Obsessive-compulsive disorder and the associated risk of autoimmune skin diseases: a nationwide population-based cohort study.

ABSTRACT

BACKGROUND: The concurrent incidence of autoimmune comorbidities in obsessive-compulsive disorder (OCD) is known. However, the association between OCD and related autoimmune skin diseases (ASDs) has not been well studied. OBJECTIVE: This study aimed to investigate the association between OCD and the risk of ASDs. METHODS: To assess the risk of developing ASDs, we recruited 44 324 patients with OCD and 177 296 matched controls from the National Health Insurance Research Database in Taiwan. A Cox regression model was used for the analyses. RESULTS: After adjusting for confounders, an increased risk of ASDs among the patients with OCD (adjusted hazard ratio [aHR] 6.36; 95% confidence interval [CI] 5.43-7.45) was found when compared to the controls. Statistically significant associations were found between OCD and seven individual ASDs, including psoriasis (aHR 12.52; 95% CI 8.78-17.85), lichen planus (aHR 27.22; 95% CI 13.09-56.60), alopecia areata (aHR 13.69; 95% CI 9.38-19.98), autoimmune bullous diseases (aHR 4.30; 95% CI 2.03-9.11), hidradenitis suppurativa (aHR 29.95; 95% CI 3.35-267.62), vitiligo (aHR 9.35; 95% CI 5.35-16.32), and lupus erythematosus (aHR 2.10; 95% CI 1.52-2.91). CONCLUSIONS: Patients with OCD had an increased risk of developing ASDs compared to matched controls. Further studies are required to clarify the underlying mechanisms.