Definition This test measures the level of triglycerides, a kind of fat, in the blood. Triglycerides are different from cholesterol, which is often measured at the same time. High triglyceride levels can increase the risk of heart disease in some people. They can also cause inflammation of the pancreas when the level is extremely high.
Who is a candidate for the test? This test is performed to see how well the body processes fats. It is usually ordered as part of a "lipid," also called cholesterol or fat, profile to help evaluate risk factors for heart disease.
How is the test performed? To perform this test, a blood sample is needed. Blood is usually taken from a vein on the forearm or hand. First, the skin over the vein is cleaned with an antiseptic. Next, a strong rubber tube, or tourniquet, is wrapped around the upper arm. This enlarges the veins in the lower arm by restricting blood flow. A fine needle is gently inserted into a vein, and the tourniquet is removed. Blood flows through the needle, and is collected in a syringe or vial. After the needle is withdrawn, the puncture site is covered for a short time to prevent bleeding. The blood is then sent to the laboratory for testing.
What is involved in preparation for the test? When this test is ordered in the doctor's office, a person is often asked not to eat anything for at least 8 or 12 hours prior to the test. This is because the levels of triglyceride are often higher after eating, which is not abnormal. If the level is abnormally high after the person has not eaten, this is more likely to mean the body is having trouble processing fats. A person should request specific instructions from his or her doctor.
What do the test results mean? Normal triglyceride levels in the blood vary slightly depending on the age and sex of the person. The rough range of normal is from 0.1 - 2.1 mmols/L (millimoles per litre). In many cases, people are treated with diet or drugs to lower high cholesterol. Most experts advise trying to get the level of triglycerides below 2.0 mmols/L.
Abnormally high triglyceride levels may be due to:
an inherited, impaired ability to process fats that results in high levels of fats in the blood.
Other conditions may cause high or low levels, but are much less common.
Author: David T. Moran, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
