Associations of Comorbid Atopic Dermatitis, Food Allergy, and Respiratory Allergic Diseases with Somatic Problems in Children: A Birth Cohort Study

Background/Objectives: Atopic dermatitis (AD) and food allergy (FA) frequently coexist in the concept of atopic march; however, their combined associations with psychological problems remain poorly understood. This study aimed to investigate the associations of AD and FA with psychological outcomes at age 7 and evaluate whether respiratory allergies account for part of these associations. Methods: We enrolled 1577 children aged 7 years from the Panel Study of Korean Children. The Korean version of the Child Behavior Checklist was used to assess psychological and behavioral problems. Multivariable regression and parallel mediation analyses were used to evaluate independent and interactive associations. Results: AD and FA were associated with psychological and behavioral problems, most consistently with somatic problems on the Diagnostic and Statistical Manual of Mental Disorders (DSM)-oriented scale. These associations were more pronounced in children with comorbid AD and FA than in those with single allergies. Among the 9 children with concurrent AD and FA, an interaction between the two conditions on somatic problems was observed (P for interaction = 0.033). The comorbid group showed higher eosinophil counts and total IgE levels, but no differences in SCORAD indices or C-reactive protein levels. Mediation analysis identified a direct association of AD with somatic problems (B = 1.062; 95% CI, 0.601–1.562), with a portion accounted for by allergic rhinitis (AR) (B = 0.656; 95% CI, 0.306–1.241). Conclusions: Comorbid AD and FA were associated with higher odds of somatic problems than either condition alone in 7-year-old children, with a portion of the AD association accounted for by AR. Because exposures and outcomes were assessed concurrently, these associations are exploratory and hypothesis-generating rather than causal. Clinical attention may be warranted for children with both AD and FA.