Lp(a) Blood Test UK: The Inherited Heart Risk Your GP Probably Hasn't Checked

1. What Is Lipoprotein(a)?

Lp(a) is a type of low-density lipoprotein (LDL) particle with an extra protein called apolipoprotein(a) attached to its surface. This additional protein is structurally similar to plasminogen, a molecule involved in dissolving blood clots — which is why Lp(a) both promotes plaque build-up and impairs clot breakdown.

Think of LDL as a delivery van carrying cholesterol through your bloodstream. An Lp(a) particle is the same van, but with a sticky coating that makes it more likely to lodge in artery walls and harder for your body to clear.

Each Lp(a) particle carries one molecule of apolipoprotein B (ApoB), so it is counted in your total ApoB. However, unlike regular LDL, Lp(a) levels are 80–90% determined by your genes. Diet, exercise and most medications do not meaningfully change it.

2. Why Lp(a) Is Different From Other Lipids

Most cardiovascular risk factors respond to lifestyle changes. High LDL cholesterol can be reduced with diet. High triglycerides fall with weight loss and reduced alcohol. Even blood pressure responds to exercise, salt reduction and stress management.

Lp(a) does not follow these rules. Your level is set by the LPA gene on chromosome 6, specifically by the number of kringle IV type 2 (KIV-2) repeats in your apolipoprotein(a) protein. Fewer repeats produce smaller, more potent Lp(a) particles at higher concentrations. More repeats produce larger, less concentrated particles.

This has two practical implications:

• You only need to test once. Because Lp(a) is genetically determined, your level stays relatively stable throughout your life. A single measurement tells you your lifetime risk.
• Lifestyle changes will not fix it. If your Lp(a) is elevated, the strategy shifts to aggressively managing everything else — LDL, blood pressure, inflammation, metabolic health — to reduce your total cardiovascular burden.

This is precisely why the ESC 2019 dyslipidaemia guidelines recommend at least one Lp(a) measurement to identify people who need more aggressive risk management.

3. Who Should Get an Lp(a) Test?

The short answer: everyone, at least once. The EAS 2022 consensus statement explicitly recommends “measurement of Lp(a) at least once in each adult person's lifetime to identify those with very high inherited Lp(a) levels.”

Testing is especially important if you have:

• Family history of premature heart disease — a first-degree relative who had a heart attack or stroke before age 55 (men) or 65 (women)
• Familial hypercholesterolaemia (FH) or suspected FH — elevated Lp(a) is found in up to 30% of FH patients and compounds their already elevated risk
• Personal history of cardiovascular events — MI, stroke or peripheral artery disease, especially if it occurred despite well-controlled LDL
• Aortic valve calcification or stenosis — Lp(a) is independently associated with calcific aortic valve disease
• South Asian or Black African heritage — these populations have higher median Lp(a) levels than people of European descent
• “Borderline” cardiovascular risk scores — where knowing Lp(a) could reclassify you from intermediate to high risk and change treatment decisions

4. How Common Is Elevated Lp(a)?

Roughly 20% of the global population has Lp(a) levels above 50 mg/dL (125 nmol/L), the threshold associated with meaningfully increased cardiovascular risk. In the UK, that translates to approximately 1 in 5 adults — around 13 million people.

The distribution varies by ethnicity. The Atherosclerosis Risk in Communities (ARIC) study found that Black individuals have approximately 2–3 times higher median Lp(a) levels than White individuals. South Asian populations also tend to have higher levels.

Because the NHS does not routinely test Lp(a), the vast majority of people with elevated levels in the UK do not know they carry this risk. Unlike high cholesterol — which may be picked up during an NHS health check — elevated Lp(a) is a silent risk factor that requires proactive testing to detect.

5. Lp(a) Levels: What the Numbers Mean

Lp(a) is reported in either mg/dL or nmol/L depending on the laboratory. These units are not directly convertible because the molecular weight of Lp(a) varies between individuals (due to the variable kringle repeat structure). A rough conversion factor of 2.5 (nmol/L ≈ mg/dL × 2.5) is commonly used but is imprecise.

The EAS 2022 consensus identifies Lp(a) above 50 mg/dL (125 nmol/L) as the threshold for increased risk. However, risk increases continuously — there is no truly “safe” level, and people above 100 mg/dL (250 nmol/L) have a particularly high lifetime burden, comparable to heterozygous familial hypercholesterolaemia (NICE CG71) in terms of cumulative cardiovascular exposure.

Important: nmol/L is the preferred unit because it directly counts the number of Lp(a) particles. The ESC and EAS recommend laboratories report in nmol/L where possible.

6. Lp(a) and Cardiovascular Disease

Elevated Lp(a) increases the risk of three distinct cardiovascular conditions:

7. Lp(a) and Aortic Valve Stenosis

One of the most important discoveries about Lp(a) in the last decade is its role in calcific aortic valve disease. Mendelian randomisation studies — which use genetic variants as natural experiments — have shown that elevated Lp(a) is causally linked to aortic valve calcification and stenosis.

The Thanassoulis et al. 2013 study in the New England Journal of Medicine demonstrated that each standard deviation increase in Lp(a) was associated with a 1.6-fold increase in the odds of aortic valve calcification. This is thought to be driven by the oxidised phospholipids carried on Lp(a) particles, which promote calcium deposition.

Aortic stenosis is the most common valve disease requiring surgery in the UK, and currently the only treatment is surgical valve replacement. If Lp(a)-lowering therapies prove effective in clinical trials, they could potentially slow or prevent this condition — a prospect that underscores the importance of knowing your Lp(a) level.

8. Getting an Lp(a) Test in the UK

Lp(a) is not included in the standard NHS lipid panel. Your GP can request it, but most will not do so unless you specifically ask or have a known family history of premature cardiovascular disease.

The Helvy Heart Health panel (£89) includes Lp(a) alongside ApoB, hs-CRP, HbA1c and a full lipid profile — the advanced cardiovascular markers that the ESC recommends but the NHS does not routinely measure.

9. How to Interpret Your Results

When you receive your Lp(a) result, the first step is to check which units have been used (mg/dL or nmol/L) and compare against the risk thresholds in section 5 above.

10. Can You Lower Lp(a)?

Currently, no approved medication specifically targets Lp(a) reduction. However, some existing treatments have modest effects:

11. Emerging Lp(a)-Lowering Therapies (2024–2027)

Several pharmaceutical companies are developing therapies that specifically target Lp(a) production. These work by using antisense oligonucleotides (ASOs) or small interfering RNA (siRNA) to reduce the liver's production of apolipoprotein(a) — cutting Lp(a) at its source.

Note: none of these therapies are currently available outside clinical trials. If you have very high Lp(a) and established cardiovascular disease, ask your lipid specialist whether trial participation is an option.

12. Lp(a) and ApoB: Why You Should Test Both

Every Lp(a) particle carries one molecule of apolipoprotein B (ApoB). Your total ApoB count therefore includes both regular LDL particles and Lp(a) particles. This creates a clinically important interaction:

• If your Lp(a) is high, a significant portion of your ApoB comes from Lp(a) particles — which cannot be reduced by statins or lifestyle changes
• This means your residual ApoB after statin therapy may remain elevated, even if your LDL-C reaches target
• Knowing both values lets your doctor calculate how much of your atherogenic particle burden is modifiable (LDL) versus fixed (Lp(a)) — a critical distinction for treatment planning

This is why the Helvy Heart Health panel includes both Lp(a) and ApoB in the same test. Measuring one without the other gives an incomplete picture of your cardiovascular risk.

13. Family Screening (Cascade Testing)

Because Lp(a) is genetically determined, elevated levels run in families. If your Lp(a) is above 50 mg/dL (125 nmol/L), your first-degree relatives (parents, siblings, children) have a significant probability of also being elevated.

The EAS 2022 consensus recommends cascade screening of first-degree relatives when Lp(a) is elevated, similar to the approach used for familial hypercholesterolaemia (NICE CG71).

In practice, this means that if you discover you have high Lp(a), you may want to encourage your parents, siblings and adult children to get tested too. Early awareness allows for proactive risk management — particularly important for younger family members who have decades of cumulative cardiovascular exposure ahead of them.

14. When to See Your GP

Book a GP appointment if any of the following apply:

• Lp(a) above 50 mg/dL (125 nmol/L) — your GP should be aware and consider this when assessing your overall cardiovascular risk
• Lp(a) above 100 mg/dL (250 nmol/L) — referral to a lipid specialist may be appropriate, particularly if you have additional cardiovascular risk factors
• Elevated Lp(a) combined with elevated ApoB or LDL — the compounding risk may warrant more aggressive lipid-lowering therapy
• Family history of premature heart disease with elevated Lp(a) — cascade screening of relatives should be discussed
• Any new cardiovascular symptoms (chest pain, breathlessness on exertion, leg pain when walking) regardless of Lp(a) level

If your GP is unfamiliar with Lp(a), you may wish to bring a copy of the EAS 2022 consensus statement to your appointment. Many GPs have limited training in Lp(a) because it has not historically been part of routine cardiovascular risk assessment.

15. Frequently Asked Questions