Abstract WP073: Unmasking Sex Differences: Circulating Biomarker Signatures of Intraplaque Hemorrhage in Chronic Cerebral Artery Occlusion

Background: Chronic cerebral artery occlusion (CCAO) is a major cause of ischemic stroke. Intraplaque hemorrhage (IPH), a marker of plaque instability, is linked to higher cerebrovascular risk, but its prevalence, risk factors, and sex-specific differences in CCAO remain unclear. This study assessed IPH prevalence in anterior CCAO (ACCAO), its associations with sex, clinical and biomarker profiles, and its relationship to stroke severity and short-term outcomes. Methods: We retrospectively analyzed 210 ACCAO patients. High-resolution vessel wall MRI identified occlusion site and IPH. Demographics, vascular risks, inflammatory markers, lipid profiles, and biochemistry were collected. IPH vs. non-IPH (NIPH) groups were compared; logistic regression identified independent factors; sex–biomarker interactions were examined. Correlations and ROC analyses evaluated inflammatory indices for admission NIHSS and 30-day mRS. Results: IPH was present in 45.7% (96/210) of patients. The IPH group had more males (69.5% vs. 30.5%, P<0.05) and more internal carotid artery occlusions (60.4%), whereas the NIPH group more often had MCAO (50.9%, P<0.05). Poor 30-day outcomes were more frequent in IPH vs. NIPH (20.8% vs. 10.5%, P=0.038). Platelet count, apoA1, and creatinine differed significantly between groups. In IPH, males had higher monocyte counts, lipid levels, and apoB; in NIPH, females had higher lymphocyte counts and HDL (all P<0.05). Multivariate analysis in IPH showed male sex associated with elevated monocytes (OR=3.06), hemoglobin (OR=3.17), and uric acid (OR=2.46). Interaction analysis revealed sex modified the associations of hemoglobin (OR=0.39) and triglycerides (OR=0.34) with IPH risk, with stronger effects in females. Across the cohort, NLR, PLR, and SII correlated with higher NIHSS and mRS scores (r=0.179–0.290, P<0.05). ROC analysis showed PLR (AUC=0.702) and PAR (AUC=0.714) best predicted severe stroke in IPH, while SIRI (AUC=0.729) and AISI (AUC=0.678) were most predictive in NIPH. Conclusions: Nearly half of patients with ACCAO had IPH, with male sex as a major risk factor. Sex-specific biomarker interactions suggest differing pathophysiological mechanisms. Inflammatory indices were strongly associated with stroke severity and outcomes. IPH detection by HR-MRI, combined with sex and inflammatory profiles, may enhance prognostic risk stratification and guide individualized management in CCAO.