A retrospective, population-based cohort study observed a bidirectional association between hidradenitis suppurativa (HS) and atopic dermatitis (AD). The results of the study were published in the Journal of the American Academy of Dermatology.
To explore a potential association, the authors sought to compare the incidence rate of AD among patients with HS with age-, gender-, and ethnicity-matched controls. In total, the study included 6776 patients with HS and 33,260 controls. Analysis was based on adjusted hazard ratio (HRs) and adjusted odds ratios (ORs).
Among the patients with HS, the incidence of AD was 2.51 (95% CI, 2.07-3.02) per 1000 person-years. Comparatively, the incidence of AD among the control group was 1.24 (95% CI, 1.10-1.40) per 1000 person-years. Based on these data, the authors found patients with HS were twice as likely to develop AD than controls (HR, 2.06; 95% CI, 1.64-2.58).
Additionally, more patients with HS also had preexisting AD than controls (2.5% vs 1.8%, respectively). A prior history of AD was associated with 40% increased odds of also having HS (OR, 1.41; 95% CI, 1.19-1.67).
Patients with both HS and AD were younger and had a female predominance, a lower prevalence of smoking, and a lower body mass index vs patients with HS alone.
In conclusion, the authors stated, a bidirectional association between the two diseases was observed. They added that dermatologists should be aware of this association.
Sherman S, Kridin K, Bitan DT, Leshem YA, Hodak E, Cohen AD. Hidradenitis suppurativa and atopic dermatitis: a two-way association. J Am Acad Dermatol. Published online December 27, 2020. doi:10.1016/j.jaad.2020.12.051