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The risk of a CVA increases with age; in fact, CVAs are among the leading causes of death and chronic disorders among older adults in the United States (Centers for Disease Control and Prevention, 2008a). In addition to age, other risk factors include being male, being African American, and having high blood pressure, heart disease, or diabetes. The higher risk among African Americans appears to be caused by a greater prevalence of hypertension in this population compounded by poorer quality and access to health care in general (Centers for Disease Control and Prevention, 2008c).
Treatment of CVA has advanced significantly. The most important advance is use of the clotdissolving drug tissue plasminogen activator (tPA) to treat CVAs (American Heart Association, 2008b). Currently, tPA is the only approved treatment for CVAs caused by blood clots, which constitute 80% of all CVAs. Not every patient should receive tPA treatment, and tPA is effective only if given promptly, which is vitally important. So if you or a person you know thinks they are experiencing a CVA, get medical attention immediately, because tPA therapy must be started within 3 hours after the onset of a stroke to be most effective. Recovery from CVA depends on the severity of the stroke, area and extent of the brain affected, and patient age.
Besides blood clots, high blood pressure plays a major role in CVAs. (Do you know what yours is?) Blood pressure consists of measuring two types of pressure: the pressure during the heart’s contraction phase when it is pumping blood through the body, called the systolic pressure, and the pressure during the heart’s relaxation phase between beats, called the diastolic pressure. The systolic pressure is always given first. On average, a blood pressure of 120 over 80 mm Hg (millimeters of mercury, the scale on which the pressure is measured) is considered optimal for adults. As we grow older, blood pressure tends to increase normally, mostly because of structural changes in the cardiovascular system. When blood pressure increases become severe, defined as 140 mm Hg or more systolic pressure (the top number in a blood pressure reading) or 90 mm Hg or more diastolic pressure (the lower number in the reading), the disease hypertension
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African American men are at especially high risk for hypertension.
results (American Heart Association, 2008c). Roughly 30% of the population age 20 and older has some degree of hypertension. This rate is roughly the same for European Americans and Mexican Americans, but jumps to about 42% among African Americans (Centers for Disease Control and Prevention, 2008c). This difference may be caused by a genetic mutation affecting enzymes that help control blood pressure and by environmental factors related to stress, poor access to health care, and poverty.
Hypertension is a disease you ignore at the risk of greatly increasing your chances of dying. Older adults with hypertension have three times the risk of dying from cardiovascular disease, and it has important negative effects on cognitive abilities and a host of other organs including kidney function (American Heart Association, 2008c; Centers for Disease Control and Prevention, 2008a). Because hypertension is a disease with no clear symptoms, most people with undiagnosed hypertension are not aware they have a problem. Regular blood pressure monitoring is the only sure way to find out whether you have hypertension. It could save your life.
What causes this silent killer? Two primary causes are stress and dietary sodium. Stress comes from many sources besides the more obvious ones that quickly come to mind (e. g., job). For example, Espino and Maldonado (1990) report that the rate of hypertension was higher among Mexican Americans who were more acculturated into the American lifestyle. In fact, degree of acculturation was a better predictor of hypertension than were socioeconomic variables such as income. They speculate that with acculturation come higher levels of stress and the adoption of a less healthful diet that puts such people at risk. Similarly, Cooper and colleagues (1999) showed that people of African descent around the world differ significantly in their rates of hypertension: Societies in which racism is a major social problem (especially the United States and the United Kingdom) have the highest rates.
Eating sodium in one’s diet is essential for life because the body needs a certain amount each day to regulate blood pressure and blood volume properly (McGee, 2007). Too much sodium can have several very bad health effects: In addition to hypertension, it can cause congestive heart failure and kidney disease (McGee, 2007). Sodium occurs naturally in many foods, such as raw celery, many cheeses, and scallops. It is also present in nearly all processed foods, often in high concentrations; for example, one serving of typical saltine crackers contains 1,100 milligrams, pretzels have 1,650, and a hot dog about 1,100. When you consider that the American Heart Association (2008d) recommends that adults should not consume more than 2,300 milligrams per day (about a teaspoon), it is clear that getting too much sodium is easy to do.
Another chronic cardiovascular condition that is discussed less often is hypotension, or low blood pressure. Symptoms of hypotension include dizziness or light-headedness that is caused most commonly when you stand up quickly after lying down or sitting, or sometimes after eating (Weinrauch,
2007) . Hypotension often is related to anemia and is more common in older adults. Although hypotension per se is not a dangerous condition, the resulting
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dizziness can increase the likelihood of fainting and falls, which may result in more serious injury.