PulmonologyChronic obstructive pulmonary disease (COPD)0Chronic obstructive pulmonary disease (COPD) is a group of progressive lung diseases. Mostly, these are emphysema and chronic bronchitis. Most people with COPD have both of these conditions. Emphysema slowly destroys air sacs in your lungs, which interferes with outward air flow. Bronchitis causes inflammation and narrowing of the bronchial tubes, which allows mucus to build up.