NOACs preferred over warfarin for nonvalvular atrial fibrillation in patients also taking low-dose aspirin

Reference

Bennaghmouch N, de Veer AJWM, Bode K, et al. Efficacy and safety of the use of non-vitamin K antagonist oral anticoagulants in patients with nonvalvular atrial fibrillation and concomitant aspirin therapy a meta-analysis of randomized trials. Circulation 2018;137(11):1117-1129.

Synopsis

Many patients with atrial fibrillation have a separate indication for aspirin. This meta-analysis performed a thorough search of several databases and identified 4 randomized trials with a total of 21,722 patients who had NVAF and were taking antiplatelet therapy (most commonly low-dose aspirin) for cardiovascular prevention. Each of the studies randomized patients to receive either warfarin or a NOAC such as edoxaban, apixaban, rivaroxaban, or dabigatran. The studies had between 1.8 and 2.8 years of follow-up. The mean age of included patients was between 70 years and 72 years, approximately one-third were women, and between 10% and 55% had experienced a previous stroke. After performing a random effects meta-analysis, the authors found that patients randomized to receive NOACs were less likely to experience a stroke or systemic embolism (hazard ratio [HR] 0.78; 95% CI 0.67 - 0.91) or vascular death (HR 0.85; 0.76 - 0.93) than those randomized to receive warfarin. There was a trend toward a higher risk of myocardial infarction in the NOAC group, primarily driven by the one dabigatran trial (HR 1.2; 0.97 - 1.4), but a trend toward fewer major hemorrhages with NOACs (HR 0.83; 0.69 - 1.01). Patients randomized to receive a NOAC were significantly less likely to experience an intracranial hemorrhage (HR 0.38; 0.26 - 0.56). There was minimal to moderate heterogeneity for most outcomes, although the measure used (I2) is unreliable with only 4 studies