Also known as:VLDL-C; VLDL
Formal name:Very Low-Density Lipoprotein Cholesterol
Related tests:Lipid Profile; Cardiac Risk Assessment; Triglycerides; LDL Particle Testing
Why Get Tested?
To help assess the risk of developing heart disease
When to Get Tested?
When other lipid tests, such as a lipid profile, are being performed
A blood sample drawn from a vein in your arm or a fingerstick
Test Preparation Needed?
Usually fasting for 9-12 hours before the test (only water permitted) and no alcohol for 24 hours before the test; follow any instructions you are given.
How is it used?
Very low-density lipoprotein cholesterol (VLDL-C) may be reported as part of a lipid profile, a group of tests that are often ordered together to determine risk of coronary heart disease and an important part of cardiac risk assessments.
Increased levels of VLDL-C are thought to reflect the presence of particles called lipoprotein remnants that are intermediate particles on the pathway of conversion of VLDL to LDL. When high levels of VLDL are present, the conversion of VLDL to LDL is slowed and the accumulation of intermediate particles is thought to contribute to the development of atherosclerosis and coronary heart disease.
When is it ordered?
VLDL-C is generally not ordered as a separate test. It may be reported with the results of a lipid profile when a health practitioner wants to determine a person's risk of heart disease.
What does the test result mean?
An elevated level of VLDL cholesterol (>30 mg/dL or >0.77 mmol/L), like elevated LDL cholesterol, is considered a risk factor for heart disease and stroke. The presence of high VLDL in addition to high LDL may affect the choice of therapy used to lower a person's cholesterol, such as lifestyle changes or drug treatment.
Low levels of VLDL cholesterol are not generally a concern.
Is there anything else I should know?
VLDL cholesterol concentrations, like all lipoprotein fractions, can be measured directly using techniques such as lipoprotein electrophoresis and ultracentrifugation. However, these techniques are complex and expensive and are not usually done in clinical laboratories. These tests are generally carried out in specialty laboratories, most often for research purposes.
What is being tested?
Very low-density lipoprotein (VLDL) is one of the four major lipoprotein particles. The other three are high-density lipoprotein (HDL), low-density lipoprotein (LDL), and chylomicrons. Each particle contains a mixture of cholesterol, triglyceride, and protein, but in varying amounts unique to each type of particle. LDL contains the highest amount of cholesterol. HDL contains the highest amount of protein. VLDL and chylomicrons contain the highest amount of triglyceride.
VLDL particles are released into the blood by the liver and circulate in the bloodstream, ultimately being converted into LDL as they lose triglyceride, having carried it to other parts of the body. According to the National Heart, Lung and Blood Institute's National Cholesterol Education Program Guidelines ATP III, there is growing evidence that VLDL plays an important role in atherogenesis, in which plaques form on the interior walls of arteries, narrowing these passageways and restricting blood flow, which can lead to heart disease and increase the risk of stroke.
At present there is no simple, direct way of measuring VLDL cholesterol. However, since VLDL-C contains most of the circulating triglyceride (if a person is fasting) and since the composition of the different particles is relatively constant, it is possible to estimate the amount of VLDL-C based on the triglyceride value.
To estimate VLDL-C, divide the triglyceride value by 5 if the value is in mg/dL or divide by 2.2 if the value is in mmol/L. This estimate is used in most settings. The calculation is not valid, however, when the triglyceride level is greater than 400 mg/dl (4.5 mmol/L) because other lipoproteins are usually present. Triglycerides testing most often requires that the patient fast before sample collection; otherwise these calculations may be invalid.
How is the sample collected for testing?
A blood sample is obtained by inserting a needle into a vein in the arm. Sometimes a drop of blood is collected by puncturing the skin on a fingertip.
NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.
Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.
Is any test preparation needed to ensure the quality of the sample?
Since VLDL-C is usually calculated from the triglyceride level, preparation is the same as for the triglyceride test. Current recommendations for this testing include fasting (having nothing to eat or drink except water) for 9 to 12 hours beforehand and avoiding alcohol consumption for at least 24 hours before the test. Follow any instructions you are given.
- How can I lower my VLDL-C level?
Because of the relationship between VLDL and triglycerides, you can lower your VLDL cholesterol level by taking steps to lower your triglyceride level. These include making healthy lifestyle changes, such as losing excess weight and exercising regularly. It has also been advised to avoid sugary foods and alcohol in particular since these have a strong effect on triglycerides. Cholesterol-lowering medication may also be recommended. Talk to your health care provider about what is right for you.
© 2017 American Association for Clinical Chemistry, republished from Lab Tests Online.*
Descriptions of clinical laboratory tests were originally prepared for use on Lab Tests Online, an award-winning patient education website on clinical laboratory testing. Lab Tests Online is produced by the American Association for Clinical Chemistry (AACC), a global scientific and medical professional organization dedicated to clinical laboratory science and its application to healthcare. The Lab Tests Online website is developed in collaboration with other laboratory professional societies and is funded in part through corporate sponsorships.