By Credentialled Diabetes Educator, Carolien Koreneff

Did you know that people with type 2 diabetes are two to four times more likely to develop heart disease? Yet research shows that only 12% of people with type 2 diabetes think they are personally at risk. The connection between diabetes and heart disease is closer than many people realise.

People with type 1 diabetes are also at increased risk of heart disease.

Knowing that your heart could be affected by diabetes is the first step to reducing your risk.

What is heart disease?

Heart disease is a collective term for different problems that affect the structure and function of the heart muscle. It includes coronary artery disease, heart failure, arrhythmias and valve disease.

The medical term cardiovascular disease includes all types of heart problems, as well as blood vessel damage and stroke. The most common type of cardiovascular disease is coronary artery disease.

Coronary artery disease

Coronary artery disease (CAD) is very common and is caused by a build-up of plaque in the arteries, the blood vessels that supply blood and oxygen to the heart. Plaque is the build-up of fats and other substances in the artery walls. This build-up of plaque can cause a narrowing or complete blockage of blood vessels, which affects the blood flow.

Coronary artery disease is also associated with a hardening of the arteries, this is referred to as atherosclerosis. Hardening of the arteries can also happen in other parts of your body, for example in your feet and legs – this is referred to as peripheral artery disease (PAD).

Coronary artery disease is sometimes also called coronary heart disease (CHD) or ischaemic heart disease (IHD); it usually takes years to develop.

Heart attack

If the blood flow to the heart is decreased it can cause a heart attack. Similarly, if the blood flow to the brain is decreased it can cause a stroke.

Heart attacks happen when the plaque in a blood vessel bursts and clogs the coronary artery. Heart attacks require urgent medical treatment to restore the blood flow to the heart.

It is important to note that heart attacks are different from a cardiac arrest. Heart attacks are a circulatory problem, whereas a cardiac arrest is an electrical problem.

Cardiac arrest

Cardiac arrests are often caused by arrhythmias (abnormal heart rhythms) that cause the heart to malfunction and stop beating. This stops blood from flowing to the brain and other vital organs and can lead to death if not treated urgently.

A person who is having a cardiac arrest will be unconscious, will not be breathing and may die within three minutes unless chest compressions are started immediately and medical care is provided.

Arrythmias

Arrythmias, as mentioned above, are abnormal heart rhythms caused by the heart’s electrical system which controls the heart’s pumping action. People often describe arrythmias as palpitations or fluttering feelings in the chest.

Arrythmias can cause the heartbeat to become too slow, too fast, or irregular. The most common type of arrythmia is atrial fibrillation (AF). Other examples of arrythmias include atrial flutter, ectopic heartbeats, and supraventricular tachycardia (SVT).

Heart failure

Heart failure happens when the heart muscle is damaged and does not pump properly. Causes can include heart attacks, high blood pressure and valve problems, which can all lead to the heart becoming weaker, stiffer and bigger. This can lead to tiredness, shortness of breath, oedema (swelling in legs and feet) and a decreased ability to do physical activity. Treatment involves medications to strengthen the heart as well as managing other conditions that can affect the heart.

Valve disease

The four cardiac valves mentioned above keep the blood flowing in the right direction. If one or more of these valves become damaged they may stop opening and closing properly and this can lead to chest pain and shortness of breath. Some people are born with valve disease (this if often called congenital heart disease), but it can also be caused by rheumatic heart disease, acute rheumatic fever or a heart condition such as heart failure or a heart attack.

There are three main types of heart valve disease:

1. Stenosis – where the valves are thick or stiff
2. Regurgitation – where the valve flaps don’t close properly and ‘leak’
3. Atresia – this is a condition where the valve is not formed correctly and tissue blocks the blood flow.

One of the first signs of heart valve problems is a heart murmur, this is an abnormal sound that your doctor can hear when listening to your heartbeat with a stethoscope. However, having a heart murmur does not always mean that there is a problem with your heart. But if you experience symptoms of heart valve disease it is important to see a doctor because, if left untreated, heart valve disease can lead to heart failure.

Diabetes and heart disease

Diabetes puts you at risk of heart disease because diabetes can change the chemical makeup of some of the substances found in the blood. This can cause a narrowing or complete blockage of blood vessels through the build-up of plaque, even if your cholesterol levels are normal.

High blood pressure can put further strain on your heart. For this reason, people with diabetes are regularly recommended to take blood pressure lowering medications, often in combination with cholesterol lowering medication.

What are the symptoms of heart disease?

The most common symptom of heart disease is chest pain or discomfort. This is referred to as angina.

For many people with diabetes the symptoms are very subtle and the first clue that they have coronary artery disease is a heart attack. Symptoms of a heart attack include:

• Angina
• Shortness of breath
• Pain or discomfort in the arms and/or shoulder
• Tingling in the lips
• Weakness
• Light-headedness or dizziness
• Nausea, vomiting or heartburn
• Cold sweat

Sometimes heart disease is not diagnosed until a person experiences arrhythmia or heart failure. Symptoms of heart failure include:

• Shortness of breath
• Fatigue
• Swelling of the feet, ankles, legs or veins in the neck

What are the risk factors for heart disease?

The main risk factors for developing heart disease are high blood pressure, high cholesterol and smoking.

Lifestyle choices can also increase your risk, particularly through an unhealthy diet, excessive alcohol use, physical inactivity and overweight or obesity.

Several other medical conditions can put people at a higher risk as well. You may have guessed it; diabetes is on top of this list.

Having a family history of heart disease can also increase your risk.

Reducing your risk of heart disease

Taking care of your heart is important, especially when you have diabetes. Here are some actions you can take to reduce your risk of heart disease:

• Be physically active
• Make healthy food choices
• Reduce your intake of saturated fats, trans fat, salt/sodium and alcohol
• Keep blood fats such as cholesterol and triglycerides in the target range
• Manage high blood pressure
• Try and lose weight if your weight is above the healthy weight range
• Don’t smoke – if you do smoke try and quit
• Visit Diabetes Australia’s heart-focused campaign takediabetes2heart.com.au.

Take Diabetes 2 Heart Campaign

The Take Diabetes 2 Heart campaign is all about inspiring people with diabetes, and the people who love them, to take positive steps to avoid cardiovascular disease. The three most important steps on the path to good heart health are: visiting your doctor to have a conversation about what you can do to reduce your risk; eating a balanced diet; and incorporating exercise into your daily routine. Visit the website for helpful information, resources and a heart healthy recipe book that you can download for free. 

Blood pressure

As your heart pumps your blood through your arteries, a force or pressure is created as the blood travels; this is known as blood pressure. Your blood pressure will go up and down naturally throughout the day and night, this depends on what you are doing.

High blood pressure, or hypertension, is a main risk for heart disease, especially heart attacks and strokes. High blood pressure can also increase your risk of kidney disease, eye disease and nerve damage.

Many people have high blood pressure without knowing it, so it is important to get your blood pressure checked regularly.

There are a number of things that can increase your risk of developing hypertension, including having a family history of hypertension, being overweight, insufficient physical activity, smoking, alcohol intake and food choices such as eating too much salt.

Blood pressure targets can vary depending on your age, existing heart disease, kidney disease, other medical conditions and your risk of a stroke. In Australia it is generally recommended to aim for a blood pressure of less than 140/90 millimetres of mercury (mmHg).

Cholesterol

Cholesterol is a fatty substance that your body needs to build cells, to make certain hormones and to produce vitamin D. It is also important in digestion of food. Some foods contain cholesterol; your body also produces it.

When your doctor orders a cholesterol check the pathologist will check and report on the following types of blood fat:

• Total cholesterol – a calculation of all the different types of cholesterol in your blood
• Low-density lipoprotein (LDL) – ‘bad’ or ‘lousy’ cholesterol, because it sticks to the walls of arteries and cause plaque.
• High-density lipoprotein (HDL) – ‘good’ or ‘healthy’ cholesterol, because it carries LDL away from the arteries, back to the liver where it is broken down.
• Triglycerides – the most common fat in the body that will increase when eating a lot of high fat and sugary foods, when drinking too much alcohol, or if you are overweight.

There is not one single cause of high cholesterol, but there are risk factors that are modifiable. These include smoking, your age, being overweight or obese, having a family history, and unfavourable lifestyle choices such as an unhealthy diet and a lack of physical activity.

If you experience any symptoms of a heart attack it is important to get medical help immediately. Call 000 without delay.