Risk Factors

Risk Factors for Heart Disease

Over the last two decades, researchers have unearthed many risk factors for developing cardiovascular diseases. These include:

• Smoking. Smoking accelerates the development of atherosclerosis by constricting blood vessels, accelerating the formation of blood clots and restricting the amount of oxygen the blood supplies. Smokers who have heart attacks and strokes are more likely to die from them.
• High cholesterol levels. According to the National Cholesterol Education Program (NCEP), elevated LDL cholesterol is a major cause of coronary heart disease. That's why the NCEP panel recommends aggressive treatment. Treatment may include lifestyle changes, such as exercising more and reducing the amount of saturated fat in your diet, and medication. A combination of approaches is typically recommended.

Optimal cholesterol levels for healthy women are:

• Total cholesterol: less than 200 mg/dL
• HDL cholesterol: above 60 mg/dL. This range is considered to be protective against heart disease, while levels less than 40 mg/dL are considered a major risk factor for developing heart disease.
• LDL cholesterol: less than 100 mg/dL
• Triglycerides: less than 150 mg/dL
• High blood pressure (hypertension). When the heart works too hard to pump blood through the body, the intensity can damage the walls of the arteries of the heart and body.

A blood pressure reading records a systolic blood pressure—the highest pressure measured when the heart contracts with each beat, and a diastolic blood pressure—the lowest pressure measured in the arteries when the heart relaxes between beats. Optimal blood pressure is less than 120/80mm hg, read "120 over 80." Hypertension—high blood pressure—is defined as systolic pressure greater than or equal to 140 mm hg or diastolic pressure greater than or equal to 90 mm hg.

There is another category called "prehypertension" you should be aware of. This designation is made when the systolic pressure is 120 to139, or diastolic pressure is 80 to 89, and means you have a significant risk of developing high blood pressure, or hypertension.

• Diabetes. Having diabetes poses as great a risk for having a heart attack in 10 years as heart disease itself, according to NHLBI. In fact, cardiovascular disease is the leading cause of diabetes-related deaths. People with diabetes who have not yet had a heart attack have the same risk of future heart attack as someone with known coronary heart disease. Because their risk of heart attack is so high, NHLBI recommends that people with diabetes be treated aggressively with LDL-cholesterol lowering medication and carefully manage their blood sugar to reduce their cardiovascular risk.
• Age. Generally, women over age 55 and men over age 45 are at greatest risk for developing atherosclerosis. The risk of cardiovascular events increases with age.
• Family history. Family history is one of the biggest risk factors overall for atherosclerosis. Your risk is greater if your father or brother was diagnosed before age 55, if your mother or sister was diagnosed before age 65, or if you have a sibling with early coronary disease.
• Obesity. Overweight women are much more likely to develop heart-related problems, even if they have no other risk factors. Excess body weight in women is linked with coronary heart disease, stroke, congestive heart failure and death from heart-related causes.
• Inactivity. Not exercising contributes directly to heart-related problems and increases the likelihood that you'll develop other risk factors, such as high blood pressure and diabetes.
• Metabolic syndrome. This deadly quartet of abdominal obesity, high blood pressure, glucose intolerance (or pre-diabetes) and abnormal cholesterol is associated with a markedly increased risk of cardiovascular disease.
• Homocysteine. Homocysteine is an amino acid normally found in the body. Studies suggest that high blood levels of this substance may increase the risk of heart disease, stroke and peripheral vascular disease.
• C-Reactive protein (CRP), a high blood level of CRP, a sign of inflammation, may mean that the walls of the arteries in your heart are inflamed, which may raise your heart disease risk.

A blood test called the high sensitivity C-reactive protein blood test (hs-CRP) is now widely available. Most studies show that in healthy people, the higher the hs-CRP levels, the higher the risk of developing a future heart attack. In fact, scientific studies have found that the risk for heart attack in people in the upper third of hs-CRP levels is twice that of those with hs-CRP levels in the lower third. Recent studies also found a link between hs-CRP to sudden cardiac death and peripheral arterial disease.

According to the American Heart Association, numerous studies have examined whether hs-CRP can predict recurrent cardiovascular disease and stroke and death in various settings. High levels of hs-CRP consistently predict new coronary events in people with unstable angina and acute myocardial infarction (heart attack). Higher hs-CRP levels are also associated with lower survival rate in these people. Many studies suggested that after adjusting for other prognostic factors, hs-CRP was still useful as a risk predictor.

It is not yet known whether specific interventions will benefit those who have high hs-CRP, however aspirin therapy and cholesterol-lowering drugs might be helpful in these individuals.

The American Heart Association and the U.S. Centers for Disease Control and Prevention issued new guidelines for the blood test in January 2003. The guidelines recommend limiting the use of the CRP test as a discretionary tool for evaluating people of moderate risk, and not as a means of screening the entire adult population, as insufficient scientific evidence supports widespread use at this time.

Stress. Although stress has been implicated in the development of atherosclerosis, its exact relationship to heart disease has not been determined. Regular exercise can reduce stress and improve your mood.

Postmenopausal status. Your risk of developing atherosclerosis and heart disease increases once you reach menopause. Prior to menopause, women are mainly protected from heart disease by estrogen, the reproductive hormone produced by the ovaries. Among its many roles, estrogen helps keep arteries free from plaque by improving the ratio of LDL (low-density lipoprotein) and HDL (high-density lipoprotein) cholesterol. It also increases the amount of HDL cholesterol, which helps clear arteries of LDL cholesterol—the kind that most contributes to plaque build up.