Considering future research
In this study, peptic ulcer disease was a proportionally less common cause of upper GI bleeding for warfarin at 18%, compared with DOACs at 39%. At the same time, the absolute propensity-weighted incidence rates of peptic ulcer–induced bleeding were similar, with 0.3 events per 100 person-years for both groups.
“As warfarin is not thought to induce peptic ulcer disease but rather promote bleeding from pre-existing lesions, one explanation may be that peptic ulcer disease almost always leads to overt bleeding in anticoagulated patients, while other lesions, such as mucosal erosions and angiodysplasias, may be more likely to lead to overt bleeding in warfarin patients due to a potentially more intense anticoagulation,” Dr. Ingason said.
Dr. Ingason and colleagues now plan to compare GI bleeding severity between warfarin and DOACs. Previous studies have suggested that GI bleeding may be more severe in patients receiving warfarin than in those receiving DOACs, he said.
In addition, large studies with manual verification of GI bleed events could better estimate the potential differences in the sources of upper and lower bleeding between warfarin and DOACs, Dr. Ingason noted.
“Some DOACs, specifically dabigatran, are known to have a mucosal effect on the luminal GI tract, as well as a systemic effect,” Dr. Abraham said. “This pharmacologic effect may contribute to an increase in lower gastrointestinal bleeding in the setting of colonic diverticulosis or mucosal injuries from inflammatory processes.”
Ongoing research should also look at different ways to reduce anticoagulant-related GI bleeding among cardiac patients, she noted.
“Our research group continues to study the risk of cardiac and bleeding adverse events in patients prescribed to DOACs compared to those patients who receive a left atrial appendage occlusion device,” Dr. Abraham said. “This device often permits patients at high risk of GI bleeding to transition off anticoagulant and antiplatelet drugs.”
The study was funded by the Icelandic Centre for Research and the Landspitali University Hospital Research Fund. The funders had no role in the design, conduct, or reporting of the study. The authors declared no competing interests. Dr. Abraham reported no relevant financial relationships.
A version of this article first appeared on Medscape.com.