Non-Vitamin K Antagonist Oral Anticoagulants and the Gastrointestinal Bleeding Risk in Real-World Studies.

In the present study, we aimed to provide evidence from high-quality real world studies for a comprehensive and rigorous analysis on the gastrointestinal bleeding (GIB) risk for non-vitamin K antagonist oral anticoagulants (NOACs). We performed a systematic search of MEDLINE, EMBASE and PUBMED, and of 286 records screened, we included data from 11 high-quality real-world studies, coordinated by independent research groups over the last 3 years, that reported major GIB events in patients given NOACs or vitamin K antagonists for patients with nonvalvular atrial fibrillation. The lowest risk of gastrointestinal bleeding was with apixaban compared with warfarin (hazard ratio (HR) for GIB for apixaban ranging between 0.45 (95% confidence interval (CI) 0.34 to 0.59) and 1.13 (95% CI 0.79 to 1.63)). Apixaban was associated with a lower risk of GI bleeding than dabigatran ((HR ranging between 0.39 (95% CI 0.27 to 0.58) and 0.95 (95% CI 0.65 to 1.18)) or rivaroxaban ((HR ranging between 0.33 (95% CI 0.22 to 0.49) and 0.82 (95% CI 0.62 to 1.08)). The results of our study confirm a low or a similar risk for major GIB between patients receiving apixaban or dabigatran compared with warfarin, and apixaban appears to be associated with the lowest risk of GIB.