The change in food allergy prevalence of elementary school children in Seoul since the last 20 years and the risk factor analysis

Purpose: There are many reports that the prevalence of food allergy (FA) is globally increasing. We investigated the change in FA prevalence since the last 20 years in elementary school children, in Seoul, Korea. Methods: A modified International Study of Asthma and Allergies in Childhood questionnaire survey was done to elementary school children in Seoul, Korea in 1995, 2000, 2005, 2008, and 2012. The numbers of subjects included in the analysis were 7,963, 7,971, 7,131, 3,975, and 3,307, respectively. Blood and skin prick tests were done in 2008 and 2012. Results: The prevalence rates of FA diagnosis ever were 4.6% (95% confidence interval [CI], 4.1-5.1), 5.2% (95% CI, 4.7-5.7), 6.4% (95% CI, 5.9-7.0), 5.5% (95% CI, 4.8-6.3), and 6.6% (95% CI, 5.8-7.6) in 1995, 2000, 2005, 2008, and 2012, respectively (P-value for trend < 0.001). Asthma (adjusted odds ratio [aOR], 2.209; 95% CI, 1.589-3.072), allergic rhinitis (aOR, 1.874; 95% CI, 1.473-2.384), and atopic dermatitis (aOR, 4.288; 95% CI, 3.340-5.506) were associated with FA diagnosis. Parental allergic disease history (aOR, 2.191; 95% CI, 1.666-2.881), antibiotics use in infancy (aOR, 1.484; 95% CI, 1.170-1.883), and house mold exposure in infancy (aOR, 1.540; 95% CI, 1.172-2.024) were risk factors for FA diagnosis. Sensitization to inhalant allergens (aOR, 1.867; 95% CI, 1.091-3.194) and increased serum total IgE (aOR, 2.014; 95% CI, 1.081-3.752) were associated with FA diagnosis. Conclusion: The prevalence of FA diagnosis is likely to be increasing since the last 20 years in Seoul. Antibiotics use in infancy and house mold exposure in infancy were risk factors for FA diagnosis.