Chronic Obstructive Pulmonary Disease Chronic Obstructive Pulmonary Disease (COPD) is a slow progressing destruction of airways caused by gradual loss of lung function. It’s a combination of various lung diseases. In COPD, two lung diseases, namely chronic bronchitis and emphysema are the main diseases. Other diseases like asthmatic bronchitis and bullous disease are also present. This disease is common among the older women in America. On a whole, about 11% of the American population suffers from COPD. According to researches, it kills 85,000 people in the US every year and it is the fourth leading cause of death.