Supplementary Material for: Microsurgical Treatment versus Endovascular Treatment for Ruptured Intracranial Aneurysms in Elderly Patients: A Multicenter Study in Northern China

Background: Management of ruptured intracranial aneurysms (RIAs) in elderly patients remains a major challenge in the treatment of cerebrovascular diseases. This study aims to provide a comprehensive analysis of the impact of microsurgical treatment (MST) and endovascular treatment (EVT) on the outcomes of elderly patients with RIAs in northern China.
Methods: We consecutively enrolled elderly patients with RIAs who underwent surgery in the Chinese Multicenter Cerebral Aneurysm Database (CMAD) from January 2017 to December 2020. In this study, in-hospital complications, survival, and functional outcomes were compared between MST and EVT after 1:1 propensity score matching (PSM). Kaplan-Meier survival analyses and Cox proportional hazards modeling identified factors associated with mortality in both groups. Logistic regression analyses identified 2-year survival-dependent risk factors, and subgroup analyses were conducted for key strata.
Results: 744 elderly patients with RIAs were enrolled in the study. 219 patients with MST after PSM were matched with 219 patients with EVT. Compared to EVT, MST had a higher 2-year mortality rate (32.8% vs. 20.5%, p=0.002), higher incidence of adverse discharge outcomes (48.4% vs. 32.4%, p=0.001), longer length of stay (LOS) (16 (12-24) vs. 15 (10-23), p=0.049), pneumonia (MST: 31.1%; EVT: 21.9%, p=0.030), and intracranial infection (9.6% vs. 2.7%, p=0.005). However, there was no difference in the 2-year survival-dependent outcome (22.7% vs 23.2%, p=0.924). Differences in risk factors for mortality and 2-year survival-dependent outcomes were observed between the MST and EVT groups in the elderly population. The negative association of EVT with risk of mortality was consistent across specific subgroups.
Conclusion: Elderly patients with RIAs who underwent EVT were significantly better than the MST group in terms of short-term functional outcomes, in-hospital complications, long-term survival, and LOS. However, there were no differences in the 2-year survival-dependent outcomes.