Meteorological conditions and sports deaths at school in Japan, 1993-1998.

We evaluated the association between meteorological conditions and sports deaths at elementary, junior high and senior high schools. Data were collected from attached documents such as accident reports and death certificate records in the National Agency for the Advancement of Sports and Health in Japan. Evaluation of seasonal variation showed a significant concentration of deaths from heat disorders and drowning in July and August. When heart disease was evaluated according to the sports situation, significant seasonal variation with a high number of deaths in September-December was observed in sports events. Concerning circadian variation, deaths from heart disease showed a high peak at 10:00-11:00 a.m. in physical education classes and sports events, and at 2:00-5:00 p.m. in sports club activities. Analysis using a multiple logistic model showed a significantly lower odds ratio from heart disease and a significantly higher odds ratio from heat disorders at a wet bulb globe temperature of > or =21.0 degrees C than at <21.0 degrees C. According to the sports situation in heart disease, the odds ratio in sports club activities was significantly lower on days with rainfall than on days without rainfall. According to the school categories in heart diseases, the odds ratio in girls in elementary school was significantly higher than that in boys, but the odds ratio in girls in senior high school was significantly lower than that in boys.