Brief communication: early appearance of islet autoantibodies predicts childhood type 1 diabetes in offspring of diabetic parents.

Abstract

The development of type 1 diabetes mellitus is preceded by autoimmunity against islet beta cells. To determine the risk for islet autoimmunity and childhood diabetes in offspring of affected parents. Prospective cohort study. German BABYDIAB study. 1610 offspring of parents with type 1 diabetes. Autoantibodies to islet autoantigens were measured at 9 months, 2 years, 5 years, and 8 years of age. By 5 years of age, the frequency of islet autoantibodies was 5.9% (95% CI, 4.6% to 7.2%), the frequency of multiple islet autoantibodies was 3.5% (CI, 2.5% to 4.5%), and the frequency of diabetes was 1.5% (CI, 0.9% to 2.1%). The risk for diabetes was highest in offspring with multiple autoantibodies (40% within 5 years vs. 3% in offspring with single autoantibodies; P = 0.005). Progression to multiple islet autoantibodies was fastest in children who were autoantibody positive by age 2 years (P < 0.001), and progression to diabetes was inversely related to the age of positivity for multiple autoantibodies (P = 0.02). The findings are limited to childhood diabetes in affected families. Childhood autoimmune diabetes is associated with autoimmunity that starts before 2 years of age.