Heat-Attributable Deaths between 1992 and 2009 in Seoul, South Korea

<div><p>Background</p><p>Climate change may significantly affect human health. The possible effects of high ambient temperature must be better understood, particularly in terms of certain diseases’ sensitivity to heat (as reflected in relative risks [RR]) and the consequent disease burden (number or fraction of cases attributable to high temperatures), in order to manage the threat.</p><p>Purpose</p><p>This study investigated the number of deaths attributable to abnormally high ambient temperatures in Seoul, South Korea, for a wide range of diseases.</p><p>Method</p><p>The relationship between mortality and daily maximum temperature using a generalized linear model was analyzed. The threshold temperature was defined as the 90^th percentile of maximum daily temperatures. Deaths were classified according to ICD-10 codes, and for each disease, the RR and attributable fractions were determined. Using these fractions, the total number of deaths attributable to daily maximum temperatures above the threshold value, from 1992 to 2009, was calculated. Data analyses were conducted in 2012–2013.</p><p>Results</p><p>Heat-attributable deaths accounted for 3,177 of the 271,633 deaths from all causes. Neurological (RR 1.07; 95% CI, 1.04–1.11) and mental and behavioral disorders (RR 1.04; 95% CI, 1.01–1.07) had relatively high increases in the RR of mortality. The most heat-sensitive diseases (those with the highest RRs) were not the diseases that caused the largest number of deaths attributable to high temperatures.</p><p>Conclusion</p><p>This study estimated RRs and deaths attributable to high ambient temperature for a wide variety of diseases. Prevention-related policies must account for both particular vulnerabilities (heat-sensitive diseases with high RRs) and the major causes of the heat mortality burden (common conditions less sensitive to high temperatures).</p></div

Descriptive Statistics of meteorological variables (1992–2009) and air pollutants (2001–2009).

<p>Descriptive Statistics of meteorological variables (1992–2009) and air pollutants (2001–2009).</p

Estimated relative risk of mortality for every 1°C increase in temperature above the 29.5°C threshold from May through September, 1992–2009.

<p>Estimated relative risk of mortality for every 1°C increase in temperature above the 29.5°C threshold from May through September, 1992–2009.</p

Estimating the incidence of novel influenza A (H1N1) by age group and region during September to December 2009 in Korea.

<p><b>NOTE</b>. Incidence  =  no. of each cases ÷ population of each age group.</p>†<p>All patients registered in the Antiviral Drug Surveillance System (ADSS) were confirmed or suspected to have the infection.</p

Multivariate behavioral predictors associated with a severe outcome in relation to a nonsevere outcome among all cases.

<p><b>NOTE.</b>^†current smokers.</p>‡<p>drink more than once or twice per week.</p

Estimated number of deaths attributable to heat and estimated relative risk of mortality for a 1°C increase in temperature above the threshold temperature (29.5°C).

<p>^a Attributable death / Number of death from specific causes: Proportion of attributable death to each cause of death.</p><p>^b Attributable death / Total number of death: Proportion of attributable deaths to total number of death.</p><p>Estimated number of deaths attributable to heat and estimated relative risk of mortality for a 1°C increase in temperature above the threshold temperature (29.5°C).</p

Multivariate factors associated with a severe outcome in relation to a nonsevere outcome among all antiviral drug users.

<p><b>NOTE</b>. Odds ratios (ORs) were adjusted with eight categories of underlying disease.</p>†<p>Results for multivariate logistic regression without considering the various underlying diseases.</p

Baseline characteristics of the body mass index (BMI) subset.

<p><b>NOTE.</b>^†current smoker.</p>‡<p>drink more than once or twice per week.</p

Epidemic curves of confirmed or suspected influenza A (H1N1) (A) and confirmed only (B).

<p>Proportion of severe outcomes among confirmed or suspected influenza A (H1N1) cases by age group (C) and confirmed cases only (D).</p

Generation of runaway electron beams and x-rays in high pressure gases

<p><b>The relative risks (RRs) of cardiovascular disease per one-interquartile range increase in elemental carbon (EC) (A) or organic carbon (OC) (B) for each age group and sex on lag 0 day.</b> CI: confidence interval.</p