Carotid endarterectomy protects elderly patients from cognitive decline: a prospective study

Background: Carotid endarterectomy (CEA) reduces the risk of stroke in selected patients with symptomatic and asymptomatic carotid disease, but its beneficial influence on cognitive performance in the elderly remains debatable. This prospective study sought to determine early and long-term neurocognitive outcomes after CEA for severe unilateral carotid artery stenosis.

Methods: From July 2006 to December 2008, 75 symptomatic (group A) and 70 asymptomatic patients (group B) aged 65 years and older underwent CEA under general anesthesia. Sixty-eight age- and sex-matched individuals who underwent laparoscopic cholecystectomy during the same period at our institution served as a control group (group H). Patients with contralateral severe carotid stenosis or occlusion and those with dementia, depression, or a history of major stroke were excluded. Cognitive function was assessed using 2 neuropsychological tests (the Mini-Mental State Examination [MMSE] and the Montreal Cognitive Assessment [MoCA]) performed preoperatively (T0) and then 3 (T1) and 12 months (T2) after operation. A change of at least 2 points between the scores at T0 and T2 was arbitrarily considered as clinically significant.

Results: At T0, group A revealed significant cognitive impairments in both mean test scores by comparison with group H (P = .005 and P < .01, respectively), whereas there were no significant differences between groups A and B, or between groups B and H. Postoperatively, symptomatic patients had significant improvements in their mean cognitive performance scores in both tests (P < .01 and P < .01, respectively), whereas there were no changes in the asymptomatic and control patients' scores. No significant differences emerged for the MMSE scores in the 3 groups, whereas there was a marginally significant difference in the MoCA scores between groups A and H (P = .08), but not for A versus B or B versus H when clinically significant scores were considered.

Conclusion: Our study showed that only elderly symptomatic patients with severe carotid lesions had a significant improvement in cognitive performance scores after CEA, although the benefit was considered clinically not significant. This suggests that CEA does not diminish neurocognitive functions, but it might provide some protection against cognitive decline in the elderly.