Hidradenitis suppurativa and metabolic syndrome - systematic review and adjusted meta-analysis

Background Hidradenitis suppurativa (HS) is a debilitating and distressing chronic systemic inflammatory skin disease. There have been several prior observational studies which reported a possibility link between HS and metabolic syndrome, however the current evidence is not definitive. It is unclear in HS whether this possible relationship is independent or driven by underlying risk factors and comorbidities. Objective To determine whether HS is independently associated with metabolic syndrome via adjusted meta-analysis of case-control studies. Methods A systematic review and meta-analysis was performed according to PRISMA guidelines. Electronic searches were performed using six electronic databases (Ovid Medline, PubMed, CCTR, CDSR, ACP Journal Club, and DARE) from their inception until September 2018. Data were extracted and analyzed according to predefined clinical endpoints. Results We identified six case-control studies included for meta-analysis. Based on unadjusted analysis, we found a significant association between adult cases of HS and metabolic syndrome (OR 1.95, 95% CI 1.31-2.89, P = 0.001). Adjusted meta-analysis, after adjustment for age, sex, other cardiovascular risk factors, and comorbidities, found a significant association (OR 2.19, 95% CI 1.70-2.81, I-2 = 32%, P < 0.00001). Limitations Studies reviewed were observational by design which are susceptible to bias, and there was lack of randomization. The quality of the current systematic review is also limited by the quality of available evidence which was predominantly observational in nature. Conclusions This pooled analysis of existing case-control studies supports an association between HS and metabolic syndrome. Clinicians treating patients with HS should be aware of this potential association.