Stroke : Controlling High Blood Pressure, Reducing Risk Factors

by Food and Drug Administration (FDA)

(Page 3 of 3)

Controlling High Blood Pressure

Because high blood pressure is responsible for about 70 percent of hemorrhagic strokes, controlling blood pressure is the most effective way to prevent this type of stroke, as well as strokes due to blockages. If President Roosevelt's physicians had had the kind of blood pressure-lowering drugs available today, FDR probably would have lived at least long enough to share victory in the second World War.

Included among today's more commonly prescribed medications to treat hypertension are diuretics that stimulate urination, thus reducing blood volume and blood pressure by eliminating excess fluid and sodium; beta blockers that lessen the heart's work by slowing heart rate and output of blood; calcium channel blockers that relax and dilate blood vessels by preventing calcium from entering into body cells; and ACE (angiotensin- converting enzyme) inhibitors that block the release of a kidney hormone that causes blood vessels to narrow.

Individuals who have had a stroke from subarachnoid hemorrhage due to a ruptured aneurysm may have another complication a week or so later when an artery near the injured area constricts, or goes into spasm, cutting off the blood supply and causing a second stroke. Nimotop (nimodipine), a calcium channel blocker approved in 1988, decreases the chance of another stroke by preventing spasm and may reduce the severity of stroke- related disabilities.

In cases where it seems that narrowed carotid arteries in the neck are causing or will cause strokes, a procedure called carotid endarterectomy may be recommended. Surgeons remove the atherosclerotic plaque that is clogging the carotid artery by opening up the artery, scraping out the plaque, and sewing the artery together again.

The North American Symptomatic Carotid Endarterectomy Study, published in Stroke (June 1991), showed that the operation reduced the risk of a major or fatal stroke in patients with carotid artery blockages of 70 percent or greater who had had recent TIAs or a mild stroke. Studies are ongoing to find out whether the operation will benefit symptomatic patients with less than 70 percent narrowing and those who have significant clogging and no symptoms.

Most people who have had mild strokes, and about half of those who have had moderate or severe paralysis on one side, recover enough to walk out of the hospital under their own steam or with some mechanical aid and resume their lives, though with certain limitations. But others are not so lucky. Many of the survivors face a bleak future, with disabilities that require special services or lifelong institutional care. People with one or more risk factors for stroke (see accompanying article) should do everything they can to avoid the consequences of this devastating disease.

Reducing Risk Factors

Though more common in the elderly, stroke may occur at any age. The American Heart Association reports that more than 1 in 7 who die from stroke are under 65. Reducing risk factors can help prevent stroke. These risk factors include:

High blood pressure. The force of blood beating with great pressure against artery walls weakens the walls and promotes the buildup of atherosclerotic plaque.

Elevated blood cholesterol. Clots that can travel to the brain don't usually form in normal hearts, but they may form in heart disease and after a heart attack and heart surgery. Reducing high blood levels of LDL-cholesterol — the so-called "bad" type — and increasing levels of HDL-cholesterol may retard the formation of atherosclerotic plaque. (See "Lowering Cholesterol" in the March 1994 FDA Consumer.) A low-fat, low- cholesterol diet benefits not only the coronary arteries, but arteries throughout the body, including those supplying blood to the brain.

Cigarette smoking. Many studies have shown a relationship between smoking and strokes. If you smoke, try to stop.

Heavy alcohol consumption. Chronic alcoholism and very heavy drinking are risk factors for both thromboembolic and hemorrhagic stroke, as well as increased mortality from stroke. Some studies show that moderate alcohol consumption may protect against cerebrovascular disease by raising HDL levels and helping prevent excessive blood clotting. But alcohol consumption should be limited to no more that one or two drinks a day, a drink being defined as 12 ounces of beer, 4 ounces of wine, or 1.5 ounces of 80-proof spirits.

Diabetes. People with diabetes — especially women — have almost double the risk of stroke. Diabetes causes atherosclerosis earlier in life and of greater severity. Besides damaging blood vessels, diabetes appears to interfere with the normal breakdown of fibrin, a plasma protein that holds blood clots together.

TIAs. If you have any evidence of a TIA — a sudden buckling of one leg leading to a fall, temporary blindness in one eye, slurred speech — tell your doctor immediately.

Family history. If a parent or sibling has had a stroke or TIA, you may also be at increased risk. It's not known whether this increased risk is inherited or from unhealthy family lifestyles.

Men have a higher stroke risk than women, and blacks have a higher stroke risk than people of other races.

Since age, gender, heredity, and race can't be changed, it's wise to work on the stroke risk factors that can be altered, such as high blood pressure, high cholesterol levels, cigarette smoking, and heavy alcohol consumption.

About the Author

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