African-Americans may be at higher risk of stroke-causing brain lesions

ST. PAUL, Minn. – Cerebral microbleeds, which are small bleeds within the brain, appear to be more common in African-Americans than in Caucasians, increasing the likelihood of having a stroke, according to a study published in the October 7, 2008, issue of Neurology®, the medical journal of the American Academy of Neurology. These types of brain lesions can be an important indicator for stroke.

For the study, 87 people from the Washington, DC, area who had suffered a certain type of stroke, called an intracerebral hemorrhage, underwent brain scans. This kind of stroke involves bleeding in the brain and makes up 10 to 15 percent of all strokes. Researchers also determined the group's risk factors for stroke such as age, hypertension and alcohol use. Forty-two of the people were African-American while 45 were Caucasian.

The study found that African-Americans had 32 percent more microbleeds than Caucasians. African-Americans were also more likely to have these types of lesions in several different areas of the brain. While African-Americans had more lesions in the lower and middle parts of the brain, Caucasians had them most frequently near the surface of the brain.

"Finding racial differences that could be linked with a higher prevalence for these brain lesions may lead to new methods for testing and treating people to prevent stroke," said study author Chelsea Kidwell, MD, with Georgetown University Medical Center in Washington, DC, and member of the American Academy of Neurology.

"Knowing if a person has a higher likelihood of having these brain lesions or bleeding in the brain is important for doctors and patients when caring for medically underserved groups of people and optimally treating their stroke risk factors," said Kidwell. Hemorrhagic stroke is two to three times more common in minority populations, including African-Americans. Microbleeds are found in 50 to 80 percent of this type of stroke.

Source: American Academy of Neurology