Incidence of Type 1 diabetes mellitus in children aged 0-14 in Japan. 1986-1990, including an analysis for seasonality of onset and month of birth: JDS study

Aims To detect the incidence of childhood Type 1 diabetes mellitus (DIM) (0 -14 years) in Japan and to find out whether there is a seasonal pattern in the onset of disease and month of birth of children with diabetes. Methods Ascertained data for the period 1986-1990 could be collected in 35 out of 47 local government areas representing 69.4% of the childhood popula tion (aged 0-14 years) of japan. Results A total of 1260 children with Type 1 DM were identified (738 girls, 522 boys). With age there was a progressive increase in incidence from 0.7 to 2.1/10(5) in boys and from 0.6 to 3.5/10(5) in girls. With the exceptio n of 1987, when a coxsackie B3 virus epidemic was registered, no seasonal v ariation in the month of onset was observed, nor was a seasonal pattern of the month of birth registered in this cohort. Conclusions Compared to European countries, the USA and Israel, the Japanes e cohort of children with diabetes presents the following differences: the incidence is much lower, there is a preponderance of girls and there is (wi th one exception) no seasonal pattern.