Risk Factors for Venous Thromboembolism in Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis by Phase of Care.

Background: Risk factors for venous thromboembolism (VTE) and their relative magnitudes across different phases of care in inflammatory bowel disease (IBD) are poorly understood. Therefore, we performed a systematic review to identify risk factors for VTE in patients with IBD during the hospitalized, post-operative, post-discharge, and ambulatory phases of care.

Methods: MEDLINE, EMBASE, and Cochrane CENTRAL were systematically searched from inception through to April 2024 without language restriction. We included studies that reported risk factors for VTE among adults with IBD. Summary estimates with 95% confidence intervals (CIs) were calculated for individual risk factors overall and stratified by phase of care using random effects models.

Results: A total of 123 studies with over 23 510 969 patients were analyzed. We identified 48 variables for meta-analysis overall and 27 were significantly associated with VTE. The strongest risk factors were prior VTE (odds ratio [OR], 4.44; 95% CI, 2.63-7.49), surgical complications (OR, 3.06; 95% CI, 2.48-3.77), urgent surgery (OR, 2.33; 95% CI, 1.62-3.35), blood transfusions (OR, 2.68; 95% CI, 1.17-6.12), hypoalbuminemia (OR, 2.25; 95% CI, 1.93-2.62), and total parenteral nutrition (OR, 2.21; 95% CI, 1.85-2.64). Corticosteroids (OR, 1.60; 95% CI, 1.46-1.76) but not anti-tumor necrosis factor therapy (OR, 0.66; 95% CI, 0.46-0.97) were associated with an increased risk of VTE. No major differences were observed for most variables between hospitalized, post-operative, and post-discharge settings.

Conclusions: We identified multiple risk factors associated with VTE across different phases of care. This work will help in the development of future predictive models to guide thromboprophylaxis in IBD.