Introduction: Carotid revascularization procedures are effective in stroke prevention in appropriately selected patients. We sought to understand the effects of the carotid intervention on cognitive function in a well-defined cohort of prospectively recruited patients. Methods: A total of 170 consecutive patients undergoing carotid intervention for severe carotid stenosis were recruited. Patients received neuropsychometric testing preintervention, and at 1, 6, and 12 months postoperative. Patients were screened with the Mini-Mental State Examination. Rey Auditory Verbal Learning test (RAVLT) test was the primary outcome measure and multiple cognitive tests were used to evaluate executive function. Paired t test and McNemar test were performed to compare age-adjusted and education-adjusted postoperative scores at the individual time point with the preoperative scores. Results: Our patients had a high prevalence of cardiovascular risks and 51.2% of whom were symptomatic. The usages of statin and antiplatelet were high (88.8% and 69.4%, respectively). A total of 140 patients had 1 or more postoperative neuropsychometric tests in addition to their preoperative tests were included. The average RAVLT preoperative score was lower (z=−0.79, SD=1.3, confidence interval: −1 to −0.53) than the age-adjusted norm. We observed a significant improvement in RAVLT memory scores at 1 and 6 months postoperative compared with preoperative. We also observed significant improvement in multiple executive functions measures up to 12 months postoperative. The improvement on patients with preoperative stroke symptoms was less consistent. Conclusions: This prospective study showed that carotid intervention improved memory and executive function in patients with the severe carotid occlusive disease. It highlights the cognitive benefit of the carotid intervention in appropriately selected patients.

Introduction: Carotid occlusive disease is reported to impact cognitive function. Reduced cerebral blood flow is considered a culprit in carotid disease-related cognitive impairment. However, the association is not consistent. Aim: To investigate the relationship between baseline cerebral blood flow (BCBF) and cognitive functions in a well-defined cohort of patients with severe occlusive extracranial carotid disease. Methods: Patients undergoing carotid intervention for occlusive diseases were prospectively recruited from two academic institutions. All patients received neurocognitive testing and MRI scanning pre-intervention. For neurocognitive testing, raw scores were normalized against age, education, and standard scores as appropriate. The cognitive domain-specific normalized scores were derived using principal component analysis. Univariate and multiple linear regression models were fitted to evaluate predictors of various cognitive domains including memory, executive function and language. Variables with P<0.1 in the univariate analysis were included in the multiple models. Results: A total of 140 patients were included in our analysis. Most patients were males (96%) with a mean age of 69.9 years. Almost half of the cohort (50.8%) were symptomatic. Most patients were smokers (78.1%) and hypertensive (86.4%). Diabetes was prevalent (39.4%). In the multiple regression model, BCBF was independently associated with Trail Making Test (TMT) [regression coefficient(B)=-0.015, Standard Error (SE):0.008, p=0.04]. Other significant predictors of TMT were prior stroke and diabetes. BCBF was also associated with scores on the Stroop test (B=0.023, SE=0.009), albeit nonsignificant, in the multiple regression model (P=0.06). Age, renal insufficiency, and prior stroke were independently associated with Stroop test, p<0.5. Conclusion: Our study showed an association between BCBF and baseline executive function measured by TMT in patients with severe carotid occlusive disease. BCBF was also associated with Stroop test in a trend that did not reach statistical significance. Inconsistency in the association between CBF and cognitive function may be due to diverse cognitive measures and patient-related comorbidities.