Outdoor Temperature Change and Emergency Department Visits in 7 cities, Korea: A Case-Crossover Study

The objective of this study is to characterize the effect of temperature on number of ED visits including specified cause of visit such as heat related disease; heatstroke, myocardial infarction, ischemic heart disease in major cities, Korea.
We conducted a case-crossover study to determine whether the association between temperature and ED visits for heat related disease varies by season or month among 7 major cities’; Seoul, Busan, Daegu, Incheon, Gwangju, Daejeon and Ulsan using a National Emergency Department Information System. The associations between temperature and ED visits for the all visits have positive significance when the overall association is examined at each city ; Seoul (OR=1.011, 95%CI:1.010,1.011), Busan (OR=1.010, 95%CI:1.008,1.011), Daegu (OR=1.006, 95%CI:1.005,1.007), Incheon (OR=1.014, 95%CI:1.013-1.015), Gwangju (OR=1.015, 95%CI:1.013,1.016), Daejeon (OR=1.010, 95%CI:1.009,1.011), and Ulsan (OR=1.010, 95%CI:1.009,1.012). However, seasonal, monthly, and cause of ED visits’ variations were detected among the cities. The association of Heatstroke ED visits and temperature was significant in several cities but there exists monthly variation among cities.In the future, preventive measures must be taken to limit the health consequences of uncertain temperature increase such as heat waves to come.