E cigarette use increases risk for developing major respiratory diseases COPD is a progressive, largely irreversible airflow limitation characterized by chronic cough, sputum production, and dyspneamost commonly due to smoking. Spirometry (FEV FVC < 0.7) confirms diagnosis; smoking cessation is the most effective COPD Resources Chronic Obstructive Pulmonary Disease The Troubling Truth About COPD and Vaping University of Maryland Medical System Health Hub COPD (Emphysema and Chronic Bronchitis): From Diagnosis to Treatment Manual of Medicine