What Is Lipoprotein(a)?

Discover the Lipoprotein(a)-Heart Disease Connection

Senior man having a stroke/heart attack
What is lipoprotein?. Peter Dazeley / Getty Images

Lipoprotein(a), also known as Lp(a), is a low-density lipoprotein (LDL, or “bad” cholesterol) that has another form of protein, called a glycoprotein, bonded to it. (The name of this glycoprotein is apolipoprotein(a).)

Researchers are still working to understand lipoprotein(a) and the ways it may affect your health. However, some studies suggest that having high levels of lipoprotein(a) circulating in your blood could put you at a higher risk for developing heart disease.

What Does Lipoprotein(a) Do?

Made in your liver and then entering your bloodstream, lipoprotein(a) has been shown to build up under the inner lining of arteries. This buildup may contribute to the development of atherosclerosis —formation of fatty plaques in your arteries that can lead to heart disease, heart attack, and stroke—by promoting arterial inflammation (redness and swelling) and formation of foam cells, fatty cells that attach to atherosclerotic plaques. In addition:

  • High levels of lipoprotein(a) are believed to be most damaging to arterial walls when a person's level of LDL (“bad”) cholesterol is also high.
  • Higher lipoprotein(a) levels have been shown to lower the chances of survival in a person who’s had a heart attack.

What Levels of Lipoprotein(a) Are Considered Normal?

Blood test findings for levels of lipoprotein(a) are expressed in milligrams per deciliter (mg/dL). A level of 30 mg/dL is considered normal.

Findings higher than 30 mg/dL may indicate a 2- to 3-fold increased risk for heart disease.

However, lipoprotein(a) levels aren’t part of the routine lipid panel blood test, which measures levels of total cholesterol, LDL and HDL cholesterol, and triglycerides (a form of fat found throughout the body).

That’s because 1) not enough is known about lipoprotein(a)’s effect on heart health and 2) it’s found in only about 15% of the general population, with persons of non-Hispanic Caucasian, Chinese, and Japanese origins having the lowest levels.

That said, there are a few situations where it may be best to routinely check lipoprotein(a) levels. Mainly, these are when a person has:

  • Diagnosed heart disease and normal levels of HDL, LDL, and triglycerides
  • A strong family history of heart disease but, again, normal HDL, LDL, and triglyceride levels
  • Continuing high LDL levels despite receiving aggressive treatment

“Should I Try to Lower My Lipoprotein(a) Levels?”

Unfortunately, because lipoprotein(a) levels are mainly influenced by your genes, the usual recommendations – a healthy diet, regular exercise, and (most) cholesterol-lowering medications—do not have much effect on lowering them. Niacin has shown some promise in clinical studies for lowering lipoprotein(a) levels. However, it’s not routinely used for that purpose.

If you’re trying to lower your risk of developing heart disease, it’s best to put lipoprotein(a) on the treatment “back burner” for now and focus instead on methods for reducing the well-established risk factors for heart disease. As you probably know, these include lowering your blood pressure if it’s too high, lowering high LDL cholesterol, and raising low HDL cholesterol. Multiple studies have shown that targeting these risk factors can help reduce your risk of having a heart attack or stroke.

Sources:

Erquo S, Kaptoge S, Perry PL et al. Lipoprotein(a) concentration and the risk of coronary heart disease, stroke, and nonvascular mortality. JAMA 2009; 302:412-423.

Boffa MB, Koschinsky ML, Berglund L. Lipoprotein(a): a unique risk factor for cardiovascular disease. Clin Lab Med 2006;26:751-772.

“Test ID: LIPA-lipoprotein (a) serum.” Mayo Clinic-Mayo Medical Laboratories (2016). 

Kang S. “What is lipoprotein (a) and what does it mean for you?” HealthCentral (2008).   

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