Transient ischemic attacks

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VOL 111 / NO 3 / MARCH 2002 / POSTGRADUATE MEDICINE

When the blood flow to part of the brain is temporarily reduced, that area of the brain doesn't work the way it is supposed to. The decreased blood flow causes a condition known as ischemia, which often triggers symptoms such as numbness, clouded vision, slurred speech, confusion, or dizziness.

A transient ischemic attack (TIA) is a temporary interruption in blood flow that is like a small stroke. The symptoms usually disappear completely within an hour or so but sometimes last as long as 24 hours. TIAs are important warning signs; about one third of people who have them go on to have more serious strokes later, particularly if other health risks are present.

What are the usual symptoms?
The warning signs of TIAs are the same as those for strokes. They include the following:

• Numbness or weakness of the face, arm, or leg on one side
• Difficulty seeing clearly
• Difficulty speaking or understanding others
• A headache that comes on suddenly
• Confusion, dizziness, and severe drowsiness
• Loss of coordination

Not all of these symptoms occur with every attack, and sometimes they go away and then return later. Nonetheless, if any of these symptoms occur, it is important to get help quickly. Also, if you notice one or more of these problems in another person, call 911 immediately or get that person to a hospital as soon as possible.

How are TIAs treated?
Every TIA should be considered a life-threatening emergency. Timing is very important because early treatment produces the best results. Your doctor will want to find the cause of the problem and then decide which treatment is best. An ultrasound examination of the arteries leading to the brain often is helpful. Computed tomographic (CT) scans and electrocardiographic (ECG) tests also provide important information. Blood tests can help predict risks and determine the severity of the problem. In many cases, treatment will involve getting blood pressure under control or lowering cholesterol and then making lifestyle changes.

Who is at risk?
A number of factors increase the risk of having a TIA or a full-blown stroke. These include:

• High blood pressure
• Cigarette smoking
• Regular and excessive use of alcohol
• Abnormal heart rhythm
• High blood cholesterol levels
• Diabetes
• Use of birth control pills, especially in women over age 35 who smoke
• Old age
• Obesity
• Sedentary lifestyle
• A family history of TIAs or stroke

All of these risk factors are important on their own, but they are especially important in people who have a TIA. Some of these risks can't be changed, but others can. Your doctor can help you stop smoking, lose weight, and keep blood pressure, cholesterol levels, and diabetes under control. Exercise can greatly reduce risks. However, be sure to check with your doctor before you start a vigorous exercise program.

When to call the doctor
Call your doctor right away if you notice any of the warning signs of TIA or stroke. This is especially important because serious strokes can occur without any previous warning signs. New treatments may prevent some problems if they are used within a few hours of the time when symptoms first occur.

Warning signs of TIAs

The signs and symptoms of transient ischemic attacks (TIAs) often come on suddenly. If one or more of the following occur, they should be considered a serious warning sign of decreased blood flow to the brain:

• Weakness or numbness, especially on one side of the face or body or in one arm or leg
• Trouble speaking clearly
• Loss or dimming of vision, especially in one eye
• Confusion
• Dizziness, unsteadiness, or loss of coordination
• A severe headache that occurs suddenly

If you have any of these signs, call 911 or have someone take you to a hospital immediately.

This information is not a substitute for medical treatment.

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