Early-Life Risk Factors and Clinical Features of Food Allergy Among Thai Children.

Background: Food allergy affects 1%-10% of children under five worldwide, with genetic and early-life factors playing a primary role. Reported factors include a family history of allergic diseases, personal atopic dermatitis, cesarean section, dietary restrictions during pregnancy and lactation, and the timing of introducing solid foods. This study was aimed at identifying various factors associated with food allergy and evaluate each food allergy's clinical features. Methods: We conducted a case-control study with a participant ratio of 1:2 between cases and controls. Data were gathered from both groups of participants, and questionnaires included living area, sex, and natal history (birth details, maternal diet during pregnancy and breastfeeding, feeding history during infancy, family history of atopic diseases, and household smoking). Results: All 72 cases with food allergy and 145 controls were included in the study. Term birth comprised a protective factor for developing food allergy (adjusted odds ratio [aOR] 0.213, p value 0.022). In contrast, personal atopic dermatitis (aOR 20.097, p value 0.001) and a family history of allergic disease constituted risks (aOR 3.183, p value 0.002). Food allergy was unrelated to cesarean section, low birth weight, dietary restrictions during lactation and pregnancy, exclusive breastfeeding, or the early introduction of complementary foods. The three most common food allergens were egg white (40.2%), wheat (34.7%), and cow's milk (30.5%), respectively. Conclusions: In this study, risk factors associated with food allergy comprised a personal history of atopic dermatitis and a family allergic disease, which may be used as predictive factors for developing food allergy among Thai children.