Time of surgery for aneurysmal subarachnoid hemorrhage in patients ≥70 years

Objective To establish a time-to-surgery threshold for elderly aneurysmal subarachnoid hemorrhage patients before the risk of mortality increases. Methods A cohort study using data with consecutive patients 70 years and older(N=743). Risk-adjusted restricted cubic splines modeled the mortality according to wait-time. The inflection point (in hours) when mortality began to increase was used to define early-time, middle-time and late-time surgery. To evaluate the robustness of this definition, outcomes among propensity-score matched non-middle surgical and middle-time surgical patients were compared using percent absolute risk differences. Results There were a total of 535 patients who met inclusion. Their mean age was 74.3 (4.38) years. Cox models with restricted cubic spline showed a statistically significant U shaped association for onset-to-surgery time with two year all cause mortality. 66 patients (12.3%) received middle-time surgery and 469 patients (87.7%) received early-time or late-time surgery. There were 60 (91%) patients in the middle-time surgery group matched to those in the non-middle-time group. Of the 60 matched patients who received surgery after less than 49 hours or more than 68 hours, 23 patients (38.3%) died within 24 months vs 14 patients (23.3%) of 60 who received surgery within 49 to 68 hours, for an absolute risk difference of 15% (95% CI, -2.68% to 31.50%). Conclusions In this study, onset-to-treatment time showed a U shaped association with 24 months all cause mortality. Early surgery was superior to delayed surgery in reducing death rate. Elderly patients with poor tolerance to ultra-early surgery in whom operation was probably postponed. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement Natural Science Foundation of Tianjin Municipality (Grant No. 20JCZDJC00300), the Tianjin Medical University General Hospital Clinical Research Program (Grant No. 22ZYYLCCG07) and the Tianjin Medical University Clinical Research Program (Grant No. 2018kylc008). ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The study design was approved by the Ethics Committee of Tianjin Medical University General Hospital (IRB2021-YX-178-01) and registered with the Chinese Clinical Trial Registry (registration number ChiCTR2100054014). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes The data that support the findings of this study are available from the corresponding author upon reasonable request.