Food allergy and related risk factors in 2540 preschool children: an epidemiological survey in Guangdong Province, southern China

Background: Although the number of studies on allergic diseases in the general population of southern China is increasing, only a few have addressed food allergy (FA) in children in this region. The present study aimed to investigate the prevalence, clinical manifestations, spectrum of allergens, and related risk factors of FA in preschool children in Guangdong Province, southern China. Methods: A random cluster-sampling method was used to select 24 kindergartens from 12 cities in Guangdong Province. The parents or guardians of the children were requested to complete a questionnaire on general information and data regarding FA diagnosis and symptoms in the children and their first-degree relatives. Thereafter, the Chi-square test, multivariate regression analysis, and Spearman's rank-order correlation coefficient analysis were performed to identify statistically significant differences. Results: Analysis of 2540 valid questionnaires revealed an FA prevalence rate of 4%. Adverse food reactions were due to the consumption of shrimp (4.4%), crab (3.2%), mango (2.3%), cow's milk and dairy products (1.9%), and eggs (1.4%). Logistic regression analysis indicated that a history of FA and a history of allergic rhinitis in the first-degree relatives were the major factors leading to FA in children. Conclusions: The incidence of FA in children in Guangdong Province is higher than that commonly believed. An individual's genetic background is an important risk factor for FA. Hence, mitigation of the impact of lifestyle and environmental factors should be carefully considered to reduce the incidence of childhood FA.