What is a stroke?
It is a loss of blood supply to a part of the brain, due to a blood clot in an artery within the brain or to bleeding within the brain, often leading to a chronic disability. A disability is defined by the World Health Organization as “any restriction or lack of ability to perform an activity in a manner or within the range considered normal for a human being.”
Types of Stroke.
All strokes are either hemorrhagic (15%) or ischemic (85%). Hemorrhagic ones are caused by sudden bleeding within the brain tissue (when an artery bursts), whereas ischemic ones occur when an artery is blocked by a clot which either forms in the artery or comes from the heart or a larger artery in the neck. The severity of the stroke depends on which part of the brain is affected and how big the artery blocked is: the bigger the artery, the bigger the area of brain it supplies, and therefore the greater the loss of function. Thus, you can have only a mild weakness and loss of coordination in one hand, which gradually resolves over months; or, no movement at all of the complete side of your body, including the loss of vision on that side and sometimes the loss of speech and swallowing.
What is the risk of another Stroke?
It has been estimated that, out of 100 people, four to twelve will have another stroke or mini-stroke within a week and 11 to 15 within a month, depending on the number of risk factors; the more risk factors, the greater the risk. For example, if a person has diabetes, is over age 60, has obvious weakness, and slurring of speech, then the risk of another stroke occurring within 90 days is 34% – meaning one in three people will have another one. Stroke has a five year survival of 30 to 50%; meaning up to half the people who have one will die within five years.
Can another one be prevented?
The more you can reduce risk factors, the greater the chance you have of avoiding another stroke. The risk factors you can modify are high blood pressure, high cholesterol, diabetes, and smoking. For those few people whose stroke is due to thickening of their carotid arteries (the arteries in the neck supplying blood to the brain), surgery can sometimes help.
How is it treated?
Treatment is divided into the “Acute” phase and the “Chronic” phase.
ACUTE Brain Attack:
Many people have heard of stroke victims being given anti-coagulants (thrombolytics or “clot busters”) at the onset of the stroke, similar to what heart attack victims receive. This procedure requires a strict protocol: the “clot buster” must be administered within three hours from the time of the first symptoms. If the symptoms are mild, or if you are beginning to improve, or if your blood pressure is too high, it should not be given. It remains a risky procedure even when done in a hospital which does it frequently. For now, the most important initial therapy is to take aspirin and to begin physical therapy as soon as possible.
1. Drugs: Aspirin (ASA) remains the drug of choice. It reduces the clumping of the platelet blood cells which caused the clot and reduces the risk of a second stroke. Plavix [clopidogrel] has a similar action as aspirin and is used when someone was already on aspirin when the stroke occurred or cannot take aspirin. (see handout Clopidogrel (Plavix): when should seniors take it?) There is no evidence that treating an acute stroke with other “blood thinners” has any benefit in reducing the risk of another one – except if a person has atrial fibrillation (an irregular heart rhythm) in which case warfarin (Coumadin) sometimes helps. (see the handout Warfarin (Coumadin): when should seniors take it) Antidepressants – there is now good evidence that stroke patients who receive an antidepressant have a better recovery.
2. Rehabilitation: Initiating physical, occupational, and speech therapy as soon as possible, improves recovery. Therapists work daily strengthening muscles and teaching techniques which help a person manage their situation.
What are the chances of recovery?
The first question everyone asks is “What are my chances of being disabled?” In general, a patient will more likely have some permanent disability when several of the following factors are present three days after the onset of the stroke:
1. age over 75
2. either arm paralyzed
4. fever over 38C
6.reduced level of consciousness
8. trouble swallowing
9. difficulty sitting
10. history of a previous stroke
11. having a neurological complication such as a seizure or hemorrhage into the brain
The more factors a patient has, the more likely she will be dependent on others three months later (30-60 per 100 will be dependent or dead).
Everyone is different and some improve much better than expected. But, it is helpful to know what to expect so that one can plan for various possibilities – “Hope for the best, but be prepared for the worst!”
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