Abstract DP085: Stage-Specific Cognitive Impairment and Biomarker Profiles Along the Intracranial Atherosclerosis Continuum

Background: Intracranial atherosclerosis (ICAS) encompasses a severity continuum from subclinical plaque to flow-limiting stenosis and stroke. While associated with cognitive impairment and dementia, the stage-specific contribution of the ICAS continuum remains undefined. Methods: This cross-sectional analysis utilized baseline data from a multicenter cohort study. We enrolled patients with radiologically confirmed ICAS and ICAS-free controls. Participants underwent comprehensive assessments, including cognitive evaluation via a comprehensive neuropsychological battery, quantification of plasma Alzheimer’s disease（AD） biomarkers (Aβ42/40 ratio, pTau217, glial fibrillary acidic protein [GFAP], neurofilament light chain [NfL]) using Simoa technology, and evaluation of cerebral small vessel disease (CSVD) burden assessed by a standardized MRI visual rating scale. Results: Among 506 participants (mean age 60±11years; 53.4% male), stratified by ICAS stages: 99 were ICAS-free controls, 84 had asymptomatic ICAS (aICAS) with