Chronic obstructive pulmonary disease (COPD)Causes

Chronic obstructive pulmonary disease (COPD) occurs when the lungs and airways become damaged and inflamed.

It's usually associated with long-term exposure to harmful substances such as cigarette smoke.

Things that can increase your risk of developing COPD are outlined below.

Smoking

Smoking is the main cause of COPD and is thought to be responsible for around 9 in every 10 cases.

The harmful chemicals in smoke can damage the lining of the lungs and airways. Stopping smoking can help stop COPD getting worse.

Some research has also suggested that being exposed to other people's smoke (passive smoking) may increase your risk of COPD.

Fumes and dust at work

Exposure to certain types of dust and chemicals at work may damage the lungs and increase your risk of COPD.

Substances that have been linked to COPD include:

• cadmium dust and fumes
• grain and flour dust
• silica dust
• welding fumes
• isocyanates
• coal dust

The risk of COPD is even higher if you breathe in dust or fumes in the workplace and you smoke.

The Health and Safety Executive has more information about occupational causes of COPD.

Air pollution

Exposure to air pollution over a long period can affect how well the lungs work and some research has suggested it could increase your risk of COPD.

But at the moment the link between air pollution and COPD isn't conclusive and research is continuing.

Genetics

You're more likely to develop COPD if you smoke and have a close relative with the condition, suggesting some people's genes may make them more vulnerable to the condition.

Around 1 in 100 people with COPD has a genetic tendency to develop COPD called alpha-1-antitrypsin deficiency. Alpha-1-antitrypsin is a substance that protects your lungs. Without it, the lungs are more vulnerable to damage.

People who have an alpha-1-antitrypsin deficiency usually develop COPD at a younger age, often under 35 – particularly if they smoke.

The British Lung Foundation has information about alpha-1-antitrypsin deficiency. The charity Alpha-1 Awareness UK also provides information and advice.