Definition:
A total cholesterol test is a rough measure of all the cholesterol and triglycerides in your blood. Cholesterol is a soft, wax-like substance found in all parts of the body. Your body needs a little bit of cholesterol to work properly. But too much cholesterol can clog your arteries and lead to heart disease. Some cholesterol is considered "good" and some is considered "bad." Different blood tests are needed to individually measure each type of cholesterol. See also:
Alternative Names:
Total cholesterol 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 site is cleaned with germ-killing medicine (antiseptic). The health care provider wraps an elastic band around the upper arm to apply pressure to the area and make the vein swell with blood. Next, the health care provider gently inserts a needle into the vein. The blood collects into an airtight vial or tube attached to the needle. The elastic band is removed from your arm. 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, a sharp tool called a lancet may be used to puncture the skin and make it bleed. The blood collects into a small glass tube called a pipette, or onto a slide or test strip. A bandage may be placed over the area if there is any bleeding.
How to prepare for the test:
To get accurate results, you should not eat or drink anything for 9 to 12 hours before the test. You may drink water, but other beverages such as coffee, tea, or soda should be avoided. Your health care provider may tell you to stop taking drugs that can affect the test. Never stop taking any medicine without first talking to your doctor. Drugs that may increase total cholesterol measurements include: - ACTH
- Anabolic steroids
- Beta-adrenergic blocking agents
- Corticosteroids
- Birth control pills
- Phenytoin
- Sulfonamides
- Thiazide diuretics
- Vitamin D
Drugs that may decrease total cholesterol measurements include: - Allopurinol
- Androgens
- Colchicine
- Colestipol
- Fibrates
- MAO inhibitors
- Neomycin
- Niacin
- Statins
How the test will feel:
When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.
Why the test is performed:
This test is often done to determine your risk for coronary artery disease. High blood cholesterol and triglycerides have been linked to heart attack and stroke. Experts recommend that you have a complete cholesterol and triglycerides analysis every 5 years starting at age 20. The total cholesterol test is usually done as part of a lipid profile, which also checks for LDL, HDL, and triglycerides. Additional conditions under which the test may be performed:
References:
Implications of recent clinical trials for the National Cholesterol Education Program Adult Treatment Panel III guidelines. Circulation. 2004;110:227-239. Semenkovich CF. Disorders of lipid metabolism. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 217.
|