The lipid test is a blood test that targets the lipid compounds in the blood: cholesterol and triglycerides. The doctor prescribes it to determine, in his patient, the risk of developing cardiovascular disease.
How to interpret the results and what are the contraindications? In this article, we help you better understand lipid balance.
What is a lipid profile?
The lipid balance refers to an examination of the different lipid compounds present in the blood, namely:
- total cholesterol (a fatty substance that is used in the composition of cell membranes and is used for the synthesis of steroid hormones);
- LDL cholesterol, which is considered the “bad” cholesterol. The fatty substance is actually linked to transporters, LDL (for low-density lipoproteins) that navigate from the liver to the rest of the body;
- HDL cholesterol is referred to as “good” cholesterol. It is bound to HDL (high-density lipoproteins) that circulates to the liver. This is where cholesterol is stored;
- triglycerides (a type of fat that is an important energy reserve and comes mainly from sugars and alcohol ingested in large quantities).
Why perform a lipid assessment?
The lipid balance is not motivated by the appearance of a symptom, it is a routine examination that should be performed every 5 years in adults. It evaluates:
- the atherogenic risks of his patient, that is to say, the propensity for him to develop atheromatous plaques on his arterial walls;
- the risks of developing cardiovascular disease.
Atheromatous plaques are plaques essentially composed of lipids (but also blood, fibrous tissue, and calcareous deposit):
- they can cause damage to the lining of the arteries (called sclerosis);
- obstructing blood vessels;
- or even cause them to break up.
People with a known risk of cardiovascular disease should have this check-up more regularly:
- women over 60;
- men over 50;
- people with a family history of coronary heart disease (such as myocardial infarction), high blood pressure, diabetes, or smokers.
The test is also prescribed to check the effectiveness of a cholesterol or triglyceride treatment, or before prescribing a contraceptive pill for women.
How is the lipid balance performed?
To establish a lipid test, medical staff take a sample of venous blood, usually from the crease of the elbow. Then, it analyzes the components of interest:
- total cholesterol;
- LDL cholesterol;
- HDL cholesterol;
- and triglycerides.
In order not to distort the results and lead to a bad reading of the balance sheet, the patient must have been fasting for at least 12 hours. In addition, he must not consume alcohol during the 48 hours preceding the blood sample.
How to interpret the results of a lipid assessment?
Lipid status is considered normal when:
- total cholesterol: 2 g / l (the level is considered high if it exceeds 2.4 g / l);
- LDL cholesterol: 1 g/l (the level is considered high if it exceeds 1.6 g/l). Beyond that, we talk about bad cholesterol;
- HDL cholesterol is between 0.4 and 0.6 g/l. In this case, it is the good cholesterol;
- triglycerides: 1.5 g/l (the level is considered high if it exceeds 2 g/l).
Note that the reference values of these lipid parameters vary according to the age and sex of the patient. They may also vary slightly from country to country.
Taking into account the results of the assessment and the risks already known to the patient, the doctor will propose a treatment aimed at reducing the level of fats in the blood.
This is called lipid-lowering or cholesterol-lowering therapy: fibrates, resins, fish oils, or statins are usually recommended).
Contraindications and risks of lipid testing
For lipid testing, contraindications are identical to a blood test.
The existing risks are hematomas, discomfort, or transmission of diseases through the blood.
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