Lipoprotein-a

Definition

Lipoproteins are molecules made of proteins and fat. They carry cholesterol and similar substances through the blood.

A blood test can be done to measure a specific type of lipoprotein called lipoprotein-a, or Lp(a). A high level of Lp(a) is considered a risk factor for heart disease.

Alternative Names

Lp(a)

How the Test is Performed

A blood sample is needed.

How to Prepare for the Test

You will be asked not to eat anything for 12 hours before the test.

DO NOT smoke before the test.

How the Test will Feel

A needle is inserted to draw blood. You may feel slight pain, or only a prick or stinging sensation. Afterward, there may be some throbbing.

Why the Test is Performed

High levels of lipoproteins can increase the risk for heart disease. The test is done to check your risk for atherosclerosis, stroke, and heart attack.

It is not yet clear if this measurement leads to improved benefits for patients. Therefore, many insurance companies DO NOT pay for it.

The American Heart Association and American College of Cardiology DO NOT recommend the test for most adults who DO NOT have symptoms. It may be useful for people at higher risk because of a strong family history of cardiovascular disease.

Normal Results

Normal values are below 30 mg/dL (milligrams per deciliter), or 1.7 mmol/L.

Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.

The example above shows the common measurements for results of these tests. Some laboratories use different measurements or may test different specimens.

What Abnormal Results Mean

Higher than normal values of Lp(a) are associated with a high risk for atherosclerosis, stroke, and heart attack.

Considerations

Lp(a) measurements may provide more detail about your risk for heart disease, but the added value of this test beyond a standard lipid panel is unknown.

References

Genest J, Libby P. Lipoprotein disorders and cardiovascular disease. In: Zipes DP, Libby P, Bonow RO, Mann DL, Tomaselli GF, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 11th ed. Philadelphia, PA: Elsevier; 2019:chap 48.

Goff DC Jr, Lloyd-Jones DM, Bennett G, et al. 2013 ACC/AHA guideline on the assessment of cardiovascular risk: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation. 2013;129(25 Suppl 2):S49-S73. PMID: 24222018 www.ncbi.nlm.nih.gov/pubmed/24222018.

Semenkovich CF. Disorders of lipid metabolism. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 206.