Loss of Brain White Matter Increases Stroke Risk

Researchers have established that leukoaraiosis, changes in the brain's white matter that usually occur in the elderly, increases the risk of multiple strokes.

Investigators studied 685 patients aged 34 to 84 years with carotid artery disease who participated in the 2,885-patient North American Symptomatic Carotid Endarterectomy Trial (NASCET) and who had a follow-up computed tomography (CT) scan taken three years or more from entry in the study.

Of the 685 patients in the study, 596 had no leukoaraiosis and 89 had limited white matter. During an average follow-up of 6.1 years, 18% of the 596 patients initially free of leukoaraiosis developed some loss of white matter and 3% had widespread loss. The average age of patients who developed leukoaraiosis was 66.8 years.

The group of patients who developed leukoaraiosis showed a higher tendency to experience at least one stroke: 36% versus 23.5% for the group without leukoaraiosis. After taking gender, age, smoking history, and diseases such as hypertension and diabetes mellitus into consideration, results showed that the patients who developed leukoaraiosis were 1.5 times more likely to have a stroke. The findings were published July 17, 2003, in the online edition of Stroke.

"Patients who developed leukoaraiosis were more likely to have multiple strokes, which generally lead to increased disability, both physically and mentally,” said first author Dr. Jonathan Y. Streifler, director of the neurology unit at the Rabin Medical Center (Petach Tikva, Israel). "These small strokes can be devastating when they hit strategic connections.”