Weather-Related Mortality: How Heat, Cold, and Heat Waves Affect Mortality in the United States

Environmental Engineering Program, Yale University, New Haven, CT, USA.
Epidemiology (Cambridge, Mass.) (Impact Factor: 6.2). 02/2009; 20(2):205-13. DOI: 10.1097/EDE.0b013e318190ee08
Source: PubMed


Many studies have linked weather to mortality; however, role of such critical factors as regional variation, susceptible populations, and acclimatization remain unresolved.
We applied time-series models to 107 US communities allowing a nonlinear relationship between temperature and mortality by using a 14-year dataset. Second-stage analysis was used to relate cold, heat, and heat wave effect estimates to community-specific variables. We considered exposure timeframe, susceptibility, age, cause of death, and confounding from pollutants. Heat waves were modeled with varying intensity and duration.
Heat-related mortality was most associated with a shorter lag (average of same day and previous day), with an overall increase of 3.0% (95% posterior interval: 2.4%-3.6%) in mortality risk comparing the 99th and 90th percentile temperatures for the community. Cold-related mortality was most associated with a longer lag (average of current day up to 25 days previous), with a 4.2% (3.2%-5.3%) increase in risk comparing the first and 10th percentile temperatures for the community. Mortality risk increased with the intensity or duration of heat waves. Spatial heterogeneity in effects indicates that weather-mortality relationships from 1 community may not be applicable in another. Larger spatial heterogeneity for absolute temperature estimates (comparing risk at specific temperatures) than for relative temperature estimates (comparing risk at community-specific temperature percentiles) provides evidence for acclimatization. We identified susceptibility based on age, socioeconomic conditions, urbanicity, and central air conditioning.
Acclimatization, individual susceptibility, and community characteristics all affect heat-related effects on mortality.

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    • "elderly in the population. The expected increase in the number of elderly and other potentially vulnerable groups, in absolute numbers and as a proportion of the population, could make the impact of temperature extremes on human health more severe (Sierra et al. 2009), because the elderly and chronically ill are more sensitive to temperature extremes (Anderson and Bell 2009; Basu 2009; Oudin Åström et al. 2011). "
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    • "D. Phung et al. / Environmental Pollution xxx (2015) 1e7 5 Please cite this article in press as: Phung, D., et al., The effects of high temperature on cardiovascular admissions in the most populous tropical city in Vietnam, Environmental Pollution (2015), Anderson and Bell, 2009; Kolb et al., 2007) and years of life lost due to CVD (Huang et al., 2012a) but studies of the relationship between high temperature and CVD admissions have provided inconsistent findings. Our study has supported the hypothesis of the positive association between high temperatures and cardiovascular admissions that was reported in some previous studies (Konken et al., 2003; Lin et al., 2009; Schwartz et al., 2004). "
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