A build-up of plaque in the carotid artery above the neck was associated with an increased risk of stroke for older white patients in a study by Daniel Bos, M.D., Ph.D., of the Erasmus Medical Center, Rotterdam, the Netherlands, and colleagues.

Stroke is common and a common cause of disability in people around the world. Atherosclerosis (plaque build-up in the arteries) of blood vessels inside the skull is considered one of the most important risk factors for stroke but that information is based on studies of people of Asian and African origin, who are most often affected by strokes worldwide, according to the study background.

The authors studied 2,323 white patients (average age, 69.5 years) who underwent computed tomography (CT) scanning to quantify the volume of intracranial carotid artery calcification (ICAC), a marker of intracranial atherosclerosis, between 2003 and 2006. The patients were monitored for strokes until 2012.

During follow-up, 91 patients had a stroke: 74 were ischemic (interrupted blood flow), 10 were due to bleeding and seven were unspecified. Larger ICAC volume was associated with higher stroke risk, independent of other stroke risk factors, such as carotid plaque score and calcification in other blood vessels.

"The findings of our study suggest that intracranial atherosclerosis is a major risk factor for stroke in the general white population," the authors conclude.