Stroke 101What is a Stroke and Why Does it Occur?
A stroke occurs when the blood supply to part of the brain is suddenly interrupted or when a blood vessel in the brain bursts, spilling blood into the spaces surrounding brain cells. Brain cells die when they no longer receive oxygen and nutrients from the blood or there is sudden bleeding into or around the brain.
There are two kinds of stroke. The most common kind of stroke, called ischemic stroke, is caused by a blood clot that blocks or plugs a blood vessel in the brain. The other kind of stroke, called hemorrhagic stroke, is caused by a blood vessel that breaks and bleeds into the brain.
What Are the Risk Factors?
A risk factor is a condition or behavior that occurs more frequently in those who have, or are at greater risk of getting, a disease than in those who don't. Having a risk factor for stroke doesn't mean you'll have a stroke. On the other hand, not having a risk factor doesn't mean you'll avoid a stroke. But your risk of stroke grows as the number and severity of risk factors increases.
Stroke occurs in all age groups, in both sexes, and in all races in every country. It can even occur before birth, when the fetus is still in the womb. In African Americans, stroke is more common and more deadly--even in young and middle-aged adults--than for any ethnic or other racial group in the United States. Scientists have found more and more severe risk factors in some minority groups and continue to look for patterns of stroke in these groups
Stroke prevention is still the best medicine. The most important treatable conditions linked to stroke are:
- High Blood Pressure. Treat it. Eat a balanced diet, maintain a healthy weight, and exercise to reduce blood pressure. Drugs are also available.
- Cigarette Smoking. Quit. Medical help is available to help quit.
- Heart Disease. Manage it. Your doctor can treat your heart disease and may prescribe medication to help prevent the formation of clots. If you are over 50, scientists believe you and your doctor should make a decision about aspirin therapy.
- Diabetes. Control it. Treatment can delay complications that increase the risk of stroke.
- Transient Ischemic Attacks (TIAs). Seek help. TIAs are small strokes that last only for a few minutes or hours. They should never be ignored and can be treated with drugs or surgery.
- Physical Inactivity. Just Move. Activities such as brisk walking, riding a bicycle, swimming, and yard work lower the risk of both stroke and heart disease. Researchers think that exercise may make the heart stronger and improve blood flow. Before you start a vigorous exercise program, be sure to check with your doctor.
- Poor Diet. Eat healthy foods. Eat foods that are low in fats, cholesterol, and saturated fatty acids. Include a variety of fruits and vegetables in your daily diet.
- High Cholesterol. Have power over it. High cholesterol in the blood (240 mg/dL or higher) is a major risk factor for heart disease and raises your risk of stroke.
- Certain blood disorders. Inquire. A high red blood cell count thickens the blood and makes clots more likely. This raises the risk of stroke. Doctors may treat this problem by removing blood cells or prescribing "blood thinners." Sickle cell disease (also called sickle cell anemia) is a genetic disorder that mainly affects African Americans. "Sickled" red blood cells are less able to carry oxygen to the body's tissues and organs. They also tend to stick to blood vessel walls, which can block arteries to the brain and cause a stroke.*
- Alcohol Abuse. Limit it. Drinking an average of more than one alcoholic drink a day for women or more than two drinks a day for men can raise blood pressure and may increase risk for stroke.*
- Illegal drugs. Don’t use them. Intravenous drug abuse carries a high risk of stroke. Cocaine use has been linked to strokes and heart attacks. Some have been fatal even in first-time users.*
- Age. People of all ages, including children, have strokes. But the older you are, the greater your risk for stroke.*
- Gender. Stroke is more common in men than in women. In most age groups, more men than women will have a stroke in a given year. However, women account for more than half of all stroke deaths. Women who are pregnant have a higher stroke risk. So do women taking birth control pills who also smoke or have high blood pressure or other risk factors.*
- Family history and race. Your stroke risk is greater if a parent, grandparent, sister or brother has had a stroke. African Americans have a much higher risk of death from a stroke than Caucasians do. This is partly because blacks have higher risks of high blood pressure, diabetes and obesity.*
- Previous stroke or heart attack. Someone who has had a stroke is at much higher risk of having another one. If you've had a heart attack, you're at higher risk of having a stroke, too. *
General Signs and Symptoms of Stroke
The symptoms of a stroke include sudden numbness or weakness, especially on one side of the body; sudden confusion or trouble speaking or understanding speech; sudden trouble seeing in one or both eyes; sudden trouble with walking, dizziness, or loss of balance or coordination; or sudden severe headache with no known cause.
How is a Stroke Treated
Generally there are three treatment stages for stroke: prevention, therapy immediately after the stroke, and post-stroke rehabilitation. Therapies to prevent a first or recurrent stroke are based on treating an individual's underlying risk factors.
Acute stroke therapies try to stop a stroke while it is happening by quickly dissolving the blood clot causing an ischemic stroke or by stopping the bleeding of a hemorrhagic stroke.
Post-stroke rehabilitation helps individuals overcome disabilities that result from stroke damage. Medication or drug therapy is the most common treatment for stroke. The most popular classes of drugs used to prevent or treat stroke are antithrombotics (antiplatelet agents and anticoagulants) and thrombolytics.
For more information about stroke:
American Stroke Association (http://www.strokeassociation.org)
National Stroke Association (http://www.stroke.org )
CDC's Cardiovascular Health Program (http://www.cdc.gov/cvh )
American Heart Association (http://www.americanheart.org)
Last Modified: 07/08/2008 11:12:00 AM