The Incidence of Arterial Thromboembolic Diseases in Inflammatory Bowel Disease: A Population-Based Study

Background & Aims: We aimed to determine if there was an increased risk for arterial thromboembolic diseases (ATED) in inflammatory bowel disease (IBD). Methods: We used the University of Manitoba IBD Epidemiology Database (1984–2003) (n = 8060), and a matched cohort (n = 80,489) drawn from the Manitoba Health administrative database. Each IBD case and non-IBD control has a unique personal health identification number and each health system encounter is identified by a diagnostic code (International Classification of Diseases, 9th revision [ICD-9]). We compared the IBD with the non-IBD cohorts for the incidence of ATED events following the index case diagnosis of IBD including: ischemic heart disease (ICD-9-Clinical Modification [CM] codes 410–414.x), cerebrovascular disease (ICD-9-CM codes 430–436.x), and undifferentiated ATED (ICD-9-CM codes 440.x and 445.x). The incidence rate of 1 episode or more of these diseases was assessed in relation to the individual person-years of follow-up evaluation. Incidence rates and incidence rate ratios (IRRs) were computed for all IBD, and stratified by IBD diagnosis, sex, and age. Results: For ischemic heart disease, risk was increased for all IBD (IRR, 1.26; 95% confidence interval [CI], 1.11–1.44) and was increased for Crohn’s disease and ulcerative colitis in both, males and females. For cerebrovascular disease, only Crohn’s disease was associated with increased risk (IRR, 1.32; 95% CI, 1.05–1.66), and for undifferentiated ATED only females (IRR, 1.96; 95% CI, 1.24–3.10) and those aged 0 to 39 years (IRR, 19.95; 95% CI, 1.81–219.92) and 40 to 59 years (IRR, 3.17; 95% CI, 1.27–7.91) had significantly increased risks. Conclusions: IBD patients are more likely to have cardiac ATED, regardless of diagnosis or sex. Crohn’s disease has an increased risk for cerebral ATED. Smoking, the prothrombotic aspect of systemic inflammation, or a genetic predisposition may contribute to the risk.