Self-reported adverse food reactions and anaphylaxis in the SchoolNuts study: A population-based study of adolescents

Background: Adolescents are at the highest risk of death from anaphylaxis, yet few population-based studies have described the frequencies and risk factors for allergic reactions caused by accidental allergen ingestion in this group. Methods: We describe the prevalence, frequency, and associated risk factors for recent adverse food reactions in 10-to 14-year-olds in Melbourne, Australia, recruited from a stratified, random, population-based sample of schools (SchoolNuts, n = 9663; 48% response rate). Self-reported food allergy and adverse reaction details, including anaphylaxis, were identified by using a student questionnaire over the past year. Results: Of 547 students with possible IgE-mediated food allergy, 243 (44.4%; 95% CI, 40.3% to 48.7%) reported a reaction to a food. Fifty-three (9.7%; 95% CI, 7.2% to 12.2%) students reported 93 anaphylaxis episodes. Peanut and tree nuts were the most common food triggers. Among students with current IgE-mediated food allergy, those with resolved or current asthma (adjusted odds ratio [aOR], 1.9 [95% CI, 1.1-1.3] and 1.7 [95% CI, 1.1-2.6]) and those with more than 2 food allergies (aOR, 1.9 [95% CI, 1.1-3.1]) were at greatest risk of any adverse food reaction, and those with nut allergy were most at risk of severe reactions (aOR, 2.9 [95% CI, 1.1-4.4]). Resolved or current asthma was not associated with increased risk of severe reactions (aOR, 0.8 [95% CI, 0.3-2.2] and 1.6 [95% CI, 0.7-3.7]). Conclusions: Adolescents with food allergy are frequently exposed to food allergens. Those with asthma and more than 2 food allergies were at the greatest risk for adverse food reactions. Those with nut allergies were most at risk of severe reactions.