What is a lipid profile?
The lipid profile is a group of tests that are often requested together to determine risk of coronary heart disease. The tests that make up a lipid profile are tests that have been shown to be good indicators of whether someone is likely to have a heart attack or stroke caused by blockage of blood vessels (“hardening of the arteries”).
What tests are included in a lipid profile?
The lipid profile includes total cholesterol, HDL-cholesterol (often called good cholesterol), LDL-cholesterol (often called bad cholesterol), and triglycerides. Sometimes the report will 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.
How is a lipid profile used?
The lipid profile is used to guide providers in deciding how a person at risk should be treated. 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.
How is treatment determined?
Treatment is based on the overall risk of coronary heart disease as accessed after lifestyle modification. The following groups would be considered for treatment.
- Patients with vascular disease
- Type 2 Diabetics with LDL-cholesterol > 2.5 mmol/L or triglycerides > 2.0 mmol/L
- Patients with a family history of high cholesterol
- Aboriginal or Torres Strait Islander people with LDL-cholesterol >2.5 mmol/L
- Others with an elevated risk of cardiovascular disease
Pharmmceutical Benefits Scheme (PBS) Eligibility Criteria For Lipid Lowering Drugs may also be taken into account.
Recent trials support a target LDL-cholesterol of <2.0 mmol/L, a HDL-cholesterol of >1.0 mmol/L and a triglyceride of <1.5 mmol/L in patients being treated.
The first step in treating high LDL is targeted at changes in lifestyle – specifically adopting a diet low in saturated fat (the fat in dairy produce and meat) and participating in moderate exercise. You may be referred to a dietician for advice in making dietary changes.
If low-fat diets and exercise are not effective in lowering LDL-cholesterol to the target value, drug therapy would be the next step. There are several classes of drugs that are effective in lowering LDL. Your lipid profile will be checked at regular intervals to check that the drug is working. If the drug does not result in reaching your target LDL-cholesterol, your doctor may increase the amount of drug or possibly add a second drug.
What are 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)
- Age (45 or older for men; 55 or older for women)
- Family history of early heart disease (first degree relative affected before age 60)
- High blood pressure
- Physical inactivity
- Chronic renal failure
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. Many screening programs now offer both cholesterol and 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.