Association of electronic cigarette use and risk of COPD: a systematic review and meta analysis npj Primary Care Respiratory Medicine Vaping Nicotine Impairs Airway Clearance RT COPD: The Differences Between Emphysema and Bronchitis Affordable Portable Oxygen Concentrators 1st Class Medical E Cigarette or Vaping Product Use Associated Lung Injury: A Comprehensive Review Can E cigarettes help COPD patients quit smoking and reduce harm to lungs? 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