July 1, 2008

Ten Percent May Have Had Silent Stroke

Ten percent of seemingly healthy middle-aged people have experienced silent stroke injury, U.S. researchers said.

Silent stroke is an interruption of blood flow in the brain known as silent cerebral infarction.

The study, published in Stroke: Journal of the American Heart Association, also reported a significant correlation between silent cerebral infarction and a form of heart arrhythmia common in people over 65 years old -- atrial fibrillation.

In our data, atrial fibrillation increased the risk of prevalent silent cerebral infarction more than two-fold, study co-author Dr. Sudha Seshadri of the Boston University School of Medicine said in a statement. The findings reinforce the need for early detection and treatment of cardiovascular risk factors in mid-life. This is especially true since silent cerebral infarction have been associated with an increased risk of incident stroke and cognitive impairment.

The researchers evaluated magnetic resonance imaging scans from about 2,000 people -- average age 62 -- taking part in the Framingham Offspring Study made up of the children of the participants in the original Framingham Heart Study.

The Framingham Heart Study, begun in 1971, was designed to identify the common factors that contribute to cardiovascular disease by tracking a large group of participants over a long period of time.