Parent-reported adverse food reactions in Hong Kong Chinese pre-schoolers: epidemiology, clinical spectrum and risk factors

The epidemiology of adverse food reactions (AFRs), including the potentially life-threatening food allergy (FA), in Asia is unclear. AFR is believed to be less prevalent than in Caucasians. This study determines the prevalence, clinical features and risk factors for parent-reported AFR in Chinese pre-school children in Hong Kong. Children aged 2–7 yr living in Hong Kong were recruited through local nurseries and kindergartens to ascertain the occurrence and clinical spectrum of AFR and other atopic disorders. Subjects' parents answered a self-administered questionnaire that was modified and validated based on the International Study of Asthma and Allergy in Childhood. A total of 3827 children from 21 nurseries and kindergartens returned the study questionnaires, and information on AFR was analyzable for 3677 (96.1%) children. The prevalence rates of parent-reported AFR and parent-reported, doctor-diagnosed AFR were 8.1% and 4.6%, respectively, whereas 5.0% of pre-schoolers had doctor-diagnosed asthma. The six leading causes of AFR were shellfish (15.8%), egg (9.1%), peanut (8.1%), beef (6.4%), cow's milk (5.7%), and tree nuts (5.0%). When compared with children born and raised in Hong Kong, children born in mainland China (n = 253) had less parent-reported AFR (4.0% vs. 6.7%; p = 0.016). On logistic regression, parent-reported AFR was associated with younger age (p = 0.010), born in mainland China (p = 0.038), and AFR history in father (p = 0.001), mother (p < 0.001), siblings (p = 0.020), and paternal history of rhinitis (p = 0.044). This study shows that AFR is a common atopic disorder in Hong Kong pre-school children, and prevalence rates are comparable to the Caucasians.