Chronic Obstructive Pulmonary Disease (COPD) is a medical term used to describe progressive lung diseases. The diseases that fall under this umbrella term include chronic bronchitis, emphysema, non-reversible asthma, and certain forms of bronchiectasis.
The main symptom of COPD is increased breathlessness. According to the American Lung Association, COPD is the third leading cause of death in the United States. There have been over 11 million people diagnosed with COPD and many more have it, they just don't know it yet. This is because these people believe that their increased breathlessness is a normal part of aging.