Severity of Gastrointestinal Bleeding in Patients Treated with Direct-Acting Oral Anticoagulants

Direct-acting oral anticoagulants (DOACs), which have gained approval for stroke prevention in nonvalvular atrial fibrillation and treatment of venous thromboembolism, have become increasingly preferred over warfarin given their predictable pharmacodynamics, lack of required monitoring, and superior outcomes. Direct-acting oral anticoagulants have been shown to be associated with an increased frequency of gastrointestinal bleeding compared with warfarin, but the severity and characteristics of gastrointestinal bleeding in these patients is poorly understood.

We retrospectively evaluated electronic medical records of patients with gastrointestinal bleeding (n = 8496) from 2010-2016. We identified 61 patients with gastrointestinal bleeding episodes while treated with DOACs (rivaroxaban, dabigatran, or apixaban) and 123 patients with gastrointestinal bleeding while taking warfarin. We randomly selected a control group of 296 patients with gastrointestinal bleeding who were not receiving anticoagulation treatment from the same sample. Outcomes included the need for hospitalization, blood transfusion, endoscopic or surgical intervention, and 30-day mortality.

The DOAC and warfarin groups were similar in terms of age and underlying comorbidity (assessed using the Charlson Comorbidity Index), but the DOAC group had greater concomitant aspirin use. Gastrointestinal bleeding was classified as upper (n = 186), lower (n = 88), anorectal (n = 183), small bowel (n = 9), and indeterminate (n = 14). After adjusting for differences in baseline variables, the DOAC group had fewer hospitalizations and required fewer transfusions than the warfarin group. The DOAC and control groups were not statistically different for all outcomes. There were no significant mortality differences among groups.

Although prior studies have shown a higher frequency of gastrointestinal bleeding in patients treated with DOACs compared with warfarin, our data suggest that gastrointestinal bleeding in patients taking DOACs may be less severe. These differences occurred despite significantly greater concomitant aspirin use in the DOAC group compared with warfarin users.