Influence of early-life exposures on food sensitization and food allergy in an inner-city birth cohort

• DOI: 10.1016/j.jaci.2014.06.033
• Publication Date: 2014-08-13T16:22:59Z
• Authors: Emily C. McGowan; Gordon R. Bloomberg; Peter J. Gergen; Cynthia M. Visness; Katy F. Jaffee; Megan Sandel; George O'Connor; Meyer Kattan; James Gern; Robert A. Wood
• Keywords: Male; Cohort Studies; 03 medical and health sciences; 0302 clinical medicine; 11. Sustainability; Prevalence; Humans; Peanut Hypersensitivity; Cities; Egg Hypersensitivity; Infant; Dust; Environmental Exposure; Health Status Disparities; Allergens; Immunoglobulin E; United States; 3. Good health; Child, Preschool; Immunoglobulin G; Housing; Cytokines; Female; Milk Hypersensitivity

Previous data suggest that food allergy (FA) might be more common in inner-city children; however, these studies have not collected data on both sensitization and clinical reactivity or early-life exposures.Children in the Urban Environment and Childhood Asthma birth cohort were followed through age 5 years. Household exposures, diet, clinical history, and physical examinations were assessed yearly; levels of specific IgE to milk, egg, and peanut were measured at 1, 2, 3, and 5 years of age. On the basis of sensitization (IgE ≥0.35 kU/L) and clinical history over the 5-year period, children were classified as having FA or being possibly allergic, sensitized but tolerant, or not allergic/not sensitized.Five hundred sixteen children were included. Overall, 55.4% were sensitized (milk, 46.7%; egg, 31.0%; and peanut, 20.9%), whereas 9.9% were categorized as having FA (peanut, 6.0%; egg, 4.3%; and milk, 2.7%; 2.5% to >1 food). The remaining children were categorized as possibly allergic (17.0%), sensitized but tolerant (28.5%), and not sensitized (44.6%). Eighteen (3.5%) reported reactions to foods for which IgE levels were not measured. Food-specific IgE levels were similar in children with FA versus sensitized but tolerant children, except for egg, levels of which were higher in patients with FA at ages 1 and 2 years. FA was associated with recurrent wheeze, eczema, aeroallergen sensitization, male sex, breast-feeding, and lower endotoxin exposure in year 1 but not with race/ethnicity, income, tobacco exposure, maternal stress, or early introduction of solid foods.Even given that this was designed to be a high-risk cohort, the cumulative incidence of FA is extremely high, especially considering the strict definition of FA that was applied and that only 3 common allergens were included.