Prevalence of hidradenitis suppurativa: a population-based study in Olmsted County, Minnesota.

Background: Hidradenitis suppurativa (HS) is a follicular occlusion disorder occurring in apocrine-rich regions of the skin. Estimates of the prevalence of this disorder have not been population-based. Objective: We sought to provide population-based information on the prevalence of HS in Olmsted County, Minnesota, as of January 1, 2009. Methods: The Rochester Epidemiology Project, a unique infrastructure that combines and makes accessible all medical records in Olmsted County since the 1960s, was used to collect population-based data on the prevalence of HS. Results: We identified 178 confirmed cases of HS that included 135 females and 43 males, and estimated the total sex- and age-adjusted prevalence in Olmsted County to be 127.8 per 100,000 or 0.13%. The total prevalence was significantly higher among women than men. Conclusion: This study represents the first population-based investigation on the prevalence of HS. In this population-based cohort, HS was less prevalent than suggested by previous reports.