Risk of inflammatory bowel disease in patients with rosacea: Results from a nationwide cohort study in Taiwan

Background A link between rosacea and inflammatory bowel disease (IBD) has been proposed with unknown mechanisms. Epidemiologic evidence of this association needs to be examined. Methods In this nationwide cohort study, a total of 89,356 patients with rosacea and 178,712 matched patients without rosacea between 1997 and 2013 were identified in the Taiwanese National Health Insurance Research Database. Cumulative incidences of IBD were compared between these 2 cohorts. Frailty Cox proportional hazard model was used and subgroup analyses were conducted to examine the risk factors for IBD. Results The 15-year cumulative incidences of IBD were 0.036% (95% confidence interval [CI] 0.00%-1.57%) and 0.019% (95% CI 0.00%-0.83%) in rosacea and nonrosacea cohorts, respectively (P = .05). Rosacea (adjusted hazard ratio 1.94, 95% CI 1.04-3.63, P = .04) and male gender (adjusted hazard ratio 3.52, 95% CI 2.03-6.11, P < .01) were independently associated with IBD, after adjustment for major comorbidities. Multivariate subgroup analyses revealed consistent results. The incidence rates of IBD decreased with increasing antibiotic use in patients with rosacea, but without statistical significance. Limitation Information related to lifestyle, diet, alcohol, and smoking was not included in the database. Conclusion Patients with rosacea may have an increased risk of IBD.