Prevalence and Characteristics of Multifood Allergy among US Children with Food Allergy

IgE-mediated food allergy (FA) currently affects millions of US children, leading to impaired quality of life resulting from avoidance of allergenic foods—with greater impairment observed among patients allergic to multiple foods (i.e. “multi-FA”). However, little is known about the current prevalence of multi-FA and specific patterns of co-occurring FAs among US children of different ages. Parent-proxy FA surveys were completed for a nationally representative sample of 38,408 US children between October 2015 and September 2016. Multi-FA was evaluated in children with parent-reported FA meeting strict symptom-report criteria (i.e. “convincing FA”). Among all children with parent-reported FA, 53.1% (95% CI: 49.8%-56.4%) reported multi-FA compared to 39.9% (95% CI: 36.8%-43%) with convincing multi-FA. With respect to convincing multi-FA, among children with peanut allergy, 33.1% had tree nut co-allergy and 61% of those with tree nut allergy had peanut co-allergy. In addition to tree nut (29.3%), egg (25.4%) and milk (24.6%) allergies were common in peanut-allergic children aged 0-2 years. Among all children with sesame allergy, 55.2% and 43.9% had peanut and tree nut co-allergy, respectively. No particularly common co-allergies were identified for milk, whereas those with egg allergy frequently had milk (35.2%) and peanut (29.3%) co-allergy. Among those with shellfish allergy, peanut (25.2%) and finfish (23.8%) were the most common co-allergies. Soy and wheat allergy had different common co- allergens in different age groups. Slightly over half of US children with FA report multi-FA compared to 40% reporting convincing multi-FA. Distinct co-allergy patterns were observed by age and specific FA.