Lp(a): The Genetic Cardiovascular Risk Most Doctors Never Test

Lipoprotein(a) — pronounced "L-P-little-a" — is probably the most underappreciated cardiovascular risk factor in mainstream medicine. It's genetically determined, present in elevated levels in roughly 20% of the population, essentially unresponsive to diet or exercise, and triples to quadruples cardiovascular disease risk when elevated. The test costs under $40. Most doctors have never ordered it on their patients.

You should test Lp(a) once. If it's normal, you're done — it doesn't change. If it's elevated, the information permanently modifies your cardiovascular risk calculus.

What Lp(a) Is

Lp(a) is a modified LDL particle. The ApoB-100 on its surface is covalently linked to an additional protein called apolipoprotein(a) or apo(a). This apo(a) tail makes the particle behave differently from regular LDL:

• More efficiently retained in arterial walls (promoting atherosclerosis)
• More prothrombotic (apo(a) has structural similarity to plasminogen and interferes with fibrinolysis, potentially promoting blood clot formation)
• More pro-inflammatory in vascular tissue
• Carries oxidized phospholipids that accelerate plaque inflammation

The result: Lp(a) is both atherogenic (accelerates plaque buildup) and thrombogenic (promotes clot formation), a bad combination for cardiovascular events.

The Genetics

Lp(a) levels are roughly 90% genetically determined by variants in the LPA gene. Your Lp(a) level is established by adolescence and doesn't meaningfully change through life. Diet, exercise, and weight have minor effects. Alcohol, hormone changes, and a few medications have small effects. The number you get is effectively fixed.

This is why you only need to test once. A 30-year-old man's Lp(a) of 150 mg/dL will still be around 150 at age 70. If you test and it's 12 mg/dL, it'll remain around 12 forever.

Population distribution:

• Roughly 50% of people: under 30 mg/dL (low risk)
• Roughly 25%: 30-75 mg/dL (moderately elevated)
• Roughly 20-25%: above 75 mg/dL (elevated, significant risk)
• Roughly 5-10%: above 150 mg/dL (very high, major risk)

Ethnic differences exist. African-descended populations tend to have higher Lp(a); East Asian populations tend to have lower. But individual variation dominates.

The Risk Data

Mendelian randomization studies — using genetic variation as a natural experiment — are particularly strong here. People with genetic variants predicting higher Lp(a) have proportionally higher cardiovascular risk throughout life. The causation is clean.

Rough risk estimates:

• Lp(a) over 50 mg/dL: ~50% relative increase in cardiovascular disease risk
• Lp(a) over 100 mg/dL: ~2-3x relative risk
• Lp(a) over 150 mg/dL: ~3-4x relative risk

The risk is largely independent of LDL-C and other standard factors. A man with normal LDL-C and elevated Lp(a) has meaningfully higher risk than his standard lipid panel suggests.

Elevated Lp(a) is also associated with:

• Calcific aortic valve disease (the non-lipid-related form of aortic stenosis)
• Ischemic stroke (through both atherothrombotic and embolic mechanisms)
• Peripheral arterial disease
• Early-onset cardiovascular events when family members are affected

What You Can (And Can't) Do About It

Lp(a)-specific interventions are limited. As of 2026:

Drugs that lower Lp(a) modestly:

• Niacin (nicotinic acid) — lowers Lp(a) 20-30%, but fell out of favor due to lack of event reduction in trials and side effect burden
• Estrogen — not a treatment option for men
• PCSK9 inhibitors (evolocumab, alirocumab) — lower Lp(a) 20-30% in addition to their LDL effect
• Statins — minimal effect, sometimes slight increase in Lp(a)

Drugs in trials:

• Pelacarsen (antisense oligonucleotide) — lowers Lp(a) 80%+, phase 3 trial (Lp(a)HORIZON) expected to report 2026-2027
• Olpasiran (siRNA) — lowers Lp(a) 90%+, phase 3 trials ongoing
• Muvalaplin (oral) — first oral Lp(a) lowering drug, phase 2 showing 65-85% reduction, phase 3 planned

These drugs, if they confirm event reduction, will transform management of high-Lp(a) patients. Expect FDA decisions in 2027-2028.

The existing strategy for elevated Lp(a):

Since you can't directly lower Lp(a) meaningfully with current drugs, the strategy is to aggressively address everything else. If you have high Lp(a) and otherwise manage cardiovascular risk factors (cholesterol, blood pressure, metabolic health, lifestyle) to levels lower than a low-Lp(a) person would need, net risk is reduced.

Typical approach for elevated Lp(a):

• ApoB target under 60-65 mg/dL (tighter than standard)
• Blood pressure target under 120/80
• Aggressive weight management if applicable
• Zero tolerance for smoking
• Alcohol moderation
• Low-dose aspirin consideration (increased benefit in high-Lp(a) patients)
• Exercise optimization
• CAC scoring to quantify current disease
• Regular cardiovascular surveillance

Family Screening

If your Lp(a) is elevated, your first-degree relatives (parents, siblings, children) are at substantially higher probability of also having elevated levels. Their risk calculus also changes. They should test.

This is essentially cascade screening — one diagnosis reveals risk in a family, and intervention earlier in younger relatives can prevent events that would have seemed to come out of nowhere.

When to Test

Test Lp(a) once in adulthood. Any age after about 18-20 gives a stable result.

Priority testing:

• Family history of early cardiovascular disease (parent or sibling event before 55 in men, 65 in women)
• Personal history of cardiovascular events, especially if "unexplained" (normal LDL, no obvious risk factors)
• Family history of aortic valve disease
• Elevated ApoB or recurrent elevated LDL despite lifestyle efforts
• Decision-making about statin therapy (high Lp(a) argues for more aggressive lipid lowering)

Broader testing is increasingly recommended. European Atherosclerosis Society and Canadian guidelines recommend Lp(a) as part of one-time cardiovascular risk assessment in all adults. US guidelines haven't fully endorsed universal screening but many preventive cardiologists now recommend it routinely.

How to Get Tested

Standard blood draw. CPT code 83695. Reported in either mg/dL or nmol/L (unit confusion is common — ranges are similar but not identical).

Cost direct-to-consumer: $30-80. Quest and Labcorp both offer it. Often included in comprehensive panels.

Through insurance with physician order, routinely covered if clinical indication exists.

Fasting not required. One measurement is sufficient.

The Conversation to Have

If you haven't had Lp(a) measured, add it to your next blood panel. If your doctor doesn't order it routinely, request it specifically. The rationale: it's a one-time test that significantly modifies lifetime cardiovascular risk assessment, and new therapies on the horizon may make the information actionable within a few years.

Most men won't have elevated Lp(a). For those who do, knowing changes how aggressively to pursue other preventive measures. For the roughly 20% who are carrying this silent risk, the information is critical. For the rest, it's reassurance.

One test. One time. Worth the $40 and the blood draw.