Chronic pain is one of the most prominent symptoms of hidradenitis suppurativa (HS) and an independent domain in the core outcome set for HS. Previously, the chronic, recurrent, inflammatory nature of HS was hypothesized to induce central sensitization (CS; alteration and amplification of pain perception). However, evidence for this hypothesis is currently lacking.
To determine the prevalence of CS in patients with HS compared with sex- and age-matched controls.
This was a cross-sectional, survey-based, case-control study conducted from February to November 2020 that included all consecutive adult patients with HS attending the outpatient clinic of the Department of Dermatology of the Erasmus University Medical Center Rotterdam, in Rotterdam, the Netherlands. Age- and sex-matched controls without chronic inflammatory dermatologic diseases were recruited from the same department.
The main outcome was the Central Sensitization Inventory (CSI) score (ranging from 0-100) as a screening tool for presence of CS. Based on current literature, a score of 40 or higher was deemed to indicate the presence of CS.
Overall, 100 patients with HS (median [SD] age, 34.5 [27.3-47.0] years; 71 [71%] female) and 100 controls (median [SD] age, 33.5 [27.0-48.8] years; 71 [71%] female) were included, of which 36% and 12%, respectively, had a CSI score of 40 or higher (P < .001). Multivariate logistic regression showed that patients with HS had 4.46 (95% CI, 1.89-10.52; P = .001) times the odds of having a positive CSI compared with controls. In addition, CS was significantly associated with previously diagnosed depression (odds ratio, 6.16; 95% CI, 2.81-13.54; P < .001). No association between CSI score and disease severity was found.
In this cross-sectional, case-control study, patients with HS had more than 4 times the odds of having CS, indicated by a positive CSI, compared with age- and sex-matched controls. This new insight in the presence of CS in patients with HS raises the question of whether we are adequately measuring and treating HS-associated pain. Active screening for CS and depressive symptoms in patients with a discrepant pain experience is recommended.