Abstract
We have compared the incidence of Type 1 diabetes in childhood between two predominantly Russian populations from the former Soviet Union-the non-Estonians living in Estonia and the inhabitants of the district of Novosibirsk. The study period covered the years 1980–1989 for the non-Estonians and 1983–1989 for the district of Novosibirsk. The mean annual incidence of Type 1 diabetes was significantly higher in the non-Estonian population, 7.8 per 100000(95% confidence interval (CI): 6.3–9.6) than in Novosibirsk where it was 4.7 per 100000(95% CI: 4.1–5.4). The highest incidence in females from Estonia was in the age group 5–9 years and in Novosibirsk 10–14 years. In the youngest age group of 0–4 years there was no difference in the incidence between non-Estonians in Estonla and the population of Novosibirsk, or males and females in either population. There was no difference in the incidence between the 0–4 and 5–9 year age groups in Novosibirsk males. No time trend was seen in the incidence over the study period in either population. The annual incidence in Novosibirsk was fairly stable, while in the non-Estonians it showed two distinct peaks. The most likely reason for the observed phenomena is a different pattern and higher prevalence of environ mental causal agents in the Baltic country of Estonia.