Does this test have other names?
ApoB100, Apolipoprotein B, ApoB, Apolipoprotein (B)
What is this test?
This test measures the amount of a certain type of protein on the surface of cholesterol
called apolipoprotein B-100 (ApoB) in your blood. ApoB is the main protein found in
the low-density lipoproteins (LDL). LDL cholesterol is also called "bad" cholesterol
because high levels of it can damage your heart and arteries.
The ApoB test helps your healthcare provider figure out your risk for cardiovascular
disease. This is a disease that affects your heart and blood vessels.
Why do I need this test?
You may need this test if you have a family history of heart problems. You may also
need this test if you already have had heart problems such as a heart attack. And
you may need this test if you have a high level of fats, including cholesterol and
triglycerides, in your blood. High levels of fats may raise your risk for heart problems.
This test is also sometimes used to see how well treatment is working to bring down
high levels of fat in your blood.
What other tests might I have along with this test?
You may also need a test for total cholesterol called a lipid profile. This test measures
your blood levels of LDL cholesterol, high-density lipoprotein (HDL or "good") cholesterol,
and triglycerides. Comparing the percentages gives your provider a better idea of
your heart health.
You may also need blood tests for other markers that help see if you are at risk for
What do my test results mean?
Test results may vary depending on your age, gender, health history, the method used
for the test, and other things. Your test results may not mean you have a problem.
Ask your healthcare provider what your test results mean for you.
Results are given in milligrams per deciliter (mg/dL). Normal levels of ApoB-100 in
adults are less than 100 mg/dL. Your risk is high if you have a result greater than
High levels of ApoB may mean that you have a higher than normal risk of developing
cardiovascular disease. An ApoA test (linked with "good" cholesterol) may also be
done with the ApoB test. The ratio of the ApoA results and the ApoB results is sometimes
used as an alternative to a total cholesterol ratio to evaluate your risk of developing
How is this test done?
The test is done with a blood sample. A needle is used to draw blood from a vein in
your arm or hand.
Does this test pose any risks?
Having a blood test with a needle carries some risks. These include bleeding, infection,
bruising, and feeling lightheaded. When the needle pricks your arm or hand, you may
feel a slight sting or pain. Afterward, the site may be sore.
What might affect my test results?
Your test may be affected by:
Your eating habits, especially if your diet is high in fat
Taking medicines to lower cholesterol, such as statins
Having certain chronic diseases such as diabetes
How do I get ready for this test?
Follow any instructions you are given about not eating or drinking anything except
water for a time before the test. Ask your healthcare provider if you need to stop
taking any medicines before the test. Tell your provider about all medicines, herbs,
vitamins, and supplements you are taking. This includes medicines that don't need
a prescription and any illegal drugs you may use.