Prevalence and ten-year (1970-1979) incidence of insulin-dependent diabetes mellitus in children and adolescents in Finland.

The prevalence and incidence of insulin-dependent diabetes mellitus in Finnish children and adolescents were studied by means of a national register of drug-treated diabetics and hospital records. At the end of 1979 the prevalence of diabetes in children aged 0-14 was 191/100 000, and in those aged 0-19, 262/100 000 respectively. During the 10-year period from 1970 to 1979, 3916 new diabetics aged 0-19 years were registered. The annual incidence of diabetes was 27.3/100 000 in the age group 0-19 years and 28.6/100 000 in those 0-14 years. The peak incidence of diabetes in girls occurred at 12 years of age and in boys at 14 years. There was a seasonal variation in the symptom debut, with peaks in April and in September and low rates in the summer. A regional variation in the prevalence and incidence rates was evident the rates being highest in eastern and lowest in northern Finland. The prevalence of diabetes mellitus increased clearly during the observation period, and the incidence tended to increase especially during the last years. Both prevalence and incidence rates of diabetes mellitus in Finnish children are high by international standards, possibly the highest in the world.