Chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD), also known as chronic obstructive lung disease (COLD), and chronic obstructive airway disease (COAD), is a collection of diseases which make breathing gradually more difficult.

Chronic obstructive pulmonary disease
Other names	Chronic obstructive lung disease (COLD), chronic obstructive airway disease (COAD)
Section of a lung showing centrilobular emphysema, with enlarged airspaces in the centre of a lobule usually caused by smoking and a major feature of COPD
Medical specialty	Pulmonology
Symptoms	Shortness of breath, chronic cough[1]
Complications	Anxiety, depression, pulmonary heart disease, pneumothorax[2][1]
Usual onset	Over 35 years old[1]
Duration	Long term[1]
Causes	Tobacco smoking, air pollution, genetics[3]
Diagnostic method	Spirometry[4]
Differential diagnosis	Asthma, congestive heart failure, bronchiectasis, tuberculosis, obliterative bronchiolitis, diffuse panbronchiolitis[5]
Prevention	Stopping smoking, improving indoor and outdoor air quality, tobacco control measures[3][6]
Treatment	Pulmonary rehabilitation, long-term oxygen therapy, lung volume reduction,[6]
Medication	Inhaled bronchodilators and steroids[6]
Frequency	174.5 million (2015)[7]
Deaths	3.2 million (2019)[3]

Symptoms of COPD include difficulty breathing and cough, in particular coughing up lots of phlegm.^[8] It is usually caused by smoking cigarettes, and around half of people who smoke for their whole lives will develop COPD.^[9] Air pollution can be another cause, particularly in countries where indoor fires are used without ventilation.

At the beginning of the disease, the difficulty breathing is only noticeable when exercising, but over many years it gradually becomes worse, until there is difficulty breathing even when sitting or lying down.^[10] It can also lead to infections of the lung, which may be serious enough to cause death.

The most important step in preventing COPD or its progression into a worse illness is to stop smoking.^[11] Exercise and medications can also help. The most commonly used medications are called bronchodilators, which help to open up the airways and allow more air into the lungs.^[11]

3% of all disability is related to COPD.^[12] Patients with COPD should be screened for mental depression or low mood. Chronic obstructive pulmonary disease were the third most common cause of death globally in 2019.^[13] It is thought that more people will die from it in the future.

Types of COPD

• Emphysema
• Chronic bronchitis
• Bronchiectasis