Abstract TP153: Cognitive Profile in Patients With Hemodynamic Failure Due to Severe Carotid Stenosis

Abstract

Background: Severe carotid stenosis can reduce cognition due to hypoperfusion. Published cognitive profiles for vascular disease are variable, however, precluding identification of hemodynamic failure as a specific cause. We investigated the relationship among carotid stenosis, hemodynamic failure, and cognition by characterizing cognition in patients with severe carotid stenosis, with and without hemodynamic failure. Methods: Sixty-one patients (18 with TIA, none with stroke) with ≥80% carotid stenosis were drawn from two study cohorts, RECON and BFC 1 . Hemodynamic status was assessed using oxygen extraction fraction by positron emission tomography (RECON) or mean flow velocity by transcranial Doppler (BFC) and dichotomized into normal (n=30) vs impaired (n=31). Cognition was assessed with 16 tests. Sixteen linear regressions, one for each cognitive test, were performed to assess the influence of hemodynamic failure on test scores, adjusting for side of occlusion, depression, age, gender, education, and study cohort. Multiple comparisons were adjusted using false discovery rate (FDR) correction. Results: Hemodynamic failure was a significant independent predictor for Rey Complex Figure Test-Copy (RCFT-C, p=0.007), RCFT-Delayed Recall (RCFT-D, p=0.003), and Trail Making Test-B (TMT-B, p=0.006) and remained so after FDR correction. The other tests were not predicted by hemodynamic status. Conclusions: Tests of mental flexibility, visuospatial skill, and organization were sensitive to hemodynamic failure in patients with severe carotid stenosis. A larger sample is required to validate this cognitive profile in such patients. Cognitive assessment with RCFT-C, RCFT-D, and TMT-B may detect the effects of hemodynamic failure specific to large vessel disease, having research and treatment utility. 1 NINDS NS048212 (Randomized Evaluation of Carotid Occlusion and Neurocognition -RECON), R01NS076277 (Blood Flow and Cognition - BFC)