What is Lp(a)?

And what do I need to know about it?

Published March, 23 2023

You likely know the importance of checking your cholesterol regularly and that high cholesterol isn’t ideal. But did you know that Lipoprotein(a), or Lp(a), is one important lipid reading not included in most standard laboratory tests? Moreover, researchers have recently discovered that knowing your Lp(a) level is essential to understanding your risk for heart and blood vessel (cardiovascular) disease.

It’s estimated that 1 in 5 people (63 million globally) have high Lp(a).¹ But because of the lack of testing, most people do not know if they have high Lp(a) and are at risk for cardiovascular disease until they have a heart attack or stroke.

It's easy to check your Lp(a) levels with Quest's Lipoprotein(a)/Lp(a) Test and High-Risk Heart Health Lipid and Lp(a) Panel. 

If you're interested in measuring your total cholesterol — including HDL cholesterol (good), LDL cholesterol (bad), and triglycerides — you might also consider Quest's Cholesterol (Lipid) Panel.

It's easy to purchase a test on questhealth.com and simple to schedule an appointment for sample collection at a nearby Quest Diagnostics location. You'll get fast results online and the option to discuss your results with an independent physician at no extra cost.

What is Lipoprotein(a)?

Lipoproteins, or lipids, are fatty, waxy substances found in every cell of your body. Lipoprotein(a), or Lp(a)—pronounced “L-P-little-A,” is one of a group of lipoproteins that carry cholesterol through the blood. This group of lipoproteins also includes Low-Density Lipoprotein (LDL) and High-Density Lipoprotein (HDL). 

Lp(a) looks like LDL cholesterol or “bad” cholesterol. But structurally, it has an extra apolipoprotein B attached to its surface. Lp(a) cholesterol is also “stickier” than LDL cholesterol and may be more likely to build up in the walls of your blood vessels, putting you at risk for cardiovascular disease (heart and blood vessel disease).

What are the signs or symptoms of high Lp(a)?

You may want to get tested if one or more of these apply to you:

• Family history of early onset heart or vascular disease 
• Elevated LDL cholesterol that doesn’t respond to medication
• Heart or vascular disease, with normal cholesterol and triglycerides without medication
• Think you may have inherited a genetic condition called familial hypercholesterolemia (FH)
• Have had more than 1 heart attack or procedure to open blocked arteries

How genetics and ethnicity play a role in Lipoprotein(a) levels

Lp(a) levels are tied to a specific gene in your DNA inherited from your parents. Lp(a) levels appear in your body by age five and remain the same throughout your life. While all ethnic groups are affected, Lp(a) is more common in African Americans and South Asians. Lp(a) levels may also rise in women and remain raised after menopause when estrogen levels decrease. Acute illness may also cause a temporary change in your level.

So, if you have a family member with a history of cardiovascular disease or high cholesterol, your Lp(a) levels may also be increased. Because Lp(a) levels are genetically determined, changes in diet or lifestyle cannot lower them.

What are the risks of having high Lipoprotein(a)?

Because Lipoprotein(a) particles are “stickier” than other types of bad cholesterol, they may be more likely to cause blockages and clotting. Research has shown that in people with high Lp(a), the risk for early heart disease and stroke is about 2-4 times higher than in the general population.¹ Despite the association between Lp(a) and heart attacks, checking the levels of Lp(a) flies under many doctors’ radars. This is in part because it is not as well-understood as other risk factors, and treatment options are still very limited.⁴

What does LP(a) do in the body?

Clotting- Lp(a) can cause increased clotting, leading to quickly formed blockages in blood vessels. The more Lp(a) plaques (fatty deposits) that build up, the greater the danger that a heart attack or stroke can occur.²

Inflammation- Lp(a) also promotes inflammation, increasing the likelihood that plaque deposits will burst. High Lp(a) levels can cause the narrowing of the aortic valve, called aortic stenosis, because of its role in inflammation. This chronic inflammation can also cause calcium buildup on the aortic valve, reducing blood flow.²

Medical conditions that may result from high Lp(a):

• Heart attack
• Stroke
• Coronary artery disease (narrowing/blocked arteries in the heart)
• Peripheral artery disease (blocked arteries in legs and arms) 
• Other conditions that affect the blood vessels