Risk Factors and Causes


Dr. Green
Chronic obstructive pulmonary disease, or COPD, is usually caused by long-term exposure to lung irritants that damage the bronchial tree and alveoli. Dr. Mansfield, can you tell us more?

Dr. Mansfield
Certainly, Dr. Green. The most common irritant that causes COPD in the United States is cigarette smoke. In fact, it's estimated that between 75 and 90 percent of people who have COPD in the U.S. have a history of smoking. Pipe, cigar, and other types of tobacco smoke can also cause COPD, especially if the smoke is inhaled. In undeveloped countries, COPD can be caused by smoke from burning wood or other vegetation used for cooking.

Other irritants that can cause COPD include:

  • Secondhand smoke
  • Air pollution, and
  • Chemical fumes or dusts found in work environments

In rare cases, COPD can be linked to a genetic condition called alpha-1 antitrypsin, or AAT, deficiency. People with this condition have low blood levels of AAT which is a protein made in the liver. Without the AAT protein, white blood cells begin to attack and damage the lungs.