Incidence of type I diabetes in the Liguria Region, Italy. Results of a prospective study in a 0- to 14-year age-group

Abstract

Objective: To assess updated incidence of insulin-dependent diabetes mellitus (IDDM) in 0- to 14-year-old children in Liguria, a northwest region of Italy.

Research design and methods: Incident cases were recorded prospectively from 1987 to 1991. Incidence rates (IRs) were directly standardized on the basis of the 1990 world population. The independent effect of age, sex, residence, and calendar year was estimated with a Poisson regression model. The degree of ascertainment was calculated in accordance with the capture/recapture method.

Results: During 5 full calendar years, 117 new cases of IDDM in children were diagnosed in Liguria. The standardized IR over the 5-year period was 11.72 cases.100,000(-1).year-1. The sex-specific IR among males and females was 11.45 and 12.01, respectively. The age-specific IR was higher in the 5-9 age-group.

Conclusions: The IR of IDDM in Liguria is among the highest in southern Europe and approaches that of northern European countries. In particular, it is much higher than those reported in the surrounding Italian regions, except for Sardinia. Therefore, the geographical distribution of IDDM does not seem to reflect the simple north-south gradient reported in several previous studies.