Understanding Your Test Results

The only way to find out if your blood cholesterol levels are too high is to have your blood tested. High cholesterol has no symptoms and can develop with no warning signs. Unless you have a blood test, you may not know that you have high cholesterol until your health has been affected.

A simple blood test

The test for cholesterol levels is quite simple. A sample of blood will be taken from your arm and analyzed. Cholesterol tests provide your doctor with important information about the amount and types of fats in your blood stream.

What a cholesterol test measures

What is measured	What it tells your doctor
Total cholesterol	The total amount of all types of cholesterol in your blood.
Low density lipoprotein (LDL or "bad" cholesterol)	The amount of LDL cholesterol in your blood. LDL cholesterol can form fatty deposits, called plaque, that stick to the walls of your arteries and reduce the flow of blood to your heart.
High density lipoprotein (HDL or "good" cholesterol).	The amount of HDL cholesterol in your blood. HDL cholesterol reduces the amount of plaque on your artery walls by helping to remove cholesterol from your bloodstream.
Total cholesterol/HDL cholesterol ratio	The ratio of total cholesterol to HDL or "good" cholesterol in your blood. The total cholesterol/HDL ratio is a more sensitive measurement, and is considered to be a better indicator of heart disease risk, than total cholesterol alone. A low ratio of total cholesterol to HDL is associated with a lower risk of heart disease.
Triglycerides	The amount of triglycerides in your blood. Triglycerides are a type of fat that is strongly linked to heart disease, diabetes and high cholesterol.

What do the numbers mean?

In Canada, cholesterol measurements are given in millimoles per litre, which is abbreviated as: mmol/L.

The United States uses a different system of cholesterol measurement, which can sometimes cause confusion for people who travel back and forth between the two countries. In the U.S., cholesterol is measured in milligrams per deciliter, which is abbreviated as: mg/dL.

How do I know my cholesterol targets?

Your doctor will review the results of your cholesterol test. If your cholesterol levels are too high, your doctor will set targets for improvement and will monitor you regularly to see if you are meeting those targets. The good news is that most people can reach their cholesterol targets by making lifestyle changes, and, in some cases, taking medication.

In setting your cholesterol targets, your doctor will take into account a variety of factors that influence your risk of heart disease and stroke, including your age, gender, weight and lifestyle. Generally, your goal should be to keep your LDL levels low and your HDL levels high.

The new Canadian guidelines for lipid treatment and management¹⁹ have identified 3 main categories of heart disease risk and provide the following general recommendations for cholesterol targets:

*If your risk of heart disease is:**	Your LDL cholesterol target should be: AND	Your total cholesterol/HDL cholesterol ratio target should be:**
High (20% or higher)	less than 2.0 mmol/L AND	less than 4.0
Moderate (11-19%)	less than 3.5 mmol/L AND	less than 5.0
Low (10% or lower)	less than 5.0 mmol/L AND	less than 6.0

* based on your risk factors
** because this is a ratio, there is no unit of measurement

Triglycerides - the Canadian guidelines do not provide specific triglyceride levels for each risk category but recommend 1.7 mmol/L as the preferred triglyceride target for most people.

How often should I have my cholesterol tested?

Your risk factors and cholesterol test results will determine how often you need to be tested. High cholesterol can develop with no warning, so cholesterol testing is the best way to monitor your cholesterol levels.

Am I a candidate for regular cholesterol testing?

Regular blood tests are recommended for people who are at higher risk of developing high cholesterol. Routine cholesterol testing may be necessary if you:

are a man over 40
are a woman over 50
are a postmenopausal woman
have heart disease or have had a stroke
have diabetes
have a close relative (mother, father, sister, brother) with heart disease or high cholesterol
are overweight, physically inactive, smoke and/or drink excessively
have physical signs of high cholesterol such as fatty deposits on your skin or tendons
have high blood pressure