Atopic dermatitis and the metabolic syndrome: a cross-sectional study of 116 816 patients

Background: Data regarding the association between atopic dermatitis (AD) and the metabolic syndrome are controversial. Objective: To evaluate the prevalence of the metabolic syndrome and its components in a large group of patients with AD compared to a matched reference group. Methods: A cross-sectional study of AD patients diagnosed by a dermatologist between 1998 and 2016, and a matched comparison group was performed. We analysed the association between AD and metabolic syndrome, its components and possible complications for the entire study population, adults (age > 18) and adults with moderate-to-severe AD. Results: The study included 116 816 patients with AD and 116 812 comparison enrollees. AD in the entire group of patients and in the adult patients was associated with a higher prevalence of dyslipidaemia and a lower prevalence of diabetes and metabolic syndrome. Moderate and severe AD were associated, respectively, with higher prevalence rates of the metabolic syndrome (17.0% vs. 9.4%), its components (obesity: 22.2% vs. 18.6%; diabetes: 15.9% vs. 9.2%; hypertension 27.9% vs. 15.3%; dyslipidaemia 47.1% vs. 28.5%, all P values < 0.001) and cardiovascular morbidity (all P values < 0.001). Multivariate analysis demonstrated a significant overrepresentation of the metabolic syndrome in moderate-to-severe AD (P = 0.04). Conclusions: Severely affected patients with AD may have one or more undiagnosed components of metabolic syndrome.