CAUSES

Prolonged exposure to irritants that damage the lungs and respiratory tract is usually the cause of COPD.

In the United States, the most common irritant that causes COPD is cigarette smoke. Pipe smoke, cigar and other types of tobacco can also cause COPD if the smoke is breathed.

Breathing second-hand smoke, which is smoke from other smokers that is in the air, air contaminated by pollution, chemical vapors or dust from the environment or from the workplace can also contribute to COPD.

Rarely, a genetic disorder called alpha-1-antitrypsin deficiency may play an important role in the causes of COPD. People suffering from this disease have low blood concentrations of alpha-1-antitrypsin (AAT), a protein that is produced in the liver. Low concentrations of the AAT protein can cause lung damage and COPD if the person is exposed to smoke or other lung irritants. If a person has alpha-1-antitrypsin deficiency and also smokes, COPD can get worse very quickly.

Some people with asthma may have COPD. Asthma is a chronic disease of the lungs that causes inflammation and narrowing of the airways. Usually, treatment can reverse the inflammation and narrowing that occurs in asthma.