Medical Edge Newspaper Column

Lp(A) May Promote Healing, But Too Much Increases Risk of Heart Disease

June 6, 2008
Dear Mayo Clinic:
Could you explain Lp(a) and recommended treatment for this condition? Is there any new research?

Answer:
Lipoprotein(a), or Lp(a), is a type of cholesterol in your blood. The purpose of Lp(a) remains unclear, but some researchers think it may play a role in wound healing. Although Lp(a) is found naturally in the blood, if you have too much of it, Lp(a) can increase your risk of heart disease.

Specifically, Lp(a) is a type of low-density lipoprotein (LDL) cholesterol. LDL is sometimes called the"bad" cholesterol. An excess of LDL can cause build-up of fatty deposits (plaques) in your arteries (atherosclerosis), which reduces blood flow. The plaques can also rupture, leading to major heart and vascular problems.

Cholesterol levels are measured in milligrams (mg) of cholesterol per deciliter (dL) of blood. The risk of cardiovascular problems appears to be increased when levels of Lp(a) are more than 30 mg/dL.

For the most part, your Lp(a) level is determined by your genes and typically is not affected by lifestyle. Ethnicity seems to be a factor, with African Americans generally having higher levels of Lp(a) than other ethnic groups. Some medical conditions put you at higher risk of elevated Lp(a), too, including kidney disease and diabetes. Levels may increase in women after menopause.

Some medications can be used to lower Lp(a) levels. For example, nicotinic acid (niacin or Niaspan) has been shown to have Lp(a)-lowering effects. In women past menopause, the hormone estrogen has been shown to lower Lp(a) levels. However, no studies have shown that lowering Lp(a) levels alone will reduce the risk of cardiovascular problems in people who have elevated Lp(a).

On the other hand, lowering your overall LDL levels may decrease the ability of Lp(a) to form fatty deposits in your arteries. Researchers have found that in patients who have both high LDL cholesterol and high Lp(a), reducing LDL cholesterol, even if there's no change in Lp(a) levels, can decrease the risk of heart disease.

Currently, researchers are trying to find out more about how Lp(a) works and its role in the formation of plaque in the arteries. With that knowledge, they hope to be able to create new approaches for lowering Lp(a) levels that will, in turn, reduce the risk of heart disease.

— Iftikhar Kullo, M.D., Cardiovascular Diseases, Mayo Clinic, Rochester, Minn.