Incidence of anxiety disorder among adults with hidradenitis suppurativa.

BACKGROUND:There is limited data on risk of new-onset anxiety disorders in hidradenitis suppurativa (HS) patients. OBJECTIVES:To compare the risk of new-onset anxiety disorder in patients with HS and controls, and to describe risk factors for development of anxiety among HS patients. METHODS:Retrospective cohort analysis of a US electronic health records database between 2011-2020. Adults newly diagnosed with HS at a dermatology or primary care visit and controls were included. The primary outcome was new diagnosis of generalized anxiety disorder, phobic disorders, panic disorder, or unspecified anxiety. Cox proportional hazards regression was used to compare the crude risk of any anxiety disorder between groups and assess independent association with HS while controlling for potential demographic, clinical, and healthcare-related confounders. RESULTS:Among 9,597 HS patients and 959,493 controls, the incidence rate of anxiety was 5.74 and 3.86 per 100 person-years, respectively. Crude risk among all patients was 48% higher for those with HS compared to controls (HR 1.48, 95%CI 1.40-1.55). When stratifying by index encounter type, HS patients had 2.43 (95%CI 2.13-2.77) times the risk of anxiety disorder compared to dermatology controls and 1.46 (95%CI 1.38-1.55) times the risk compared to primary care controls. Adjusted hazard ratio for HS vs. control was 1.11 (95%CI 1.05-1.17) overall, 1.26 (95%CI 1.07-1.48) in the dermatology subgroup, and 1.07 (95%CI 1.01-1.13) in the primary care subgroup. Risk factors for incident anxiety diagnosis among HS patients included depression (HR 1.69, 95%CI 1.48-1.93), female sex (HR 1.41, 95% CI 1.23-1.60), younger age (HR 0.87 per 10-year increase, 95%CI 0.84-0.90), White race, Medicaid insurance (HR 1.22, 95%CI 1.07-1.40), tobacco smoking (HR 1.16, 95%CI 1.03-1.31), and having one or more emergency department visits in the year before HS diagnosis. Absolute incidence rates of anxiety disorders were highest among HS patients who were aged 18-29 years (7.10 per 100 person-years), female (6.34 per 100 person-years), and White (6.79 per 100 person-years). CONCLUSIONS:HS is independently associated with increased risk of anxiety disorders. An increased risk remains, but is attenuated, when controlling for confounders. The relative risk may be particularly high among patients managed by dermatologists.