Prevalence of food allergy increased 1.7 times in the past 10 years among Japanese patients below 6 years of age

Abstract

AbstractBackgroundWhile food allergy (FA) has been increasingly recognized as a growing public health burden worldwide, epidemiological studies on FA in Japan are limited.MethodsThis was a noninterventional, observational study using the administrative claims data from 2010 to 2019 (10 years). Patients with physician‐diagnosed FA in Japan (prevalent cohort) were divided into high‐risk or low‐risk cohorts using adrenaline prescription. The high‐risk cohort was further divided into anaphylaxis or nonanaphylaxis cohort based on the occurrence of anaphylaxis or a serious allergic reaction (SAR) during 1 year after adrenaline prescription. The primary objective was to examine yearly prevalence of FA. The secondary objectives were to describe demographics/clinical characteristics and healthcare resource utilization (HCRU), to evaluate the number of occurrences of anaphylaxis/SAR in the high‐risk cohort, and the impact of anaphylaxis/SAR on HCRU.ResultsThe overall standardized prevalence rate was 0.325% (95% confidence interval [CI], 0.311–0.339) in 2010 and 0.797% (95% CI, 0.790–0.804) in 2019 and predominant in patients age <6 years (preschool; 3.377% [95% CI, 3.229–3.525] in 2010 and 5.726% [95% CI, 5.663–5.789] in 2019). Majority of FA patients (>80%) were children/adolescent throughout the 10 years. While high‐risk cohort was a relatively minor population (8.5% in the prevalent cohort in 2019), the occurrence of anaphylaxis/SAR in the high‐risk cohort was 227,690/100,000 patient‐years. Multivariate analysis showed a significant increase in HCRU variables in the anaphylaxis versus nonanaphylaxis cohort (e.g., 2.08 [95% CI, 2.05–2.11] times more FA‐related outpatient visits).ConclusionsPrevalence of FA increased in a statistically significant way from 2010 to 2019; 1.7‐fold increase was observed in patients <6 years old. Patients in the high‐risk cohort appear to have suffered from frequent anaphylaxis/SAR, highlighting an unmet medical need for FA patients at “high‐risk,” considering the unavailability of approved medications to prevent anaphylaxis/SAR.