Diabetes incidence in children of different nationalities: an epidemiological approach to the pathogenesis of diabetes

Aims/hypothesis. Incidence studies of children with Type I (insulin-dependent) diabetes mellitus and different ethnic backgrounds are known to provide important insights into the pathogenesis of the disease. For this reason, we compared the incidence rate in Baden-Wurttemberg. Germany, of children who were not of German descent with that of German children as well as with the reported incidence rates pertaining to the countries of origin of the children who were not of German descent. Methods. Our study was based on the Baden-Wurttemberg incidence register, part of the EURODIAB TIGER network, which includes 2121 children aged 0-14 years, diagnosed as having Type I diabetes between 1987 and 1997. The study covered a population at risk of 1.8 million children, which represents 13.3% of the total number of children in Germany. Results. The total incidence rate was found to be 12.5 per 100 000 per year (95%-CI 12.0-13.0); for German children alone it was calculated as 13.5 (95%-CI 12.9-14.1) and for children who were not of German descent it was significantly lower at 6.9 per 100 000 per year (95%-Cl 5.8-8.0). The percentage of children who were not of German descent with Type I diabetes (8.3%) is smaller than that among the general population (15.2%). Children from former Yugoslavia, Italy and Greece had incidence rates closer to their countries of origin than to the incidence rate of German children. Conclusion/interpretation. Our findings indicate that genetic factors play a predominant role in the pathogenesis of Type I diabetes. However, the influence of certain aspects of life-style, which remain constant even after immigration, cannot be excluded.