Non–vitamin K antagonist oral anticoagulants (NOACs) as a group have a similar risk of major gastrointestinal bleeding compared with conventional anticoagulation, although subgroup analyses showed increased odds of major bleeding associated with dabigatran and rivaroxaban, according to a study in Clinical Gastroenterology and Hepatology.
Corey S Miller, MD, from the Department of Medicine, McGill University in Montreal, and colleagues searched multiple medical databases through January 2016 for randomized trials comparing NOACs with conventional anticoagulants. The meta-analysis ultimately included 43 randomized trials, 28 of which (129,357 patients) provided data on gastrointestinal bleeding. Major gastrointestinal bleeding was the primary outcome, and clinically relevant nonmajor bleeding and upper and lower gastrointestinal bleeding were the secondary outcomes.
The researchers found no difference between NOACs and conventional anticoagulants regarding the risk of major bleeding (1.5% vs 1.3%, respectively; OR, 0.98), clinically relevant nonmajor bleeding (0.6% vs 0.6%, respectively; OR, 0.93), upper gastrointestinal bleeding (1.5% vs 1.6%, respectively; OR, 0.96), or lower gastrointestinal bleeding (1.0% vs 1.0%, respectively; OR, 0.88).
However, dabigatran (2.0% vs 1.4%, respectively; OR, 1.27) and rivaroxaban (1.7% vs 1.3%, respectively; OR, 1.40) were associated with an increased risk of major gastrointestinal bleeding, compared with conventional anticoagulation. No difference was found for apixaban (0.6% vs 0.7%, respectively; OR, 0.81) or edoxaban (1.9% vs 1.6%, respectively; OR, 0.93).
“Our primary outcome showed no significant difference in major gastrointestinal bleeding when NOACs were compared collectively with conventional anticoagulation,” stated the researchers. “Prespecified subgroup analyses, however, showed increased odds of major gastrointestinal bleeding associated with dabigatran and rivaroxaban, with 27% and 40% relative increases, respectively. No such difference was observed for factor Xa inhibitors apixaban or edoxaban.”
The investigators noted that current gastroenterology guidelines have not adequately addressed the risk of NOAC-associated bleeding or the potential for mitigating this risk.
“There may be benefit in risk-stratifying patients requiring long-term anticoagulation by risk of gastrointestinal bleeding,” Dr Miller’s group commented.
Miller CS, Dorreen A, Martel M, Huynh T, Barkun AN. Risk of gastrointestinal bleeding in patients taking non–vitamin K antagonist oral anticoagulants: a systematic review and meta-analysis. Clin Gastroenterol Hepatol. 2017;15:1674-1683. doi: 10.1016/j.cgh.2017.04.031