Indobufen versus Aspirin After CABG in Septuagenarians: A Propensity Score–Matched Cohort Study

Purpose: To compare the safety and efficacy of indobufen-based versus aspirin-based sequential antiplatelet therapy in septuagenarians undergoing coronary artery bypass grafting (CABG). Patients and Methods: Patients aged 70– 79 years who underwent CABG between 2020 and 2022 received either indobufen- or aspirin-based dual antiplatelet therapy (DAPT) (with clopidogrel) for 12 months, followed by monotherapy with their respective baseline agent (indobufen or aspirin) for an additional year. Propensity score matching (1:2, caliper 0.25 SD) balanced the baseline characteristics. The primary outcomes were 2-year major adverse cardiac and cerebrovascular events (MACCE) and Bleeding Academic Research Consortium (BARC) types 2, 3, or 5 bleeding. Results: Among 296 patients (indobufen, 46; aspirin, 250), 104 (indobufen, 36; aspirin, 68) were well matched. Before matching, indobufen showed similar 2-year MACCE risk to aspirin (6.5% vs 6.8%; subdistribution hazard ratio sHR 0.96, 95% CI 0.28– 3.28; p = 0.95) and lower BARC type 2, 3, or 5 bleeding (2.2% vs 6.8%; sHR 0.32, 95% CI 0.04– 2.38; p = 0.23). After matching, results remained consistent (MACCE 8.3% vs 10.3%; sHR 0.81, 95% CI 0.21– 3.10; p = 0.76; bleeding 2.8% vs 11.8%; sHR 0.24, 95% CI 0.03– 1.87; p = 0.14). Indobufen reduced clinically relevant bleeding by 9.0% (number needed to treat NNT ≈ 11) without compromising ischemic outcomes. Conclusion: Indobufen-based sequential therapy provided ischemic protection similar to that of aspirin, while showing a favorable bleeding profile in septuagenarians undergoing CABG. For individuals with a high bleeding risk or aspirin intolerance, indobufen may represent a practical alternative. Larger prospective studies focusing on geriatric outcomes are warranted. Keywords: antiplatelet therapy, coronary revascularization, older adults, bleeding risk, major adverse cardiac and cerebrovascular events, secondary prevention