Net Clinical Benefit of Non-Vitamin K Antagonist vs Vitamin K Antagonist Anticoagulants in Elderly Patients with Atrial Fibrillation

Background: The risks of thromboembolic and hemorrhagic events in patients with atrial fibrillation both increase with age; therefore, net clinical benefit analyses of anticoagulant treatments in the elderly population are crucial to guide treatment. We evaluated the 1-year clinical outcomes with non-vitamin-K antagonist and vitamin K antagonist oral anticoagulants (NOACs vs VKAs) in elderly (≥75 years) patients with atrial fibrillation in a prospective registry setting. Methods: Data on 3825 elderly patients were pooled from the PREFER in AF and PREFER in AF PROLONGATION registries. The primary outcome was the incidence of the net composite endpoint, including major bleeding and ischemic cardiovascular events on NOACs (n = 1556) compared with VKAs (n = 2269). Results: The rates of the net composite endpoint were 6.6%/year with NOACs vs 9.1%/year with VKAs (odds ratio [OR] 0.71; 95% confidence interval [CI], 0.51-0.99; P =.042). NOAC therapy was associated with a lower rate of major bleeding compared with VKA use (OR 0.58; 95% CI, 0.38-0.90; P =.013). Ischemic events were nominally reduced too (OR 0.71; 95% CI, 0.51-1.00; P =.050). Major bleeding with NOACs was numerically lower in higher-risk patients with low body mass index (BMI; OR 0.50; 95% CI, 0.22-1.12; P =.07) or with age ≥85 years (OR 0.44; 95% CI, 0.13-1.49; P =.17). Conclusions: Our real-world data indicate that, compared with VKAs, NOAC use is associated with a better net clinical benefit in elderly patients with atrial fibrillation, primarily due to lower rates of major bleeding. Major bleeding with NOACs was numerically lower also in higher-risk patients with low BMI or age ≥85 years.