The incidence of type 1 diabetes in Republic of Srpska (Bosnia and Herzegovina) and Slovenia in the period 1998-2010

Abstract

To establish and compare the incidence and trends of type 1 diabetes mellitus (T1DM) in Republic of Srpska and Slovenia in age group 0-18 yr from 1998 to 2010. The subjects (413 newly diagnosed T1DM patients in the Republic of Srpska and 664 in Slovenia) were grouped into the age groups: 0-4, 5-9, 10-14, and 15-18 yr. Confidence intervals (CI) for crude incidence rates were estimated assuming numbers of cases were counts from the Poisson distribution. Gender and age-specific standardization was done according to the EURODIAB criteria. Statistical analysis used Poisson-regression models to analyze difference rate between countries and to investigate the incidence trend. Case ascertainment was estimated to be 99.95% for the Republic of Srpska and 100% for Slovenia by using the capture-recapture method. The standardized incidence of T1DM for age group 0-18 yr in the Republic of Srpska was 7.5/100 000/yr (95% CI: 6.8-8.3). For the same period and the same age group incidence in Slovenia was 12.5/100 000/yr (95% CI: 11.5-13.5). Annual increase in the incidence in the Republic of Srpska was 2.3% (95% CI: -0.3 to 5.0%), whereas in Slovenia 4.3% (95% CI: 2.2-6.5%). The incidence for age group 0-18 yr standardized to the world population is remarkably higher in Slovenia than in the Republic of Srpska. Further follow-up and investigations are needed to explain the high difference in incidence of T1DM between the two geographically related countries.