A vulnerability study of the low-income elderly in the context of high temperature and mortality in Seoul, Korea

IntroductionWe investigated the impact of environmental high temperature on mortality in Seoul, Korea, and the consequences of high temperature-induced mortality with a focus on the low-income elderly.MethodsChanges in the risk of death by age and income were estimated by a 1 °C increase in temperature using a generalized additive model adjusting for non-temperature related factors: time trends, seasonality, and air pollution. The study covered the years of 2000, 2001, and 2002.ResultsWe found that income and age were potential factors in high-temperature-induced excess mortality. Evidences to support these results are as follows: first, regarding the effect of an economic factor in the association between mortality and high temperature, the study shows that the mortality rate of the low-income group is higher, by as much as 1.3- to 1.7-fold, than that of the general population. Second, taking age into consideration, the mortality of low-income elderly people is 1.5-fold higher than that of the whole low-income group. The combined effect of income and age on mortality is estimated as 2.3-fold higher than that of the general population. But the results of the low-income and elderly group were not statistically significant due to wide standard deviation.ConclusionsThe relationship between high-temperature-induced excess mortality, income, and age suggests the need for a public health message, yet many results were not statistically significant: preventive and health care interventions need to be administered to the elderly and low-income group during periods of high temperature.