Factor associated with food allergy among preschool children with atopic dermatitis, and resolution of atopic dermatitis.

Background: Food allergy (FA) has been reported in one-third of children with moderate-to-severe atopic dermatitis (AD).
Objective: To identify factor associated with food allergy among preschool children with AD, and to compare AD resolution between preschool children with and without FA.
Methods: A cross-sectional study using database registry and questionnaire interview was conducted at Siriraj Hospital(Bangkok, Thailand) during 2022, and physician-diagnosed AD children aged ≤ 6 years were enrolled.
Results: A total of 110 children (60.9% male, median age: 2.3 years) were included. Of those, 53 and 57 children had AD with and without FA, respectively. Very early-onset AD (≤ 3 months) and moderate-to-severe AD at onset were reported in 43.9% and 26.3% of AD without FA, and in 35.8% and 45.3% of AD with FA, respectively. The most commonly reported FAs were hen's egg, cow's milk, and wheat. Moderate-to-severe AD at onset was found significant associated with FA (aOR: 2.50; p = 0.037). Thirty-one (28.2%) patients experienced completed resolution of AD by 5 years of age. Of those, 19 had AD without FA, and 12 had AD with FA (p = 0.213). The median age at AD resolution was 18 months and 22.5 months in the without and with FA groups, respectively. AD with FA showed a strong trend toward a significantly longer duration to achieving AD resolution after adjusting for onset and severity of AD (aHR: 0.46, p = 0.050).
Conclusion: Preschool AD children with FA were found to have significantly greater AD severity at AD onset and a longer duration to AD resolution compared to AD children without FA.