HealthDay News — Concomitant use of a nonsteroidal anti-inflammatory drug (NSAID) or aspirin in patients with venous thromboembolism receiving anticoagulant therapy is tied to increased risk of clinically relevant and major bleeding, according to a study published in JAMA Internal Medicine.
Bruce L. Davidson, MD, from the University of Washington in Seattle, and colleagues analyzed data from 8,246 patients enrolled in the EINSTEIN deep vein thrombosis and pulmonary embolism clinical trials from 2007 to 2009, which compared rivaroxaban with enoxaparin-vitamin K antagonist (VKA) treatment.
The researchers examined bleeding event rates during exposure to NSAID and aspirin therapy compared with periods of nonexposure.
During concomitant NSAID-anticoagulant treatment, clinically relevant bleeding occurred at an event rate of 37.5 per 100 patient-years versus 16.6 per 100 patient-years during periods of anticoagulant use only (hazard ratio [HR], 1.77; 95% CI: 1.46-2.14), the researchers found. Major bleeding events occurred at rate of 6.5 versus 2.0 per 100 patient-years during nonuse (HR, 2.37; 95% CI: 1.51-3.75).
For concomitant aspirin-anticoagulant treatment compared with aspirin nonuse, clinically relevant bleeding occurred at an event rate of 36.6 vs. 16.9 per 100 patient-years (HR, 1.70; 95% CI: 1.38-2.11), whereas major bleeding occurred at an event rate of 4.8 versus 2.2 per 100 patient-years (HR, 1.50; 95% CI: 0.86-2.62).
Similar increases in risk for clinically relevant and major bleeding were seen with rivaroxaban and enoxaparin-VKA anticoagulation regimens.
“Among patients with venous thromboembolism receiving anticoagulant therapy, concomitant use of an NSAID or aspirin is associated with an increased risk of clinically relevant and major bleeding,” the researchers wrote.