Lp(a): The Lesser-Known Cholesterol Level You May Need to Check

It's a fact: Cholesterol levels in American adults are sky-high. According to the Centers for Disease Control, about 86 million people in the U.S. have high cholesterol levels, which raises the risk of heart disease and stroke.

While cholesterol levels can vary depending on age, sex, and other health factors, you may have heard that a total cholesterol level of less than 200 mg/dL is considered "normal." You may also know there are two basic types of cholesterol to keep tabs on: The "bad" cholesterol is low-density lipoprotein (LDL), and the "good cholesterol" is high-density lipoprotein (HDL).

However, it turns out that LDL and HDL are not the only cholesterol levels that should be tested.

We spoke with Sonia Tolani, MD, co-director of the Columbia Women's Heart Center, who recommends that anyone getting their cholesterol checked as part of a physical exam should ask their doctor to run one more important cholesterol biomarker: Lipoprotein(a), known as Lp(a).

What is Lp(a)? What do we know about this "silent killer?"

Lipoproteins transport fats, known as lipids, such as cholesterol and triglycerides, and proteins through the bloodstream. Lp(a) is similar to LDL cholesterol (the "bad" one) but has an additional protein called apolipoprotein(a) attached to it. This unique protein structure can cause Lp(a) to accumulate in the walls of the arteries and form plaques, which can narrow and block blood vessels. 

Why Does Lp(a) matter?

Lp(a) levels are determined mainly by genetics, meaning some people are more likely to have higher levels than others. It's important to be aware of this risk because high levels of Lp(a) have been linked to an increased risk of heart disease, stroke, and other cardiovascular problems.

"Recent studies have shown that in people who have strong family histories of early heart disease, even if their standard lipid panel is normal, it's important to have Lp(a) checked because that can convey hidden risk for heart disease. Lp(a) may be as important of a predictor of cardiovascular disease as LDL cholesterol," says Dr. Tolani.

Are there treatments to reduce Lp(a) levels?

Despite its significant role in cardiovascular health, Lp(a) is not routinely measured in standard cholesterol lipid panel tests. Most people only know their Lp(a) levels if they specifically ask their doctor to test for it. But for people with a family history of heart disease, stroke, or other risk factors for cardiovascular disease, it may be worth testing Lp(a) levels. Higher levels may signal a need for more aggressive cholesterol-lowering medications and other interventions. 

"Currently, we know that Lp(a) is an important marker for risk for cardiovascular disease, but we don't yet know if it is a target to treat," says Dr. Tolani. "There are ongoing studies with certain medications that specifically reduce Lp(a), and we should know in the near future if there are additional benefits to using medications that specifically lower Lp(a) instead of those that just reduce bad LDL cholesterol, such as statins."

Some new therapies that hold promise to reduce Lp(a) levels include antisense oligonucleotide therapy and PCSK9 inhibitors.

What are the best everyday habits for lowering Lp(a) and other cholesterol levels?

Dr. Tolani wants us to know that there are things we can do right now to lower cholesterol and cardiovascular disease risk. Maintaining a healthy weight, eating a heart-healthy diet, exercising regularly, quitting smoking, and managing other health conditions such as high blood pressure and diabetes can help.

Dr. Tolani suggests, "If your cholesterol levels are high, lifestyle changes and medications can help lower them and reduce your risk of heart disease. It's important to talk to your doctor about your cholesterol levels and what you can do to keep them in a healthy range."

Even if you don't ask your doctor about your Lp(a) levels, checking your basic cholesterol is still important. Studies show that a third of Americans have not checked their cholesterol levels within the last five years. The first step is to talk to your doctor, who can help you determine if it's necessary to test for Lp(a) and order the appropriate blood test.