NOACs, aspirin carry similar risks of major bleeding, intracranial hemorrhage
Risks of major bleeding and intracranial hemorrhage were similar with therapeutic doses of the non-vitamin K oral anticoagulants (NOACs) apixaban and dabigatran versus with aspirin, a review of nine trials with more than 26,000 participants found.
Rates of major bleeding for apixaban and dabigatran are similar to those for low-dose aspirin, but rates with rivaroxaban are higher, according to a systematic review.
To assess the difference in bleeding rates between non-vitamin K oral anticoagulants (NOACs) and single antiplatelet therapy, researchers searched databases for trials that compared the treatments for a minimum duration of three months. A total of nine randomized controlled trials with 26,224 participants were included in the review. All of the trials used aspirin as an antiplatelet therapy (81 or 100 mg once daily in eight trials and 81 to 324 mg once daily in one trial). Average patient age was 67 years, trial populations were 58% male on average, and mean follow-up time across trials was 20 months. Findings were published by Annals of Internal Medicine on Feb 10.
A total of 566 patients (2.16%) had major bleeding and 172 patients (0.66%) had intracranial hemorrhage. Apixaban and dabigatran were each associated with similar rates of major bleeding compared with aspirin (risk differences [RD], 0.0 percentage point [95% CI, −1.3 to 2.6 percentage points] and 0.5 percentage point [95% CI, −2.1 to 19.6 percentage points], respectively) and similar rates of intracranial hemorrhage (RDs, −0.2 percentage point [95% CI, −0.6 to 1.4 percentage points]and 0.0 percentage point[95% CI, −1.1 to 24.5 percentage points] respectively). Compared to aspirin, rivaroxaban had slightly higher rates of both major bleeding and intracranial hemorrhage (RDs, 0.9 percentage point [95% CI, −0.1 to 3.7 percentage points] and 0.3 percentage point [95% CI, −0.1 to 79.7 percentage points], respectively). Six of the nine trials were at low risk of bias, and the evidence of certainty for all trials ranged from low to moderate.
The researchers noted that the analyses contained few events overall and cautioned that “clinically relevant differences could not always be excluded because of imprecision.” The review also did not include studies comparing edoxaban versus single antiplatelet therapy or studies comparing NOACs versus antiplatelets other than aspirin. “Whether our results can be extrapolated to these scenarios is unknown,” they wrote.