Longitudinal trajectories of functional outcome following aneurysmal subarachnoid hemorrhage: a retrospective study

Aneurysmal subarachnoid hemorrhage (aSAH) is associated with high mortality and disability. However, post-discharge functional trajectories within the first year after the bleed remain poorly characterized. Understanding recovery patterns is essential for guiding clinical decisions, counseling families, and optimizing rehabilitation strategies.

We retrospectively analyzed consecutive adults with imaging-confirmed aSAH admitted to the neurocritical care unit (NCCU) of the University Hospital Zurich between January 2016 and June 2024. Patients who survived hospitalization and had standardized follow-up assessments at 3 and 12 months were included. Functional outcome was evaluated using the Glasgow Outcome Scale-Extended (GOSE). Improvement was defined as an increase in GOSE between 3 and 12 months. Predictors of functional improvement were identified using multivariable logistic regression and ordinal shift analysis.

Among 342 hospital survivors, 301 were eligible for trajectory analysis. Overall, 58.5% of the 301 eligible survivors improved on the GOSE between 3 and 12 months, while functional decline was infrequent (≈ 6%). Excluding patients at the extremes of the scale (GOSE3 = 1 or 8, who by definition could not improve on GOSE), improvement rates ranged from 38% to 71% and were the highest in patients with moderate disability (GOSE at three months = 4). A higher Charlson Comorbidity Index (CCI) showed a consistent association with a lower likelihood of functional improvement: this effect did not reach the multiplicity-adjusted significance threshold in the primary multivariable logistic regression model but was directionally similar and nominally significant in the ordinal shift sensitivity analysis.

Post-discharge recovery after aSAH is heterogeneous but often continues beyond three months. Pre-existing medical conditions seem to play an important role in outcome trajectories. Patients with moderate disability demonstrate the greatest potential for improvement, highlighting the importance of individualized rehabilitation and extended follow-up strategies after aSAH.