Chronic obstructive pulmonary disease (COPD) is considered a very dangerous illness, affecting over thirty two million people in the United States. It has a high mortality rate and is considered the third leading cause of death in the United States. Patients suffering from COPD usually have symptoms of damaged alveoli which impairs exchange of gas, chronic bronchitis or severe mucus secretion which blocks airways and asthma or inflamed airways obstructing the flow of air.
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