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Updated: May 25, 2026
Evaluation of the Cognitive Performance of Hypertensive Patients with Silent Cerebrovascular Lesions
Published on: April 23, 2021
Cerebral hemodynamics and cognitive impairment: baseline data from the RECON trial
R S Marshall1, J R Festa, Y K Cheung
1Columbia University Medical Center, New York, NY, USA. rsm2@columbia.edu
Insights
Unihemispheral hemodynamic failure, indicated by increased oxygen extraction fraction (OEF), is linked to cognitive impairment in carotid occlusion patients. This finding is crucial for evaluating extracranial-intracranial bypass efficacy.
Area of Science:
- Neurology
- Neuroscience
- Cardiovascular Science
Background:
- Carotid artery occlusion can lead to hemodynamic compromise.
- Cognitive impairment is a potential consequence of cerebrovascular disease.
- Assessing hemodynamic status is vital for understanding neurological deficits.
Purpose of the Study:
- To investigate the association between unihemispheral hemodynamic failure and cognitive impairment.
- To analyze data from the Randomized Evaluation of Carotid Occlusion and Neurocognition (RECON) trial.
- To determine if increased oxygen extraction fraction (OEF) predicts cognitive deficits.
Main Methods:
- Compared patients with and without PET-confirmed OEF asymmetry (hemodynamic failure).
- Utilized a composite neurocognitive score derived from a standardized test battery.
- Employed multivariable regression analysis, stratifying by TIA vs. stroke as the qualifying event.
Main Results:
- No significant difference in cognitive scores between groups initially.
- After adjustment, hemodynamic failure was independently associated with cognitive impairment in TIA patients (p=0.040).
- Older age and right internal carotid artery (ICA) occlusion were also significant factors.
Conclusions:
- Unihemispheral hemodynamic failure is an independent predictor of cognitive impairment in carotid occlusion.
- This physiological parameter is key for testing the efficacy of extracranial-intracranial bypass.
- Findings highlight the importance of hemodynamic assessment in managing patients with carotid artery disease.
Objective:
To determine whether unihemispheral hemodynamic failure is independently associated with cognitive impairment among participants in the National Institute of Neurological Disorders and Stroke-sponsored, multicenter, randomized clinical trial, Randomized Evaluation of Carotid Occlusion and Neurocognition (RECON).
Methods:
Forty-three patients were randomized into RECON after recent symptomatic carotid artery occlusion and asymmetrically increased oxygen extraction fraction (OEF) by PET (OEF ratio >1.13), indicating stage II hemodynamic failure on the side of occlusion. The PET-positive patients were compared with 28 RECON-enrolled patients who met all clinical and radiographic inclusion/exclusion criteria but had no OEF asymmetry. A multivariable regression compared patients with PET OEF >1.13 or ≤1.13, stratifying by TIA vs. stroke as the qualifying event. The dependent variable was a composite neurocognitive score derived from averaging age-normalized z scores on a test battery that included global and internal carotid artery (ICA) side-relevant hemisphere-specific tests.
Results:
There were no differences in demographic, clinical, or radiologic characteristics between the PET-positive and PET-negative patients except for PET OEF asymmetry. The unadjusted average neurocognitive z score was -1.45 for the PET-positive and -1.25 for the PET-negative patients, indicating cognitive impairment in both groups but no difference between them (p = 0.641). After adjustment for age, education, side of occlusion, depression, and previous stroke, there was a significant difference between PET-positive and PET-negative patients among those with TIA as a qualifying event (average z score = -1.41 vs. -0.76, p = 0.040). Older age and right ICA side were also significant in this model.
Conclusion:
Hemodynamic failure is independently associated with cognitive impairment in patients with carotid occlusion. This finding establishes the physiologic parameter upon which the extracranial-intracranial bypass will be tested.
