A 68-year-old man with nonvalvular atrial fibrillation (paroxysmal), hypertension, and type 2 diabetes has a CHA₂DS₂‑VASc score of 3 (age 65-74 = 1, HTN = 1, DM = 1). eGFR is 60 mL/min/1.73 m²; no moderate-to-severe mitral stenosis or mechanical valve. What is the most appropriate next step to reduce stroke risk?