Increased risk of stroke among patients with ulcerative colitis: A population-based matched cohort study

Background: The risk of venous thromboembolism (VTE) and the development of atherosclerosis are increased in patients with inflammatory bowel disease (IBD). Ulcerative colitis (UC) is one type of IBD; however, there is controversy in the literature regarding the association between UC and stroke. The present cohort study estimated the risk of subsequent stroke among UC patients compared with that among matched comparison subjects drawn from a population-based data set in Taiwan. Methods: This investigation analyzed administrative claims data sourced from the Taiwan National Health Insurance Database. Our study consisted of a study cohort comprising 516 UC patients and a comparison cohort of 2,579 subjects without IBD. Cox proportional hazards regressions were performed to estimate the risk of subsequent stroke during the follow-up period. We also conducted additional analyses investigating the risk of subsequent stroke by age group and gender. Results: After adjusting for selected medical co-morbidities and recent prescriptions of selected pharmaceuticals, the hazard ratio (HR) for subsequent stroke among patients with UC was 2.045 (95 % confidence interval (CI)=1.374-3.043) than that among comparison subjects. While we did not detect an association between stroke and UC among patients aged 30-40 or 40-50 years, we did detect increased risks for stroke among UC patients aged over 50 years (HR=2.045). We also found the association to remain significant for both men (HR=2.153) and women (HR=2.750). Conclusions: This study detected an increased HR for subsequent stroke among Taiwanese UC patients when compared to that among matched comparison patients without IBD.