Decreased prevalence of atopic diseases in children with diabetes

Objective: To test the hypothesis that atopic diseases in early life are as sociated with a reduced risk (protection) for the development of type 1 dia betes in childhood. Study design: European centers (n = 8) with access to population-based type 1 diabetes registries (>90% degree of ascertainment) participated in a cas e control study focusing on early exposures and risk factors for type 1 dia betes. Altogether data from 1028 members of a case group and 2744 members o f a control group corresponding to 85.4% eligible members of the case group and 76.1% of the control group were analyzed. Information in this study wa s collected regarding atopic diseases (atopic eczema, allergic rhinoconjunc tivitis, and asthma). Results: Atopic disease and asthma particularly are associated with signifi cant reductions in risk of childhood type 1 diabetes. The risk reduction as sociated with asthma was observed reasonably consistently among the 8 study centers, which represent a wide range of diabetes incidence. Risk reductio ns associated with all 3 expressions of atopy were particularly marked in c hildren whose type 1 diabetes was diagnosed in the 10- to 14-year age group . Conclusion: These findings indicate that atopic conditions may be protectiv e against the development of type 1 diabetes and are consistent with the im munologic concept of T(H)1 (type 1 diabetes) and T(H)2 (atopy) diseases bei ng mutually exclusive.