Overall and subgroup prevalence of acne vulgaris among patients with hidradenitis suppurativa.

Background: Evidence establishing a link between acne vulgaris (AV) and hidradenitis suppurativa (HS) is limited, and the burden of AV in adults with HS is unknown.
Objective: To determine the prevalence of AV among adults with HS and determine the strength of this association.
Methods: Cross-sectional analysis identifying adults with AV among patients with and without HS by using electronic health record data from a population-based sample of more than 55 million patients.
Results: The prevalence of AV among adults with HS was 15.2% (7315 of 48,085) compared with 2.9% (497,360 of 16,899,470) for adults without HS (P < .001). The prevalence was greatest among patients with HS who were female (5870 of 35,790 [16.4%]), were 18 to 44 years old (5260 of 28,870 [18.2%]), were nonwhite (3120 of 17,825 [17.5%]), were obese (5430 of 35,135 [15.5%]), and had polycystic ovarian syndrome (685 of 2385 [28.7%]). Patients with HS had 4.51 [95% confidence interval, 4.40-4.63] times the odds of having AV than did patients without HS, with the higher likelihood of having AV persisting across all subgroups of patients with HS. The association between HS and AV was generally stronger for patients who were male, and 65 years of age or older.
Limitations: Influence of disease severity in HS, or in acne, on the strength of the association could not be assessed.
Conclusion: Patients with HS may benefit from assessment of acne status and optimization of comanagement strategies.
(Copyright © 2018 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.)