Incidence and trends of childhood Type 1 diabetes in Croatia from 1995 to 2003

Abstract

Aims/hypothesis: The aim of this study was to examine incidence and trends of Type 1 diabetes in children aged 0-14 years in Croatia from 1995 to 2003.

Methods: The incidence data were obtained from two sources. The incidence was calculated as the number of newly diagnosed Type 1 diabetes patients per 100,000 person-years for the age group 0-14 years, and subgroups 0-4, 5-9, and 10-14 years. Standardized incidence was calculated using the method of direct standardization to the world standard population for the age group 0-14 years. The ascertainment was estimated with capture-recapture method. Trends in the incidence of Type 1 diabetes for period from 1995 to 2003 in Croatia were analyzed using Poisson regression model.

Results: The standardized incidence of Type 1 diabetes for the whole age group was 8.87 per 100,000 person-years (95% CI: 5.07-12.68), for girls 8.47 (95% CI: 7.54-9.41) and for boys 9.26 (95% CI: 8.30-10.21). During the studied period, the trend in incidence raised significantly for the whole age group (chi(2)=32.6, p<0.001). The average annual increase in incidence was 9% (95% CI: 5.8-12.2).

Conclusions/interpretation: This rate of incidence places Croatia in a group of countries with moderate risk for development of Type 1 diabetes. The average annual increase in incidence of 9% is markedly higher than in most European countries, and probably reflects lifestyle changes upon economic recovery of the country.