Prevalence of Immediate-Type Food Allergy in Early Childhood in Seoul

PURPOSE: There are scanty epidemiologic data on the prevalence of food allergy (FA) among preschool children in Asia. We performed this study to determine the prevalence and causative foods of immediate-type FA in early childhood in Korea. METHODS: A questionnaire-based, cross-sectional study was performed between September and October 2011. Children aged 0-6 years were recruited from 301 public child care centers in Seoul. Parents were asked to complete a questionnaire on FA. Children with FA were classified into "perceived FA, ever," "immediate-type FA, ever," and "immediate-type FA, current" according to the algorithm. RESULTS: A total of 16,749 children were included in this study. The prevalence of "perceived FA, ever," "immediate-type FA, ever," and "immediate-type FA, current" was 15.1%, 7.0%, and 3.7%, respectively. "Immediate-type FA, current" was reported by 182 (4.9%) out of 3,738 children aged ≤2 years, 262 (3.4%) of 7,648 children aged 3-4 years, and 177 (3.3%) of 5,363 children aged 5-6 years. Hen's egg (126/621) was the most frequent cause as the individual food item, followed by cow's milk (82/621) and peanut (58/621). Among the food groups, fruits (114/621), tree nuts (90/621) and crustaceans (85/621) were the most common offending foods. The three leading causes of food-induced anaphylaxis were hen's egg (22/47), cow's milk (15/47), and peanut (14/47). CONCLUSIONS: The prevalence of immediate-type FA in early childhood is 3.7%, and is higher in younger children. The most common offending foods differed with age.