Lp(a) testing

Know your Lp(a) pathway

Why is this important?

One in 5 people worldwide are at increased risk of atherosclerotic cardiovascular disease due to a high Lp(a) level. Evidence for this was the focus of the 2022 Updated EAS Consensus Panel Statement on Lp(a).1

The 2019 European Society of Cardiology/EAS Joint Dyslipidaemia Guidelines recommend measuring Lp(a) at least once during an individual’s life.2 However, this is often overlooked in clinical practice. As Lp(a) concentration interacts with other risk factors to increase global cardiovascular risk, failure to take the Lp(a) level into account will underestimate this risk.

Knowing the Lp(a) is crucial for personalising risk factor modification to reduce the patient’s global risk of preventable cardiovascular disease.

If you know about high Lp(a) you can do something about it.

1. Kronenberg F, Mora S, Stroes ESG, et al. Lipoprotein(a) in atherosclerotic cardiovascular disease and aortic stenosis: a European Atherosclerosis Society consensus statement. Eur Heart J 2022;43:3925-46.

2. Mach F, Baigent C, Catapano AL, et al. 2019 ESC/EAS Guidelines for the management of dyslipidaemias: lipid modification to reduce cardiovascular risk. Eur Heart J 2020;41:111-88.

Lipoprotein(a): What clinicians need to know

Elevated lipoprotein(a) – often referred to as Lp(a) – is the most common dyslipidaemia, affecting one in 5 people worldwide. People with a high Lp(a) level are at increased risk of cardiovascular disease (CVD), such as heart attacks and stroke. But knowing the Lp(a) level, clinicians can take action to reduce the risk of preventable CVD in these patients.

What is Lp(a)?

Lp(a) is an LDL-like lipoprotein which also contains another lipoprotein, apolipoprotein(a).

Why is Lp(a) important?

The 2022 EAS Consensus Statement reinforced evidence for high Lp(a) as a causal risk factor for atherosclerotic cardiovascular disease (ASCVD) and aortic stenosis. This risk is independent of LDL C, as well as other risk factors.

What determines the Lp(a) level?

Lp(a) concentration is mainly determined by genetics (>90%), more than any other lipoprotein.

Are there differences in Lp(a) level by ethnicity?

Lp(a) concentration varies in different populations. The UK Biobank showed that median Lp(a) levels were highest in Black and lowest in Chinese people. However, there are very similar relationships between Lp(a) and ASCVD risk in White, Black, and South Asian individuals.

Does diet or lifestyle influence the Lp(a) level?

Lifestyle factors (diet and physical activity) do not have a major influence on plasma Lp(a) concentrations.

How is Lp(a) measured?

Lp(a) concentration can be measured as mass units (mg/dL or mg/L), or as particle numbers (nmol/L). The 2022 Consensus Statement does not recommend a standard factor to convert between these units as the mass of Lp(a) particles is variable.

Is a genetic test needed to assess Lp(a)?

No. Measuring the Lp(a) level in a blood sample is sufficient.

How often should Lp(a) be measured?

The 2019 ESC/EAS dyslipidaemia guidelines recommend measuring Lp(a) once in adults. Repeat testing is only required under certain circumstances. In youth, repeat testing may be indicated in certain patients.

Is there an Lp(a) threshold to increase cardiovascular risk?

No. The association between Lp(a) level and cardiovascular risk is continuous, even at low LDL-C levels.

What is a high Lp(a) level?

How much does a high Lp(a) level increase global cardiovascular risk?

The effect of a high Lp(a) needs to be interpreted in the context of the cardiovascular risk factor burden in the individual. A high Lp(a) value has a greater impact on absolute global risk if a person has several cardiovascular risk factors compared with those with none or a low number.

You can estimate the effect of the Lp(a) level on risk for heart attack or stroke using the Lp(a) clinical guidance risk calculator.

How do I manage a patient with a high Lp(a) level?

The focus of management should be early and intensive risk factor modification, which aims to mitigate global cardiovascular risk associated with a high Lp(a) level. The EAS Consensus Statement gives clinical guidance on management here.

Are all people with a high Lp(a) level at high risk of cardiovascular disease?

No. Global cardiovascular risk depends on the total burden of risk factors. People with a high Lp(a) level but no other major risk factors, could be at 50% lower risk for a cardiovascular event than people with a normal Lp(a) level but with other major cardiovascular risk factors.

If my patient has a high Lp(a) level do I need to consider testing family members?

Yes. This is because the Lp(a) level is >90% determined by genetics, and therefore hereditary. Testing is recommended in first-degree relatives (parents, children, and siblings).

When should I consider cascade screening?

Cascade testing for high Lp(a) is recommended if the individual has familial hypercholesterolaemia, there is a family or personal history of (very) high Lp(a), or personal or family history of premature cardiovascular disease.

EAS have independently organised all matters related to this activity. We gratefully acknowledge financial support from Novartis Pharma AG.

Testing services provided by Euromedix.

EAS gratefully acknowledge the contribution of FH Europe Foundation (FHEF) to this activity.