What causes COPD?
COPD is often caused by smoking. Most people with COPD have smoked for a long time. Over time, breathing tobacco smoke irritates the airways and damages the lungs.
Air pollution also causes COPD. Other things that may lead to COPD include breathing chemical fumes, factory dust, soot, and secondhand smoke over a long period of time.
People who get emphysema at a young age, such as in their 30s or 40s, may have a disorder that runs in families, called alpha-1 antitrypsin deficiency. This is a condition in which your body may not be able to make enough of a protein (alpha-1 antitrypsin) that helps protect the lungs from damage.