Way to Predict Stroke after 'Mini-Stroke' Found

Speech disturbance and weakness on one side are the primary predictors, study finds

WEDNESDAY, June 22, 2005 (HealthDay News) -- A mini-stroke can signal the impending possibility of a full-blown stroke, but many are missed or not taken seriously by doctors and patients alike.

Now there is a simple risk score that doctors can use to predict whether a patient is likely to have a stroke in the week following a mini-stroke, or transient ischemic attack (TIA), British researchers report in the June 21 online issue of The Lancet.

A TIA occurs when a blood clot blocks an artery in the brain for a short time. The symptoms of a TIA are similar to the warning signs of a stroke, but they usually last only a few minutes.

According to the American Stroke Association, signs of a TIA can include all or some of the following: sudden numbness or weakness of the face, arm or leg, especially on one side of the body; sudden confusion; trouble speaking or understanding; sudden trouble seeing in one or both eyes; sudden trouble walking, dizziness, loss of balance or coordination; and sudden severe headache with no known cause.

"We looked at the characteristics of the event in patients who had a TIA, and predicted the risk of a major stroke within the next seven days," said study author Dr. Peter Rothwell, a professor of clinical neurology at the University of Oxford.

By studying 200 patients who had a TIA, Rothwell and his colleagues developed the simple score, which is based on age, blood pressure, clinical features and duration of symptoms.

The researchers tested the risk score in two separate groups of similar patients, and found they could predict the risk of stroke during the first seven days after TIA.

"People with a low score had no early recurrent stroke," Rothwell said. "People with the highest score had a risk of about 30 percent." The score is not a perfect predictor of stroke, but it can steer doctors to those patients whose risk for stroke is very high.

The main predictors of an early stroke are speech disturbance and weakness in one side of the body that lasts more than 10 minutes, Rothwell said.

Rothwell believes doctors can use the score to identify patients at a very high risk of having a stroke within a few days. "It can also be used to focus public education about TIA," he said.

One expert thinks the study is valuable. "I like this paper because it emphasizes how high the risk really is for a stroke after a TIA," said Dr. Lawrence M. Brass, a professor of neurology and epidemiology and public health at the Yale University School of Medicine.

In addition, using their simple score is a way to really identify the patients who are at high risk for a stroke after having had a TIA. "As much as I'd like everybody to be seen by a specialist within 12 hours of having their spell, it's not often practical," Brass said. "For me, this result is going to make me figure out the people who had better be seen tomorrow."

Brass believes TIAs should never be taken lightly. "TIAs are a really bad disease," he said. "Often patients will ignore them. These results, which show the very high risk of early recurrence, should prompt patients to get into the emergency room when they have these spells, even if they have gotten better, because the risk of having a stroke can be very high."

Moreover, "TIAs represent a window of opportunity for us to intervene to prevent a stroke," Brass said. "No TIA should be ignored, but there are some that require special urgency, with more aggressive therapy."

Brass also said that patients should ask their doctor about their risk of having a stroke, and what they and their doctor can do to reduce that risk. "The more patients become active partners in preventing stroke, the better it is for both the patient and the physician."

More information

The American Stroke Association can tell you more about stroke.

SOURCES: Peter Rothwell, M.D., professor, clinical neurology, University of Oxford, England; Lawrence M. Brass, M.D., professor, neurology and epidemiology and public health, Yale University School of Medicine, New Haven, Conn.; June 21, 2005, The Lancet online
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