Also Known As
Lipoprotein little a
Formal Name
Lipoprotein (a)
This article was last reviewed on
This article waslast modified on 11 February 2018.
At a Glance
Why Get Tested?

As part of a targeted screen for cardiovascular disease (coronary artery disease (CAD) and cerebrovascular disease). Lp(a) measurement may give additional information about the risk of developing cardiovascular disease in some people

When To Get Tested?

Your doctor may request Lp(a) measurement if you have a family history of premature cardiovascular disease or elevated Lp(a) or if you develop cardiovascular disease at a young age, particularly in the absence of conventional risk factors

Sample Required?

A blood sample taken from a vein in your arm

Test Preparation Needed?

No test preparation is needed. Your doctor might recommend that you fast (water only) for 14 hours prior to the test so that other related substances can be measured in the same sample.

On average it takes 7 working days for the blood test results to come back from the hospital, depending on the exact tests requested. Some specialist test results may take longer, if samples have to be sent to a reference (specialist) laboratory. The X-ray & scan results may take longer. If you are registered to use the online services of your local practice, you will be able to access your results online.

If the doctor wants to see you about the result(s), you will be offered an appointment. If you are concerned about your test results, you will need to arrange an appointment with your doctor so that all relevant information including age, ethnicity, health history, signs and symptoms, laboratory and other procedures (radiology, endoscopy, etc.), can be considered.

Lab Tests Online-UK is an educational website designed to provide patients and carers with information on laboratory tests used in medical care. We are not a laboratory and are unable to comment on an individual's health and treatment.

Reference ranges are dependent on many factors, including patient age, gender, sample population, and test method, and numeric test results can have different meanings in different laboratories.

For these reasons, you will not find reference ranges for the majority of tests described on this web site. The lab report containing your test results should include the relevant reference range for your test(s). Please consult your doctor or the laboratory that performed the test(s) to obtain the reference range if you do not have the lab report.

For more information on reference ranges, please read Reference Ranges and What They Mean.

What is being tested?

Lp(a) is a risk factor for heart disease especially when LDL cholesterol is also raised. Lp(a) is a lipoprotein comprising a lipid rich core surrounded by an apolipoprotein (ApoB-100) and an apolipoprotein (a) molecule. In the body, apolipoprotein (a) can interfere with the function of plasminogen, which can result in blood clot formation and help LDL molecules bind to artery walls. This accelerates the development of plaques within the wall, which can then narrow and harden the artery. This dual action may explain the role of Lp(a) in the promotion of cardiovascular disease (CVD).

The size of the Lp(a) molecule is consistent for one person but it varies across the human population. Lp(a) size varies because its apolipoprotein (a) has a genetically determined, varying number of units (called kringles) in it. As the number of kringles rises, so does the size of the Lp(a) molecule. In people of European ancestry, larger forms of Lp(a) are associated with lower blood concentrations, while smaller forms are associated with a higher concentration. There is evidence that the smaller forms of Lp(a) are more atherogenic (promotes plaque formation and narrowing of the artery) than the larger ones. Most analytical methods only measure the concentration of Lp(a) and give no indication of molecular size.

Lp(a) concentrations within the blood are genetically determined and will remain fairly constant in an individual over a lifetime. Concentration is not affected by diet, exercise, and other lifestyle modifications used to lower lipids within the blood. Lp(a) concentrations  are slightly lower in men than in women and increase slightly in women after the menopause. The concentration of Lp(a) also varies with ethnicity: patients of African American descent can have concentrations up to 4 times higher than Caucasians, but they may not have a higher risk for CAD.

How is the sample collected for testing?

A blood sample is obtained by inserting a needle into a vein in the arm.

Is any test preparation needed to ensure the quality of the sample?

No test preparation is needed. Your doctor might recommend that you fast (water only) for 14 hours prior to the test so that other related substances can be measured in the same sample.

Accordion Title
Common Questions
  • How is it used?

    Lp(a) may be requested with other lipid tests in patients who have developed cardiovascular disease at a young age or who have a family history of premature heart disease. Its measurement will tell the doctor whether the concentration of Lp(a) is contributing to the patient’s risk of cardiovascular disease. Since the concentration of Lp(a) is largely genetically determined, lifestyle changes or treatment with statins or fibrates will usually be ineffective in lowering the concentration in the blood, although treatment with niacin or nicotinic acid may achieve a 20% reduction.  If an elevated concentration of Lp(a) is found,  your doctor will treat modifiable risk factors more aggressively to minimise cardiovascular risk.

  • When is it requested?

    Lp(a) may be requested, with other lipid tests, when you have a family history of premature coronary artery disease or of raised Lp(a), or you have developed symptoms of  cardiovascular disease at a young age which are not explained by conventional risk factors (e.g. high total cholesterol or LDL-cholesterol).

  • What does the test result mean?

    Lp(a) concentrations within the blood are genetically determined and remain relatively constant over an individual’s lifetime. They are not affected by lifestyle changes or by most drugs.

    High Lp(a) concentrations increase a person’s risk for developing coronary artery disease and cerebral vascular disease, especially in patients with hypercholesterolaemia Elevated concentrations of Lp(a) are thought to work independently, to add to any underlying heart or vascular disease processes. Conditions associated with elevatedconcentrations of Lp(a) include:

    Low concentrations of Lp(a) do not appear to cause problems. They may be seen with:

  • Is there anything else I should know?

    Although some cardiologists and other doctors occasionally request Lp(a), it is not a routinely used test. It is not routinely used and is currently not recommended for widespread testing. 

     In general, lipids should not be measured during a fever or major infection, within 4 weeks of an acute myocardial infarction (heart attack), a stroke, or major surgery, after excessive alcohol intake, when you have severely uncontrolled diabetes, when you are pregnant, or during rapid weight loss.

  • Why would my doctor want to request an Lp(a) more than once?

    Typically, Lp(a) measurement is usually only  requested once because the concentration will change very little. Occasionally your doctor may request a second Lp(a) blood test to confirm the initial result, or to see if your risk has increased significantly after menopause, or to monitor the effects of treatment.