Korean J Epidemiol.
1995 Jun;17(1):64-75.
Asthma and Air Pollution in Korea
Abstract
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With rapid industrialization and urbanization, environmental pollution has become an urgent health problem. Asthma attack is a common and severe disease, and can be a sentinel event of worsening air pollution. There are, however, few studies about the epidemiolgy of asthma and the association between asthma and low level air pollution in Korea. This study was conducted to describe the trend and pattern of asthma attack and to examine the effect of air pollutants on admission in Korea. Combined data of this study are medical insurance claims for asthma, data from telemetry system of the Ministry of Environment for air pollutants, and air temperatures from monthly weather reports of the Meteorological Administration. To describe the temporal trends of asthma in Korea, insurance claims since 1985 were analized. Age specific asthma visit/admissions per 1000 eligible persons, as well as ratio of asthma visit/admissions over all visit/admissions showed a steady increase in asthma attack in Korea. Asthma prevalence was relatively high among under 5 years and over 50 years of age, and in these age groups asthma was more prevalent among males. The effects of relatively low level air pollution and weather condition on the number of patients who had asthma attacks admitted to hospitals in Seoul area were studied from April 2 to April 24, 1993. Asthma admissions were examined throughout the study period (392 cases), except sunday and holiday(354 cases) and except sunday, holiday and saturday (293 cases), while grouped into three age categories (3 12, over 40, and all age). Following results were obtained through correlation and multiple regression analysis. The number of adimission were significantly correlated with ambient air concentrations of total suspended particles (TSP), sulfur dioxide (SO2) and carbon monoxide(CO). 1) The number of admissions on the same day were significantly correlated with ambient air maximal concentrations of total suspended particcles among persons who were above 40 year old. 2) The effects of maximal daily concentrations of sulfer dioxide(SO2) among persons who were of 3- 12 age were significant when one day lagged asthma admission was compared with the air pollution on the previous day. 3) The number of admissions on 1-day lag were significantly correlated with ambient air maximal daily concentrations of carbon monoxide(CO) among persons who were above 40 year old. The associations between temperatures and number of admissions were not significant in this study. Levels of pollutants were fairly low, the monthly mean being 0.022 ppm for SO2, 0.032 ppm for NO2, 3.2 ppm for CO, 0.015 ppm for 03, and 240 micro gram/m3 for TSP. The mean temperature was 10.6degrees C. These results suggest that concentration of air pollutants lower than those given as guidelines may increase the incidence of asthma attacks.