Patients with atrial fibrillation (AF) and stable coronary artery disease (CAD) often require long-term antithrombotic therapy. The AFIRE randomized clinical trial, published in JAMA Cardiology, evaluated rivaroxaban monotherapy versus rivaroxaban plus an antiplatelet agent. A post hoc secondary analysis stratified patients by age to assess differences in efficacy and safety. The trial enrolled 2,215 participants in Japan from 2015 to 2018. Eligible patients had undergone coronary revascularization one or more years earlier or had angiographically confirmed CAD not requiring revascularization.

Participants were categorized as younger than 70 years, 70 to 74 years, 75 to 79 years, or 80 years and older. Major adverse cardiovascular event rates per patient-year for monotherapy versus combination therapy were 3.2% vs 4.3% (<70 years), 3.2% vs 2.8% (70–74 years), 3.8% vs 5.3% (75–79 years), and 6.2% vs 10.3% (≥80 years). The hazard ratio was lowest in the oldest group at 0.61 (95% CI, 0.40–0.93).

Major bleeding rates for monotherapy versus combination therapy were 0.5% vs 2.3% (<70 years), 2.2% vs 2.4% (70–74 years), 1.1% vs 2.1% (75–79 years), and 2.9% vs 4.3% (≥80 years). The hazard ratio for major bleeding was lowest in patients younger than 70 years at 0.23 (95% CI, 0.06–0.79). There was no statistically significant interaction by age for efficacy (P=.51) or safety (P=.33).