Lp(a) Test: The Inherited Cholesterol Number to Check Once

My father died of a heart attack at 45. When I started reading about heart risk, one test kept coming up that almost nobody I knew had ever had: the Lp(a) test. It measures lipoprotein(a), a type of cholesterol particle that is set mostly by your genes, does not show up on a standard cholesterol panel, and can raise heart risk even when everything else looks normal.

What is Lp(a)?

Lipoprotein(a), written Lp(a) and pronounced “L-P-little-a”, is an LDL-like particle with an extra protein attached, called apolipoprotein(a). That extra protein makes it stickier: it helps build plaque in arteries, promotes blood clots and is linked with narrowing of the aortic valve (Kronenberg et al., 2022).

What makes Lp(a) different from ordinary LDL is where it comes from. Your level is largely inherited. It is set early in childhood, stays fairly stable for life, and responds very little to diet or exercise. A person can eat well, run marathons, have an LDL of 90 and still carry a high Lp(a).

Who should get an Lp(a) test?

The 2026 ACC/AHA dyslipidemia guideline recommends that every adult has Lp(a) measured at least once. Because the level hardly changes, one test is usually enough for life. It is especially worth asking for if:

• A parent, brother or sister had a heart attack or stroke at a young age (men before 55, women before 65).
• You or a relative have very high LDL or familial hypercholesterolemia.
• You had a heart attack or stroke yourself without obvious risk factors.
• Someone in your family has aortic valve stenosis.
• Your LDL is in a “gray zone” and you are trying to decide whether to start treatment.

If you have a family history like mine, it is a worthwhile test to ask about.

How to read your Lp(a) test result

Labs report Lp(a) in one of two units: nanomoles per liter (nmol/L), the preferred unit, or milligrams per deciliter (mg/dL). The two cannot be converted precisely, because Lp(a) particles vary in size from person to person, so compare your result with the cut-off in the same unit.

About one in five people has a level of 50 mg/dL or more (Kronenberg et al., 2022). The risk rises steadily with the level, so a result of 300 nmol/L matters more than a result of 130.

Can you lower Lp(a)?

Not much, with the tools available today, and it helps to be honest about that.

• Diet and exercise barely change Lp(a). They still matter a lot, because they lower your other risk factors.
• Statins lower LDL but do not lower Lp(a), and may raise it slightly. They remain very useful for people with high Lp(a), because they bring down overall risk.
• PCSK9 inhibitors, injectable LDL-lowering drugs, also lower Lp(a) by roughly a quarter. For people with heart disease and high Lp(a) whose LDL is still above goal on the highest statin dose they tolerate, the 2026 guideline recommends adding one.
• New drugs are still being tested. In September 2026, the first large outcome trial of an Lp(a)-lowering drug, pelacarsen, did not significantly reduce major cardiovascular events, even though it lowered Lp(a) (these are top-line results; the full data are still to come). Several other drugs, including olpasiran, lepodisiran and zerlasiran, are still in development, and none is FDA-approved.

What to do if your Lp(a) test is high

A high result on an Lp(a) test is not a diagnosis. It is a reason to be stricter about everything else you can control.

1. Know your 10-year risk. High Lp(a) counts as a risk-enhancing factor, which can tip the decision toward treatment. Start with our heart attack risk calculator.
2. Aim lower on LDL. Ask your doctor whether a lower LDL goal makes sense for you. Our guide to LDL cholesterol levels explains the goals.
3. Control blood pressure. It is one of the biggest risks you can actually change.
4. Do not smoke, stay active and keep your waist in check. Our guide to cardio for heart health after 40 is a good place to start.
5. Ask about a coronary calcium scan if you are a man 40 or older or a woman 45 or older at borderline or intermediate risk.
6. Tell your family. Because Lp(a) is inherited, your parents, siblings and children may want an Lp(a) test too.

Frequently asked questions

Is the Lp(a) test part of a normal cholesterol test?

No. A standard lipid panel measures total cholesterol, LDL, HDL and triglycerides. You have to ask for an Lp(a) test separately, by name.

How often should you test Lp(a)?

For most people, once. Levels are mostly genetic and stay stable through adult life, so the 2026 guideline does not call for routine repeat testing.

Does a high Lp(a) mean I will have a heart attack?

No. It raises your risk, but many people with high Lp(a) never have a heart attack, especially when they keep LDL, blood pressure and other risk factors under control.

Can diet lower Lp(a)?

Only a little, if at all. Diet still matters because it lowers LDL, blood pressure and weight, which reduces your overall risk.

For the full picture of your cholesterol, read cholesterol test results explained and cholesterol levels by age, or visit our heart health after 40 hub.

Sources

• Blumenthal R.S., Morris P.B., Gaudino M., et al. 2026 ACC/AHA/Multisociety Guideline on the Management of Dyslipidemia (Circulation, 2026)
• Kronenberg F., et al. Lipoprotein(a) in atherosclerotic cardiovascular disease and aortic stenosis: a European Atherosclerosis Society consensus statement (European Heart Journal, 2022)
• Koschinsky M.L., et al. A focused update to the 2019 NLA scientific statement on use of lipoprotein(a) in clinical practice (Journal of Clinical Lipidology, 2024)
• Lp(a)HORIZON: top-line results for pelacarsen, TCTMD (September 2026)
• Family Heart Foundation: the 2026 US dyslipidemia guideline and Lp(a) testing