Pre-Thrombolysis Biological Correlates of Admission Glasgow Coma Scale in Older Adults with Acute Ischemic Stroke: A Retrospective Single-Center Cohort Study.

Background and Objectives: Biological correlates of baseline clinical responsiveness remain incompletely characterized in older adults with acute ischemic stroke treated with intravenous thrombolysis. We evaluated associations between admission Glasgow Coma Scale (GCS) and pre-thrombolysis hematologic, inflammatory, iron-status, and micronutrient parameters. Materials and Methods: This retrospective single-center cohort included 95 unique patients aged ≥65 years, all treated with intravenous alteplase between 2020 and 2024. Admission GCS ranged from 11 to 14. Spearman correlations used original GCS scores. Principal proportional odds models used ordered GCS categories of 11-12, 13, and 14, and were adjusted for age, sex, and admission National Institutes of Health Stroke Scale (NIHSS), with false discovery rate corrections. Sensitivity analyses additionally considered clinician-documented aphasia, congestive heart failure, atrial fibrillation, and reperfusion status for 24 h GCS change. Results: Admission GCS correlated most strongly with RDW-CV (rho = -0.843; 95% bootstrap CI, -0.892 to -0.774) and MCV (rho = 0.779; 95% CI, 0.668 to 0.866). Principal adjusted odds ratios per one-SD increase were 5.68 for hemoglobin, 3.01 for log-transformed ferritin, 4.71 for serum iron, 4.71 for log-transformed vitamin B12, 0.20 for C-reactive protein, and 0.019 for RDW-CV (all FDR-adjusted p < 0.001). Association directions remained consistent in sensitivity analyses. MCV showed an exploratory nonlinear association. No biomarker was associated with the direction of 24 h GCS change after FDR correction, including reperfusion-adjusted models. Conclusions: Pre-thrombolysis biological parameters were concurrently associated with baseline GCS within this single-center cohort and restricted GCS range. These associations do not establish causality, independence from unmeasured lesion location or infarct volume, predictive utility, or early neurological recovery. Prospective external validation is required.