[Incidence of insulin-dependent diabetes mellitus in the metropolitan region].

We used a retrospective search and confirmation method to establish the number of new cases of insulin dependent diabetes mellitus diagnosed between Jan 1, 1986 and Dec 31, 1989 in subjects under 15 years of age in the Metropolitan region of Chile. All hospitals and outpatient facilities of the National Health Service, other hospitals and private offices of endocrinologists and specialists in diabetes were surveyed, as well as the registry from the Juvenile Diabetes Foundation. A total of 115 cases, 52 in males and 63 in females were found, for an annual incidence of 1.69 and 2.15 per 100,000, respectively. Overall, the annual incidence rates were 2.22 in 1986, 1.22 in 1987 (p < 0.001), 2.13 in 1988 and 2.09 in 1989. A greater number of cases was diagnosed at age 4 in males and at age 12 in females (p < 0.001). The greater number of cases were diagnosed from June to August (winter) and the lowest in October (p < 0.001).