Carotid endarterectomy (CEA) is not associated with a significant reduction in the risk of dementia, according to a new analysis published in the European Journal of Vascular & Endovascular Surgery. However, the study’s authors noted, it did still lead to considerable improvements in stroke risk.
“Small, short-term, observational studies have suggested that CEA or stenting might improve cognition, but, because cognitive decline and dementia rates are not measured routinely in randomized trials or registries, there is no clear evidence of longer-term benefit or hazard,” wrote first author Alison Halliday, MD, an emeritus professor of vascular surgery at Oxford University’s Nuffield Department of Surgical Sciences, and colleagues.
Halliday et al. examined data from 1,601 patients with asymptomatic tight carotid stenosis. The mean patient age was 69 years old, 63.9% were men, 16.6% had a history of stroke and 15.6% had a history of diabetes. Also, 28.7% of patients had confirmed ischemic heart disease. While 796 patients underwent immediate CEA, and CEA was deferred for the remaining 805 patients.
The median follow-up period for patients was 19.4 years. Dementia was seen in 107 patients who underwent immediate CEA and another 115 patients who delayed surgery. A significant number of patients did die during follow-up, including more than 1,000 who died before any dementia diagnosis could be confirmed.
Dementia was more likely among female patients and patients with a history of cerebral infarction, the authors added. Also, the most common dementia diagnoses were vascular dementia (35.7%), Alzheimer’s disease (28.1%), “dementia of unspecified type” (27.6%), “possible dementia” (7.7%) and “rare dementia” (0.9%).
“Because stroke is closely associated with dementia risk, it remains possible that the prevention of stroke in specific high-risk populations may be beneficial in preventing dementia,” they wrote. “European guidelines will continue to consider whether particular groups of asymptomatic patients, such as those with prior symptoms, cerebral infarction, or impaired cerebrovascular reserve, might benefit from carotid intervention, but a large, long term randomized study will be necessary to determine this.”