Venous thromboembolism in inflammatory bowel disease

Patients with inflammatory bowel disease (IBD) are at an increased risk for venous thromboembolism (VTE). VTE events carry significant morbidity and mortality, and have been associated with worse outcomes in patients with IBD. Studies have suggested that the hypercoagulable nature of the disease stems from a complex interplay of systems that include the coagulation cascade, natural coagulation inhibitors, fibrinolytic system, endothelium, immune system, and platelets. Additionally, clinical factors that increase the likelihood of a VTE event among IBD patients include older age (though some studies suggest younger patients have a higher relative risk of VTE, the incidence in this population is much lower as compared to the older IBD patient population), pregnancy, active disease, more extensive disease, hospitalization, the use of certain medications such as corticosteroids or tofacitinb, and IBD-related surgeries. Despite the increased risk of VTE among IBD patients and the safety of pharmacologic prophylaxis, adherence rates among hospitalized IBD patients appear to be low. Furthermore, recent data suggests that there is a population of high risk IBD patients who may benefit from post-discharge prophylaxis. This review will provide an overview of patient specific factors that affect VTE risk, elucidate reasons for lack of VTE prophylaxis among hospitalized IBD patients, and focus on recent data describing those at highest risk for recurrent VTE post-hospital discharge.