Characteristics and Risk Factors of Pollen-Food Allergy Syndrome in Patients With Hay Fever: A Digital Cross-Sectional Cohort Study Using AllerSearch.

Abstract

Background and objectives: Pollen-food allergy syndrome (PFAS) is a frequent comorbidity in individuals with hay fever. Identifying risk factors and allergen clusters can aid targeted interventions and management strategies. Objective: This study characterizes PFAS in patients with hay fever and identifies associated risk factors using the mobile health platform, AllerSearch.

Methods: A digital cross-sectional cohort study was conducted in Japan from August 2020 to September 2024. Participants provided demographic, medical, lifestyle, and environmental data via AllerSearch. PFAS was identified based on self-reported allergic reactions to specific fruits and vegetables. Allergen patterns were analyzed using Uniform Manifold Approximation and Projection clustering, and risk factors were assessed via multivariable logistic regression.

Results: Among 2874 participants, 2352 had hay fever, and 1788 (23.9%) reported PFAS. The most common triggers were melon (22.9%), kiwi (18.3%), and tomato (11.7%). Significant risk factors included a history of allergic disease (OR, 1.58), asthma (1.44), atopic dermatitis (1.90), urticaria (2.73), contact lens discontinuation during hay fever season (1.50), sensitivity to yellow sand or particulate matter 2.5 (3.42), and drug allergy (3.04). Seven allergen clusters were identified, with Cluster 6 exhibiting broad allergen sensitivity and the remaining clusters each associated with a single food. Onset of hay fever was earlier in Clusters 1, 4, and 6 than in non-PFAS individuals (P=.002, P=.002, and P=.002, respectively).

Conclusions: This study highlights key factors and allergen clusters associated with PFAS using a mobile health approach. Our findings may facilitate tailored interventions and improve quality of life for affected individuals.