Emphysema vs. COPD differences, symptoms, treatments, and more What is COPD? First Aid for Free Electronic cigarette use and its association with asthma, chronic obstructive pulmonary disease (COPD) and asthma COPD overlap syndrome among never cigarette smokers Chronic obstructive pulmonary disease (COPD) is a chronic, progressive lung disorder characterized by persistent airflow limitation that is not fully reversible. It develops gradually, most often due to long term exposure to harmful