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LDL test

• Overview
• Risks
• Results

Definition:

The LDL test measures how much low-density lipoprotein (LDL) you have in your blood. LDL is a type of cholesterol . Too much LDL in the blood can clog arteries.

Alternative Names:

Low-density lipoprotein test

How the test is performed:

Blood is drawn from a vein, usually from the inside of the elbow or the back of the hand. The puncture site is cleaned with antiseptic. An elastic band is placed around the upper arm to apply pressure and cause the vein to swell with blood.

A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. During the procedure, the band is removed to restore circulation. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.

In infants or young children, the area is cleansed with antiseptic and punctured with a sharp needle or a lancet. The blood may be collected in a pipette (small glass tube), on a slide, onto a test strip, or into a small container. A bandage may be applied to the puncture site if there is any bleeding.

How to prepare for the test:

You may be told not to eat or drink anything for 9 - 12 hours before the test.

The health care provider may tell you to stop taking certain drugs before the procedure.

How the test will feel:

When the needle is inserted to draw blood, you may feel moderate pain, or only a prick or stinging sensation. Afterward, there may be some throbbing.

Why the test is performed:

This test is usually done to determine your risk for heart disease. The LDL test is usually done as part of a lipid analysis , which also checks for total cholesterol, HDL, and triglycerides .

LDL is carries cholesterol to various tissues throughout the body. Too much LDL, commonly called "bad cholesterol," can lead to cardiovascular disease.

According to the National Heart, Lung, and Blood Institute, the lower your LDL, the lower your risk for heart disease or stroke.

References:

Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults. Executive Summary of the 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). JAMA . 2001;285:2486-2497.

• Review Date: 1/22/2007
• Reviewed By: Benjamin W. Van Voorhees, MD, MPH, Assistant Professor of Medicine and Pediatrics, The University of Chicago, Chicago, IL. Review provided by VeriMed Healthcare Network.

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