Effectiveness and safety of prophylactic anticoagulation among hospitalized patients with inflammatory bowel disease

Hospitalized patients with inflammatory bowel disease (IBD) are at increased risk of venous thromboembolism (VTE). We aimed to evaluate the effectiveness and safety of prophylactic anticoagulation compared with no anticoagulation in hospitalized patients with IBD. We conducted a retrospective cohort study using a hospital-based database. We included patients with IBD who had a length of hospital stay ≥2 days between 1 January 2016 and 31 December 2019. We excluded patients who had other indications for anticoagulation, users of direct oral anticoagulants, warfarin, therapeutic-intensity heparin, and patients admitted for surgery. We defined exposure to prophylactic anticoagulation using charge codes. The primary effectiveness outcome was VTE. The primary safety outcome was bleeding. We used propensity score matching to reduce potential differences between users and nonusers of anticoagulants and Cox proportional-hazards regression to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). The analysis included 56 194 matched patients with IBD (users of anticoagulants, n = 28 097; nonusers, n = 28 097). In the matched sample, prophylactic use of anticoagulants (vs no use) was associated with a lower rate of VTE (HR, 0.62; 95% CI, 0.41-0.94) and with no difference in the rate of bleeding (HR, 1.05; 95% CI, 0.87-1.26). In this study of hospitalized patients with IBD, prophylactic use of heparin was associated with a lower rate of VTE without increasing bleeding risk compared with no anticoagulation. Our results suggest potential benefits of prophylactic anticoagulation to reduce the burden of VTE in hospitalized patients with IBD.