There is a strong association between hidradenitis suppurativa (HS) and schizophrenia, especially in patients between the ages of 30 and 69 years and smokers, according to study results published in the Journal of the European Academy of Dermatology and Venereology.
Investigators used data provided by Clalit Health Services, the largest managed healthcare company in Israel. Patients diagnosed with HS (n=4191) and age- and sex-matched control patients (n=20,941) were included in the study. Multivariate binary logistic regression was used to assess the association between HS and schizophrenia, adjusting for smoking status and demographic factors.
Analysis revealed a tenfold increase in the prevalence of schizophrenia in patients with HS compared with patients in the control group (1.4% and 0.4% respectively, odds ratio [OR] 3.5, 95% CI 2.49-4.92, P <.001). There was more than a threefold increase in prevalence observed in the 30 to 49 age group (1.8% and 0.5%, respectively; OR, 3.83; 95% CI, 2.44-5.99), and a fourfold increase was demonstrated in the 50 to 69 age group (2% and 0.5%, respectively; OR, 3.74; 95% CI, 1.99-7.03). Schizophrenia in patients with HS was also associated with lower socioeconomic status and smoking. In multivariate analysis, HS was found to be independently and positively associated with schizophrenia (OR, 1.44; 95% CI, 1.01-2.07; P <.05). Schizophrenia was also positively associated with smoking (OR, 2.5; 95% CI 1.75-3.78, P <.001), socioeconomic status (OR, 1.66; 95% CI, 1.17-2.37; P <.01), and age (OR, 1.01; 95% CI, 1-1.03; P <.01).
Investigators hypothesized that comorbid schizophrenia and HS could be caused by immune system dysfunction, possibly related to cytokine abnormalities, or by environmental factors, as suggested by smoking behavior. Future studies might consider the impact of adherence to psychotropic and dermatologic treatments on the relationship between schizophrenia and HS, as well the role of schizophrenic symptom severity.
“[The] results of the current study emphasize the importance of integrating a broader assessment to detect and account for both dermatological and psychological factors that might affect medical care,” investigators wrote. “This assessment is especially crucial when considering the higher prevalence of attempted suicide in both schizophrenia and HS patients, as well as the importance of early treatment in both HS and schizophrenia, which might dramatically affect treatment options and outcomes.”
Disclosure: One of the study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Tzur Bitan D, Berzin D, Cohen AD. Hidradenitis suppurativa (HS) and schizophrenia: a nationwide cohort study [published online October 6, 2019]. J Eur Acad Dermatol Venereol. doi:10.1111/jdv.15997