Risk of Hidradenitis Suppurativa Comorbidities Over Time: A Prospective Cohort Study of Danish Blood Donors.

Hidradenitis suppurativa is a common recurrent inflammatory skin disease. It is associated with multiple comorbidities whose temporal relationships are unknown due to long diagnostic delays. This study of otherwise healthy blood donors with self-reported symptoms of hidradenitis suppurativa investigated the temporal relationships of comorbidities. A prospective survival analysis on a nationwide cohort of blood donors, using registry data on drug prescription, was used to calculate the hazard ratio of time until first prescription of medical treatment for the following hidradenitis suppurativa-related comorbidities: heart disease, diabetes, depression, thyroid disease and pain. Hidradenitis suppurativa status was determined by a validated questionnaire, and the survival analysis was adjusted for age, sex, body mass index, smoking status and having an International Classification of Diseases Version 10 (ICD-10) diagnosis of hidradenitis suppurativa. Of the participants, 1,012 reported hidradenitis suppurativa symptoms, and these symptoms increased the hazard ratio of antidepressants (1.73, 95% confidence interval 1.17-2.56, p ≈ 0.006) and analgesics (hazard ratio 1.24, 95% confidence interval 1.11-1.39, p < 0.001). Pain and depression are the first comorbidities to present in hidradenitis suppurativa pathogenesis.