Chronic lung disease or chronic obstructive pulmonary disease (COPD) is an incurable illness that makes it very difficult to breathe. COPD is caused when the airways and air sacs become damaged. For people that have healthy lungs, both the airways and air sacs of the lung are springy and elastic. For people with COPD, the airways and air sacs lose their shape and become floppy, like a stretched-out rubber band.  

Examples of diseases that cause COPD include:

• Bronchitis

Bronchitis is an inflammation of the main air passages (bronchi) of the lungs. Inflamed bronchi produce excessive mucus, which leads to a cough and difficulty getting air in and out of the lungs. Chronic bronchitis is commonly caused by cigarette smoking, or breathing in fumes and dusts over a long period of time.  

• Emphysema 

Emphysema is a type of COPD where there is damage to the air sacs (alveoli) in the lungs. As a result of the damaged air sacs, the body does not get the oxygen it needs. Emphysema is commonly caused by cigarette smoking. 

COPD hospital admission is not a measure of hospital quality, but rather one way to measure outpatient care for COPD. Proper outpatient treatment for COPD may decrease the likelihood of hospital admission for COPD.