Atherosclerosis is a potentially serious condition where arteries become clogged up by fatty substances known as plaques or atheroma.

The plaques cause affected arteries to harden and narrow, which can be dangerous as restricted blood flow can damage organs and stop them functioning properly.

If a plaque ruptures, it can cause a blood clot. This can block the blood supply to the heart, triggering a heart attack, or it can block the blood supply to the brain, triggering a stroke.

Cardiovascular disease (CVD)

Atherosclerosis is a major risk factor for many conditions involving the flow of blood.

Collectively, these conditions are known as cardiovascular disease (CVD). Examples include:

  • peripheral arterial disease – where the blood supply to your legs is blocked, causing muscle pain
  • coronary heart disease – the coronary arteries (the main arteries that supply your heart) become clogged with plaques
  • stroke – where the blood supply to your brain is interrupted
  • heart attack – where the blood supply to your heart is blocked

Read more about atherosclerosis and cardiovascular disease.

What causes atherosclerosis?

Exactly how arteries become clogged is still unclear, although the following things increase your risk of atherosclerosis:

Read more about causes and risk factors for atherosclerosis.

Treating atherosclerosis

Treatment for atherosclerosis aims to prevent the condition from worsening to the point that it can trigger a serious cardiovascular disease, such as a heart attack.

This can be achieved by making lifestyle changes, such as eating a healthier diet and increasing exercise, as well as using certain medications such as ACE inhibitors to treat high blood pressure, or statins to lower cholesterol levels.

In some cases, surgery may be required to widen or bypass a section of a blocked or narrowed artery.

Read more about the treatment of atherosclerosis.

Who is affected?

It is hard to estimate how common atherosclerosis is, although it is suspected that almost all adults have the condition to some degree.

Your arteries naturally get harder as you grow older, so atherosclerosis tends to be more common in people aged over 40.

Atherosclerosis is more common in men than women, possibly because hormones used in the female reproductive cycle, such as oestrogen, provide some protection against the effects of the condition.

The public health impact of atherosclerosis

Atherosclerosis (and the resulting cardiovascular diseases) is the single biggest cause of death in the developed world, accounting for one in three of all deaths.

Each year an estimated 124,000 deaths are caused by cardiovascular disease in England and Wales. Around 39,000 of these deaths occur in people under 75 years. 

For every death, cardiovascular disease causes two non-fatal but serious complications, such as a stroke or heart attack.

It is expected that atherosclerosis will continue to be a major health problem in this country because of the ongoing obesity epidemic.  

The arteries

Blood is pumped from the heart through the aorta (the main artery leading from the heart) before travelling through increasingly small arteries that branch off from each other.

The blood passes into tiny blood vessels (capillaries), where the oxygen in the blood is transferred into the cells of the tissues and organs. The blood then returns to the heart through the veins.

Two important arteries are:

  • coronary arteries – which provide blood to the heart
  • carotid arteries – which supply blood to the brain

If a blood clot occurs in the coronary artery, it can trigger a heart attack. A blood clot in the carotid artery can trigger a stroke.

Page last reviewed: 13/06/2014

Next review due: 13/06/2016