Trends of Peanut-Induced Anaphylaxis Rates Before and After the 2017 Early Peanut Introduction Guidelines in Montreal, Canada.

Abstract

Food allergies, particularly peanut, represent the predominant cause of anaphylaxis. Whereas early allergen introduction has emerged as a potential preventive strategy, the precise impact of recent guidelines on peanut-induced anaphylaxis rates in Canada remains unclear. To assess the impact of the 2017 Addendum Guidelines for the Prevention of Peanut Allergy on peanut-induced anaphylaxis rates in Canada. Using a comprehensive longitudinal registry capturing pediatric anaphylaxis presentations to the Montreal's Children's Hospital, we compared children with and without known peanut allergy who presented with peanut-induced anaphylaxis between 2011 and 2019 inclusive, excluding data beyond 2019 owing to the Coronavirus disease 2019 (COVID-19) pandemic. We calculated rates of peanut-induced anaphylaxis presentations per 100,000 age-adjusted all-cause emergency department visits using 4-month intervals. Interrupted time series analysis was used to compare anaphylaxis rate trends before and after 2017 for children ages 0 to 2 and 3 to 17 years. We examined 2,011 cases of pediatric anaphylaxis, including 429 (21%) triggered by peanuts. Compared with pre-guideline estimates, the yearly rate of change of peanut anaphylaxis rates decreased by 7.96 (95% confidence interval -14.57 to -1.36; P = .018) after 2017 among patients with new-onset anaphylaxis in children 2 years of age or younger (n = 109). No significant changes were identified for older patients ages 3 to 17, or in patients with known peanut allergy. Early introduction guidelines in Canada are associated with a reduced risk of new-onset peanut-induced anaphylaxis in young children within a single center in Montreal. Further research is required to assess the impact on a wider population and other food allergens.