ABSTRACT NUMBER: ESOC2026A2358 PREDICTORS OF FAVORABLE OUTCOME IN MEDICALLY MANAGED VERTEBROBASILAR ARTERY OCCLUSION: ANALYSIS FROM POOLED RANDOMIZED CONTROLLED TRIALS

Abstract Background and aims While EVT improves VBAO outcomes, substantial patients receive medical management alone. Identifying predictors of favorable outcome in medically managed patients may inform treatment decisions. We examined baseline predictors in VBAO patients receiving medical management. Methods IPD from patients randomized to medical management in BASICS, BEST, ATTENTION, BAOCHE were analyzed. Predictors: demographics, stroke characteristics (NIHSS, pc-ASPECTS, pre-mRS, time, occlusion site), comorbidities, IVT. Primary outcome: mRS 0-3 at 90 days. Univariable and multivariable logistic regression. Model discrimination assessed by C-statistic. Results Among 432 medically managed patients (mean age 65.9±11.4y; 28.5% female), 128 (29.6%) achieved favorable outcome. Favorable outcome patients had lower NIHSS (12 vs 26), higher pc-ASPECTS (10 vs 9), were younger (62.1 vs 67.5y), and had less proximal occlusions (24.0% vs 39.7%; all P<0.001). Independent predictors included age (OR 0.57/10y, 95% CI 0.45-0.72), NIHSS (OR 0.66/5pts, 95% CI 0.58-0.74), pc-ASPECTS (OR 1.29/pt, 95% CI 1.07-1.56), proximal occlusion (OR 0.31, 95% CI 0.16-0.61), and diabetes (OR 0.43, 95% CI 0.22-0.83). Model C-statistic was 0.817. Conclusions In medically managed VBAO, favorable outcomes are predicted by younger age, lower NIHSS, higher pc-ASPECTS, and distal occlusion. The overall low favorable outcome rate (29.6%) underscores the poor prognosis without EVT. Conflict of interest None