What are the risk factors for a stroke?
High blood pressure (hypertension) does not cause any symptoms, so everyone over the age of 40 should have an annual blood pressure check. High blood pressure has no warning signs, so regular blood pressure checks are important. The
condition can be easily and successfully controlled with medication.
Atherosclerosis is also called "hardening of the arteries." Cholesterol plaque and other fatty substances build up on the inner walls of arteries, causing them to narrow. Pieces of plaque from deposits on the inner walls of arteries can break off and travel throughout the body. They can cause a stroke if they block blood flow to the brain. Atherosclerosis can be especially dangerous if it affects the arteries in the neck, called the carotid arteries, because any clots that might break off will not have far to travel before reaching the brain.
Cigarette smoking has been linked to heart attacks, strokes, artery disease in the legs, and lung cancer. Nicotine raises blood pressure, carbon monoxide reduces the amount of oxygen the blood can carry to the brain, and cigarette smoke makes the blood thicker and more likely to clot. It is never too late to give up smoking.
Irregular heart beat (atrial fibrillation) is fairly common in old age, and increases the risk of stroke by causing blood clots to form in the heart. Blood clots can be prevented from forming by taking warfarin, a medicine that makes the blood less likely to clot. Warfarin treatment requires careful monitoring with regular blood checks and is a very effective way to reduce the risk of stroke.
Diabetes affects 1 in 20 older people, and can also increase the risk of having a stroke. Good control of diabetes is important and requires attention to diet, regular urine tests or blood tests, and probably some medication.
Too much alcohol increases the risk of a stroke. The recommended 'safe' limits for alcohol consumption are 21 units each week for women and 28 units each week for men. One unit of alcohol is equivalent to a measure of spirits, or a glass of wine, or half a pint of beer. People who drink more than this run a higher risk of stroke, liver disease and dementia.
In most age groups except older adults, stroke is more common in men than in women. However, it kills more women than men, regardless of ethnic groups. Women may have a higher risk for hemorrhagic strokes than men (although this risk is not consistent in all countries). It is not clear why women have a higher mortality rate from stroke. In one study comparing men and women with atherosclerosis (hardening of the arteries), the risk for stroke in women appeared to be higher with less blockage in the blood vessels. Another study also reported that women had a higher risk for fatal strokes after heart surgery. The arteries that lead to the brain may be more vulnerable to the effects of plaque buildup in women than in men.
All minority groups, including Native Americans, Hispanics, and African-Americans, face a significantly higher risk for stroke and stroke death than Caucasians. The risk is also higher in Asian Americans, although some evidence reports a marked decline in incidence in this group over the past decades. The differences in risk among all groups diminish as people age. The greatest disparity in risk occurs in young adults. Middle aged African-Americans are two to three times more likely to experience a stroke than their Caucasian peers and four times more likely to die from stroke. (They also face a higher risk for death from heart disease.)
Obesity may increase the risk for both ischemic and hemorrhagic stroke independently of other risk factors that often co-exist with excess weight, including insulin resistance and diabetes, high blood pressure, and unhealthy cholesterol level. Weight that is centered around the abdomen (the so-called apple shape) has a particularly high association with stroke, as it does for heart disease, in comparison to weight distributed around hips (pear-shape).