Supplementary Material for: Evaluating the Safety of Stent-Assisted Endovascular Treatment for Unruptured Cerebral Aneurysms in Older Adults: Emphasizing the Role of Antiplatelet Therapy

Introduction: This study aimed to compare the outcomes and safety in patients aged ≥75 years and those aged <75 years who underwent stent-assisted endovascular treatment for unruptured cerebral aneurysms, specifically focusing on perioperative antiplatelet therapy (APT). Methods: This multicenter retrospective study comprised patients who underwent stent-assisted coiling (SAC) or flow diverter stent (FDS) placement for unruptured cerebral aneurysms. The primary outcome was defined as the composite outcomes of perioperative thromboembolic events, bleeding events, or death. Results: Among 632 patients, 533 (84.3%) were aged <75 years and 99 (15.6%) were aged ≥75 years. No significant differences were observed in the dual APT duration. The primary outcome occurred in 14.3% of patients aged <75 years and in 14.1% of those aged ≥75 years, with no significant difference (P=1.0). The composites of the primary outcome, including thromboembolic events, bleeding events, and death differed insignificantly. Similar findings were observed when the primary outcomes for SAC (12.7% vs. 11.5%, P=0.95) and FDS (17.5% vs. 18.4%, P=1.0) were analyzed. The 30-day, 1-year, and 2-year cumulative event-free survival rates for the primary outcome were 89.5, 87.2%, and 85.2%, respectively, in patients aged <75 years, and 90.9%, 88.7%, and 87.0%, respectively, in those aged ≥75 years. These trends were similar (log-rank test, P=0.92). Conclusion: No significant differences were observed in the rates of the primary outcomes between patients aged <75 years and those aged ≥75 years. Therefore, refraining from stent-assisted treatment for unruptured aneurysms based solely on age might be inappropriate.