Inflammatory Bowel Disease and Risk of Major Bleeding During Anticoagulation for Venous Thromboembolism.

BACKGROUND Little is known about the bleeding risk in patients with inflammatory bowel disease (IBD) and venous thromboembolism (VTE) treated with anticoagulation. Our aim was to elucidate the rate of major bleeding (MB) events in a well-defined cohort of patients with IBD during anticoagulation after VTE. METHODS This study is a retrospective follow-up analysis of a multicenter cohort study investigating the incidence and recurrence rate of VTE in IBD. Data on MB and IBD- and VTE-related parameters were collected via telephone interview and chart review. The objective of the study was to evaluate the impact of anticoagulation for VTE on the risk of MB by comparing time periods with anticoagulation vs those without anticoagulation. A random-effects Poisson regression model was used. RESULTS We included 107 patients (52 women, 40 with ulcerative colitis, 64 with Crohn disease, and 3 with unclassified IBD) in the study. The overall observation time was 388 patient-years with and 1445 patient-years without anticoagulation. In total, 23 MB events were registered in 21 patients, among whom 13 MB events occurred without anticoagulation and 10 occurred with anticoagulation. No fatal bleeding during anticoagulation was registered. The incidence rate for MB events was 2.6/100 patient-years during periods exposed to anticoagulation and 0.9/100 patient-years during the unexposed time. Exposure to anticoagulation (adjusted incidence rate ratio, 3.7; 95% confidence interval, 1.5-9.0; P = 0.003) and ulcerative colitis (adjusted incidence rate ratio, 3.5; 95% confidence interval, 1.5-8.1; P = 0.003) were independent risk factors for MB events. CONCLUSION The risk of major but not fatal bleeding is increased in patients with IBD during anticoagulation. Our findings indicate that this risk may be outweighed by the high VTE recurrence rate in patients with IBD.