Understanding stroke: Risk factors and prevention

Risk factors increase your chance of having a stroke. If you get rid of or control them, your odds of having another stroke will go down.

The sooner you control your risk factors, the better off you will be. Your doctor can help you learn what your risk factors are and how you can control them. This may mean seeing your doctor more often.

Eight controllable risk factors

The National Stroke Association lists eight risk factors that you can control:

1. High blood pressure

This is the most important because there are usually no symptoms. Your blood pressure is high if it is usually equal to or higher than 130/90. High blood pressure puts stress on your blood vessel walls. This can lead to stroke from blood clots or bleeding.

Prevention: You should have your blood pressure checked every year. Check your blood pressure more often if you have or your family has a history of heart disease or high blood pressure.

2. Smoking

Tobacco use doubles your stroke risk. It damages blood vessel walls, speeds up clogging of your arteries, raises your blood pressure and makes your heart work harder.

Prevention: If you smoke, stop. After 5 years, your stroke risk is the same as someone who has never smoked. Your doctor can give you information about quitting smoking.

3. Heart disease

About 15 percent of all stroke survivors have a heart disorder called atrial fibrillation or irregular heartbeat. This causes the upper right chamber of your heart to beat quickly and out of rhythm. Blood pools in your heart and often forms clots. These clots travel to your brain through your bloodstream.

Prevention. Your doctor will talk with you about how to treat atrial fibrillation, as well as heart disease caused by the build-up of plaque in heart blood vessel walls.

4. High cholesterol

High cholesterol can put you at greater risk of heart disease and often speeds up the clogging of the arteries.

Prevention: Your doctor may put you on a low-fat diet and have you exercise. If this doesn't work, you may need to take medicine to lower high cholesterol.

5. Alcohol

Drinking too much alcohol is linked to strokes. It can raise your blood pressure.

Prevention: Do not drink excessively. Ask for help if necessary. (Our alcohol and drug inventory may help you decide.)

6. Weight

Carrying extra weight strains your circulatory system. Extra weight also makes you more likely to have other risk factors such as high cholesterol, high blood pressure and diabetes.

Prevention: Your doctor can talk with you about weight loss and exercise goals.

7. Carotid artery disease

Your carotid arteries carry blood to your brain. When plaque (a fatty substance) builds up in these neck arteries, you are at risk for an ischemic stroke.

Prevention: Your doctor may order a carotid ultrasound and other tests to determine how much plaque is present. Angioplasty or surgery to remove the plaque may help prevent strok in some cases. Sometimes, tubes (stents) are placed in the artery to help keep it open.

8. Birth control pills

Women who take birth control pills have a slightly increased chance for stroke. This chance may rise if there are other risk factors.

Seven uncontrollable risk factors

There are other risk factors you cannot control. These are part of your genetic makeup (who you are).

Prevention: Your doctor can test for potential risk factors. Some of them may be treated with medicine or lifestyle changes.

1. Race

Rates of stroke vary among races. The reasons are not known. Lifestyle and environment can have an effect. In the U.S., African-Americans have a higher rates of high blood pressure and stroke.

2. Family history (genetics)

A history of heart disease and brain vessel disease can be a stroke risk factor. By watching your diet, leading a healthful lifestyle and exercising, you may reduce your chances of stroke.

3. Diabetes

Diabetes (type 1 and type 2) increases the chance of stroke in both men and women. The link between diabetes and stroke seems to be related to the circulatory problems caused by diabetes. You can control diabetes, but you can't totally eliminate the stroke risk.

4. Transient ischemic attack (TIA) or stroke

If you have already had Transient ischemic attack (TIA, 'mini-stroke' ) or a stroke, you are at risk for having another.

5. Age

Your chance of having a stroke goes up with age. Two-thirds of strokes occur in people older than age 65.

6. Gender

Men have more strokes than women. Because women often live longer than men, many stroke survivors older than 65 are women.

7. Bleeding disorders

Some people have abnormal amounts of different proteins in their blood that can change the way blood clots and increase the risk of stroke. Certain diseases and medicines can also affect how blood clots.