What is Chronic Obstructive Pulmonary Disease?

Chronic Obstructive Pulmonary Disease is the third leading cause of death in the U.S. and is what former first lady Barbara Bush suffered from before her death. Dr. Jackie Eghrari Sabet of Family Allergy and Asthma Care in Gaithersburg tells News4 what it is, the cause and symptoms of the disease and how to prevent it.