Abstract TP456: Coated-platelets Levels After Subarachnoid Hemorrhage Predict Post-discharge Short-term Cognitive Outcome

Abstract

Introduction: Delayed cerebral ischemia (DCI) is a determinant of short-term and long-term morbidity after subarachnoid hemorrhage (SAH). DCI is likely due to neurohumoral activation and inflammation-thrombosis cross-talk during the acute phase. Coated-platelets (CP), a subset of procoagulant platelets, contribute to systemic thrombogenicity and are associated with recurrent ischemic stroke. Hypothesis: We hypothesized that high CP levels during first 3 weeks of SAH (acute hospitalization) would be associated with worse short-term clinical outcome. Methods: A prospective cohort of 28 patients with post-discharge clinical follow-up (average 12 weeks) was studied. Outcomes were assessed using modified Rankin Scale (mRS) and Montreal Cognitive Outcome Assessment (MOCA). Blood samples to measure CP levels were performed - 1) during acute hospitalization and 2) at follow-up visit (defined as patient’s baseline). Trend of CP during acute hospitalization was analyzed against weighted mean baseline CP level to test hypothesis. Results: Average age of cohort was 52.6±12.2 years with 71.5% women. During acute phase 9 (32.1%) patients developed symptomatic vasospasm and 14 (50%) had DCI on imaging. Baseline CP levels did not differ (p=0.118) between patients with MOCA ≥26 (41.3%, n=13) and MOCA <26 (29.5%, n=15). However, patients with MOCA <26 had significantly higher CP levels during first 5 days than baseline (50.4% vs 29.5%, p=0.0004). These levels decreased by 1.77%/day from 6-21 days as compared to 1.55%/day for patients with MOCA ≥26 (p=0.723). In contrast, 20 (71.4%) patients with mRS 0-2 had average baseline CP levels of 37.3% vs 8 (28.6%) with mRS 3-6 having CP levels of 31.7%. For patients with mRS 0-2 and mRS 3-6, CP levels increased from baseline during first 5 days after SAH by 10.3% and 16.5% respectively (not statistically significant). Rate of CP decrease during 6-21 days was 1.43%/day and 2.02%/day (p=0.259) for mRS 0-2 and mRS 3-6 respectively. Conclusion: Elevated CP levels during the acute phase of SAH are strongly associated with lower MOCA scores at 12 weeks but not with higher mRS assessment. These results suggest that increased thrombogenicity after SAH leads to cognitive impairment despite good physical outcomes.