HDL cholesterol
At a Glance
Why Get Tested?
To determine the risk of developing heart disease
When to Get Tested?
As part of a health check with cholesterol or a lipid profile particularly if you:
- have a family history of cholesterol disorders
- have a family history of heart attacks, especially at a young age
- are overweight
- have diabetes
- have thick yellow patches (xanthomas) around your eyes or elsewhere on your skin
- have high blood pressure
- have had acute inflammation of the pancreas (acute pancreatitis)
- are a smoker.
Sample Required?
A blood sample drawn from a vein in the arm or from a finger-prick
Test Preparation Needed?
If this test is being performed as part of a complete lipid profile then fasting for 9-12 hours is required, only water is permitted.
The Test Sample
What is being tested?
HDL is one of the classes of lipoproteins that carry cholesterol in the blood. HDL is considered to be beneficial because it removes excess cholesterol and disposes of it. Hence HDL cholesterol is often termed ‘good’ cholesterol. The test for HDL measures the amount of HDL-cholesterol in blood.
How is the sample collected for testing?
The test for HDL-cholesterol uses a blood sample. Most often the blood sample is collected from a vein. Sometimes HDL-cholesterol is measured using a drop of blood collected by puncturing the skin on a finger. A finger-prick sample is typically used when HDL-cholesterol is being measured on a portable testing device.
Is any test preparation needed to ensure the quality of the sample?
If this test is being performed as part of a complete lipid profile then fasting for 9-12 hours is required, only water is permitted.
The Test
How is it used?
The test of HDL cholesterol is used to determine your risk of heart disease. If a high cholesterol is due to high HDL, a person is probably at low risk and further testing or treatment for high cholesterol is not advised.
When is it requested?
HDL is usually requested with other tests; either with cholesterol or as part of a lipid profile, including LDL and triglycerides. The combination of total cholesterol and HDL is very useful for screening for the risk of heart disease since it is not necessary to fast for these two tests. In contrast, a more complete lipid profile requires fasting for at least 12 hours.
What does the test result mean?
High HDL is better than low HDL. There are two ways that HDL cholesterol values are interpreted - as a percent of total cholesterol or as a measured value.
Percent: If HDL is 20% of the total cholesterol, the risk of heart disease is average. If HDL is more than 20% of the total cholesterol, the risk of heart disease is less than average. This is usually expressed as a ratio of cholesterol to HDL. It is desirable for the cholesterol/HDL ratio to be less than 5.
Measured value: If HDL is less than 1.0 mmol/L, there is an increased risk of heart disease. A desirable level of HDL is greater than 1.0 mmol/L and is associated with average risk of heart disease. A good level of HDL is 1.5 mmol/L or more and is associated with a less than average risk of heart disease.
HDL should be interpreted in the context of the overall findings from the lipid profile and in consultation with your doctor about other risk factors for heart disease.
Is there anything else I should know?
HDL cholesterol should not be measured when a person is unwell. Cholesterol is temporarily low during acute illness, immediately following a heart attack, or during stress (like from surgery or an accident). You should wait at least 6 weeks after any illness to have cholesterol measured.
In women, HDL cholesterol may change during pregnancy. You should wait at least six weeks after your baby is born to have your HDL-cholesterol measured.
Common Questions
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Article Sources
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