The lipid profile, also known as the coronary risk panel, is comprised of total cholesterol, triglyceride, LDL-C (low density lipoprotein cholesterol), and HDL-C (high density lipoprotein cholesterol). It is usually used for evaluation of the risk for coronary heart disease and stroke. Testing lipid profile and especially cholesterol and cholesterol particles is the first step in screening for atherosclerosis risk, which might be the cause of heart attack and stroke. A heart attack or stroke is most commonly caused by blood vessels being blocked or by atherosclerosis (hardening of the arteries).
If through lipid testing it is discovered that a lipid disorder exists, treatments can be started to normalize lipid levels. Normalization can be achieved through medication, changes in diet, weight loss, and exercise. Therefore, this profile can be used as a screening test for risk evaluation for coronary heart disease and stroke, as well as diagnostic test for diagnosis and treatment monitoring of coronary heart disease, and familial hypercholesterolemia. It can be also used to monitor cholesterol and lipid-lowering lifestyle changes such as diet and exercise or to monitor cholesterol lowering drug therapy. Individuals with high blood pressure, tobacco smokers, individuals with a family history of cardiovascular disease, older people, and diabetes mellitus patients are at risk and should be screened. A more extended panel called NMR LipoProfile® test can be used for further screening and/or diagnosis. This test measures LDL particle number and size of LDL particles, as well as direct measurement of HDL and VLDL subclasses.
Cholesterol
Cholesterol is a steroid, a waxy substance that is found in the blood, tissues, and organs of all mammals including humans. Cholesterol is synthesized mainly in the liver. Metabolized cholesterol accounts for 75% of the cholesterol level, and diet accounts for the other 25%. Total cholesterol level in the body is dependent on many factors such as diet, liver function, lipid metabolism, heredity, and lifestyle choices. Testing serum cholesterol is the first step in screening for atherosclerosis risk.
Triglycerides
Triglycerides are stored in the fat cells of the body and serve as a main source of body energy. Triglycerides are absorbed in the intestine and are also synthesized in the liver. Elevated triglycerides are now considered an independent risk factor for coronary artery disease, and a major risk factor for acute pancreatitis, particularly when serum triglyceride levels are >1000 mg/dL.
High density lipoproteins (HDL)
HDL is responsible for the transport of cholesterol from the peripheral cells to the liver, where it is converted to bile acids which are excreted into the intestine via the biliary tract. Elevated HDL concentrations are protective against coronary heart disease, while reduced HDL concentrations indicate increased cardiovascular risk.
Low-density lipoprotein (LDL)
LDL belongs to a group of lipoproteins which serve as a transporter for cholesterol and lipids. Testing for LDL is used to evaluate the risk for coronary heart disease and stroke. High levels are associated with an increased risk of atherosclerosis and coronary heart disease and stroke.