Early rehabilitation initiation after aneurysmal subarachnoid haemorrhage: evaluation of mortality and functional outcomes.

INTRODUCTION: Evidence regarding the optimal timing of rehabilitation after aneurysmal subarachnoid haemorrhage (aSAH) remains limited. In this study, we aimed to evaluate clinical outcomes associated with initiating rehabilitation within 48 h after aneurysm securing. PATIENTS AND METHODS: We conducted a retrospective cohort study emulating a target trial using the Diagnosis Procedure Combination claims database (651 acute-care hospitals), which contains administrative data with limited clinical granularity. We included adults (≥18 years) with aSAH who underwent endovascular coiling or surgical clipping on hospital day 1 and had prestroke mRS scores of 0-2. Early rehabilitation was defined as initiation within 48 h after aneurysm securing; the comparator was initiation after 48 h. Using a clone-censoring-weighting approach, we estimated per-protocol hazard ratios for 30-day mortality and poor functional outcome (mRS scores of 3-6). Sensitivity analyses were conducted using alternative initiation thresholds (72, 96 and 120 h). RESULTS: Among 7544 patients (mean age, 62.6 years; 69.7% women), crude 30-day mortality was 2.6% in the early initiation group and 1.5% in the deferred initiation group. In the per-protocol analysis, early rehabilitation was associated with higher 30-day mortality (hazard ratio [HR], 1.82; 95% CI, 1.21-2.63) and a higher risk of poor functional outcome (HR, 1.31; 95% CI, 1.08-1.55). This association was attenuated when "early" was defined after 72 h (mortality HR, 1.34; 95% CI, 0.87-2.07). DISCUSSION: Initiating rehabilitation within 48 h after aneurysm securing was associated with worse short-term outcomes, whereas deferring initiation until after 72 h attenuated the excess risk. CONCLUSIONS: These findings suggest that the first 48 h may represent a higher-risk window for routine rehabilitation initiation in acute aSAH care.