Stroke is the most common cause of adult disability and ranks fourth as the leading killer of adults in the US. A stroke occurs when blood circulation to the brain fails. When there is decreased blood flow and hence oxygen getting to the brain, the affected brain cells can die. The most frequent cause of stroke, occurring about 80% of the time, is the ischemic stroke, resulting from a blockage of a blood vessel in the brain or neck.
Warning signs of a stroke are clues that your brain is getting insufficient oxygen and you should call 911 right away. These warning signs can include: (1) sudden numbness or weakness involving your arm, leg, and/or face, (2) sudden difficulty with balance, walking, or coordination (3) sudden dizziness, (4) sudden severe headache for no reason, (5) sudden difficulty seeing or sudden double vision, (6) sudden drowsiness for no reason, and (7) sudden difficulty speaking or understanding speech. These symptoms can sometimes only last minutes or hours (known as transient ischemic attacks or TIAs) but it is still an indicator of a serious condition and you should call 911 immediately.
Controlling certain risk factors and knowing the warning signs of stroke can help lower your risk of death or disability from stroke.
A risk factor is a condition or behavior that occurs more frequently in those who have, or are at greatest risk of getting, a disease than in those who don’t. Having a risk factor does not mean that you will have a stroke or that not having a risk factor means that you will avoid a stroke. Some risk factors can be modified and others cannot.
Modifiable risk factors for stroke include: (1) hypertension (high blood pressure), (2) cigarette smoking, (3) heart disease (such as coronary artery disease, heart valve defects, atrial fibrillation, and cardiac enlargement), (4) history of TIA or stroke, (5) diabetes mellitus, (6) cholesterol imbalance, and (7) physical inactivity/obesity. Of these, hypertension is the most potent risk factor.
Non-modifiable risk factors include: (1) advanced age (doubling for each decade between 55 and 85), (2) male sex, (3) African-American or Hispanic American ethnicity, and (4) family history of stroke.
Although the risk for stroke is never zero, the earlier you improve upon your modifiable risks the lower your risk of death or disability from stroke. The National Institute of Neurological Disorders and Stroke (NINDS), a component of the NIH, using data from the Framingham Study, have published stroke risk score tables. If you are 55 or older, you should see your physician to determine your risk factors and calculated stroke risk.
For more information, call the Institute’s information network at 1-800-352-9424 or look them up on the web at www.ninds.nih.gov.