Association of atopic dermatitis with obesity via a multi-omics approach: A protocol for a case-control study.

Introduction: Several studies have found that obesity is associated with atopic dermatitis (AD); however, the mechanisms underlying the association are largely unknown. This study aims to assess the association of AD with obesity in the Korean population and verify its mechanism via a multi-omics analysis. Methods and analysis: A case-control study will be conducted in the Republic of Korea. A total of 80 subjects, aged 4 to 12 years, matched for age and sex, with body mass index at or above the 85th percentile or at or below the 25th percentile, will be included. Subjects will be assigned to the following 4 groups: obese/overweight with AD, normal/underweight with AD, obese/overweight control, and normal/underweight control. Serum metabolome and immune biomarkers, as well as fecal metabolome and microbiome biomarkers, will be analyzed. Serum eosinophil cationic protein, total serum Immunoglobulin E (IgE), and specific IgE will be analyzed to assess allergic tendency. The SCORing of AD index, the children's dermatology life quality index, body composition analysis, and the Korean gastrointestinal symptom rating scale will be obtained to assess the disease status and severity of the subjects. Discussion: The findings of this study are expected to provide evidence of an association between AD and obesity via a gut microbiome-metabolome-immune mechanism. Therefore, it may improve future management strategies for AD.