National Cholesterol Education Month suggests, "Know your cholesterol numbers, know your risk." This theme echoes two of the main thrusts of the cholesterol guidelines entitled, "Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults" (Adult Treatment Panel III, or ATP III).
These guidelines provide the most up-to-date recommendations on clinical cholesterol management for healthcare professionals. September, National Cholesterol Education Month, is a particularly good time to motivate individuals to get their cholesterol checked, know their numbers, and know their risk of developing coronary heart disease (CHD).
The Guidelines
ATP III, the first major update in cholesterol management from the NCEP in nearly a decade, follows the principles of previous panel reports. Important concepts from the previous cholesterol guidelines report – such as aggressively treating elevated low density lipoprotein (LDL) cholesterol in people with coronary heart disease – remain in place.
Some of the key changes in the ATP III guidelines include:
- More aggressive cholesterol-lowering treatment and better identification of those at high risk for a heart attack.
- Use of a complete lipoprotein profile as the first test for high cholesterol.
- A new level at which low HDL (high density lipoprotein) cholesterol becomes a major heart disease risk factor.
- A new, more powerful set of therapeutic lifestyle changes (TLC) to improve cholesterol levels.
- A sharper focus on a cluster of heart disease risk factors known as the "metabolic syndrome."
- Increased attention to the treatment of high triglycerides.
LDL cholesterol continues to be the primary target of therapy. Recent clinical trials affirm that lowering LDL cholesterol reduces the short-term risk for heart disease by as much as 40 percent, and the long-term reduction in risk may be even greater.
Assessing Your Risk
According to the ATP III, the intensity of cholesterol-lowering treatment should be matched to the person's level of risk for heart disease. Risk assessment in ATP III involves several straightforward steps. First, a complete lipoprotein profile (total cholesterol, LDL, HDL, and triglycerides) is obtained after a 9- to 12-hour fast.
Second, the presence of clinical atherosclerotic disease (clinical CHD, carotid artery disease, peripheral arterial disease, abdominal aortic aneurysm) is identified. Clinical atherosclerotic disease is considered a coronary heart disease risk equivalent, meaning that it confers the same high risk for CHD events as in those who already have CHD.
Third, the presence of major risk factors other than LDL is determined. The major risk factors exclusive of LDL are:
- Cigarette smoking (any in the last month).
- Hypertension (BP 140/90 mmHg or on antihypertensive medication).
- Low HDL (<40 mg/dL).
- Family history of premature CHD (CHD in male first degree relative <55 years; CHD in female first degree relative <65 years).
- Age (men 45 years; women 55 years).
Note: In ATP III, diabetes is considered a CHD risk equivalent because persons with diabetes have as high a risk of having a heart attack as someone who already has CHD.
Finally, if two or more risk factors (other than LDL) are present without CHD or CHD risk equivalent, Framingham risk scoring is used to estimate short-term (10-year) risk. Framingham risk scoring uses age, total cholesterol level, smoking status, HDL level, and systolic blood pressure to estimate 10-year risk for heart disease. ATP III divides those with multiple risk factors into three categories based on their 10-year risk for CHD: >20%, 10-20%, and <10%. The LDL goal of therapy is based on which of three categories of CHD risk the individual falls into:
- Persons with CHD or other clinical atherosclerotic disease, diabetes, or a 10-year risk >20% are placed in the highest risk group. The LDL goal for this highest risk group is <100 mg/dL.
- Persons with two or more major risk factors and a 10-year risk 20% have an LDL goal of <130 mg/dL.
- Individuals who have 0-1 major risk factor usually have a 10-year risk of <10%. The LDL goal for persons with 0-1 risk factor is <160 mg/dL.
Cholesterol-Lowering Therapy: Therapeutic Lifestyle Changes
ATP III recommends a multifaceted lifestyle approach to reducing cholesterol. This approach is termed therapeutic lifestyle changes (TLC) and includes the TLC diet, weight management, and physical activity. TLC is for anyone whose LDL is above their goal level. The TLC diet is a low saturated fat, low cholesterol eating plan that calls for less than 7 percent of calories from saturated fat and less than 200 mg of dietary cholesterol per day.
The TLC diet recommends only enough calories to maintain a desirable weight and to avoid weight gain. Increased amounts of viscous (soluble) fiber as well as food products containing plant stanols/sterols (such as cholesterol-lowering margarines) can also be added to the TLC diet to boost its LDL-lowering power. The other TLC components are weight management (especially for those who are overweight or obese) and increased physical activity. For additional information on TLC, visit the interactive Live Healthier, Live Longer Web page (www.nhlbi.nih.gov/chd/).
Cholesterol-Lowering Drug Therapy
While TLC alone may lower the LDL to goal in many persons, others (especially those with multiple risk factors and those with CHD or a CHD risk equivalent) may need a combination of TLC and drug therapy to lower their LDL cholesterol to goal. The choice of drug or drugs used will depend on the individual's lipid profile.
The statins are a frequently prescribed group of drugs that effectively lower LDL cholesterol and are safe for most users. In clinical trials, LDL cholesterol-lowering with statins has been shown to decrease the rate of heart attacks and deaths from CHD by approximately 30 percent. Statins have been shown to be effective in persons with or without CHD. To assist professionals in understanding the current recommendations for use and monitoring of statins, a clinical advisory on statins has been developed.
Bile acid sequestrants also lower LDL cholesterol and can be used alone or in combination with statin drugs. Nicotinic acid (or niacin) lowers LDL cholesterol and triglycerides and raises HDL cholesterol. Nicotinic acid in doses large enough to lower cholesterol can cause side effects and should only be used under the supervision of a physician. Fibric acids are used mainly to treat high triglycerides and low HDL. Regardless of the type of drug therapy used, individuals should take an active part in their health care. In order to maximize cholesterol lowering, TLC should always be maintained when drug therapy is prescribed.
The Metabolic Syndrome
The metabolic syndrome, which affects about one-quarter of all adults in the United States, has emerged as just as strong a contributor to early heart disease as is cigarette smoking. The metabolic syndrome, also known as syndrome X or insulin resistance syndrome, is a constellation of metabolic risk factors that significantly increases the risk for coronary events.
The metabolic syndrome is identified by the presence of three or more of the following: abdominal obesity (waist circumference >40 inches in men or >35 inches in women); triglycerides 150 mg/dL; HDL cholesterol <40 mg/dL in men or <50 mg/dL in women; blood pressure 130/85 mmHg; and fasting glucose 110 mg/dL. First-line therapy for the metabolic syndrome is TLC, especially weight loss and physical activity, to address the underlying causes of overweight/obesity and physical inactivity. |
