Upper, major GI bleeding rates higher with warfarin vs DOACs

Treatment with warfarin appears to lead to a higher frequency of upper and major gastrointestinal (GI) bleeding as compared with direct oral anticoagulants (DOACs), a study has found.

The study used data from the National University Hospital of Iceland and four regional hospitals and included patients who had received a prescription for oral anticoagulation from 2014-2019.

Researchers used Cox regression with inverse probability weighting to yield balanced study groups and compare rates of overall, major, upper, and lower GI bleeding between groups.

Results showed that compared with DOACs, warfarin correlated with higher rates of upper GI bleeding (1.7 vs 0.8 events per 100 person-years; hazard ratio [HR], 2.12, 95 percent confidence interval [CI], 1.26–3.59). However, there was no significant between-group difference in the rates of lower GI bleeding.

The observations persisted in an analysis that assessed DOACs individually. Specifically, warfarin was associated with elevated rates of upper GI bleeding relative to apixaban (HR, 2.63, 95 percent CI, 1.35–5.13), dabigatran (HR, 5.47, 95 percent CI, 1.87–16.05), and rivaroxaban (HR, 1.74, 95 percent CI, 1.00–3.05).

Warfarin was also associated with greater rates of major GI bleeding as compared with apixaban (2.3 vs 1.5 events per 100 person-years; HR, 1.79, 95 percent CI, 1.06–3.05). Meanwhile, overall and major GI bleeding rates were similar between warfarin and DOAC users.