Importance: The true prevalence of hidradenitis suppurativa (HS) is unknown.
Objective: To establish standardized overall and group-specific prevalence estimates for HS in the United States.
Design, setting, and participants: This retrospective analysis included a demographically heterogeneous population-based sample of more than 48 million unique patients across all US census regions. As of October 27, 2016, a total of 47 690 patients with HS were identified using electronic health record data.
Main outcomes and measures: Standardized overall point prevalence for HS and sex-, age-, and race-specific prevalence estimates of HS in the general US population.
Results: Of the 47 690 patients with HS (26.2% men and 73.8% women), the overall HS prevalence in the US population sample was 0.10%, or 98 per 100 000 persons (95% CI, 97-99 per 100 000 persons). The adjusted prevalence in women was 137 per 100 000 (95% CI, 136-139 per 100 000), more than twice that of men (58 per 100 000; 95% CI, 57-59 per 100 000; P < .001). The prevalence of HS was highest among patients aged 30 to 39 years (172 per 100 000; 95% CI, 169-275 per 100 000) compared with all other age groups (range, 15-150 per 100 000; P < .001). Adjusted HS prevalences among African American (296 per 100 000; 95% CI, 291-300 per 100 000) and biracial (218 per 100 000; 95% CI, 202-235 per 100 000) patients were more than 3-fold and 2-fold greater, respectively, than that among white patients (95 per 100 000; 95% CI, 94-96 per 100 000; P < .001).
Conclusions and relevance: Hidradenitis suppurativa is an uncommon, but not rare, disease in the United States that disproportionately affects female patients, young adults, and African American and biracial patients.