Low-density lipoprotein (LDL) is a type of cholesterol the body synthesizes to transport triglycerides in the bloodstream. LDL cholesterol is known as the "bad" cholesterol because high LDL levels are associated with coronary heart disease. In general, an LDL level at or above 130 mg/dL is a major risk factor for development of coronary heart disease, and the target LDL goal for therapy depends on how many other risk factors are present. Always ask your physician if you have questions or concerns about your LDL risk status.
LDL Risk Levels
LDL cholesterol is tested as part of a blood lipid panel. LDL is measured in milligrams per deciliter (mg/dL). The U.S. National Institutes of Health National Cholesterol Education Program Adult Treatment Panel III categorizes LDL risk levels into five groups: less than 100 mg/dL is optimal; 100 to 129 is near optimal/above optimal; 130 to 159 is borderline high; 160 to 189 is high; and above 190 mg/dL is very high.
Other Risk Factors
The Adult Treatment Panel (ATP) III guidelines state the other major risk factors for heart disease include cigarette smoking; hypertension; low HDL cholesterol (less than 40 mg/dL); family history of premature coronary heart disease (CHD), meaning CHD in a male first-degree relative under 55 years or CHD in a female first-degree relative under 65 years; and age (men over 45 years, women over 55 years).
Optimal LDL levels
Besides your LDL cholesterol level, the National Cholesterol Education Program (NCEP) suggests modifying your LDL goals based on your number of risk factors for CHD. In general, the more risk factors you have, the lower you should set your target LDL goal for therapy. According to NCEP, a person with CHD or CHD equivalents should aim for an LDL level of less than 100 mg/dL; a person with two or more risk factors should aim for less than 130 mg/dL; and a person with zero or one risk factor should aim for less than 160 mg/dL. CHD risk equivalents include other clinical forms of atherosclerotic disease, diabetes or multiple risk factors conferring a 10-year risk for CHD of more than 20 percent.
History
The most recent ATP III guidelines use the same risk level groupings as the ATP II guidelines published in 1993. In other words, the ATP II set the LDL goal for primary prevention of CHD for patients with fewer than two risk factors at less than 160 mg/dL. The goal for primary prevention for patients with two or more risk factors was 130 mg/dL, and the goal for secondary prevention was 100 mg/dL. Your physician is the best resource for questions on how to manage high cholesterol.
Screening
LDL cholesterol is usually measured alongside HDL cholesterol, total cholesterol and blood lipids in what is known as a fasting lipoprotein panel or lipid panel. The U.S. National Institutes of Health recommends every adult 20 years or older obtain a lipid panel once every five years.
Considerations
References
- U.S. National Cholesterol Education Program: 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); 2001
- "Journal of the American Medical Association"; An Evidence Based Assessment of the NCEP Adult Treatment Panel II Guidelines; B. Ansell et al.; 1999
