Background: The optimal timing of surgery for aneurysmal subarachnoid hemorrhage (aSAH) remains controversial. This study aims to identify the optimal surgical window within 72 h of symptom onset.
Methods: Patients with aSAH who underwent surgical treatment within 72 h of onset were identified from the Chinese Multicenter Cerebral Aneurysm Database (2017-2020). Multivariable Cox and logistic regression models with restricted cubic splines (RCS) were used to assess associations between onset-to-treatment time and all-cause mortality and 2-year dependent survival, respectively.
Results: A total of 3560 patients with aSAH were included. During a mean follow-up of 30.9 ± 22.5 months, 521 deaths were recorded, yielding a 2-year mortality rate of 12.9%. The RCS analysis revealed a significant U-shaped relationship between onset-to-treatment time and all-cause mortality (χ2 = 5.88, df = 1, P = 0.015), as well as a significant overall association (χ2 = 6.73, df = 2, P = 0.035). The lowest risk of all-cause mortality was observed at 32.6 h after onset. A monotonically decreasing association was observed between onset-to-treatment time and 2-year dependent survival (χ2 = 3.70, df = 1, P = 0.055). Specifically, the risk of 2-year dependent survival declined rapidly with treatment delay during the first 12 h after onset and plateaued at approximately 32.6 h.
Conclusion: The time from onset to treatment demonstrated a nonlinear (U-shaped) association with all-cause mortality and a linear association with 2-year dependent survival, with the lowest estimated mortality risk observed at approximately 32.6 h after onset.
Keywords: Aneurysmal subarachnoid hemorrhage; Mortality; Onset-to-treatment time; Outcome.
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