Antibiotic Exposure and the Risk of Food Allergy: Evidence in the US Medicaid Pediatric Population

BACKGROUND: Food allergy is a significant public health concern in the United States, especially in the pediatric population. It places substantial clinical and economic burdens on the health care system. Exposure to antibiotics in early childhood is thought to increase the risk of subsequent food allergy. OBJECTIVE: To examine the impact of exposure to antibiotics early in life on time to development of food allergy. METHODS: We conducted a population-based matched cohort study using Medicaid data from 28 states. Antibiotic nonusers were matched 1:1 to antibiotic users on date of birth, sex, race, and state. A Cox proportional hazards regression model was used to evaluate the effect of antibiotic exposure on time to development of food allergy. Sensitivity analyses were performed to assess the robustness of study findings. RESULTS: We matched 500,647 antibiotic nonusers to 500,647 antibiotic users in the Medicaid pediatric population. In the adjusted Cox proportional hazards regression analysis, antibiotic exposure was significantly associated with faster development of food allergy (hazard ratio, 1.40; 95% CI, 1.34-1.45). The magnitude and significance of the association between antibiotic exposure and food allergy did not change in the sensitivity analyses. A significant association between antibiotic exposure and faster development of food allergy was found in 17 of 28 states. CONCLUSION: Compared with antibiotic nonusers, children with antibiotic prescription had an increased risk of food allergy. (C) 2018 American Academy of Allergy, Asthma & Immunology