Major bleeding, mortality risks after VTE similar on DOACs or warfarin

Direct oral anticoagulants (DOACs) and warfarin carried similar risks of death and major bleeding in the first 90 days of venous thromboembolism (VTE) treatment, a recent multicenter study found.

Researchers used U.S. and Canadian databases to retrospectively assess 59,525 adults who, between Jan. 1, 2009, and March 31, 2016, had incident VTE and a prescription for a DOAC or warfarin within 30 days of diagnosis. The propensity-matched cohort consisted of 12,489 DOAC users and 47,036 warfarin users.

Primary outcomes were hospital admission or ED visit for major bleeding and all-cause mortality within 90 days of treatment. Results were published online on Oct. 17 by The BMJ.

Overall, 1,967 (3.3%) patients had a major bleeding event, and 1,029 (1.7%) died over a mean follow-up of 85.2 days. The risk of major bleeding was similar for patients taking DOACs compared to those taking warfarin (pooled hazard ratio, 0.92; 95% CI, 0.82 to 1.03). The risk of death was also similar between DOAC and warfarin users (pooled hazard ratio, 0.99; 95% CI, 0.84 to 1.16).

Overall results for both outcomes were similar irrespective of chronic kidney disease status, age, and sex. Results also remained unchanged after 180 days of follow-up.

The authors noted limitations of the study, such as its observational nature and the possibility of unmeasured confounders. They noted that the safety of DOAC treatment of VTE beyond 180 days remains uncertain, adding that 95% of DOAC users in the study were taking rivaroxaban, so further study of other DOAC agents is needed.

“… [G]iven the absence of an increased bleeding risk and the advantages associated with its use particularly around frequency of monitoring and dosing, our results suggest that DOACs may be considered as a treatment option for patients with venous thromboembolism who are candidates for anticoagulation,” they wrote.