ABSTRACT NUMBER: ESOC2026A1695 ETIOLOGY-DEPENDENT PROGNOSTIC ROLE OF ICAM-1 IN ACUTE ISCHEMIC STROKE

Abstract Background and aims Neuroinflammation plays a key role in brain injury after acute ischemic stroke (AIS). Intercellular adhesion molecule-1 (ICAM-1) reflects endothelial activation and microvascular dysfunction, but its prognostic value across stroke etiologies is not well defined. This study evaluated the etiology-dependent prognostic significance of serum ICAM-1 according to the TOAST classification. Methods We prospectively enrolled 118 patients with AIS. Blood samples were obtained within 24 hours of admission and serum ICAM-1 was measured by ELISA. Stroke etiology was classified as LAA (34.7%), SVO (29.7%), undetermined (22.9%), CE (8.5%), and other determined etiology (4.2%). Functional outcome at three months was assessed using the modified Rankin Scale (mRS), with mRS ≥3 defining poor outcome. Subtype-specific logistic regression analyses were performed. Results Serum ICAM-1 levels varied significantly across TOAST subtypes, being highest in cardioembolic stroke and lowest in SVO (147.8 ± 30.5 ng/ml in SVO, 196.8 ± 39.0 in LAA, 176.4 ± 63.0 in undetermined, 311.0 ± 119.2 in CE, and 183.5 ± 32.0 in other etiology). ICAM-1 was a significant independent predictor of poor functional outcome in large artery atherosclerosis (OR 1.05; 95% CI 1.02–1.08; p=0.002) and small vessel occlusion (OR 1.04; 95% CI 1.00–1.08; p=0.028). A non-significant trend was observed in undetermined etiology (OR 1.03; 95% CI 0.99–1.06; p=0.096), while no independent prognostic effect was detected in cardioembolic or other determined etiology subtypes. Conclusions ICAM-1 shows etiology-dependent prognostic behavior in AIS, predicting disability in LAA and SVO, while reflecting inflammatory severity in cardioembolic stroke. Conflict of interest No