Autoimmune, Autoinflammatory Disease and Cutaneous Malignancy Associations with Hidradenitis Suppurativa: A Cross-Sectional Study

Background: Hidradenitis suppurativa (HS) is a debilitating cutaneous disease characterized by severe painful inflammatory nodules/abscesses. At present, data regarding the epidemiology and pathophysiology of this disease are limited. Objective: To define the prevalence and comorbidity associations of HS. Methods: This was a cross-sectional study of EPIC^TM Cosmos^© examining over 180 million US patients. Prevalences were calculated by demographic and odds ratios (OR) and identified comorbidity correlations. Results: All examined metabolism-related, psychological, and autoimmune/autoinflammatory (AI) diseases correlated with HS. The strongest associations were with pyoderma gangrenosum [OR 26.56; confidence interval (CI): 24.98–28.23], Down syndrome (OR 11.31; CI 10.93–11.70), and polycystic ovarian syndrome (OR 11.24; CI 11.09–11.38). Novel AI associations were found between HS and lupus (OR 6.60; CI 6.26–6.94) and multiple sclerosis (MS; OR 2.38; CI 2.29–2.48). Cutaneous malignancies were largely not associated in the unsegmented cohort; however, among Black patients, novel associations with melanoma (OR 2.39; CI 1.86–3.08) and basal cell carcinoma (OR 2.69; CI 2.15–3.36) were identified. Limitations: International Classification of Diseases (ICD)-based disease identification relies on coding fidelity and diagnostic accuracy. Conclusion: This is the first study to identify correlations between HS with melanoma and basal cell carcinoma (BCC) among Black patients as well as MS and lupus in all patients with HS.