Five-variable admission model predicts 90-day outcomes in 245 aneurysmal subarachnoid hemorrhage patients

BACKGROUND: Early prognostic stratification of aneurysmal subarachnoid hemorrhage (aSAH) is clinically important. We developed and temporally validated an admission-based prediction model for 90-day outcomes in a cohort of patients with aSAH. METHODS: Consecutive treatment-eligible patients with aSAH, managed at a single center between January 2021 and December 2025, were retrospectively analyzed. Patients treated from 2021?2023 and 2024?2025 comprised the development and temporal validation cohorts, respectively. Prediction models were developed using admission variables, including age, pre-morbid modified Rankin Scale (mRS) score, World Federation of Neurosurgical Societies grade, modified Fisher grade, and intracerebral hemorrhage on initial computed tomography. The primary outcome was a 90-day mRS score of 0?3 points. A sensitivity model was constructed for 90-day mRS scores of 0?2. RESULTS: A total of 245 patients were included (development cohort: 160; validation cohort: 85); 107 patients were aged ? 70 years. For mRS 0?3, the model demonstrated good discrimination in both the development and validation cohorts (area under the curve [AUC]: 0.917 and 0.868), while mRS 0?2 had corresponding AUCs of 0.920 and 0.840, respectively. Among patients aged ? 70 years, the validation AUCs were 0.842 and 0.768 for mRS scores of 0?3 and 0?2, respectively. Calibration was acceptable overall but less stable in older patients. CONCLUSIONS: In an aSAH cohort with a substantial proportion ofpredominantly older patients, an admission-based five-variable model provided 90-day outcome prediction with good discrimination on temporal validation. This tool may facilitate early risk stratification at admission, pending multicenter external validation.