Early infant feeding and risk of developing type 1 diabetes-associated autoantibodies

Abstract

Context: Dietary factors modifying type 1 diabetes mellitus (DM) risk have been proposed, but little is known if they trigger the islet autoimmunity that precedes clinical disease.

Objective: To determine whether breastfeeding duration, food supplementation, or age at introduction of gluten-containing foods influences the risk of developing islet autoantibodies.

Design and setting: Prospective natural history cohort study conducted from 1989 to 2003 in inpatient/outpatient clinics in Germany.

Participants: The BABYDIAB study follows newborn children of parents with type 1 DM. Eligibility requirements were met in 1610 children. Blood samples were obtained at birth, age 9 months, 2, 5, and 8 years. Dropout rate was 14.4% by age 5 years. Breastfeeding data were obtained by prospective questionnaires (91% complete), and food supplementation data were obtained by family interview (72% for food supplementation and 80% for age of gluten introduction).

Main outcome measure: Development of islet autoantibodies (insulin, glutamic acid decarboxylase, or IA-2 antibodies) in 2 consecutive blood samples.

Results: Life-table islet autoantibody frequency was 5.8% (SE, 0.6%) by age 5 years. Reduced total or exclusive breastfeeding duration did not significantly increase the risk of developing islet autoantibodies. Food supplementation with gluten-containing foods before age 3 months, however, was associated with significantly increased islet autoantibody risk (adjusted hazard ratio, 4.0; 95% confidence interval, 1.4-11.5; P =.01 vs children who received only breast milk until age 3 months). Four of 17 children who received gluten foods before age 3 months developed islet autoantibodies (life-table 5-year risk, 24%; SE, 10%). All 4 children had the high-risk DRB1*03/04,DQB1*0302 genotype. Early exposure to gluten did not significantly increase the risk of developing celiac disease-associated autoantibodies. Children who first received gluten foods after age 6 months did not have increased risks for islet or celiac disease autoantibodies.

Conclusion: Ensuring compliance to infant feeding guidelines is a possible way to reduce the risk of development of type 1 DM autoantibodies.