Heart disease, along with stroke and blood vessel disease, belongs to the group of conditions together known as cardiovascular disease (CVD). Cardiovascular disease is a leading cause of death in Australia. 41,849 deaths were attributed to CVD in Australia in 2018.
Cardiovascular disease can occur when arteries that supply blood and oxygen to your heart muscle and other organs (such as the brain and kidneys) become clogged with fatty material called plaque or atheroma. This process is called atherosclerosis. It can start when you are young and be well advanced by the time you reach middle age.
If your arteries become too narrow, less blood can reach your heart muscle or your brain. When this happens in arteries of the heart, it can lead to symptoms such as angina (chest pain). If a blood clot forms in the narrowed artery and blocks the blood supply to part of your heart, it can cause a heart attack. If this happens in the arteries supplying blood to the brain, this can cause a stroke.
Understanding your cardiovascular disease risk score
In the past, your doctor may have measured and treated each of your CVD risk factors one at a time. It is now recommended that overall risk be assessed to determine your personal heart disease and stroke-risk score.
Risk score puts many of the risk factors together. This is a bit like putting all the pieces of a puzzle together so you can see the whole picture. By looking at the whole picture, your doctor can discuss ways to reduce your risk of stroke or heart attack. Risk reduction strategies include medications, surgery and lifestyle changes.
However, if you are already known to be at high risk (for example, if you have had a previous heart attack or stroke, have severe kidney disease, very high blood pressure or have diabetes and are over 60 years old), a risk score will not need to be calculated. Your doctor will tell you if you are in this group and advise you about what to do to reduce your risk.
Heart disease and stroke risk factors
There is no single cause for CVD, but there are risk factors that increase your chance of a heart attack or stroke. There are modifiable factors (ones that you can change) and non-modifiable factors (ones that you can’t change).
Heart disease and stroke risk factors that you can change include:
Social isolation and lack of social support are risk factors for CVD that can be changed, although it can seem challenging. One way to help with loneliness is to learn how to improve your social connections.
Risk factors you can’t change include increasing age, being male, being post-menopausal and having a family history of CVD. Aboriginal and Torres Strait Islander people are also at increased risk of CVD.
The good news is that you can reduce your overall risk of developing CVD by leading a healthy lifestyle and taking medicines as prescribed by your doctor.
Smoking and cardiovascular disease risk
As well as causing cancer, smoking affects the arteries that supply blood to your heart and other parts of your body. It reduces the amount of oxygen in your blood and damages your artery walls.
Smoking increases your risk of heart attack, stroke and peripheral vascular disease (also known as peripheral artery disease) – which can lead to gangrene and limb amputation).
Smoking makes your blood ‘stickier’, causing blood cells to clump together. This slows blood flow through your arteries and makes blockages more common. Blockages may cause heart attack and stroke.
Smoking also makes your artery walls sticky, causing them to become clogged with fatty material called plaque or atheroma. Smokers often have cold hands or feet as a result of clogged arteries, which may also lead to serious problems such as gangrene.
If your coronary artery becomes clogged, it can cause angina. If a blood clot forms in the narrowed coronary artery and completely blocks the blood supply to a part of your heart, it can cause a heart attack.
Cholesterol and cardiovascular disease risk
Cholesterol is a fatty substance produced naturally by your body (blood cholesterol). It is used for many different things in your body but is a problem when there’s too much of it in your blood.
High total cholesterol causes fatty material to gradually build up in your body’s arteries, making it harder for blood to flow through. It is mainly caused by eating foods high in saturated fats and trans fats.
Your total cholesterol includes two types of cholesterol, which are:
- low-density lipoprotein (LDL) – also known as ‘bad’ cholesterol because it can add to the build-up of plaque in your arteries and increase your risk of heart attack and stroke.
- high-density lipoprotein (HDL) is also known as ‘good’ cholesterol because it helps to protect you against heart attack and stroke.
Most of the total cholesterol in your blood is made up of ‘bad’ LDL cholesterol. Only a small part is made up of ‘good’ HDL cholesterol.
You should aim for low LDL cholesterol and higher HDL cholesterol on advice from your doctor. If you are having trouble with your cholesterol levels, a dietitian can help you to eat healthily for your specific needs.
Blood pressure and cardiovascular disease risk
Blood pressure is the pressure of the blood in your arteries (the blood vessels that carry oxygen and nutrients to your body) as it is pumped around your body by your heart. Blood pressure depends on two main things: the amount of blood pumped by your heart and how easily the blood can flow through your arteries.
Your blood pressure will go up and down throughout the day, depending on the time of day and what you are doing. However, high blood pressure is a condition where your blood pressure is consistently high.
Your family history, eating patterns, alcohol intake, weight and level of physical activity have a strong influence on blood pressure. In some people, medicines, including the oral contraceptive pill, contraceptive ‘depot’ injections, steroids (cortisone-like medicines) and arthritis medicines, can also raise blood pressure.
High blood pressure can overload your heart and arteries and speed up the artery-clogging process. This can lead to problems such as heart attack and stroke.
High blood pressure can also affect arteries to other parts of your body, such as the eyes, kidneys and legs.
If high blood pressure is not treated, your heart may weaken because of the constant extra demand. This may cause ‘heart failure’, a serious condition with symptoms such as tiredness, shortness of breath and swelling of the feet and ankles.
Diabetes and cardiovascular disease risk
People with diabetes are at greater risk of heart attack, angina and stroke. Similarly, people with CVD are generally prone to diabetes. For people with both diseases, the risk of heart attack and stroke is higher than for those without them.
The reported increase in diabetes in Australia is thought to be associated with more people being physically inactive, unhealthy eating habits and being overweight. The two main types of diabetes are:
- type 1 – previously known as insulin-dependent or juvenile-onset diabetes
- type 2 – previously known as non-insulin-dependent or mature-onset diabetes.
If you have diabetes, manage your condition by being physically active, choosing healthy foods and maintaining a healthy weight. You may also need to take medicines to maintain normal blood-glucose levels, as well as making lifestyle changes such as quitting smoking. Manage your health by reducing total cholesterol, monitoring blood pressure and regularly seeing your doctor for diabetes reviews.
Being overweight and cardiovascular disease risk
Being overweight or obese increases your risk of a number of health problems, including:
Carrying extra weight around your middle (being ‘apple-shaped’) is more of a health risk, so it is especially important for you to lose weight if this is the case.
To achieve a healthy body weight, balance the energy (kilojoules) coming into your body through food and drinks, with the energy (kilojoules) being used up by your body through regular physical activity.
Healthy eating and cardiovascular disease risk
Eating a variety of foods is good for our health and can help reduce the risk of disease, including heart disease. This helps maintain a healthy and interesting diet and provides a range of different nutrients to the body.
To reduce your heart disease risk, follow these heart healthy eating patterns recommended by the Heart Foundation:
Physical activity and cardiovascular disease risk
Physical activity is an important part of looking after your health and reducing your risk of CVD. Regular physical activity will:
- improve your long-term health
- reduce your risk of heart attack
- give you more energy
- help you to manage your weight
- help you to achieve healthier total cholesterol
- lower your blood pressure
- make your bones and muscles stronger
- make you feel more confident, happy and relaxed
- help you to sleep better.
If you have had a heart attack, regular physical activity will help you to recover more quickly. If you have diabetes, it will also help you to manage your blood-glucose levels.
Physical activity doesn’t have to be strenuous. Moderate-intensity physical activity, such as brisk walking, is great for your health. It is recommended that you do 30–45 minutes of moderate-intensity physical activity on most, if not all, days of the week. You can do this in smaller bouts, such as three 10-minute walks, if it is easier.
Walking for heart health
Try walking to stay active. The Heart Foundation has community walking groups all over Australia you can join. Walking for an average of 30 minutes or more a day can:
- Lower our risk of heart disease, stroke (by 35%) and type 2 diabetes (by 40%)
- Manage weight, blood pressure and cholesterol
- Reduce our risk of some cancers
- Maintain bone density – reducing risk of osteoporosis and fractures
- Improve balance and coordination – reducing your risk of falls and other injuries.
Depression and cardiovascular disease risk
Studies have shown that people with depression, those who are socially isolated or do not have quality social support are at greater risk of developing CVD.
Depression can be treated with medical and non-medical therapies. If you think you have depression, talking to your health professional is the best first step.
Family history and cardiovascular disease risk
A person’s family history of disease (their genes) can increase their tendency to develop:
- high blood pressure
- high cholesterol
- a particular body shape
Although having a family history of CVD is a risk factor you can’t change, it does not mean that you will develop it. However, if you do have a family history of CVD, it is important to reduce or remove other risk factors. For example, adopting healthy eating patterns, do not smoke, and lead an active, healthy lifestyle.
Gender, age and cardiovascular disease risk
Generally, men have a higher risk than women of developing CVD in middle age. The risk rises as they get older.
However, the risk of developing CVD is an important issue for women, especially as they get older. It is not clear why women tend to get CVD at a later age than men, although it is likely that hormonal changes after menopause, combined with changes in their risk factors, play a role.
Despite your gender and age, you can reduce your risk of developing CVD if you follow a healthy lifestyle and take medicines as prescribed by your doctor.
Where to get help