Columbia-Led Study Finds Carotid Artery Procedures Do Not Improve Cognition

Severe narrowing of the carotid arteries, which supply blood to the brain, has been linked to cognitive impairment even in patients who have not experienced a stroke. But can restoring blood flow through stenting or surgery improve cognition?

A new study published in JAMA, led by Randolph S. Marshall, MD, the Elisabeth K. Harris Professor of Neurology and chief of the Division of Stroke and Cerebrovascular Disease at Columbia University Vagelos College of Physicians and Surgeons, suggests otherwise.

The study, known as CREST-H, was a substudy of the larger, multicenter CREST-2 randomized clinical trial, which investigated treatments to prevent stroke in patients with severe carotid artery narrowing but no recent stroke. CREST-H specifically examined whether restoring blood flow through stenting or surgery could improve cognitive function. Among 291 participants evaluated, researchers found no significant cognitive benefit from these procedures compared with intensive medical management alone after one year.

“We had hoped that improving blood flow in the brain in this way would improve cognition—and there were tantalizing clues from animal studies and case series that it would,” said Dr. Marshall. “But when we put it to the test in a randomized clinical trial, comparing cognition after opening the blockage or treatment with medication alone, we did not see a difference.”

The findings challenge the assumption that improving blood flow through narrowed carotid arteries can reverse cognitive impairment. While carotid interventions may offer benefits for stroke prevention, the CREST-H results do not support their use specifically to improve cognition.

Read the full story in the CUIMC Newsroom.