Someone suffers a stroke every 45 seconds in the U.S. The timing of this debilitating 'brain attack' may seem completely arbitrary, but according to the National Stroke Association , 80 percent of strokes are preventable.

Stroke is the third leading cause of death in the U.S. Of the approximately 750,000 Americans who will have a stroke this year, 150,000 will die. Although many women are keenly aware of their breast cancer risk, twice as many women will die of a stroke than breast cancer each year.

Many of the factors for stroke are the same for the number one killer in the U.S. — heart disease . Many of these determinants are controllable, such as diet, smoking and Type 2 diabetes. Even just one risk factor is enough to speak to a physician to learn what can be done to avoid these often debilitating, and sometimes fatal, attacks.

Understanding Strokes

During a stroke blood and oxygen are cut off to the brain cells that control all aspects of the body's functions — from speaking to walking and breathing.

The majority of strokes, 83 percent, are known as ischemic strokes. They occur when blood clots or plaque and other fatty deposits block arteries to the brain. The smaller percentage of strokes are hemorrhagic, or bleeding strokes, which are caused by arteries rupturing when weak spots on the blood vessel wall break.

Finally, there are transient ischemic attacks (TIA), often called mini strokes, which present blood — clotting conditions akin to ischemic strokes. However, since blood circulation is restored quickly after the TIA, the stroke symptoms disappear.

A TIA is often a strong indicator of future stroke risk. "You have to be aggressive in finding a cause of a TIA because the recurrence rate over a five — year period is between 35 to 40 percent," said Dr. Jesse Weinberger, director of the neurovascular laboratory at Mt. Sinai Hospital in New York City.

Controllable Risk Factors

High Blood Pressure (Hypertension) — High blood pressure affects about 65 million Americans, and is the biggest risk factor for stroke, Weinberger said. Hypertension increases stroke risk four to six times, but Weinberger said when blood pressure is adequately controlled, that risk is cut in half. Weinberger recommends having your blood pressure checked at least once a year by your primary care physician, and more often if you are above age 50 or have a history of high blood pressure.

Diabetes — Weinberger considers diabetes to be the second highest risk factor. The American Stroke Association notes that Type 1 and Type 2 diabetes increases stoke factor two to four times. Diabetics are particularly vulnerable to stroke because they often have other health problems such as high blood pressure, high cholesterol and are overweight, which compound stroke risk. Controlling diabetes through a physician prescribed nutrition program along with medicine and lifestyle changes is critical to reducing stroke risk.

High Cholesterol — High levels of cholesterol in the bloodstream can clog arteries, thereby causing a stroke. It can also increase stroke risk by putting someone at a greater risk for heart disease – another important stroke risk factor. According to the National Stroke Association, more than 100 million American adults have combined cholesterol levels over the recommended 200 mg/dL.

Atrial Fibrillation (AF) — Atrial fibrillation, sometimes referred to as an irregular heartbeat, raises stroke risk by allowing blood to pool in the heart. When the blood pools, it can form clots which can then be carried to the brain, causing a stroke. Any primary care physician can check a pulse for atrial fibrillation.

Circulation Problems — Poor circulation is often due to clogged arteries. Again, any primary care physician can check for bad circulation. Fatty deposits can block the arteries that carry blood from your heart to your brain causing a stroke.

Smoking — Smoking doubles stroke risk. Women smokers are especially vulnerable. If a woman smokes, has a history of migraines, and takes oral contraceptives, the National Stroke Association estimates her stroke risk is increased 34 times.

Excess Weight — While Weinberger says being overweight isn't automatically a culprit in bringing on a stroke, overweight people often present other factors, such as Type 2 diabetes and elevated cholesterol which together are strong risk factors. Preventing stroke is a lot like preventing heart disease, where good nutrition and exercise are key factors in reducing risk. Reducing sodium and fat in your diet is one easy way to possibly lower blood pressure and keep your weight in check, and hence, decrease stroke risk.

Excessive Alcohol Use — Some studies show drinking in moderation, such as having one glass of wine each day, may lower your risk for stroke, but other studies have linked excessive drinking to higher risk for stroke. These studies have shown that knocking back more than two drinks per day may increase stroke risk by 50 percent.

Uncontrollable Risk Factors

Age — According to Weinberger, a person's age plays a role in monitoring stroke risk. The older a person is, the more vulnerable he or she is to the possibility of a stroke. Weinberger adds that for women, the risk definitely increases with the onset of menopause. "Once people get into their 80s, the age risk factor between genders is equal," he said.

Gender — The incidence of stroke is higher in men than in women in all age classes, and women are, on average, several years older than men when they suffer their first stroke. Although men get strokes more often, the National Institute of Health reports that the majority of studies indicate the fatality rate is higher in female than in male stroke patients. There is also some evidence, suggesting that men have a better functional outcome. Post-menopausal women with a waist size larger than 35.2 inches and a triglyceride level higher than 128 milligrams per liter may have a five — fold increased risk for stroke.

Race — African Americans have a much higher stroke risk than Caucasians. Additionally, a study published last September by the U.S. Centers for Disease Control and Prevention showed black survivors fare worse than their Caucasian counterparts in function and control. The higher incidence of stroke in the African American population is due to the fact that their rate of hypertension is among the highest in the world, and they have higher incidences of obesity and diabetes.

Previous Stroke or TIA — Again, if you have already had a stroke or a TIA, you have a 35 to 40 percent chance of having another stroke, including a full-blown stroke, not another TIA, in the next five years. "It's critical to have a full workup to assess what caused the stroke, to assess the source of blockage to the brain," Weinberger said. The types of diagnostic procedures that would be typically used include a carotid artery ultrasound, a Magnetic Resonance Angiography (MRA) of the blood vessels and head and a transcranial Doppler to measure the blood flow in the brain.

Weinberger advised the best combat to these factors is to control the ones you can. "Controlling hypertension is first and the most important, then, in equal measure, controlling diabetes, high cholesterol and quitting smoking," he said. "Then finally, it's important to make lifestyle changes, such as proper diet and exercise to be vigilant."

How Can I Treat These Factors?

Weinberger believes the first line in isolating stroke risk factors should come from a person's internist or primary care physician. In addition to routinely checking a patient's pulse and blood pressure, an internist can examine for blockages in the carotid artery through a Doppler study. As an initial line of treatment, an internist will often treat patients at high risk of stroke with antiaggregant or platelet treating drugs.

If stroke risk factors are identified, the patient is usually advised to see one of both of the following types of doctors: a vascular neurologist (a boarded subspecialty of neurology) and/or a cardiologist. If a person has a TIA or mini stroke, that person should go directly to a neurologist because a TIA is considered a medical emergency, which warrants a thorough assessment of the TIA's cause so to prevent recurrence or a major stroke later.

For More Information:

National Stroke Association: http://www.stroke.org

American Stroke Association (a division of the American Heart Association): http://www.strokeassociation.org

NIH Senior Health: http://nihseniorhealth.gov/stroke/toc.html

Internet Stroke Center: http://www.strokecenter.org/prof/

This article was reviewed by Dr. Manny Alvarez.