Causes of cirrhosis

There are many different causes of cirrhosis, but excessive alcohol consumption and hepatitis C infection are the most common causes in the UK.

Alcohol-related cirrhosis

Excessive alcohol consumption is more than 21 units a week for men and 14 for women.

The liver breaks down toxins and poisons, such as alcohol, but too much alcohol can damage the cells of the liver.

If you are a heavy drinker, your chances of developing cirrhosis are increased. However, cirrhosis of the liver is not just a condition that affects people dependent on alcohol (alcoholics). If you are a heavy social drinker, you can also develop cirrhosis.

Alcohol-related cirrhosis usually develops after 10 or more years of heavy drinking. Some people are more susceptible to liver cell damage than others, although the reasons for this are unknown.

Women who drink heavily are more susceptible to liver damage than men, partly because of their different body size and build.

Almost all excessive drinkers will develop the first stage of alcoholic liver disease, known as ‘fatty liver’. This is a side effect of the liver breaking down alcohol into carbon dioxide and water. It disappears when you stop drinking to excess.

For people who continue drinking heavily, 20-30% will develop the next stage of alcoholic liver disease: alcoholic hepatitis. At this stage, the liver becomes inflamed and, in its most extreme form, you can die of liver failure.

Around 10% of heavy drinkers then develop cirrhosis, which is the third stage of alcoholic liver disease.

This risk of cirrhosis, along with the risk of alcoholic hepatitis, is one of the main reasons the government recommends that men should not regularly drink more than three to four units a day and women should not regularly drink more than two to three units a day.

Hepatitis-related cirrhosis

Hepatitis C is a bloodborne infection that can cause damage to the liver which, over time, may develop into cirrhosis. It is caused by the hepatitis C virus and is one of the most common causes of cirrhosis in the UK.

Other forms of the infection, hepatitis B and D, can also cause cirrhosis.

Non-alcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH) is a severe liver condition that can lead to cirrhosis. As with alcoholic liver disease, the early stage of NASH is the build-up of excess fat in the liver. This fat is associated with inflammation and scarring, which may progress to cirrhosis.

NASH can occur in people with obesity, diabetes, high levels of fat in the blood and high blood pressure. Most people with NASH feel well and are not aware they have a problem.

Other causes

A number of other conditions and inherited diseases that prevent healthy liver function can also lead to cirrhosis. For example:

  • Autoimmune hepatitis - normally, the immune system makes antibodies to attack bacteria and viruses. However, if you have an autoimmune disease, such as autoimmune hepatitis, your immune system will make antibodies which attack healthy organs of the body, such as the liver.
  • Some rare, genetic conditions such as haemochromatosis (a build up of iron in the liver and other parts of the body), and Wilson's disease (a build up of copper in the liver and other parts of the body).
  • Any condition that causes the bile ducts to become blocked, such as cancer of the bile ducts or cancer of the pancreas.
  • Budd-Chiari syndrome, which is caused by blood clots blocking the veins carrying blood from the liver.

The use of certain drugs and exposure to certain environmental poisons and toxins can also cause cirrhosis.

Last updated: 04 October 2011

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