Understanding a Stroke
Stroke occurs when a blood vessel bringing blood and oxygen to the brain gets blocked or ruptures. When this happens, brain cells don’t get the blood that they need. Deprived of oxygen, nerve cells stop working and die within minutes. Then, the part of the body they control can’t function either. The effects of stroke may be permanent depending on how many cells are lost, where they are in the brain, and other factors.
87% of strokes occur when blood vessels to the brain become narrowed or clogged with fatty deposits called plaque, cutting off blood flow to brain cells. A stroke caused by lack of blood reaching part of the brain is called an ischemic stroke. High blood pressure is the most important risk factor for ischemic stroke that you can change.
About 13 percent of strokes happen when a blood vessel ruptures in or near the brain. This is called a hemorrhagic stroke and when a hemorrhagic stroke happens, blood collects in the brain tissue. This is toxic for the brain tissue causing the cells in that area to weaken and die.
What is a TIA?
TIA, or transient ischemic attack, is a “minor stroke” that occurs when a blood clot blocks an artery for a short time. The symptoms of a TIA are the same as those of a stroke, but they usually last only a few minutes. About 15 percent of major strokes are preceded by TIAs, so don’t ignore a TIA. Call 9-1-1 or seek emergency medical attention immediately!
Isn’t stroke hopeless?
No. Stroke is largely preventable. You can reduce your stroke risk by living a healthy lifestyle — controlling high blood pressure; not smoking; eating a low-fat, low-cholesterol diet; being physically active; maintaining a healthy body weight; managing diabetes; drinking moderately or not at all. Also, much is being done to fight the effects of stroke. For example, the FDA approved use of the clot dissolving drug tissue plasminogen activator (tPA) to treat stroke. This is an advance because tPA can stop a stroke in progress and reduce disability. But to be eligible for tPA, you must seek emergency treatment right away, because it must be given within 4.5 hours after symptoms start, and have a clot-caused stroke.
What are the risk factors I can't control?
- Increasing age. Stroke affects people of all ages. But the older you are, the greater your stroke risk.
- Gender. In most age groups, more men than women have stroke, but more women die from stroke.
- Heredity and race. People whose close blood relations have had a stroke have a higher risk of stroke. African Americans have a higher risk of death and disability from stroke than whites, because they have high blood pressure more often. Hispanic Americans are also at higher risk of stroke.
- Prior stroke. Someone who has had a stroke is at higher risk of having another one.