Rosacea in Patients with Ulcerative Colitis and Crohn's Disease: A Population-based Case-control Study.

Background: Cutaneous manifestations are common in patients with inflammatory bowel diseases (IBDs) (ulcerative colitis [UC] and Crohn's disease [CD]). Previous case reports described patients with IBD who developed rosacea. IBD and rosacea are inflammatory epithelial diseases, presumably associated with changes in the innate immune system. We explored the association between IBD and incident rosacea.
Methods: We conducted a population-based matched (1:1) case-control analysis on the association between IBD and rosacea, stratified by IBD disease duration and severity. We used data from the UK-based Clinical Practice Research Datalink. Cases had an incident diagnosis of rosacea recorded between 1995 and 2013.
Results: Among 80,957 rosacea cases and the same number of controls, a history of UC was associated with an increased risk of rosacea (odds ratio [OR] 1.65, 95% confidence interval [CI], 1.43-1.90), with the highest OR in those with short UC duration (OR 2.85, 95% confidence interval, 1.80-4.50 for patients with <2 years of disease history). A history of CD yielded an overall OR of 1.49 (95% CI, 1.25-1.77), which did not correlate with disease duration. Additional analyses on IBD disease severity yielded evidence for a higher risk of rosacea in those with higher UC and CD activity.
Conclusions: Our findings provide evidence that patients with IBD may be at increased risk of rosacea (higher in UC), particularly during phases of increased IBD-associated gastrointestinal tract inflammation.