Lp(a): The Complete Guide

A calm, evidence-based, AHA-anchored read on the genetic cardiovascular risk marker your standard lipid panel doesn't include — what it is, what your number means, and what's actually worth doing about it.

What Lp(a) actually is

Lipoprotein(a), abbreviated Lp(a), is an LDL-like particle with an extra protein attached: apolipoprotein(a), or apo(a). The apo(a) protein is structurally similar to plasminogen — a protein involved in dissolving blood clots — which is part of why elevated Lp(a) increases not just atherosclerosis risk but also thrombotic event risk. The combination of LDL-like cholesterol cargo and a clot-promoting tail is what makes Lp(a) particularly atherogenic per particle.

The number you're given on a lab report is the concentration of Lp(a) particles in your blood, reported either as a mass measurement (mg/dL) or — preferred — as a particle count (nmol/L). The units are not interchangeable; conversion depends on the size of your specific apo(a) isoform, which varies between individuals. The American Heart Association and most major cardiology societies have moved toward nmol/L as the preferred reporting unit because it's less affected by isoform variation.

Roughly 80–90 percent of your Lp(a) level is determined by your genes — specifically, by variants in the LPA gene on chromosome 6. Once you've finished growing, your Lp(a) is essentially fixed for life. It does not vary with what you eat, how much you exercise, your weight, or your menopause stage. It is the most stable marker on a comprehensive lipid panel.

Why Lp(a) matters

Elevated Lp(a) is one of the most common inherited cardiovascular risk factors — and one of the most under-tested. Roughly 20 percent of adults globally carry Lp(a) at or above the elevated threshold. It contributes to coronary artery disease, stroke, peripheral vascular disease, calcific aortic stenosis (a degenerative valve condition), and venous thromboembolism. The mechanism is multi-pronged: Lp(a) deposits cholesterol in artery walls like LDL, but it also promotes inflammation, oxidative stress, and impaired fibrinolysis (clot dissolution).

Per the AHA's published guidance, Lp(a) of 125 nmol/L (50 mg/dL) or higher is associated with approximately a 1.4-fold increased long-term risk of heart attack or stroke. Lp(a) of 250 nmol/L (100 mg/dL) or higher is associated with at least a two-fold increased risk. These are population-average figures; the absolute risk increase depends on the rest of your profile.

The risk compounds. Someone with Lp(a) of 200 nmol/L plus LDL of 160 mg/dL plus a family history of early heart disease is in a fundamentally different risk category than someone with Lp(a) of 200 alone. The integrated picture — captured in the full lipid panel translator — is what determines what to actually do.

Why every adult should be tested at least once

The American Heart Association recommends that every adult be tested for Lp(a) at least once in their lifetime. The reasoning is mechanical:

• Lp(a) is stable for life. One accurate measurement is usually all you need. There is essentially no value in repeated testing unless the original measurement was suspect.
• Lp(a) is genetic. If yours is elevated, your first-degree relatives have roughly a 50 percent chance of carrying a similar level. They should be tested too. Cascade testing within families is a high-yield public health intervention.
• Lp(a) changes the interpretation of every other marker. The same LDL of 145 mg/dL means something different in someone with Lp(a) of 50 nmol/L versus 250 nmol/L. Knowing your Lp(a) sharpens every other clinical decision.
• Treatment landscape is changing fast. Multiple Lp(a)-targeted therapies are in late-stage trials. Knowing your number now means you're prepared to evaluate options as they become available.
• The test is cheap. $20–60 out of pocket at most major US labs. The cost-to-data ratio is unusually favorable.

Testing is especially important — beyond the universal recommendation — if you have:

• Family history of premature heart disease (heart attack or stroke before 55 in male relatives, 65 in female relatives)
• Personal history of cardiovascular disease, especially before age 50
• Familial hypercholesterolemia (FH) diagnosis or suspected FH
• Recurrent cardiovascular events despite controlled standard lipids
• Calcific aortic stenosis
• An ethnic background associated with elevated Lp(a) prevalence (notably South Asian and Black populations)

How to read your number

The AHA's published thresholds, in nmol/L (preferred) and mg/dL (older but still common):

A note on units: the rough conversion factor between mg/dL and nmol/L is approximately 2.5 (so 50 mg/dL ≈ 125 nmol/L; 100 mg/dL ≈ 250 nmol/L). The conversion is approximate — actual conversion depends on apo(a) isoform size, which varies between individuals. If your lab reported only mg/dL, request nmol/L for any future testing if available.

The risk multipliers above are population-average. Your absolute risk depends on the rest of your profile. Lp(a) of 175 nmol/L in a 32-year-old with no other risk factors is a very different proposition than Lp(a) of 175 nmol/L in a 62-year-old with elevated LDL, hypertension, and diabetes.

What to actually do if your Lp(a) is elevated

The honest, evidence-based answer is structural: you generally don't treat Lp(a) directly. You treat the markers you can move, more aggressively.

Tighten your LDL and ApoB targets. If your Lp(a) is elevated, the population-average LDL goal of under 100 mg/dL is no longer your goal. Many lipidologists target LDL under 70 mg/dL — the AHA's high-risk threshold — for adults with elevated Lp(a) but no other established disease. For those with Lp(a) above 250 nmol/L plus any other risk factor, under 55 mg/dL is reasonable. Same compression applies to ApoB — under 80 mg/dL for high-risk, under 65 for very-high-risk. Statin therapy remains first-line for reaching these targets.

Manage blood pressure tightly. Elevated Lp(a) plus elevated blood pressure is a particularly bad combination — the inflammatory and atherogenic effects compound. Most cardiology guidelines recommend keeping systolic blood pressure under 130 mmHg for adults with elevated Lp(a), tighter than the 140 threshold used for the general population.

Address other modifiable risk factors. Smoking cessation, weight management if applicable, diabetes control, regular aerobic exercise, sleep, and stress management all matter more when Lp(a) is elevated than when it's not. Lifestyle is the floor everything else builds on.

Consider a coronary calcium scan. Elevated Lp(a) is one of the strongest reasons to consider CAC imaging earlier than standard age-based screening recommendations. A score of 0 in someone with elevated Lp(a) is more reassuring than the same score in someone without — it suggests your lifetime exposure has not yet translated into calcified plaque. A positive score sharpens the urgency of every other intervention.

Tell your first-degree relatives. Cascade testing within families is a high-yield public health move. Your siblings, children, and parents have roughly a 50 percent chance of carrying a similar Lp(a) level. They should know to test.

Aspirin: maybe. The 2018 ACC/AHA guidelines pulled back on universal low-dose aspirin for primary prevention because of bleeding risk. But aspirin retains a specific niche: in adults with elevated Lp(a) and high cardiovascular risk, the antithrombotic benefit may outweigh the bleeding risk. This is a clinician conversation, not a self-prescribed move.

What about niacin, omega-3s, and supplements?

Niacin reduces Lp(a) by 20–30 percent at high doses, but the AIM-HIGH and HPS2-THRIVE outcome trials showed no cardiovascular benefit and meaningful harm (worsened glycemic control, infections, gastrointestinal effects). Niacin is no longer recommended for cardiovascular prevention.

Omega-3 fatty acids at supplemental doses do not meaningfully change Lp(a). Eicosapentaenoic acid (EPA) at high prescription doses (icosapent ethyl) reduces cardiovascular events in specific populations, but the mechanism is not Lp(a) reduction.

L-carnitine, coenzyme Q10, red yeast rice, and most over-the-counter supplements do not have evidence supporting Lp(a) reduction. Some red yeast rice products contain monacolin K (essentially a low-dose statin) but with unpredictable dose and contamination risk. Standard prescription statins are the more reliable path.

Lp(a)-targeted therapies — what's coming

The most exciting development in Lp(a) medicine is that targeted therapies finally exist in late-stage trials. They work by reducing apo(a) production in the liver, dropping Lp(a) levels by 80–95 percent. The leading candidates:

• Pelacarsen (Novartis) — antisense oligonucleotide; injection every 4 weeks; Phase 3 outcome trial (HORIZON) reading out 2025–2026.
• Olpasiran (Amgen) — siRNA; injection every 12 weeks; Phase 3 outcome trial (OCEAN(a)-Outcomes) ongoing.
• Lepodisiran (Eli Lilly) — siRNA; injection every 6 months; Phase 3 trials underway.
• Muvalaplin (Eli Lilly) — small-molecule oral agent that disrupts apo(a) assembly with apoB; Phase 2 data published; Phase 3 development progressing.

The open question for all of these is whether reducing Lp(a) translates to reduced cardiovascular events. The trials are designed to answer exactly that. Approval and uptake decisions over the next 2–4 years will be among the most consequential developments in preventive cardiology.

If you have very high Lp(a) and the standard treatment pathway feels inadequate, ask your clinician about clinical trial enrollment. ClinicalTrials.gov lists active trials by condition and location.

What changes the meaning of your Lp(a)

Other lipid markers. Lp(a) compounds with elevated LDL and ApoB. Same Lp(a) is far more concerning if your LDL is also high than if everything else is clean.

Family history. Lp(a) is genetic, so first-degree relatives with early heart disease often carry similar Lp(a). If your family history is strong, your Lp(a) is interpreted in a higher-risk context.

Existing cardiovascular disease. Lp(a) is a more urgent driver of secondary prevention than primary. If you've had an event, the answer is more aggressive lipid lowering and tighter risk-factor control across the board.

Age. Lp(a) is genetic, so the level itself doesn't change with age — but cumulative exposure compounds. Knowing your Lp(a) at 30 lets you act early; finding out at 65 after an event is a worse position to be in.

Ethnic background. Lp(a) prevalence and median levels vary by ancestry. Black and South Asian populations carry higher median Lp(a) than European-ancestry populations. The risk multipliers per unit of Lp(a) appear similar across groups — what differs is the proportion of the population at elevated levels.

How to actually get tested

Lp(a) is not part of the standard lipid panel at most labs. To get it measured, you have two paths:

Through your clinician. Specifically request "Lp(a)" or "lipoprotein(a)" — most clinicians will order it on patient request, especially with the AHA's universal-testing recommendation as backing. The test is non-fasting, so timing is flexible. Your insurance may cover it; if not, the out-of-pocket cost at major labs is typically $20–60.

Direct-to-consumer. Quest, Labcorp, and several DTC services (Function Health, LetsGetChecked) offer Lp(a) testing without a physician order in most US states. The advantage is speed and privacy; the disadvantage is the result lives outside your medical record unless you forward it.

Whichever path you choose, ask for the result in nmol/L if available. The AHA prefers it; the conversion from mg/dL is approximate.

Decode your full panel

Frequently asked

What is a normal Lp(a) level?
The AHA's elevated threshold is 125 nmol/L (50 mg/dL). Below that, you are at population-baseline risk for Lp(a). Above 125 nmol/L is elevated; above 250 nmol/L is high.

Should everyone get tested for Lp(a)?
Yes — the AHA recommends every adult be tested at least once in their lifetime. Because Lp(a) is genetically determined and stable, one measurement is usually enough.

Can I lower Lp(a) with diet or exercise?
Not meaningfully. Lp(a) is determined almost entirely by genetics. Diet, exercise, weight loss, and standard lipid-lowering medications (statins, ezetimibe) move it modestly at best. Statins can actually raise Lp(a) slightly. The clinical answer is to manage the markers you can move — LDL and ApoB — more aggressively when Lp(a) is elevated.

Why isn't Lp(a) on my standard lipid panel?
It's not part of the standard test. You have to specifically request it. The cost is typically $20–60 out of pocket if not covered. Despite the AHA's universal-testing recommendation, most adults have never had it measured — which is why we wrote an entire blog post arguing you should push for it.

How much does an elevated Lp(a) increase heart risk?
Lp(a) ≥ 125 nmol/L is associated with about 1.4× increased long-term risk of heart attack or stroke. Lp(a) ≥ 250 nmol/L is associated with at least 2× increased risk. The risk compounds with other markers.

Are there Lp(a)-specific medications?
Lp(a)-targeted therapies are in late-stage clinical trials (pelacarsen, olpasiran, muvalaplin, lepodisiran) and show 80–95 percent Lp(a) reduction in trial data. None are FDA-approved as of 2026. Whether reducing Lp(a) translates to reduced events is what the ongoing outcome trials are answering.

Can my children inherit Lp(a)?
Yes. Lp(a) is genetically determined, and first-degree relatives have roughly a 50 percent chance of carrying a similar level. If yours is elevated, your siblings, children, and parents should be tested.

Should I take aspirin if my Lp(a) is high?
Possibly. The 2018 ACC/AHA guidelines pulled back on universal aspirin for primary prevention, but adults with elevated Lp(a) and high cardiovascular risk may still benefit. Discuss with your clinician — this is not a self-prescribed decision.

Read your specific number

More likely useful

Educational guide. Not medical advice. Citations: AHA on Lipoprotein(a); CDC Lp(a) overview; ACC update on Lp(a); CCS 2021 lipid guidelines (referenced in our methodology page); ongoing pelacarsen, olpasiran, muvalaplin, and lepodisiran trials. Always discuss your numbers with a clinician who knows your full history.