Infections and risk of Type I (insulin-dependent) diabetes mellitus in Lithuanian children

Aims/hypothesis. The role of infections in the aetiology of Type I diabetes is controversial. Certain enteroviral infections might be involved in trig gering the beta-cell destruction but insufficient exposure to early infecti ons might increase the risk. We studied how the number of infections experi enced during several periods from birth to onset influence diabetes risk. Methods. The study group came from the five largest Lithuanian cities: 124 patients, selected from the 0-14 years-of-age childhood diabetes register a nd 372 population-based control subjects matched with them for age group an d sex. Information about infections and duration of breastfeeding was colle cted from health care booklets, other data from a mailed questionnaire, ret urned by 94.4% of patients and 72.6 % of control subjects. Results. One or more infections experienced during the first half year of l ife tended to reduce diabetes risk. Crude odds ratios (95% confidence inter vals) in the 0-14, 0-4 and 5-14 years-of-age groups were 0.66 (0.42-1.04), 1.06 (0.48-2.36) and 0.52 (0.30-0.90) respectively. Adjustment for the dura tion of breastfeeding, number of people in the household, duration of mothe r's education and birth order of the index child made little difference. Od ds ratios (95 % confidence intervals) in the 0-14, 0-4 and 5-14 years-of-ag e groups were 0.60 (0.37-0.98), 0.94 (0.40-2.20) and 0.47 (0.26-0.87), resp ectively. The number of infections recorded during the last preonset year o r from birth to onset did not influence diabetes risk. Conclusion/interpretation. Exposure to infections early in life could decre ase diabetes risk, particularly for children diagnosed after the age of 4 y ears.