All-Cause and Cause-Specific Mortality Risks among Patients with Hidradenitis Suppurativa: A Korean Nationwide Population-Based Cohort Study

Although previous studies have reported increased mortality in patients with hidradenitis suppurativa (HS), the cause-specific mortality and the clinical characteristics attributable to greater mortality remain unclear. The aim of this study was to investigate all-cause and cause-specific mortality risks associated with HS. A retrospective population-based cohort study using the data linkage of the Nationwide Health Insurance Service database and the National Death Registry of Korea was conducted. Patients were defined as individuals with >3 documented visits with HS from 2003 to 2019. Controls were matched at a 1:10 ratio with age, sex, insurance type, and income level. The study included 26,304 patients with HS and 263,040 controls. Patients with HS showed a higher risk of all-cause mortality (hazard ratio = 1.152, 95% confidence interval = 1.051-1.263) than controls. However, the difference was comparable after further adjustment for body mass index, smoking, drinking, and comorbidity (adjusted hazard ratio = 1.038, 95% confidence interval = 0.946-1.138). For cause-specific mortality, the mortality from suicide/psychiatric disease (adjusted hazard ratio =1.449, 95% confidence interval = 1.098-2.911) and renal/urogenital disease (adjusted hazard ratio = 1.801, 95% confidence interval = 1.080-3.004) were independently higher among patients with HS even after adjustment for the confounding factors.