Abstract
Despite some common pathogenic themes, the association of hidradenitis suppurativa (HS) and rheumatoid arthritis (RA) has been poorly investigated. We aimed to evaluate the bidirectional association between HS and RA. A population-based study was conducted to compare HS patients (n = 6779) with age-, sex- and ethnicity-matched control subjects (n = 33,260) with regard to the incidence of new-onset and the prevalence of preexisting RA. Adjusted hazard ratios (HRs) and adjusted odds ratios (ORs) were estimated. The prevalence of preexisting RA was greater among patients with HS relative to controls (0.5% vs 0.3%. respectively; p = 0.019). The odds of being diagnosed with HS were 1.6-fold higher in patients with a history of RA (fully-adjusted OR, 1.66; 95% CI, 1.11–2.49; p = 0.014). The incidence rate of new-onset RA was estimated at 4.3 (95% CI, 2.5–6.8) and 2.4 (95% CI, 1.8–3.2) cases per 10,000 person-years among patients with HS and controls, respectively. The risk of RA was comparable between patients with HS and controls (fully-adjusted HR, 1.45; 95% CI, 0.77–2.72; p = 0.249). Compared to other patients with HS, those with HS and comorbid RA were older, had a higher prevalence of diabetes mellitus, hypertension, and hyperlipidemia, and had a comparable risk of all-cause mortality. In conclusions, a preexisting diagnosis of RA predisposes individuals to develop HS. Clinicians managing patients with HS and RA should be aware of this association. Further research is required to delineate the underlying pathomechanism of this observation.
Highlights
Hidradenitis suppurativa (HS), previously termed ‘acne inversa’, is a chronic recurrent inflammatory cutaneous disease involving the pilosebaceous unit [1]
In an age, sex, and, ethnicity-stratified analysis, the association of Rheumatoid arthritis (RA) with subsequent HS was greater among individuals older than 40 years (OR, 1.73; 95% confidence intervals (CIs), 1.08–2.79; p = 0.022), males (OR, 2.22; 95% CI, 1.01–4.89; p = 0.041), and Arabs (OR, 2.93; 95% CI, 1.15–7.45; p = 0.018; Table 2)
The association between a history of RA and a later diagnosis of HS was only significant in individuals in whom the diagnosis of RA preceded that of HS by more than 10 years (OR, 1.99; 95% CI, 1.09–3.63; p = 0.022; Table 2)
Summary
Hidradenitis suppurativa (HS), previously termed ‘acne inversa’, is a chronic recurrent inflammatory cutaneous disease involving the pilosebaceous unit [1]. HS is characterized clinically by deep-seated nodules, abscesses, and draining sinus tracts that eventually end up as scaring tissue. These are located mostly in the groin, genital areas, and axillae, the inframammary area, neck, and other anatomical regions may be affected [2]. Rheumatoid arthritis (RA) is a chronic debilitating disease that manifests as persistent synovitis, which might lead to the destruction of joints and deformation of bones. It affects 0.5–1.0% of western populations, with the prototypical patient being a middle-aged woman.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
