Lp(a): The Hidden Heart Risk Your Routine Cholesterol Test Doesn't Measure

You get your cholesterol checked. Your LDL looks good, your HDL is healthy, and your triglycerides are under control. But there's an important cardiovascular risk factor your results don't reveal.

It's called Lipoprotein(a), or Lp(a). It's largely inherited, and elevated levels can increase the risk of heart attack, stroke and aortic valve disease.

Here's the catch: a standard cholesterol test does not measure Lp(a). You need a separate blood test to find out your level.

What Is Lp(a)?

Lp(a) is a cholesterol-carrying particle similar to LDL, often called "bad cholesterol." But it has an additional protein attached, called apolipoprotein(a).

This structure gives Lp(a) properties that can contribute to plaque buildup, inflammation and cardiovascular disease. Elevated levels are also associated with calcific aortic valve stenosis, a condition that causes the heart's aortic valve to become narrowed and stiff.

Unlike ordinary LDL cholesterol, Lp(a) is largely determined by genetics. Your level is generally established early in life and remains relatively stable throughout adulthood. Diet and exercise have little effect on it.

Why You May Not Know Your Level

A standard cholesterol panel measures:

• Total cholesterol
• LDL cholesterol
• HDL cholesterol
• Triglycerides

It does not ordinarily include Lp(a).

Consequently, someone can have apparently healthy cholesterol numbers and still carry an additional inherited cardiovascular risk.

Elevated Lp(a) is surprisingly common. The American Heart Association estimates that approximately one in five people worldwide has an elevated level. Most have no symptoms.

What Counts as High?

Lp(a) results are reported in either milligrams per deciliter (mg/dL) or nanomoles per liter (nmol/L).

These are general clinical categories. Risk increases progressively as Lp(a) rises.

One important caution: mg/dL and nmol/L are not directly interchangeable using a universal conversion formula. Ask your healthcare professional to interpret the result using the units reported by your laboratory.

Who Should Get Tested?

The 2026 American College of Cardiology and American Heart Association cholesterol guidelines recommend that every adult have Lp(a) measured at least once in their lifetime.

Testing is especially important if you have:

• A family history of early heart attack or stroke.
• A close relative with elevated Lp(a).
• Familial hypercholesterolemia.
• Cardiovascular disease that seems disproportionate to your other risk factors.

The test is a simple blood draw, and fasting is generally unnecessary. Because levels usually remain stable, one measurement is sufficient for most people.

If your level is elevated, close relatives—including parents, siblings and adult children—should consider testing too.

What If Your Lp(a) Is High?

There is currently no widely approved medication specifically targeting Lp(a) that has demonstrated a reduction in cardiovascular events. But an elevated result gives you important information about your overall risk.

The most effective approach is to manage the cardiovascular risk factors you can change.

"Control LDL cholesterol." Keeping LDL low is particularly important when Lp(a) is elevated. Depending on your risk, treatment may include statins, ezetimibe or PCSK9 inhibitors.

"Manage blood pressure and blood sugar." Both can add to cardiovascular risk.

"Maintain healthy habits." Exercise, a heart-healthy diet, avoiding tobacco and maintaining a healthy weight help reduce other cardiovascular risks, even though they generally don't lower Lp(a) itself.

"Don't abandon statins." Statins generally don't lower Lp(a) and may slightly increase it in some people. However, their established cardiovascular benefits remain important. An elevated Lp(a) result is not a reason to stop prescribed treatment.

Niacin can lower Lp(a) to some extent, but studies have not demonstrated that using it for this purpose prevents heart attacks or strokes. Supplements marketed as Lp(a)-lowering treatments should be approached with caution.

Can Niacin Lower Lp(a)?

Yes. Niacin (vitamin B3) can lower Lp(a) levels, typically by around 20–25%, although the response varies from person to person.

Niacin reduces the liver's production of apolipoprotein(a), a component of the Lp(a) particle. This makes it one of the few established treatments that can meaningfully reduce the measured level.

However, there's an important distinction: lowering Lp(a) does not automatically mean lowering cardiovascular risk.

Large clinical trials found that niacin did not provide additional protection against heart attacks or strokes when added to statin therapy, despite improving Lp(a) and other cholesterol measurements. For that reason, current guidelines do not recommend niacin specifically to reduce cardiovascular risk associated with elevated Lp(a).

Niacin also has potential side effects, including flushing, liver toxicity, increased blood sugar, and elevated uric acid. It should not be taken at high doses to lower Lp(a) without medical supervision.

The bottom line: Niacin can lower the Lp(a) number, but it has not been shown to reduce the additional cardiovascular risk associated with elevated Lp(a). A lower laboratory result is not necessarily a better health outcome.

Are New Treatments Coming?

Several experimental drugs use advanced genetic technologies to reduce the liver's production of apolipoprotein(a). Early studies have shown substantial reductions in Lp(a).

However, lowering a biomarker doesn't necessarily prevent disease.

In September 2026, Novartis announced that its Phase 3 Lp(a)HORIZON trial of pelacarsen did not meet its primary cardiovascular outcomes endpoint. Despite lowering Lp(a), the treatment did not significantly reduce the targeted cardiovascular events compared with placebo.

Other treatments remain under investigation. Researchers still need to demonstrate that substantially lowering Lp(a) actually prevents heart attacks and strokes.

EVIDENCE: STRONG

The inherited nature of Lp(a), its association with cardiovascular disease and recommendations for testing are well established. Whether specifically lowering Lp(a) reduces cardiovascular events remains an active research question.