High Cholesterol

What is High Cholesterol?

Cholesterol is a waxy substance that is made by the liver and obtained through the diet. It can be found in the fats (lipids) in your blood. High cholesterol is when you have high amounts of cholesterol in the blood.

Cholesterol is essential in order for your body to continue building healthy cells, however having high cholesterol can increase your risk of heart disease. This is because it can lead to a build-up of fatty deposits in your blood vessels, which overtime can make it difficult for enough blood to flow through your arteries and consequently to your heart.

What types of cholesterol are there?

"Good Cholesterol"

• High-density lipoprotein or HDL picks up excess cholesterol and takes it back to the liver. Having high HDL is linked to lower risk of heart disease, heart attack, and stroke

"Bad Cholesterol"

There are two types of cholesterol that can be considered bad/harmful:

• Low-density lipoprotein or LDL which carry cholesterol particles throughout your body. LDL cholesterol is bad because it builds up in the walls of your arteries, making them hard and narrow which can increase the risk of a heart attack.
• Lipoprotein(a), or Lp(a) - Unlike LDL and HDL cholesterol, which are influenced by lifestyle factors, Lp(a) is influenced by genetic factors. In Australia, doctors currently do not include this cholesterol marker in lipid panel tests. Current lipid panel tests only check for levels of HDL cholesterol, LDL cholesterol, total cholesterol, and triglyceride levels.
  

What are the symptoms of high cholesterol?

There are no symptoms of high cholesterol. The only way to detect it is through a blood test. High cholesterol can be inherited or is the result of unhealthy lifestyle choices. The best way to control high cholesterol is through a healthy diet, regular exercise, and medication.

What are the causes of high cholesterol?

High cholesterol can be caused by a number of factors including:

• Unhealthy diet, particularly high in saturated fats, trans-fats, and sugar
• Overweight or obesity
• Lack of exercise
• Age (cholesterol starts to rise after the age of 20)
• Smoking
• Family history

How is high cholesterol diagnosed in Australia?

A blood test, specifically a lipid panel or lipid profile, will show your total cholesterol levels.

The measured total cholesterol level is made up of your LDL cholesterol, HDL cholesterol and 20% of triglycerides (a type of fat in the blood).

For an accurate reading, you should not eat or drink anything between nine and twelve hours before the sample is taken.

In Australia, cholesterol levels are measured in millimoles per litre (mmol/L).

The range below is an Australian guide for a healthy blood cholesterol level.

• Total cholesterol should be between: 3.9 – 5.5 mmol/L
• HDL (good cholesterol) should be between: 0.9 – 2.1 mmol/L
• LDL (bad cholesterol) should be between: 1.7 - 3.5 mmol/L
• Triglycerides should be between: 0.5 – 1.7 mmol/L.
• Lp(a) should be: <100 nmol/L (this is approximately equivalent to <40mg/dL).

While we do not check for Lp(a), checking for the other cholesterol markers is one of the key checks that we do on the mobile Heart Health Check Tour, along with checking your blood pressure and sugar levels. This visual cholesterol guide is also available as a PDF to download.

Why are cardiologists calling to expand on this cholesterol test to include Lp(a) testing?

The Victor Chang Cardiac Research Institute, along with a growing number of cardiologists, are calling for doctors across Australia to start testing for Lp(a), which is now known to be a major risk factor for atherosclerosis. People with raised Lp(a) levels are 2-4 times more likely to develop atherosclerosis.

This simple blood test only needs to be completed typically once in a person's life. At risk groups recommended for testing includes males below 55 or women below 60 years with:

• a history of heart attack, stroke, angina, coronary stent or coronary bypass surgery, which is not explained by other risk factors
• or with a family history of early heart attack or stroke

Due to genetic factors influencing Lp(a) levels, family members of people found to have high Lp(a) should also be tested.

People with high Lp(a) should likely be referred to a cardiologist. Management may include addressing other risk factors, and increased monitoring. New targeted therapies to lower Lp(a) are currently in the final phase of clinical studies.

Does age make a difference to recommended cholesterol levels?

No, recommended cholesterol levels do not change based on age. It was once thought that high cholesterol becomes less of a problem as one ages. However, there is now good evidence that lowering high cholesterol is of benefit even in the elderly.

Previously, there was also concern that some cholesterol-lowering drugs like statins may interfere with one’s cognitive function (ability to think clearly) and that this might be more of an issue in the elderly. This has now been debunked. Nevertheless, it is worth starting with a low dose and gradually increasing to avoid any potential side effects.

How is high cholesterol treated?

Leading a healthy lifestyle through exercise and a healthy diet is important to avoid high cholesterol. If your cholesterol levels remain high, your doctor may recommend medication to help reduce the level. These include:

• Statins such as Crestor
• Bile-acid binding resins
• Cholesterol absorption inhibitors
• Injectable medication (a new class of drugs which can help the liver absorb more LDL cholesterol)

If you have high triglycerides, your doctor may recommend the following:

• Fibrates
• Niacin
• Omega-3 fatty acid supplement

How can high cholesterol be prevented?

To help reduce or prevent cholesterol you can:

• Eat a healthy diet
• Reduce salt
• Limit consumption of animal fats
• Eat healthy fats like avocados and salmon to increase HDL levels
• Avoid trans fats found in fried foods and baked goods
• Eat whole grains where possible
• Add more fibre to your diet
  
• Drink alcohol in moderation
• Lose excess weight
• Exercise regularly, starting with daily walking
• Quit smoking
• Know your family history

Ask your doctor for a heart health check which looks at the key risk signs. Download our Heart Health Check Guide to take with you to your next doctor's appointment.