registered patients aged >or=65 years from 45-47 London practices contributing to the General Practice Research Database between January 1992 and September 1995. There was little relationship between consultations for respiratory disease and mean temperature on the same day as the day of consultation. However, a strong association was apparent with temperature levels up to 15 days previously, with an increase in consultations being observed particularly as temperatures drop below 5 degrees C. Every 1 degrees C decrease in mean temperatures below 5 degrees C was associated with a 10.5% (95% CI: 7.6%, 13.4%) increase in all respiratory consultations. No relationship was observed between cold temperatures and GP consultations for cardiovascular disease. Our study suggests a delayed effect of a drop in temperature on consultations for respiratory disease in the primary care setting. Information such as this could be used to help prepare practices to anticipate increases in respiratory consultation rates associated with low temperatures.
... Since lagged data gave less steep mortality/temperature relationships than unlagged data, unlagged data were used throughout. We made no allowance for atmospheric pollution, as the effects of this are uncertain (Keatinge and Donaldson, 2001); any effects of smoke or ozone on mortality do not appear to interact with high temperature (Katsouyanni et al., 1993; Smoyer et al., 2000). Single regressions of annual variables by year, to assess the significance of simple changes in these with time for all people aged 55 and over in each region, are given in Figs. 2 and 3. Multiple regression analysis was then performed to allow for the effects of the changing age and sex structure of the population (Table 2). ...
Article
Three climatically diverse regions were studied to determine the impact of temperature change on heat-related mortality from 1971 to 1997. Median regressions showed that May-August temperatures in North Carolina rose by 1.0 degrees C (95% CL 0.0-2.0 degrees C) from 23.5 degrees C (74.3 degrees F), were unchanged in South Finland at 13.5 degrees C (56.3 degrees F), and rose in Southeast England 2.1 degrees C (0.3-4.0 degrees C) from 14.9 degrees C (58.8 degrees F). After determining for each region the daily temperature (as a 3 degrees C band) at which the mortality was the lowest, annual heat-related mortality was obtained as excess mortality per million at temperatures above this. Annual heat-related mortality per million (among the population at risk, aged 55+) fell in North Carolina by 212 (59-365) from 228 (140-317) to only 16 (not significant, NS); fell in South Finland by 282 (66-500) from 382 (257-507) to 99 (NS); and fell in Southeast England by 2.4 (NS) from 111 (41-180) to 108 (41-176). The falls in North Carolina and South Finland remained significant after allowances were made for changes in age, sex, and baseline mortality. Increased air conditioning probably explains the virtual disappearance of heat-related mortality in the hottest region, North Carolina, despite warmer summers. Other lifestyle changes associated with increasing prosperity probably explain the favorable trends in the cooler regions.
Article
Full-text available
Rationale Extremes of temperature and humidity are associated with adverse respiratory symptoms, reduced lung function, and increased exacerbations among individuals living with chronic obstructive pulmonary disease (COPD). Objectives To describe the reported effects of temperature and humidity extremes on the health outcomes, health status and physical activity (PA) in individuals living with COPD. Methods A cross-sectional self-reported survey collected the effects on health status (COPD Assessment Test [CAT]), PA, and health outcomes in 1) moderate/ideal (14 to 21°C, 30 to 50% relative humidity [RH]), 2) hot and humid (≥ 25°C, > 50% RH) and 3) cold and dry (≤ 5°C, < 30% RH) weather conditions. Participants were ≥ 40 years old with COPD or related chronic respiratory diseases (e.g., asthma, sleep apnea, interstitial lung disease, lung cancer) and residing in Canada for ≥ 1 year. Negative responders to weather extremes were a priori defined as having a change of ≥ 2 points in the CAT. Main Results Thirty-six participants responded; the mean age (SD) was 65 (11) years, and 23 (64%) were females. Compared to ideal conditions, 23 (66%) and 24 (69%) were negatively affected by cold/dry and hot/humid weather, respectively. Health status was significantly lower, and PA amount and difficulty level were reduced in hot/humid and cold/dry conditions compared with ideal conditions. The number of exacerbations in hot/humid was significantly higher compared to ideal conditions. Conclusions More participants were negatively affected by extremes of weather: health status worsened, PA decreased, and frequency of exacerbations was higher compared to ideal. Future prospective studies should directly and objectively investigate different combinations of extreme temperature and humidity levels on symptoms and PA to understand their long-term health outcomes.
Chapter
National data repositories, such as census, surveys, clinical records, and surveillance systems, provide incredibly valuable information to establish links between health outcomes and environmental exposures, as well as to guide national, local, and global environmental and health policies to achieve the Sustainable Development Goals (SDGs). The SDGs, under the 2030 Agenda for Sustainable Development, call for improving health and education, reducing inequality, increasing economic growth, and creating sustainable environmental policies and practices. Using the SDGs as a global model, environmental health research can be focused on regions that have not yet met the goals. Modern geospatial tools enable a better understanding of spatiotemporal patterns of environmentally driven, climate-sensitive, and often preventable infections. Current research highlights the untapped potential of national repositories of medical claims, laboratory-confirmed surveillance records, and census data to quantify and predict the impact of environmental exposure and the complexity of interrelationships between spatiotemporal clustering of infections and water quality and quantity, extreme weather, and climate change. A systematic approach to quantify and depict an outcome, exposure, and the relationship between them, along with relevant uncertainties, in a given location at a given time, is essential for effective prevention. To build national and global geospatial capacities, accurate information at refined spatial and temporal scales is needed. However, the continuous monitoring of health and environmental data, especially in resource-poor settings of low-income countries, is prohibitively expensive and prone to underreporting and biases. Even in data-rich, high-income environments, advanced surveillance and public health records contain inaccuracies and inconsistencies that can cause costly errors of displacing or not accounting for ever-changing exposures. Aiming to meet the SDGs, many countries are strengthening their efforts to establish robust national data infrastructure. In this chapter, we illustrate such efforts and highlight ongoing challenges that arise in compiling the essential demographic, socioeconomic, environmental, and health records in Ghana to explore spatiotemporal patterns in climate-sensitive disease caused by Schistosoma haematobium and diarrheal infections. We recommend further investment in building a robust data infrastructure by technological leapfrogging with the support of novel geospatial tools.
Article
Full-text available
Emergency risk communication (ERC) programs that activate when the ambient temperature is expected to cross certain extreme thresholds are widely used to manage relevant public health risks. In practice, however, the effectiveness of these thresholds has rarely been examined. The goal of this study is to test if the activation criteria based on extreme temperature thresholds, both cold and heat, capture elevated health risks for all‐cause and cause‐specific mortality and morbidity in the Minneapolis‐St. Paul Metropolitan Area. A distributed lag nonlinear model (DLNM) combined with a quasi‐Poisson generalized linear model is used to derive the exposure–response functions between daily maximum heat index and mortality (1998–2014) and morbidity (emergency department visits; 2007–2014). Specific causes considered include cardiovascular, respiratory, renal diseases, and diabetes. Six extreme temperature thresholds, corresponding to 1st–3rd and 97th–99th percentiles of local exposure history, are examined. All six extreme temperature thresholds capture significantly increased relative risks for all‐cause mortality and morbidity. However, the cause‐specific analyses reveal heterogeneity. Extreme cold thresholds capture increased mortality and morbidity risks for cardiovascular and respiratory diseases and extreme heat thresholds for renal disease. Percentile‐based extreme temperature thresholds are appropriate for initiating ERC targeting the general population. Tailoring ERC by specific causes may protect some but not all individuals with health conditions exacerbated by hazardous ambient temperature exposure.
Article
This chapter examines the relationship between ambient temperature and mortality or disease occurrence in adults, in particular from cardiovascular diseases. Epidemiological investigation provides evidence for a relationship between ambient temperature and mortality, particularly from cardiovascular and respiratory causes. The association is consistent across different study designs and methodologies, countries worldwide, and varying time periods, despite the use of routine data and their inherent inaccuracies. Whilst both hot and cold temperatures are associated with increased deaths, the effects of hot temperatures appear to reflect mainly short-term mortality displacement, whilst cold temperatures appear to have prolonged effects on mortality.
Article
Full-text available
This paper aims to define atmospheric pathways related with the occurrence of daily winter low temperature episodes (LTE) in England, for the 26-year period 1974-1999, and to reveal possible associations with increased mortality rates. For this purpose, backward air mass trajectories, corresponding to LTE in five regions of England, were deployed. A statistically significant increase in mortality levels, at the 0.05 level, was found for LTE, compared to non-LTE days across all five regions. Seven categories of atmospheric trajectory patterns associated with LTE were identified: East, Local, West, North Atlantic, Arctic, South West and Scandinavian. Consideration of the link between air mass trajectory patterns and mortality levels by region revealed a possible west-to-east split in the nature of air masses connected with elevated mortality. Specifically, for the West Midlands and North West regions, relatively warm winter weather conditions from the west, most likely associated with the eastward progression of low pressure systems, are allied with the highest daily average mortality counts, whereas, for the North East, Humberside/York and South East regions, cold continental air advection from northern or eastern Europe, that lasts for several days and linked with either a blocking pattern over the western margins of Europe or an intense high pressure anomaly over eastern or northern Europe, appears important in mortality terms. This finding confirms that winter weather health associations are complex, such that climate setting and air mass climatology need to be taken into account when considering climate and health relationships.
Article
Full-text available
Although plausible pathophysiological mechanisms link air pollution to arrhythmogenesis, among them altered autonomic tone, repolarization abnormalities, oxidative stress, myocardial ischemia, and increased intracardiac pressure (Link and Dockery 2010), definitive conclusions have not been reached as yet. Langrish et al. (2014) analyzed 13 double-blind randomized crossover studies and found no significant risk of arrhythmia attributable to acute controlled exposure to air pollutants. Three issues related to meteorological factors probably either confound or modify the short-term association between air pollution and cardiac arrhythmia. First, several meteorological elements, including air temperature, atmospheric pressure, relative air moisture, and wind speed and direction, also are implicated in triggering ventricular (Culic et al. 2004, 2005) and supraventricular (Culic et al. 2012, 2013) arrhythmias independent of physical and emotional stress. In the short term, those meteorological factors may facilitate arrhythmias in susceptible patients by increasing circulatory load and thromboinflammatory processes (Culic 2014). Second, these same meteorological elements substantially influence concentrations of sulfur dioxide, carbon monoxide, nitrogen dioxide, ozone, and suspended particulate matter (Bertaccini et al. 2012; Ilten and Selici 2008; Ito et al. 2007). In addition, the greatest ozone production and pollution results from stable, dry, hot weather with high atmospheric pressure and low wind (Vanos et al. 2014). Air pollution may increase human vulnerability to the effects of temperature, and temperature extremes, in turn, influence population vulnerability to air pollution (Burkart et al. 2013; Ren et al. 2006). Vanos et al. (2014) reported that cardiovascular and respiratory mortality due to short-term exposure to gaseous air pollutants was significantly modified by weather types and season. Alberdi et al. (1998) reported that both relative air moisture and air temperature are strongly related to daily mortality even after controlling for air pollution and influenza. Keatinge and Donaldson (2001) suggested that prolonged cold weather with less wind and rain may produce false associations between mortality and certain air pollutants. Finally, strong mutual interrelations exist among the above-mentioned meteorological elements. Alberdi et al. (1998) pointed out the strong inverse association they observed between relative air moisture and air temperature as an important problem for regression analysis. Langrish et al. (2014) caution against definitive acceptance of air pollution as an independent trigger of cardiac arrhythmias. However, the studies included in their analysis had no data on meteorological factors. It is likely that interactive effects among air pollutants and meteorological elements bias each other’s association with arrhythmias and other acute cardiac events. Therefore, further research of the health effects of atmospheric factors should continue in order to identify potentially harmful influences for the population as whole as well as for its vulnerable subgroups.
Article
For all climatic regions, mortality due to cold exceeds mortality due to heat. A separate line of research indicates that season of birth predicts lifespan after age 50. This and other literature implies the hypothesis that ambient temperature during gestation may influence cold-related adult mortality. We use data on over 13,500 Swedes from the Uppsala Birth Cohort Study to test whether cold-related mortality in adulthood varies positively with unusually benign ambient temperature during gestation. We linked daily thermometer temperatures in Uppsala, Sweden (1915-2002) to subjects beginning at their estimated date of conception and ending at death or the end of follow-up. We specified a Cox proportional hazards model with time-dependent covariates to analyze the two leading causes of cold-related death in adulthood: ischemic heart disease (IHD) and stroke. Over 540,450 person-years, 1313 IHD and 406 stroke deaths occurred. For a one standard deviation increase in our measure of warm temperatures during gestation, we observe an increased hazard ratio of 1.16 for cold-related IHD death (95% confidence interval: 1.03-1.29). We, however, observe no relation for cold-related stroke mortality. Additional analyses show that birthweight percentile and/or gestational age do not mediate discovered findings. The IHD results indicate that ambient temperature during gestation-independent of birth month-modifies the relation between cold and adult mortality. We encourage longitudinal studies of the adult sequelae of ambient temperature during gestation among populations not sufficiently sheltered from heat or cold waves.
Article
Heat waves and air pollution are both associated with increased mortality. Their joint effects are less well understood. We explored the role of air pollution in modifying the effects of heat waves on mortality, within the EuroHEAT project. Daily mortality, meteorologic, and air pollution data from nine European cities for the years 1990-2004 were assembled. We defined heat waves by taking both intensity and duration into account. The city-specific effects of heat wave episodes were estimated using generalized estimating equation models, adjusting for potential confounders with and without inclusion of air pollutants (particles, ozone, nitrogen dioxide, sulphur dioxide, carbon monoxide). To investigate effect modification, we introduced an interaction term between heat waves and each single pollutant in the models. Random effects meta-analysis was used to summarize the city-specific results. The increase in the number of daily deaths during heat wave episodes was 54% higher on high ozone days compared with low, among people age 75-84 years. The heat wave effect on high PM10 days was increased by 36% and 106% in the 75-84 year and 85+ year age groups, respectively. A similar pattern was observed for effects on cardiovascular mortality. Effect modification was less evident for respiratory mortality, although the heat wave effect itself was greater for this cause of death. The heat wave effect was smaller (15-30%) after adjustment for ozone or PM10. The heat wave effect on mortality was larger during high ozone or high PM10 days. When assessing the effect of heat waves on mortality, lack of adjustment for ozone and especially PM10 overestimates effect parameters. This bias has implications for public health policy.
Article
In this paper, the authors systematize the results of their original investigations into quantitative indicators of interactions between indicators of air temperature, air-pollution, and population mortality. The application of the time series method made it possible to identify the quantitative parameters of the impact made by temperature waves on mortality rates in Moscow (2000—2006) and in northern cities, such as Archangelsk, Murmansk, Magadan, and Yakutsk (1999–2007).
Chapter
The present chapter is intended to provide an overview of cold stress and strain not only on workers in cold workplaces, but also on people in general exposed to cold climate. Human adaptation to cold can be either acquired or inherited and occurs through acclimatization. The pattern of cold adaptation is dependent on the type (air, water) and intensity (continuous, intermittent) of the cold exposure. It has been reported that cold exposure and cooling can have profound effects on physical and cognitive performance. The majority of scientific reports related to health consequences of cold weather are on acute health changes. The study finds that total mortality among most populations is highest in winter and lowest in summer. Regulations or standards defining acceptable cold stress situations rely on one or a combination of approaches to control cold stress. Most prevalent national or international exposure guidelines have been provided comprehensively. Keywords: clothing; frostbite; hand-arm vibration syndrome; hypothermia; solar radiation; wind chill temperature; cold mortality; cold morbidity
Article
This article is devoted to the analysis of the relationship between the health status of an urban population and meteorological variables. The analysis considers daily number of hospital admissions, not due to surgery, regarding the population resident in the Municipality of Udine, aged 75 and over. Hourly records on temperature, humidity, rain, atmospheric pressure, solar radiation, wind velocity and direction recorded at an observation site located near the center of Udine are considered. The study also considers hourly measures of pollutant concentrations collected by six monitoring stations. All data are relative to the summer periods of years 1995–2003. Generalized additive models (GAM) are used in which the response variable is the number of hospital admissions and is assumed to be distributed as a Poisson whose rate varies as a possibly non-linear function of the meteorological variables and variables allowing for calendar effects and pollutant concentrations. The subsequent part of the analysis explores the distribution of temperature conditional on the number of daily admissions through quantile regression. A non-linear (N-shaped) relationship between hospital admissions and temperature is estimated; temperature at 07:00 is selected as a covariate, revealing that nighttime temperature is more relevant than daytime. The quantile regression analysis points out, as expected, that the distribution of temperature on days with more admissions has higher q-quantiles with q near unity, while a clear-cut conclusion is not reached for q quantiles with q near 0. Copyright © 2005 John Wiley & Sons, Ltd.
Article
Because the health effects of climate change are likely to be significant and far-reaching, a key component of climate change adaptation will be our public health infrastructure. Perhaps counter-intuitively, recent emphasis in public health law on preparedness for extraordinary events may be to the detriment of our ability to cope with the health impacts of climate change. While existing emergency preparedness law will necessarily be an important backdrop for health-focused climate change adaptation efforts (especially with regard to natural disasters and infectious disease outbreaks), the focus on emergency preparedness in recent years does not necessarily situate us well for handling the substantial, but slowly emerging, intensification of more routine health threats that we expect to see as an impact of climate change. This paper examines the likely demands of climate change on public health infrastructure, law, and policy and argues that the adaptation response to climate change has the potential to improve public health infrastructure in ways that will better position us to handle routine needs as they intensify and to move public health law and policy toward an approach that emphasizes “resilience” rather than “preparedness.”Three case studies are used to illustrate the current public health law and policy response to the types of health threats that we are likely to see in the U.S. as a consequence of climate change: (1) the incompatibility of the strategic national stockpile of pharmaceutical and medical supplies with the needs of disaster victims following Hurricane Katrina; (2) privacy-based barriers to public health surveillance programs seeking to track trends in pediatric asthma; and (3) conflicts over the use of pesticides for vector control to fight West Nile Virus in the United States. Upon delving more deeply into these three examples, a picture emerges of the ways in which climate change weighs in on some of the key concerns of public health and public health law. Because the health threats associated with climate change are likely to exacerbate underlying health disparities (in that they are particularly concerning for vulnerable subpopulations such as the poor, city-dwellers, the elderly, and those who suffer from chronic health conditions), climate change adaptation will raise issues of health equity and put pressure on the traditional divide between public and private responsibility for health. Because the health impacts of climate change are predominantly local in nature but are likely to overwhelm local resources, climate change adaptation will require us to revisit jurisdictional issues regarding the funding and control of health programs to emphasize adequate support for community-based responses. Responding to severe health threats that are not immediately urgent, will require new ways of thinking about the balance between individual rights and community needs that go beyond reliance on the concept of a public health “emergency” to override more deliberative processes. Finally, because some measures that might be used to adapt to the impacts of climate change will pose potential risks of their own, adaptation planning will raise the challenge of informing public choices about risk in the context of complex risk-risk trade-offs. I argue that, taken together, these considerations have the potential to move public health law toward a new approach that emphasizes “resilience” rather than “preparedness.” This approach would be deliberative, equity-driven, and community-based, and would seek to balance respect for lay values with correction of facts regarding the various risks involved.
Article
Full-text available
The effects of the anomalously warm European summer of 2003 highlighted the importance of understanding the relationship between elevated atmospheric temperature and human mortality. This review is an extension of the brief evidence examining this relationship provided in the IPCC’s Assessment Reports. A comprehensive and critical review of the literature is presented, which highlights avenues for further research, and the respective merits and limitations of the methods used to analyse the relationships. In contrast to previous reviews that concentrate on the epidemiological evidence, this review acknowledges the inter-disciplinary nature of the topic and examines the evidence presented in epidemiological, environmental health, and climatological journals. As such, present temperature–mortality relationships are reviewed, followed by a discussion of how these are likely to change under climate change scenarios. The importance of uncertainty, and methods to include it in future work, are also considered.
Article
To investigate whether deprivation index modifies the acute effect of black smoke on cardiorespiratory mortality. Generalised linear Poisson regression models were used to investigate whether deprivation index (as measured by the Carstairs deprivation index) modified the acute effect of black smoke on mortality in two largest Scottish cities (Glasgow and Edinburgh) between January 1981 and December 2001. Lag periods of up to 1 month were assumed for the effects of black smoke. Deprivation index significantly modified the effect of black smoke on mortality, with black smoke effects generally increasing as level of deprivation increased. The interaction coefficient from a parametric model assuming a linear interaction between black smoke (microg/m(-3)) and deprivation in their effect on mortality--equivalent to a test of 'linear trend' across Carstairs categories--was significant for all mortality outcomes. In a model where black smoke effects were estimated independently for each deprivation category, the estimated increase in respiratory mortality over the ensuing 1-month period associated with a 10 microg/m(3) increase in the mean black smoke concentration was 8.0% (95% CI 5.1 to 10.9) for subjects residing in the 'most' deprived category (Carstairs category 7) compared to 3.7% (95% CI -0.7 to 8.4) for subjects residing in the 'least' deprived category (Carstairs category 1). The results suggest a stronger effect of black smoke on mortality among people living in more deprived areas. The effect was greatest for respiratory mortality, although significant trends were also seen for other groups. If corroborated, these findings could have important public health implications.
Article
Seasonal variations in the incidence of cardiovascular disease, mainly characterized by a winter peak, have been consistently reported. Some evidence now also exists on potential seasonal variations in the incidence of venous thromboembolism (VTE). Of interest, seasonal variability in the incidence of deep vein thrombosis and fatal and nonfatal pulmonary embolism appears to differ; however, the results of available studies are not unequivocal. This review will briefly summarize current evidence in this area. Recent studies indicate a seasonal variability in the incidence of VTE, with a pattern that is independent of sex, age, type of event, or underlying risk factors. Usually, these studies found a higher VTE incidence during the winter months and a lower incidence in the summer months. The exact mechanism of this variability is not completely understood, but it may be at least in part explained by changes in coagulation factor levels. Confirmation of these findings and a better understanding of underlying mechanisms could help physicians to identify patients or periods with increased risk of VTE in order to further improve current prophylactic strategies.
Article
We evaluated temperature-related morbidity and mortality for the 2007 U.S. national assessment on impacts of climate change and variability on human health. We assessed literature published since the 2000 national assessment, evaluating epidemiologic studies, surveys, and studies projecting future impacts. Under current climate change projections, heat waves and hot weather are likely to increase in frequency, with the overall temperature distribution shifting away from the colder extremes. Vulnerable subgroups include communities in the northeastern and Midwestern U.S.; urban populations, the poor, the elderly, children, and those with impaired health or limited mobility. Temperature extremes and variability will remain important determinants of health in the United States under climate change. Research needs include estimating exposure to temperature extremes; studying nonfatal temperature-related illness; uniform criteria for reporting heat-related health outcomes; and improving effectiveness of urban heat island reduction and extreme weather response plans.
Article
A comprehensive, systematic synthesis was conducted of daily time-series studies of air pollution and mortality from around the world. Estimates of effect sizes were extracted from 109 studies, from single- and multipollutant models, and by cause of death, age, and season. Random effects pooled estimates of excess all-cause mortality (single-pollutant models) associated with a change in pollutant concentration equal to the mean value among a representative group of cities were 2.0% (95% CI 1.5-2.4%) per 31.3 microg/m3 particulate matter (PM) of median diameter < or = 10 microm (PM10); 1.7% (1.2-2.2%) per 1.1 ppm CO; 2.8% (2.1-3.5%) per 24.0 ppb NO2; 1.6% (1.1-2.0%) per 31.2 ppb O3; and 0.9% (0.7-1.2%) per 9.4 ppb SO2 (daily maximum concentration for O3, daily average for others). Effect sizes were generally reduced in multipollutant models, but remained significantly different from zero for PM10 and SO2. Larger effect sizes were observed for respiratory mortality for all pollutants except O3. Heterogeneity among studies was partially accounted for by differences in variability of pollutant concentrations, and results were robust to alternative approaches to selecting estimates from the pool of available candidates. This synthesis leaves little doubt that acute air pollution exposure is a significant contributor to mortality.
Article
Full-text available
The higher occurrence of cardiovascular diseases in winter is well known, and several explanatory mechanisms have been suggested based on increased blood pressure, haematological changes and respiratory infections. Most investigations have used ecological data such as daily temperatures recorded at weather stations and mortality in the general population. Cause-specific mortality is the outcome measure most commonly used. Local myocardial infarction community registers would offer an ideal database, but may suffer from inadequate statistical power. Hospital discharge records, linked with out-of-hospital deaths, provide a powerful tool for detecting even weak effects of temperature. The association of coronary heart disease and temperature is usually U-shaped, mortality being lowest within the range 15-20 degrees C and higher on both sides of this. The increase in mortality on the colder side is in the region of 1% per 1 degree C fall in temperature, but the increase on the warmer side may be very steep. The exact location of the minimum temperature and the magnitude of the effect can vary between countries. In Finland the winter excess mortality from coronary heart disease has been levelling off during recent decades, but it still represents approximately 6% of annual deaths due to this condition.
Article
In the 1970s scientific research focussed for the first time on dramatic rises in mortality every winter, and on smaller rises in unusually hot weather. Following the recent decline in influenza epidemics, approximately half of excess winter deaths are due to coronary thrombosis. These peak about two days after the peak of a cold spell. Approximately half the remaining winter deaths are caused by respiratory disease, and these peak about 12 days after peak cold. The rapid coronary deaths are due mainly to haemoconcentration resulting from fluid shifts during cold exposure; some later coronary deaths are secondary to respiratory disease. Heat related deaths often result from haemoconcentration resulting from loss of salt and water in sweat. With the possible exception of some tropical countries, global warming can be expected to reduce cold related deaths more than it increases the rarer heat related deaths, but statistics on populations in different climates suggest that, given time, people will adjust to global warming with little change in either mortality. Some measures may be needed to control insect borne diseases during global warming, but current indications are that cold will remain the main environmental cause of illness and death. Air pollution in cities may also still be causing some deaths, but these are hard to differentiate from the more numerous deaths due to associated cold weather, and clear identification of pollution deaths may need more extensive data than is currently available.
Article
Full-text available
We investigated the impact of environmental temperature on mortality in São Paulo, Brazil, and examined differences in the temperature-mortality relationship with respect to cause, age group, and socioeconomic position (SEP). Generalized additive Poisson regression models adjusted for non-temperature related seasonal factors (including air pollution) were used to analyse daily mortality counts for selected causes from 1991 to 1994. Individuals were classified by the aggregate SEP of their area of residency. These were analysed as potential modifiers of the temperature-mortality relationship. Among the elderly we observed a 2.6% increase in all-cause mortality per degree increase in temperature above 20 degrees C, and a 5.5% increase per degree drop in temperature below 20 degrees C, after adjustment for confounding. Relationships were similar in children, but somewhat weaker in adults. Cold effects were present for deaths due to cardiovascular disease (CVD), respiratory, and other causes, with effects being greatest in the respiratory group. Heat effects were not found for CVD deaths in adults, but otherwise varied little by cause of mortality. There was little evidence for a modification of the mortality effects of cold or heat by SEP. These findings show that the U-shaped pattern of the temperature-mortality relationship found in cooler northern countries occurs also in a sub-tropical city. In addition, the relative effects of temperature were similar in each socioeconomic grouping.
Article
Some studies suggest low temperatures can affect mortality, especially deaths associated with circulatory and respiratory conditions. We investigated the association between ischemic stroke onset and decrease in temperature in 545 patients over a 3-year period (January 1998 to December 2000) in Incheon, Korea. We used a case-crossover study design to assess changes in the risk of ischemic stroke during a brief hazard period after exposure to decrease in temperature. For each subject, the case period was matched to 2 control periods exactly 1 week before and after onset of the ischemic stroke. Decreased ambient temperature was associated with risk of acute ischemic stroke. The strongest effect was seen on day after exposure to cold weather. The odds ratio (OR) for an interquartile range decrease in temperature was 2.9 (95% confidence interval [CI] = 1.5-5.3). The risk period was 24-48 hours after cold exposure. Risk estimates associated with decreased temperature were greater in the winter than in the summer. Women, persons greater than 65 years of age, nonobese persons, and those with previous hypertension or hypercholesterolemia were more susceptible to cold-induced ischemic stroke. These results suggest that stroke occurrence rises with decreasing temperature, and that even a moderate decrease in temperature can increase the risk of ischemic stroke. Susceptible people should take steps to protect themselves from cold, especially in the winter.
Article
Full-text available
Objective: To investigate whether outdoor air pollution levels in London influence daily mortality. Design: Poisson regression analysis of daily counts of deaths, with adjustment for effects of secular trend, seasonal and other cyclical factors, day of the week, holidays, influenza epidemic, temperature, humidity, and autocorrelation, from April 1987 to March 1992. Pollution variables were particles (black smoke), sulphur dioxide, ozone, and nitrogen dioxide, lagged 0-3 days. Setting: Greater London. Outcome measures: Relative risk of death from all causes (excluding accidents), respiratory disease, and cardiovascular disease. Results: Ozone levels (same day) were associated with a significant increase in all cause, cardiovascular, and respiratory mortality; the effects were greater in the warm season (April to September) and were independent of the effects of other pollutants. In the warm season an increase of the eight hour ozone concentration from the 10th to the 90th centile of the seasonal range (7-36 ppb) was associated with an increase of 3.5% (95% confidence interval 1.7 to 5.3), 3.6% (1.04 to 6.1), and 5.4% (0.4 to 10.7) in all cause, cardiovascular, and respiratory mortality respectively. Black smoke concentrations on the previous day were significantly associated with all cause mortality, and this effect was also greater in the warm season and was independent of the effects of other pollutants. For black smoke an increase from the 10th to 90th centile in the warm season (7-19 µg/m3) was associated with an increase of 2.5% (0.9 to 4.1) in all cause mortality. Significant but smaller and less consistent effects were also observed for nitrogen dioxide and sulphur dioxide. Conclusion: Daily variations in air pollution within the range currently occurring in London may have an adverse effect on daily mortality. Key messages Evidence from other countries suggests that similar levels of pollution may be associated with short term health effectsThis study suggests that air pollution due to particles and ozone may be associated with increased daily mortality in LondonThe evidence is less convincing for nitrogen dioxide and sulphur dioxideIt would be prudent to assume that these associations are causal and to reduce air pollution levels with the help of appropriate abate- ment policies
Article
Full-text available
Objective: To test the efficacy of a graded aerobic exercise programme in the chronic fatigue syndrome. Design: Randomised controlled trial with control treatment crossover after the first follow up examination. Setting: Chronic fatigue clinic in a general hospital department of psychiatry.
Article
Full-text available
To evaluate how mortality and protective measures against exposure to cold change as temperatures fall between October and March in a region of Russia with a mean winter temperature below -6 degrees C. Interview to assess factors associated with cold stress both indoors and outdoors, to measure temperatures in living room, and to survey unheated rooms. Sverdlovsk Oblast (district), Yekaterinburg, Russia. Residents aged 50-59 and 65-74 living within approximately 140 km of Yekaterinburg in Sverdlovsk Oblast. Survey of sample of 1000 residents equally distributed by sex and age groups. Regression analysis was used to relate data on indoor heating and temperatures, the amount of clothing worn, the amount of physical activity, and shivering while outside, to outdoor temperature; results were compared with mortality patterns for ischaemic heart disease, cerebrovascular disease, respiratory disease, and mortality from all causes. As mean daily temperatures fell to 0 degree C the amount of clothing worn outdoors increased, physical activity while outdoors became more continuous, and only 11 (6.6%) of the 167 people surveyed who went outdoors at temperatures above 0 degree C reported shivering. The mean temperature in living rooms in the evening remained above 21.9 degrees C. Mortality from ischaemic heart disease, cerebrovascular disease, respiratory disease, and all causes did not change. As the temperature fell below 0 degree C the number of items of clothing worn plateaued at 16.0 and the number of layers at 3.7. With regression analysis, shivering outdoors was found to increase progressively to 34.6% (P < 0.001) of excursions at -25 degrees C, and mortality (after declining slightly) rose progressively (all cause mortality rose by 1.15% for each 1 degree C drop in temperature from 0 degree C to -29.6 degrees C, 95% confidence interval 0.97% to 1.32%). 94.2% of bedrooms were directly heated, and evening temperatures in the living room averaged 19.8 degrees C even when outside temperatures reached -25 degrees C. Outdoor cold stress and mortality in Yekaterinburg increased only when the mean daily temperature dropped below 0 degree C. At temperatures down to 0 degree C cold stress and excess mortality were prevented by increasing the number of items of clothing worn and the amount of physical activity outdoors in combination with maintaining warmth in houses.
Article
Full-text available
In Erfurt, Germany, unfavorable geography and emissions from coal burning lead to very high ambient pollution (up to about 4000 micrograms/m3 SO2 in 1980-89). To assess possible health effects of these exposures, total daily mortality was obtained for this same period. A multivariate model was fitted, including corrections for long-term fluctuations, influenza epidemics, and meterology, before analyzing the effect of pollution. The best fit for pollution was obtained for log (SO2 daily mean) with a lag of 2 days. Daily mortality increased by 10% for an increase in SO2 from 23 to 929 micrograms/m3 (5% quantile to 95% quantile). A harvesting effect (fewer people die on a given day if more deaths occurred in the last 15 days) may modify this by +/- 2%. The effect for particulates (SP, 1988-89 only) was stronger than the effect of SO2. Log SP (daily mean) increasing from 15 micrograms/m3 to 331 micrograms/m3 (5% quantile to 95% quantile) was associated with a 22% increase in mortality. Depending on harvesting, the observable effect may lie between 14% and 27%. There is no indication of a threshold or synergism. The effects of air pollution are smaller than the effects of influenza epidemics and are of the same size as meterologic effects. The results for the lower end of the dose range are in agreement with linear models fitted in studies of moderate air pollution and episode studies. Images Figure 1. Figure 2.
Article
Full-text available
To explore whether the apparent low threshold for the mortality effects of air pollution could be the result of confounding. The associations between mortality and sulphur dioxide (SO2) were analysed taking into account potential confounding factors. The Netherlands, 1979-87. The number of deaths listed by the day on which the death occurred and by the cause of death were obtained from the Netherlands Central Bureau of Statistics. Mortality from all causes and mortality from four large groups of causes (neoplasms, cardiovascular diseases, respiratory diseases, and external causes) were related to the daily levels of SO2 air pollution and potential confounders (available from various sources) using log-linear regression analysis. Variables considered as potential confounders were: average temperature; difference between maximum and minimum temperatures; amount of precipitation; air humidity; wind speed; influenza incidence; and calendar year, month, and weekday. Both lagged and unlagged effects of the meteorological and influenza variables were considered. Average temperature was represented by two variables--'cold', temperatures below 16.5 degrees C, and 'warm', those above 16.5 degrees C--to allow for the V shaped relation between temperature and mortality. The positive regression coefficient for the univariate effect of SO2 density on mortality from all causes dwindles to close to zero when all potential confounding variables are taken into account. The most important of these represents the lagged (one to five days) effect of low temperatures. Low temperatures have strong lagged effects on mortality, and often precede relatively high SO2 densities in the Netherlands. Results were similar for separate causes of death. While univariate associations suggest an effect of air pollution on mortality in all four cause of death groups, multivariate analyses show these effects, including that on mortality from respiratory diseases, are a result of confounding. The SO2 density (or that of compounds closely associated with SO2) does not seem to have any short term effect on mortality in the Netherlands. SO2 levels higher than those currently reached in the Netherlands (above 200 micrograms/m3) may have a measurable effect on mortality and this should be investigated. Furthermore, analyses of the public health impact of outdoor air pollution should properly control for the lagged effects of temperature.
Article
Full-text available
To review the issues and methodologies in epidemiologic time series studies of daily counts of mortality and hospital admissions and illustrate some of the methodologies. This is a review paper with an example drawn from hospital admissions of the elderly in Cleveland, Ohio, USA. The central issue is control for seasonality. Both over and under control are possible, and the use of diagnostics, including plots, is necessary. Weather dependence is probably non-linear, and adequate methods are necessary to adjust for this. In Cleveland, the use of categorical variables for weather and sinusoidal terms for filtering season are illustrated. After control for season, weather, and day of the week effects, hospital admission of persons aged 65 and older in Cleveland for respiratory illness was associated with ozone (RR = 1.09, 95% CI 1.02, 1.16) and particulates (PM10 (RR = 1.12, 95% CI 1.01, 1.24), and marginally associated with sulphur dioxide (SO2) (RR = 1.03, 95% CI = 0.99, 1.06). All of the relative risks are for a 100 micrograms/m3 increase in the pollutant. Several adequate methods exist to control for weather and seasonality while examining the associations between air pollution and daily counts of mortality and morbidity. In each case, care and judgement are required.
Article
Full-text available
The relationship between air pollution and mortality in East Berlin was examined for the winters of 1981-1989. Regression analysis included daily mean levels of sulphur dioxide (SO2) and suspended particulates (SP), and was controlled for temperature, humidity, week-day, month, and year. Moving averages of previous pollution were also used. Each pollutant was a significant contributor to excess mortality. The strongest association was found for mortality lagged for 2 days, which depended significantly on the level of SP (beta for in SP = 0.876; P = 0.008) and SO2 (beta for in SO2 = 0.635; P = 0.012), when regressed separately. When omitting days with pollutant concentrations above 150 micrograms m-3, the pollutant-mortality relationship was linear, and a 100 micrograms m-3 increase was associated with a 6.1% (SP) and 4.5% (SO2) mortality increase 2 days later, when pollutants were considered separately; this was reduced to 4.6% (SP) and 2.8% (SO2) increase, when both were considered simultaneously. The results show that short-term associations between air pollutants and mortality in East Berlin did exist during the winters 1981-1989. Since the coefficients for SP and SO2 dropped when controlling for the other pollutant species, a similar strength of association with mortality for both pollutants was found.
Article
Full-text available
In a previous paper, we showed that the mean effects on daily mortality associated with air pollution are essentially the same for gases and particulate matter (PM) and are invariant with respect to particle size and composition, based on 27 statistical studies that had been published at that time. Since then, a new analysis reported stronger mortality associations for the fine fractions of PM obtained from dichotomous samplers, relative to the coarse fractions. In this paper, we show that differential measurement errors known to be present in dichotomous sampler data preclude reliable determination of such statistical relationships by particle size. Further, it is necessary to consider gaseous pollutants simultaneously with particles to provide robust estimates of the responsibilities for the implied daily mortality gradients. Finally, certain regression model specifications may be sensitive to differences in frequency distribution characteristics according to particle size.
Article
Full-text available
To identify the time courses and magnitude of ischaemic heart (IHD), respiratory (RES), and all cause mortality associated with common 20-30 day patterns of cold weather in order to assess links between cold exposure and mortality. Daily temperatures and daily mortality on successive days before and after a reference day were regressed on the temperature of the reference day using high pass filtered data in which changes with a cycle length < 80 days were unaffected (< 2%), but slower cyclical changes and trends were partly or completely suppressed. This provided the short term patterns of both temperature and mortality associated with a one day displacement of temperature. The results were compared with simple regressions of unfiltered mortality on temperature at successive delays. STUDY POPULATION AND SETTING: Population of south east England, including London, over 50 years of age from 1976-92. Colder than average days in the linear range 15 to 0 degrees C were associated with a "run up" of cold weather for 10-15 days beforehand and a "run down" for 10-15 days afterwards. The increases in deaths were maximal at 3 days after the peak in cold for IHD, at 12 days for RES, and at 3 days for all cause mortality. The increase lasted approximately 40 days after the peak in cold. RES deaths were significantly delayed compared with IHD deaths. Excess deaths per million associated with these short term temperature displacements were 7.3 for IHD, 5.8 for RES, and 24.7 for all cause, per one day fall of 1 degree C. These were greater by 52% for IHD, 17% for RES, and 37% for all cause mortality than the overall increases in daily mortality per degree C fall, at optimal delays, indicated by regressions using unfiltered data. Similar analyses of data at 0 to -6.7 degrees C showed an immediate rise in IHD mortality after cold, followed by a fall in both IHD and RES mortality rates which peaked 17 and 20 days respectively after a peak in cold. Twenty to 30 day patterns of cold weather below 15 degrees C were followed:(1) rapidly by IHD deaths, consistent with known thrombogenic and reflex consequences of personal cold exposure; and (2) by delayed increases in RES and associated IHD deaths in the range 0 to 15 degrees C, which were reversed for a few degrees below 0 degree C, and were probably multifactorial in cause. These patterns provide evidence that personal exposure to cold has a large role in the excess mortality of winter.
Article
Full-text available
To assess how effectively measures adopted in extreme cold in Yakutsk control winter mortality. Interviews to assess outdoor clothing and measure indoor temperatures; regressions of these and of delayed cause-specific mortalities on temperature. Setting Yakutsk, east Siberia, Russia. All people aged 50-59 and 65-74 years living within 400 km of Yakutsk during 1989-95 and sample of 1002 men and women who agreed to be interviewed. Daily mortality from all causes and from ischaemic heart, cerebrovascular, and respiratory disease. Mean temperature for October-March 1989-95 was -26.6 degreesC. At 10.2 degrees C people wore 3.30 (95% confidence interval 3.08 to 3.53) layers of clothing outdoors, increasing to 4.39 (4.13 to 4.66; P<0. 0001) layers at -20 degrees C. Thick coats, often of fur, replaced anoraks as temperature fell to -48.2 degrees C. 82% of people went out each day when temperatures were 10.2 degrees C to -20 degrees C, but below -20 degrees C the proportion fell steadily to 44% (35% to 53%) at -48.2 degrees C (P<0.001), and overall shivering outdoors did not increase. Living room temperature was 17.9 (17.2 to 18.5) degrees C at 10.2 degrees C outdoors, 19.6 (18.8 to 20.4) degrees C at -20 degrees C, and 19.1 (18.6 to 19.6) degrees C at -48.2 degrees C. Mortality from all causes and from ischaemic heart and respiratory disease was unaffected by the fall in temperature. Mortality from respiratory disease (daily deaths per million) rose from 4.7 (4.3 to 5.1) to 5.1 (4.4 to 5.7) (P=0.03), but this was offset by a fall in deaths from injury. People in Yakutsk wore very warm clothing, and in extremely cold weather stayed indoors in warm housing, preventing the increases in mortality seen in winter in milder regions of the world. Only respiratory mortality rose, perhaps because of breathing cold air.
Article
Full-text available
A previous study of the short term effects of air pollution in London from April 1987 to March 1992 found associations between all cause mortality and black smoke and ozone, but no clear evidence of specificity for cardiorespiratory deaths. London data from 1992 to 1994 were analysed to examine the consistency of results over time and to include particles with a mean aerodynamic diameter of 10 microns (PM10) and carbon monoxide. Poisson regression was used of daily mortality counts grouped by age and diagnosis, adjusting for trend, seasonality, calendar effects, deaths from influenza, meteorology, and serial correlation. The pollutants examined were particles (PM10 and black smoke), nitrogen dioxide, ozone, sulphur dioxide, and carbon monoxide with single and cumulative lags up to 3 days. No significant associations were found between any pollutant and all cause mortality, but, with the exception of ozone, all estimates were positive. Each pollutant apart from ozone was significantly associated with respiratory mortality; PM10 showed the largest effect (4% increase in deaths of all ages for a 10th-90th percentile increment). The pollutants significantly associated with cardiovascular deaths were nitrogen dioxide, ozone, and black smoke but there was no evidence of an association with PM10. In two pollutant models of respiratory deaths, the effect of black smoke, which in London indicates fine particles of diesel origin, was independent of that of PM10, but not vice versa. These results from a new data set confirm a previous report that there are associations between various air pollutants and daily mortality in London. This new study found greater specificity for associations with respiratory and cardiovascular deaths, and this increases the plausibility of a causal explanation. However, the effects of ozone found in the earlier study were not replicated. The fraction of PM10 which comprises black smoke accounted for much of the effect of PM10.
Article
Rahtenbeck S I (Gondar College of Medical Sciences, PO Box 196, Gondar, Ethiopia), Kahl H. Air pollution and mortality in East Berlin during the winters of 1981–1989. International Journal of Epidemiology 1996; 25: 1220–1226. Background The relationship between air pollution and mortality in East Berlin was examined for the winters of 1981–1989. Methods Regression analysis included daily mean levels of sulphur dioxide (SO2) and suspended particulates (SP), and was controlled for temperature, humidity, week-day, month, and year. Moving averages of previous pollution were also used. Results Each pollutant was a significant contributor to excess mortality. The strongest association was found for mortality lagged for 2 days, which depended significantly on the level of SP (β for In SP = 0.876; P = 0 008) and SO2 (β for In SO2 = 0.635; P = 0.012), when regressed separately. When omitting days with pollutant concentrations above 150 μg m⁻³, the pollutant-mortality relationship was linear, and a 100 μg m⁻³ increase was associated with a 6.1% (SP) and 4.5% (SO2) mortality increase 2 days later, when pollutants were considered separately; this was reduced to 4.6% (SP) and 2.8% (SO2) increase, when both were considered simultaneously. Conclusions The results show that short-term associations between air pollutants and mortality in East Berlin did exist during the winters 1981–1989. Since the coefficients for SP and SO2 dropped when controlling for the other pollutant species, a similar strength of association with mortality for both pollutant was found.
Article
BACKGROUND: Differences in baseline mortality, age structure, and influenza epidemics confound comparisons of cold-related increases in mortality between regions with different climates. The Eurowinter study aimed to assess whether increases in mortality per 1 degree C fall in temperature differ in various European regions and to relate any differences to usual winter climate and measures to protect against cold. METHODS: Percentage increases in deaths per day per 1 degree C fall in temperature below 18 degrees C (indices of cold-related mortality) were estimated by generalised linear modelling. We assessed protective factors by surveys and adjusted by regression to 7 degrees C outdoor temperature. Cause-specific data gathered from 1988 to 1992 were analysed by multiple regression for men and women aged 50-59 and 65-74 in north Finland, south Finland, Baden-Wurttemburg, the Netherlands, London, and north Italy (24 groups). We used a similar method to analyse 1992 data in Athens and Palermo. FINDINGS: The percentage increases in all-cause mortality per 1 degree C fall in temperature below 18 degrees C were greater in warmer regions than in colder regions (eg, Athens 2.15% [95% CI 1.20-3.10] vs south Finland 0.27% [0.15-0.40]). At an outdoor temperature of 7 degrees C, the mean living-room temperature was 19.2 degrees C in Athens and 21.7 degrees C in south Finland; 13% and 72% of people in these regions, respectively, wore hats when outdoors at 7 degrees C. Multiple regression analyses (with allowance for sex and age, in the six regions with full data) showed that high indices of cold-related mortality were associated with high mean winter temperatures, low living-room temperatures, limited bedroom heating, low proportions of people wearing hats, gloves, and anoraks, and inactivity and shivering when outdoors at 7 degrees C (p < 0.01 for all-cause mortality and respiratory mortality; p > 0.05 for mortality from ischaemic heart disease and cerebrovascular disease). INTERPRETATION: Mortality increased to a greater extent with given fall of temperature in regions with warm winters, in populations with cooler homes, and among people who wore fewer clothes and were less active outdoors.
Article
The visual information on a scatterplot can be greatly enhanced, with little additional cost, by computing and plotting smoothed points. Robust locally weighted regression is a method for smoothing a scatterplot, (x i , y i ), i = 1, …, n, in which the fitted value at z k is the value of a polynomial fit to the data using weighted least squares, where the weight for (x i , y i ) is large if x i is close to x k and small if it is not. A robust fitting procedure is used that guards against deviant points distorting the smoothed points. Visual, computational, and statistical issues of robust locally weighted regression are discussed. Several examples, including data on lead intoxication, are used to illustrate the methodology.
Article
Particulate air pollution has been associated with increased mortality during episodes of high pollution concentrations. The relationship at lower concentrations has been more controversial, as has the relative role of particles and sulfur dioxide. Replication has been difficult because suspended particle concentrations are usually measured only every sixth day in the U.S. This study used concurrent measurements of total suspended particulates (TSP) and airport visibility from every sixth day sampling for 10 years to fit a predictive model for TSP. Predicted daily TSP concentrations were then correlated with daily mortality counts in Poisson regression models controlling for season, weather, time trends, overdispersion, and serial correlation. A significant correlation (P less than 0.0001) was found between predicted TSP and daily mortality. This correlation was independent of sulfur dioxide, but not vice versa. The magnitude of the effect was very similar to results recently reported from Steubenville, Ohio (using actual TSP measurements), with each 100 micrograms/m3 increase in TSP resulting in a 6% increase in mortality. Graphical analysis indicated a dose-response relationship with no evidence of a threshold down to concentrations below half of the National Ambient Air Quality Standards for particulate matter.
Article
Derriennic F (Inserm U170, 16 Av PV Couturier, F-94807 Villejuif, Cedex, France), Richardson S, Mollie A and Lellouch J. Short-term effects of sulphur dioxide pollution on mortality in two French cities. International Journal of Epidemiology 1989, 18: 186–197. To assess the short-term effects of sulphur dioxide (SO2) atmospheric pollution on mortality a study was conducted in two large French cities, using daily measures of pollution and mortality. A statistically significant association between daily SO2 pollution and respiratory deaths up to 10 days later was shown in both cities for both male and female populations together in the age group 65 years and over. No coherent results were found between SO2 pollution and cardiovascular deaths, or between suspended particulates and either respiratory or cardiovascular deaths. Particular emphasis was put on the use of correct statistical procedures using time series analysis and on the comparison of the part played by SO2 or suspended particulates on mortality.
Article
Short-term effects of air pollution on mortality in Athens during the years 1975-1982 were studied. Daily values of sulphur dioxide (SO2) and smoke, measured by a five-station network of the National Observatory of Athens, were used as air pollution indicators. Mortality data were abstracted from the Town Registries of Athens and 18 other contiguous towns within the Greater Athens area. It was found that the adjusted daily mortality (estimated by subtracting from the observed value of mortality an 'expected' value, calculated after fitting a sinusoid curve to the empirical mortality data) depends positively and significantly on the level of SO2 (b = +0.0058, p = 0.05). This relation is independent of temperature, relative humidity, secular, seasonal, monthly and weekly variations of mortality as well as of synergistic effects of the above variables with season. No relation was found between smoke and adjusted daily mortality. An analysis for the determination of a possible threshold in the levels of SO2 causing health effects was also undertaken, by studying changes in the SO2 regression coefficients after successive deletion from the regression model of the days with the highest SO2 values. Our study shows that if there is an SO2 threshold it must lie slightly below the level of 150 micrograms/m3 (mean daily value).
Article
Six hours of mild surface cooling in moving air at 24 degrees C with little fall in core temperature (0.4 degree C) increased the packed cell volume by 7% and increased the platelet count and usually the mean platelet volume to produce a 15% increase in the fraction of plasma volume occupied by platelets. Little of these increases occurred in the first hour. Whole blood viscosity increased by 21%; plasma viscosity usually increased, and arterial pressure rose on average from 126/69 to 138/87 mm Hg. Plasma cholesterol concentration increased, in both high and low density lipoprotein fractions, but values of total lipoprotein and lipoprotein fractions were unchanged. The increases in platelets, red cells, and viscosity associated with normal thermoregulatory adjustments to mild surface cooling provide a probable explanation for rapid increases in coronary and cerebral thrombosis in cold weather. The raised arterial pressure and possibly cholesterol concentration may contribute to slower components of the increased thrombosis.
Article
There are approximately 20,000 excess deaths from cardiovascular disease each winter in England and Wales. The reasons for the excess have not been fully elucidated. For one year, we studied 96 men and women aged 65-74 living in their own homes in order to examine seasonal variation in plasma fibrinogen and factor VII clotting activity (FVIIc), and to investigate relationships with infection and other cardiovascular-disease risk factors. Both fibrinogen and FVIIc plasma values were greater in winter with estimated winter-summer differences (confidence intervals) of 0.13 (0.05-0.20) g/L for fibrinogen and 4.2 (1.2-7.1)% of standard for FVIIc. These differences could account for 15% and 9% increases in ischaemic heart disease risk in winter respectively. After adjustment for confounding by season, fibrinogen was strongly related to neutrophil count (p < 0.0001), C-reactive protein (p < 0.0001), alpha 1-antichymotrypsin (p < 0.0001), and self-reported cough (p < 0.0001) and coryza (p = 0.0004), but not to ambient temperature. Therefore, we suggest that seasonal variation in fibrinogen might be induced by winter respiratory infections via activation of the acute phase response. Seasonal variations in the cardiovascular risk factors fibrinogen and FVIIc provide further possible explanations for the marked seasonal variation in death from ischaemic heart disease and stroke in the elderly.
Article
1. Six elderly (66-71 years) and six young (20-23 years) subjects (half of each group women) were cooled for 2 h in moving air at 18°C to investigate possible causes of increased mortality from arterial thrombosis among elderly people in cold weather. Compared with thermoneutral control experiments, skin temperature (trunk) fell from 35.5 to 29.5°C, with little change in core temperature. 2. Erythrocyte count rose in the cold from 4.29 to 4.69 × 1012/l, without a change in mean corpuscular volume, indicating a 14% or 438 ml decline in plasma volume; increased excretion of water, Na+ and K+ accounted for loss of only 179 ml of extracellular water. 3. Plasma cholesterol and fibrinogen concentrations rose in the elderly subjects from 4.9 mmol/l and 2.97 g/l (control) to 5.45 mmol/l and 3.39 g/l in the cold, and in the young subjects from 3.33 mmol/l and 1.84 g/l (control) to 3.77 mmol/l and 2.07 g/l in the cold. Increases were significant for the elderly subjects, the young subjects and the group as a whole, except for cholesterol in the young subjects, and all were close to those expected from the fall in plasma volume. 4. Plasma levels of Protein C and factor X did not increase significantly in the cold in the elderly subjects, young subjects, or the group as a whole. 5. The results suggest that loss of plasma fluid in the cold concentrates major risk factors for arterial thrombosis, while small molecules, including protective Protein C, redistribute to interstitial fluid.
Article
Results from 31 epidemiology studies linking air pollution with premature mortality are compared and synthesized. Consistent positive associations between mortality and various measures of air pollution have been shown within each of two fundamentally different types of regression studies and in many variations within these basic types; this is extremely unlikely to have occurred by chance. In this paper, the measure of risk used is the elasticity, which is a dimensionless regression coefficient defined as the percentage change in the dependent variable associated with a 1% change in an independent variable, evaluated at the means. This metric has the advantage of independence from measurement units and averaging times, and is thus suitable for comparisons within and between studies involving different pollutants. Two basic types of studies are considered: time-series studies involving daily perturbations, and cross-sectional studies involving longer-term spatial gradients. The latter include prospective studies of differences in individual survival rates in different locations and studies of the differences in annual mortality rates for various communities. For a given data set, time-series regression results will vary according to the seasonal adjustment method used, the covariates included, and the lag structure assumed. The results from both types of cross-sectional regressions are highly dependent on the methods used to control for socioeconomic and personal lifestyle factors and on data quality. A major issue for all of these studies is that of partitioning the response among collinear pollution and weather variables. Previous studies showed that the variable with the least exposure measurement error may be favored in multiple regressions; assigning precise numerical results to a single pollutant is not possible under these circumstances. We found that the mean overall elasticity as obtained from time-series studies for mortality with respect to various air pollutants entered jointly was about 0.048, with a range from 0.01 to 0.12. This implies that about 5% of daily mortality is associated with air pollution, on average. The corresponding values from population-based cross-sectional studies were similar in magnitude, but the results from the three recent prospective studies varied from zero to about five times as much. Long-term responses in excess of short-term responses might be interpreted as showing the existence of chronic effects, but the uncertainties inherent in both types of studies make such an interpretation problematic.
Article
Several recent studies have reported associations between short-term changes in air pollution and respiratory hospital admissions. Most of those studies analyzed locations where there was a high correlation between airborne particles and sulfur dioxide (SO2), and between all air pollutants and temperature. Here, I seek to replicate the previous findings in a location where SO2 concentrations were trivial, and the correlation between both airborne particles and ozone with temperature was considerably lower than in previous studies. I constructed daily counts of admissions to all hospitals in Spokane, WA, for respiratory disease (International Classification of Diseases, 9th revision, codes 460-519) for persons age 65 years and older. I computed average daily concentrations of airborne particles whose diameter is 10 microns or less (PM10) and ozone (O3) from all monitors in each city, and I obtained daily average temperature and humidity from the U.S. weather service. SO2 concentrations in Spokane were so low that monitoring was discontinued. I regressed daily respiratory admission counts on temperature, humidity, day of the week indicators, and air pollution. I used a Poisson regression analysis and removed long wavelength patterns using a nonparametric smooth function of day of study. I dealt with a possible U-shaped dependence of admissions on temperature and/or humidity by using nonparametric smooth functions of weather variables as well. I then examined sensitivity analyses to control for weather. Both PM10 and ozone were associated with increased risk of respiratory hospital admissions [relative risk (RR) = 1.085; 95% confidence interval (CI) = 1.036-1.136 for a 50-microgram per m3 increase in PM10, and RR = 1.244; 95% CI = 1.002-1.544 for a 50-microgram per m3 increase in peak-hour ozone]. The PM10 association was insensitive to alternative methods of control for weather, including exclusion of extreme temperature days and control for temperature on multiple days. The ozone results were more sensitive to the approach for weather control. The magnitude of the PM10 effect in this location, where SO2 was essentially not present, and where the correlation between PM10 and temperature was close to zero, was similar to that reported in other locations in the eastern United States and Europe, where confounding by weather and SO2 is a more substantial concern.
Article
Study objective and design: For the APHEA study, the short term effects of air pollutants on human health were investigated in a comparable way in various European cities. Daily mortality was used as one of the health effects indicators. This report aims to demonstrate the steps in epidemiological model building in this type of time series analysis aimed at detecting short term effects under a poisson distribution assumption and shows the tools for decision making. In addition, it assesses the impact of these steps on the pollution effect estimates. Setting: Köln, Germany, is a city of one million inhabitants. It is densely populated with a warm, humid, unfavourable climate and a high traffic density. In previous studies, smog episodes were found to increase mortality and higher sulphur dioxide (SO2) levels were connected with increases in the number of episodes of croup. Participants, materials and methods: Daily total mortality was obtained for 1975-85. SO2, total suspended particulates, and nitrogen dioxide (NO2) data were available from two to five stations for the city area, and size fractionated PM7 data from a neighbouring city. The main tools were time series plots of the raw data, predicted and residual data, the partial autocorrelation function and periodogram of the residuals, cross correlations of prefiltered series, plots of categorised influences, chi 2 statistics of influences and sensitivity analyses taking overdispersion and autocorrelation into account. Results and conclusions: With regard to model building, it is concluded that seasonal and epidemic correction are the most important steps. The actual model chosen depends very much on the properties of the data set. For the pollution effect estimates, trend, season, and epidemic corrections are important to avoid overestimation of the effect, while an appropriate short term meterology influence correction model may actually prevent underestimation. When the model leaves very little over-dispersion and autocorrelation in the residuals, which indicates a good fit, correction for them has consequently little impact. Given the model, most of the range of SO2 values (5th centile to 95th centile) led to a 3-4% increase in mortality (significant), particulates led to a 2% increase (borderline significant, less data than for SO2), and NO2 had no relationship with mortality (measurements possibly not representative of actual exposure). Effects were usually delayed by a day.
Article
There is evidence that air pollution in Athens between 1975 and 1987 had adverse short term health effects. The short term effects of "winter type" air pollution on the daily total number of deaths are investigated for the period 1987-91 as part of the European Community multi centre APHEA project. A temporal study using aggregated data is presented. The associations of the daily time series of three pollutants, sulphur dioxide (SO2), black smoke (BS), and carbon monoxide (CO) and the daily total number of deaths in the Athens area were assessed. The average measurement from three stations was used for each pollutant. The daily number of deaths was recorded from the Athens Town Registry and the registries of the 18 municipalities contiguous to Athens. Data on the mean daily temperature (degree C) and relative humidity (%) were also used. Poisson autoregressive models that also allowed for overdispersion were used. Seasonality, other long term patterns, temperature, humidity, day of the week, and holidays were adjusted for. Several a priori defined pollutant transformations and lags were investigated. One day measurements as well as cumulative exposure effects were assessed. Effect modification by season as well as among pollutants was tested. Linear terms were used for all pollutants. The magnitude of the effect was greater at lags 0 for CO and 1 for BS and SO2 gradually declining after lag 1. For an increase of 100 micrograms/m3 in SO2 and BS there were corresponding increases (95% CI) of 12% (7%, 16%) and 5% (3%, 8%) in the daily total numbers of deaths, while for an increase of 10 micrograms/m3 in CO the increase (95% CI) in the daily total number of deaths was 10% (5%, 15%). A significant interaction of the effects of SO2 with season were found. The strongest effect was observed during the winter, when higher levels of SO2 were observed. A stronger effect of SO2 on the daily total number of deaths was observed when the levels of BS were > 100 micrograms/m3. These results strengthen the evidence of a causal association between ambient particle, SO2, or CO levels in the air and the daily total number of deaths and points to an important public health issue for the Athens population.
Article
We review epidemiologic studies of particulate air pollution and mortality in U.S. cities with respect to important methodologic issues. Many of these studies suffer from serious deficiencies in their control of the confounding effects of other pollutants. As a consequence, the small risks reported to be associated with the particulate component of air pollution could easily be attributed to residual confounding by co-pollutants. Most studies, moreover, have not considered modification of air pollution effects by seasonal factors, making the interpretation of the estimated risks difficult. We use a new analysis of mortality in Philadelphia that considers four pollutants simultaneously as well as seasonal effects to illustrate the methodologic issues raised in this paper. Air pollution, which is a complex mixture, appears to be associated with mortality even at the generally low levels of pollution in U.S. cities, but currently neither the statistical tools nor the biological understanding of mechanisms exists to tease out the contribution made by each component of this mixture. We conclude that it is not possible with the present evidence to show a convincing correlation between particulate air pollution and mortality.
Article
Analyses involving data from many locations throughout the world have now been conducted to assess the association between air pollution and mortality. To date, six independent analyses of mortality data for Philadelphia, Pennsylvania, have been reported. In this new analysis of Philadelphia data for 1974–1988, Poisson regression models were developed to estimate the increased risk of daily mortality associated with air pollution while controlling for longer-term time trends and season and for weather. Model development was based on prior understanding of the effects of these factors on mortality and on consideration of model fit. The authors found moderate correlations of daily concentrations of total suspended particles (TSP), sulfur dioxide (SO2), nitrogen dioxide (NO2), and carbon monoxide (CO), and only slight correlations of ozone (O3) with other pollutants. When included individually in the model, the means of current and previous days' levels of TSP, SO2 and O3 had statistically significant effects on total mortality; pollutant increases of an interquartile range (34.5 μg/m3 12.9 ppb, and 20.2 ppb, respectively) were associated with increases in mortality of around 1% for TSP and SO2 and of around 2% for O3. The effects of TSP and SO2 were diminished when both pollutants were simultaneously included in the model, whether pairwise or in the full multi-pollutant model. These analyses confirm the association between TSP and mortality found in previous studies in Philadelphia and show that the association is robust to consideration of other pollutants in the model.
Article
Editor—The APHEA project (air pollution and health: a European approach) found that the effects of daily variation in air pollution on mortality were significantly stronger in western Europe than in eastern Europe.1 The authors have put forward several explanations for this inconsistency, all of which, generally speaking, suggest that the small effects found in eastern Europe are an artefact. We propose a less dismissive explanation. Inspired by the Eurowinter study,2 we plotted the relative risk of death in cities in the APHEA project1 against …
Article
Because weather has the potential to confound or modify the pollution-mortality relationship, researchers have developed several approaches for controlling it in estimating the independent effect of air pollution on mortality. This report considers the consequences of using alternative approaches to controlling for weather and explores modification of air pollution effects by weather, as weather patterns could plausibly alter air pollution's effect on health. We analyzed 1973-1980 total mortality data for Philadelphia using four weather models and compared estimates of the effects of TSP and SO2 on mortality using a Poisson regression model. Two synoptic categories developed by Kalkstein were selected--the Temporal Synoptic Index (TSI) and the Spatial Synoptic Classification (SSC)--and compared with (1) descriptive models developed by Schwartz and Dockery (S-D); and (2) LOESS, a non-parametric function of the previous day's temperature and dew point. We considered model fit using Akaike's Information Criterion (AIC) and changes in the estimated effects of TSP and SO2. In the full-year analysis, S-D is better than LOESS at predicting mortality, and S-D and LOESS are better than TSI, as measured by AIC. When TSP or SO2 was fit alone, the results were qualitatively similar, regardless of how weather was controlled; when TSP and SO2 were fit simultaneously, the S-D and LOESS models give qualitatively different results than TSI, which attributes more of the pollution effect to SO2 than to TSP. Model fit is substantially poorer with TSI. This pattern was repeated in analyses of summer and winter months, which included SSC. In summary, using synoptic weather categories in regression models does not meaningfully change the association between mortality and air pollution indexes. We also found little evidence that weather conditions modified the effect of pollution, regardless of the approach used to represent weather.
Article
Alveolar macrophages (AM), obtained by lavage from the rat lung, were allowed to ingest aggregated ultrafine carbon particles, about 1 microgram/10(6) AM, which is a realistic result of long-term exposure to ambient air. The effects of the ingested carbon on the phagocytosis of test particles and oxidative metabolism of the AM were studied. In addition, the effects of short-term (40 min or 2 h) and long-term (28 or 44 h) incubation with interferon gamma (IFN-gamma) on AM loaded and unloaded with carbon were investigated. Phagocytic activity was studied using fluorescein-labeled 3.2-microgram silica particles. The attachment and ingestion processes were evaluated separately. The ingested carbon markedly impaired the phagocytosis of silica particles; the accumulated attachment (sum of attached and ingested particles per AM) decreased from 5.0 to 4.2 particles/AM and the ingested fraction (number of ingested particles per AM divided with accumulated attachment) from 0.42 to 0.27. The short-term incubation with IFN-gamma tended to increase the accumulated attachment (from 5.0 to 5.7 particles/AM) and decreased the ingested fraction (from 0.42 to 0.34) in unloaded AM. Long-term incubation with IFN-gamma markedly impaired both the accumulated attachment (to 3.8 particles/AM) and the ingested fraction (to 0.24) in unloaded AM and the carbon load further decreased the accumulated attachment to 2.8 particles/AM, and the ingested fraction to 0.21. The oxidative metabolism was not effected by the ingested carbon or the short-term incubation with IFN-gamma, but the long-term incubation with IFN-gamma increased it with a factor of almost 3. Our results suggest that ingested environmental particles in AM may markedly impair their phagocytic capacity, especially during long-term exposure to IFN-gamma as after infections, and there might be an increased risk for additional infections. Moreover, during an episode of high ambient particle concentration the inhaled particles will not be efficiently phagocytized and may thereby damage the Lung tissue.
Article
The authors assessed the acute association between particulate air pollution and mortality among subjects suffering from chronic obstructive pulmonary disease by using a case-crossover analysis. This design avoided the common concerns about the methods used to assess the acute effects of air pollution. The 1, 845 men and the 460 women included were residents of Barcelona, Spain, who were over age 35 years, had died during the period 1990–1995, and had visited emergency rooms because of a chronic obstructive pulmonary disease exacerbation during the period 1985–1989. Particle levels (measured as black smoke at the city monitoring stations) were associated with mortality for all causes (odds ratio (OR) for an increase of 20 μ/m3, the interquartile change, adjusted for temperature, humidity, and influenza = 1.112, 95 percent confidence interval (CI): 1.017, 1.215). The association was stronger for respiratory causes (OR = 1.182, 95 percent CI: 1.025, 1.365), but was not significant for cardiovascular causes (OR = 1.077, 95 percent CI: 0.917, 1.264). Older women, patients admitted to intensive care units, and patients with a higher rate of emergency room visits were at greater risk of dying associated with black smoke. The results reinforced the deleterious role of urban pollution and provided information on factors possibly conferring susceptibility to the acute role of air pollution.Am J Epidemiol 2000; 151:50-6.
Article
To assess whether the association between SO(2) and daily deaths in Philadelphia during the years 1974-88 is due to its correlation with airborne particles, and vice versa. There is a significant variation in the relation between total suspended particulate (TSP) and SO(2) in Philadelphia by year and season. Firstly, 30 separate regressions were fitted for each pollutant in the warm and cold season of each year. These regressions controlled for weather, long term temporal patterns, and day of the week. Then a meta-regression was performed to find whether the effect of SO(2) was due to TSP, or vice versa. Controlling for TSP, there was no significant association between SO(2) and daily deaths. By contrast, in periods when TSP was less correlated with SO(2), its association with daily deaths was higher. However, all of the association between TSP and daily deaths was explained by its correlation with extinction coefficient, a measurement of the scattering of light by fine particles, which has been shown to be highly correlated with fine combustion particles in Philadelphia. The association between air pollution and daily deaths in Philadelphia is due to fine combustion particles, and not to SO(2).
Ingested aggregates of ultra7ne carbon particles and interferon-gamma impair rat alveolar macrophage function Air pollution, lagged effects of temperature, and mortality: The Netherlands
  • M Lundborg
  • A Johannson
  • L Lastbom
  • P Camner
Lundborg, M., Johannson, A., Lastbom, L., and Camner, P. (1999). Ingested aggregates of ultra7ne carbon particles and interferon-gamma impair rat alveolar macrophage function. Environ. Res. 81, 309}315. Mackenbach, J. P., Looman, C. W., and Kunst, A. E. (1993). Air pollution, lagged effects of temperature, and mortality: The Netherlands, 1979}1987. J. Epidemiol. Commun. Health 47, 121}126.
Air pollution and hospital admissions for the elderly in Detroit, Michigan
  • Schwartz
Winter mortality and cold stress in Ekaterinburg, Russia: Interview study
  • Donaldson
Air pollution and daily mortality in Erfurt, east Germany, 1980–1989
  • Spix
Cold-induced increases in erythrocyte count, plasmacholesterol and plasma fibrinogen of elderly peoplewithout a comparable rise in protein C or Factor X
  • Neild