COPD (chronic obstructive pulmonary disease) is a disease in which the lung is damaged, making it hard to breathe. Cigarette smoking is the most common cause, as is long-term exposure to other kinds of irritants, such as pollution or chemicals. There is no cure for this disease, and the damage to your lungs cannot be reversed. However, treatment can help with breathing and minimize the damage to your lungs.
What Is COPD?
Chronic obstructive pulmonary disease (COPD) is a lung disease in which the lung is damaged, making it difficult to breathe. In COPD, the airways (the tubes that carry air in and out of your lungs) are partly obstructed, making it difficult to get air in and out.
COPD is a major cause of death and illness throughout the world. It is the fourth leading cause of death in the United States and the world.
COPD and the Airways
The airways branch out like an inverted tree, and at the end of each branch are many small, balloon-like air sacs. In healthy people, each airway is clear and open, the air sacs are small and dainty, and both are elastic and springy. When you breathe in, each air sac fills up with air, like a small balloon, and when you breathe out, the balloon deflates and the air goes out (see Lung Anatomy).
In COPD, the airways and air sacs lose their shape and become floppy. Less air gets in and less air goes out because:
- The airways and air sacs lose their elasticity (like an old rubber band)
- The walls between many of the air sacs are destroyed
- The walls of the airways become thick and inflamed (swollen)
- Cells in the airways make more mucus (sputum) than usual, which tends to clog the airways.
COPD develops slowly, and it may be many years before you notice symptoms, such as feeling short of breath. Most of the time, COPD is diagnosed in middle-aged or older people.