Key clinical point: Patients with microscopic colitis (MC) were at nearly 2-fold higher risk of developing rheumatoid arthritis (RA) compared with the general population, with a significant risk persisting up to 5 years after MC diagnosis.
Major finding: The risk for RA was significantly higher in patients with MC compared with matched reference individuals (adjusted hazard ratio [aHR] 1.83; 95% CI 1.39-2.41) and full siblings without MC (aHR 2.04; 95% CI 1.18-3.56). The risk was highest during the first year of follow-up (aHR 2.31; 95% CI 1.08-4.97) and remained significantly high up to 5 years after MC diagnosis (aHR 2.16; 95% CI 1.42-3.30).
Study details: Findings are from a population-based matched cohort study including 8179 patients with biopsy-verified MC, 36,400 matched reference individuals, and 8202 full siblings without MC.
Disclosures: This study was funded by Karolinska Institutet and other sources. Some authors declared serving as study coordinators or advisory board members for, receiving financial support from, and reporting agreements between various sources.
Source: Bergman D et al. Microscopic colitis and risk of incident rheumatoid arthritis: A nationwide population-based matched cohort study. Aliment Pharmacol Ther. 2023 (Sep 20). D+oi: 10.1111/apt.17708