Exercise is medicine. Nowhere is this more true than in the area of coronary heart disease (CHD). The positive effects of regular exercise on moderating CHD risk are manyfold. Before we examine exactly how exercise can be beneficial (covered in the next blog) the focus of this article is to investigate and explain what CHD is and how it develops. Let’s first take a look at some of the facts and figures related to the incidence of disease.
The prevalence of coronary heart disease in the UK
Cardiovascular diseases are the UK’s biggest health problem. According to the British Heart Foundation:
- Heart and circulatory diseases cause a quarter of all deaths in the UK, that’s more than 160,000 deaths each year.
- There are around 7.6 million people living with a heart or circulatory disease in the UK: 4 million men and 3.6 million women.
- Coronary heart disease is the most common type of heart disease. It is the most common cause of heart attack and was the single biggest killer of both men and women worldwide in 2019.
- In the UK there are around 100,000 hospital admissions each year due to heart attacks; that’s one every five minutes.
- Around 1.4 million people alive in the UK today have survived a heart attack.
- More than 900,000 people in the UK are living with heart failure.
- Strokes cause around 34,000 deaths in the UK each year and are the biggest cause of severe disability in the UK.
The definition and development of coronary heart disease
Coronary heart disease develops as a result of the progression of a condition known as atherosclerosis. This is a narrowing of the arteries that supply blood and oxygen to the heart muscle itself. Many years ago atherosclerosis was thought to be a disease that was only caused by aging. However, more recent research findings have shown that when younger victims of accidental deaths have been autopsied they have also exhibited the signs of atherosclerosis. This includes car crash victims as young as six years old.
Take a few brief minutes to watch this video for a straightforward explanation of how atherosclerosis develops.
As you will have seen in the video, atherosclerotic plaques can start to develop when the inner lining of the coronary artery becomes damaged. This lining is known as the endothelial layer. It is very thin, and is sensitive to damage by high blood pressure and inflammatory particles, which can be present as a result of; smoking, stress, poor diet, drinking alcohol, being overweight, and being physically inactive. (Click here for my article explaining chronic inflammation)
Once the inner lining of the coronary arteries has been damaged, substances in the blood, particularly cholesterol starts to become stuck in the damaged areas. When these substances accumulate a plaque develops and grows.
The plaque itself will narrow the arteries and restrict blood flow when this happens in the coronary arteries, a person can start to suffer chest pains from a condition known as angina. If the plaque were to break or burst a blood clot can form on the outside of the plaque and completely block the coronary artery. When this happens the heart muscle that the artery supplies blood to will be deprived of oxygen and it may die. This is known as a heart attack or myocardial infarction.
Having explained the two main phases of the development of CHD, it should be helpful to now summarise what all of the risk factors are.
What are the coronary heart disease risk factors?
There are many factors which determine whether or not someone will develop CHD. Some of these are non-modifiable, such as:
- A family history of CHD (especially high blood cholesterol levels)
- Ethnic background
However, there are other risk factors, known as lifestyle factors, which are modifiable. They are:
- Being physically inactive
- Being overweight
- Having high blood pressure
- Having high blood cholesterol
- Having diabetes
- Drinking alcohol
- Being stressed
It is these nonmodifiable, lifestyle factors that we should therefore focus upon when we think about how we can reduce our risk of developing CHD. Regular exercise has a huge role to play, as you will see in the next blog post.