Director of the Evelyn F. McKnight Brain Institute at the University of Alabama at Birmingham and Colleagues found that Restoring Blood Flow Does Not Improve Cognition in Patients with Asymptomatic Carotid Artery Stenosis
A recent study led by Ronald M. Lazar, PhD, Director of the Evelyn F. McKnight Brain Institute at the University of Alabama at Birmingham, found that while patients with severe narrowing of the carotid arteries often experience subtle cognitive deficits, restoring blood flow through surgical or minimally invasive procedures does not improve cognitive performance.
The study findings “Revascularization of Asymptomatic Carotid Artery Stenosis: Cognitive Results of the CREST-2 Randomized Trials,” were published recently by JAMA and are based on the cognitive study embedded in the CREST-2 trial, which represents the largest randomized investigation to date examining whether carotid revascularization will improve thinking and memory in patients with asymptomatic carotid artery stenosis.
Previous work by Dr. Lazar and colleagues found that patients with severe asymptomatic carotid artery stenosis performed below expectations on cognitive testing without history of stroke or other neurological symptoms. This study aimed to build on that work and determine if the cognitive deficits caused by reduced blood flow to the brain from a chronic blockage in the carotid artery could be reversed by restoring circulation.
Researchers followed more than 2,100 participants enrolled in the CREST-2 trial who were randomized to receive either intensive medical management alone or combined with carotid revascularization through carotid endarterectomy or carotid artery stenting. The participants were followed for up to four years and their performance was assessed across multiple cognitive domains, including memory, attention, executive functions and processing speed.
While blood flow was successfully restored in the treated patients, the study found no significant cognitive improvements for either carotid endarterectomy or carotid artery stenting compared with intensive medical management alone.
“Our study results suggest the relationship between carotid artery disease and cognition is likely more complex than restoring blood flow alone,” Dr. Lazar said. The emerging data provide further support that preventing cardiovascular disease by managing risk factors and making lifestyle modifications, like not smoking, reducing high blood pressure, following a healthy diet and exercising regularly are among the best ways to avoid carotid stenosis.”