What is being tested?

Lipids is the term used to describe the fats in the body.  Lipids may come from the diet (i.e. eating fatty foods) but the body is also capable of making its own lipids.  Whilst there are many types of lipids, the two lipids we measure in a lipid panel are cholesterol and triglycerides.

Lipids are transported in the blood in lipoproteins.  A lipid profile includes the measurement of cholesterol in two lipoproteins (high density lipoprotein (HDL) and low density lipoprotein (LDL)), as well as a measure of the total amount of cholesterol and triglyceride in the bloodstream.

The lipid profile typically includes measurement of total cholesterol, HDL-cholesterol (often called good cholesterol), LDL-cholesterol (often called bad cholesterol), and triglycerides. The report will probably include a calculation of non-HDL-cholesterol and may also include additional calculated values such as total cholesterol/HDL ratio or a risk score based on lipid profile results, age, sex, and other risk factors - a CVD Risk Assessment.

How is it used?

The lipid profile is a group of tests that are often requested together to determine risk of developing cardiovascular disease (heart disease, stroke and related diseases); and to monitor the treatment of conditions that  can cause blockage of blood vessels (atherosclerosis, sometimes known as “hardening of the arteries”).

When is it requested?

The lipid profile is used to guide healthcare providers in assessing the cardiovascular risk of an individual. The results of the lipid profile are considered along with other known risk factors of heart disease to develop a plan of treatment and follow-up.

The lipid profile is also used to assess the response to lipid lowering therapy.

What does the result mean?

The decision to treat someone with high cholesterol is based on the overall risk of cardiovascular disease which is assessed by considering a number of risk factors.  Online calculators such as CVD check are often used to assess this risk.

The decision to treat a patient with lipid-lowering drugs is an individual one and will be made by your doctor who will also take your wishes into consideration.  The following groups are recommended for treatment by the Royal Australian College of General Practitioners, although treatment may be recommended even if you do not fit into any of the categories below.

• Absolute cardiovascular risk >15%
• Patients with pre-existing cardiovascular disease
• Patients with diabetes and aged >60, or with diabetes-related kidney disease
• Patients with chronic kidney disease
• Patients with moderate or severe hypertension (high blood pressure)
• Patients with a total cholesterol >7.5mmol/L
• People of Aboriginal or Torres Strait Islander background aged >74
• Patients with familial hypercholesterolaemia (a genetic condition)

Targets for lipid lowering therapy, as recommended by the National Heart Foundation of Australia, are below.  These targets are only a guideline – your doctor may choose different targets based on your own individual circumstances and risk profile:

• Total cholesterol <4.0mmol/L
• HDL cholesterol >1.0mmol/L
• LDL cholesterol < 2.0mmol/L
• Non-HDL cholesterol <2.5mmol/L
• Triglycerides <2.0mmol/L

The first step in treating a high cholesterol is targeted at changes in lifestyle.  This may include adopting a diet low in saturated fat, and participating in exercise.  You may be referred to a dietician for advice in making dietary changes.  Lifestyle changes may be considered for all individuals regardless of their lipid results.

If you fit into one of the categories described above, or if your lipid profile does not improve sufficiently despite lifestyle measures, it is likely that your doctor will recommend lipid-lowering medication.  There are several classes of drugs that are effective in lowering lipids, although statins are most commonly used as first-line lipid lowering therapy.

Your lipid profile will be checked at regular intervals to ensure that the drug is working. If the drug does not result in reaching your target lipid profile, your doctor may increase the dose, or possibly add a second drug.

Is there anything else I should know?

Risk factors (in addition to high LDL) for coronary heart disease:

• Low HDL cholesterol (less than 1.0 mmol/L in men and less than 1.2 mmol/L in women)
• High triglycerides (>2.0 mmol/L)
• Age (45 or older for men; 55 or older for women)
• Family history of early heart disease (first degree relative affected before age 60)
• Smoking
• High blood pressure
• Obesity/overweight
• Physical inactivity
• Diabetes
• Chronic renal failure
• Excessive alcohol consumption

Common questions

• Do I need to fast for a lipid profile test?

Fasting specimens have traditionally been used for the formal assessment of lipid status. Recent evidence suggests that a non-fasting lipid profile may be acceptable, however this is yet to be endorsed by governing bodies in Australia.  Unless told otherwise, you should fast for 8-12 hours before the sample is collected.  Only water is permitted during the fast.

• I had a screening test for cholesterol. It was less than 5.5 mmol/L. Do I need a lipid profile?

If your total cholesterol is below 5.5 and you have no family history of heart disease or other risk factors a full lipid profile is probably not necessary. However, an HDL-cholesterol measurement would be advisable to make sure that you do not have a low HDL. 

• How often do I need a lipid profile test?

It has been recommended that healthy individuals with no other risks of heart disease should have cholesterol and HDL measured every five years. You do not need to have a full lipid profile. However, if you have other risk factors or have had a high cholesterol in the past, you should be tested more regularly and you should have a full lipid profile.

• My lipid profile results came back with high triglycerides and no LDL-cholesterol. Why?

In most screening lipid profiles, LDL-cholesterol is calculated from the other lipid measurements. However, the calculation is not valid if triglycerides are over 4.5 mmol/L. To determine LDL-cholesterol when triglycerides are over 4.5 mmol/L requires special testing techniques such as a direct LDL test or a lipid ultracentrifugation test.

• Should I have a more comprehensive lipid profile that includes lipid particle size?

This type of testing is expensive and not eligible for a Medicare rebate. In Australia the Lipoprint gradient gel electrophoresis test is available. It may be better at predicting risk than the routine lipid markers. However, the presence of small dense LDL is also predicted by the total cholesterol/HDL cholesterol ratio – which is recommended in the Australian cardiovascular risk calculator. The American Society for Clinical Pathology has recommended that these tests be used on an individualised basis for intermediate to high-risk patients only. They are not indicated for population based cardiovascular risk screening. 

• What is Familial Hypercholesterolaemia?

Familial hypercholesterolaemia (FH) is a severe form of elevated cholesterol levels that runs in families. It is often undetected until damage is done and the person develops cardiovascular disease. It can be easily screened for and treated early in life. Information about FH can be found at the FH Australia network site. Individual risk of having FH can be determined using this online calculator or using this form.

More Information

RCPA Manual: Lipids