About the Test
Purpose of the test
The purpose of a lipoprotein (a) test is to evaluate whether you have high levels of lipoprotein (a) that can contribute to cardiovascular diseases like heart attack and stroke.
Lipoprotein (a) tests are mainly used for screening, which describes testing to identify health problems before they cause signs or symptoms. The goal of screening you for lipoprotein (a) is early detection of potential cardiovascular problems. Screening is most commonly recommended if you are already believed to have an elevated risk of cardiovascular disease. The test is not recommended as a screening test in the healthy population without other cardiovascular risks.
A test for lipoprotein (a) can also inform treatment decisions related to lowering cholesterol and reducing the risk of heart problems. For example, a doctor and patient may consider lipoprotein (a) levels when deciding whether to use cholesterol-lowering medications. In addition, lipoprotein (a) testing may be recommended if low-density lipoprotein (LDL) cholesterol levels do not decrease as much as expected when taking cholesterol-lowering medications.
What does the test measure?
The test measures the amount of lipoprotein (a) particles in a sample of blood.
Lipoprotein (a) is one of several lipoproteins, a mixture of fat and protein that transport cholesterol in the blood to cells throughout the body. Cholesterol is a waxy substance that enables normal cell function, but too much of certain kinds of lipoproteins and cholesterol can build up and damage arteries.
Lipoprotein (a) is classified as a LDL-like molecule consisting of an apolipoprotein B-100 attached to apoprotein (a). Cholesterol carried in LDL particles is known as “bad” cholesterol because of its association with cardiovascular disease. While lipoprotein (a) particles can transport cholesterol, the lipoprotein (a) particles themselves can also contribute to plaque buildup in the arteries, heightening the risk of heart attacks and stroke. Elevated lipoprotein (a) level is an independent predictor of coronary artery disease and heart attack, and is also a risk factor for abnormal clotting and stroke.
Lipoprotein (a) levels are largely driven by individual genetics. Unlike cholesterol levels, which are frequently linked to diet and other lifestyle choices, a person’s lipoprotein (a) levels are mostly determined by genes that can be passed down through families. Its levels vary significantly among different ethnic groups.
When should I get this test?
Lipoprotein (a) testing is not a routine type of cholesterol test, and it is usually reserved if you have already been determined to be at higher risk of cardiovascular problems.
There is no expert consensus about when to get a lipoprotein (a) test. Different medical organizations have distinct recommendations, but testing is more likely to be recommended if you have risk factors for cardiovascular disease such as:
- Past diagnosis of cardiovascular disease
- Very high levels of LDL cholesterol
- Family history of cardiovascular disease, especially if it occurred early in life and in more than one first-degree relatives
- High potential of having familial hypercholesterolemia, a hereditary disorder causing high levels of “bad” LDL cholesterol
A lipoprotein (a) test may provide information to help assess your cardiovascular disease risk. You may also be advised to have lipoprotein (a) testing if you and your doctor discuss the benefits and risks of medications to lower your cholesterol. For example, if you take cholesterol medications but have not seen the expected decrease in “bad” LDL cholesterol, the doctor may suggest lipoprotein (a) testing to better evaluate your cardiovascular health risks and help determine a better and individualized treatment plan.
Finding a Lipoprotein (a) Test
How can I get a lipoprotein (a) test?
Lipoprotein (a) testing is performed in a medical setting like a hospital, doctor’s office, or laboratory. The test is typically conducted after being ordered by a doctor, although you can also order a lipoprotein (a) test online.
Can I take the test at home?
At-home test kits are available for lipoprotein (a) testing. These self-collection tests involve obtaining a blood sample by pricking your finger with a small needle or visiting a nearby lab for a blood draw. With finger prick samples, after placing a drop of blood on a special test paper, you put the paper into an included mailer that is sent to a laboratory for analysis.
A test report showing your lipoprotein (a) level is accessed online and usually available within a week after your blood sample is received by the company’s lab.
How much does the test cost?
The cost of lipoprotein (a) testing depends on factors, including where the test is done, whether any other measurements are included, and whether testing is covered by health insurance. Complete lipoprotein (a) testing can include charges for the blood draw, office visits, and laboratory analysis of the test sample.
At-home lipoprotein (a) tests vary in costs depending on the lab being used and the type of sample collected.
Because lipoprotein (a) is not part of routine cholesterol testing, some insurance plans may not pay for testing even if your doctor prescribes it. For that reason, you should talk to your insurance company before testing.
Taking a Lipoprotein (a) Test
A lipoprotein (a) test is performed with a blood sample. The sample is normally taken by a health professional with a routine needle blood draw at a doctor’s office, laboratory, or hospital.
Before the test
Pretest instructions for a lipoprotein (a) test can vary based on the laboratory’s requirements and whether the test includes other measurements in addition to lipoprotein (a).
Sometimes you will be asked to fast before a lipoprotein (a) test, which means consuming no food or drinks besides water for eight to 12 hours beforehand. In other cases, fasting may not be required.
Some types of drugs may affect the test, so review with your doctor any prescription or over-the-counter medications and dietary supplements that you are taking.
Because test preparations can vary, it is essential to follow any specific pretest instructions from your doctor or the laboratory conducting your test.
During the test
A lipoprotein (a) test involves a routine blood draw during which a small sample of blood is taken from a vein in your arm.
To begin the test, a nurse or technician usually ties a band around the upper part of your arm, which increases blood flow in your veins. They use an antiseptic wipe to disinfect the skin near a vein and then insert a needle into the vein. A vial of blood is collected, and the needle is removed.
The entire blood draw usually takes less than a few minutes. There may be some pain or a sting when the needle is inserted and withdrawn, but it is rare to have any serious or long-lasting side effects.
After the test
Once your blood has been drawn and the needle has been removed, a bandage or cotton swab will be used to apply pressure and stop any continued bleeding.
If you are instructed to fast before the test, bringing a snack to eat right after the blood draw can be helpful. You can go back to driving and most normal activities without restrictions once the test is over.
Some pain, swelling, or bruising may occur in your arm, but these effects are usually mild and do not last long. If you have any signs of an infection or other worsening effects from a blood draw, contact your doctor directly.
Lipoprotein (a) Test Results
Receiving test results
The results from a lipoprotein (a) test are usually ready within a few business days after the laboratory receives your blood sample.
Your doctor may review the results with you at an appointment or by phone. You may also receive a detailed lipoprotein (a) test report by mail or via an online health portal.
Interpreting test results
Depending on the laboratory method used, lipoprotein (a) levels are reported in milligrams per deciliter (mg/dL) of blood or in nanomoles per liter (nmol/L) of blood.
The laboratory method can also affect the reference range for lipoprotein (a), so look closely at the test report to see the range of lipoprotein (a) levels considered normal for the specific laboratory that performed your test. Your doctor can review the results with you and explain whether they were normal or abnormal.
High lipoprotein (a) levels are considered a potential contributor to cardiovascular problems like the buildup of plaque in the arteries, heart attack, and stroke. In general, lipoprotein (a) levels above 50 mg/dL or 125 nmol/L are considered high risk for cardiovascular disease, heart attack and stroke.
Lipoprotein (a) levels are determined primarily by genetics and generally cannot be changed by diet or medication. However, if you have very high levels of lipoprotein (a) you may be advised to take more aggressive measures to lower your levels of “bad” LDL cholesterol.
Interpreting a lipoprotein (a) test result requires considering many factors including your age, results from other cholesterol tests, additional risk factors for cardiovascular disease, and your overall health. Your doctor is in the best position to review these considerations and explain the significance of your lipoprotein (a) test result.
After a lipoprotein (a) test, you can discuss the results with your doctor. The following questions may help you understand the test result:
- What was my lipoprotein (a) level?
- Does my lipoprotein (a) test result change how you evaluate my cardiovascular disease risk?
- Do you recommend any additional testing?
- Are there any medications or lifestyle changes you recommend based on my lipoprotein (a) and other cholesterol levels?