Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease that causes obstructed airflow flow from the lungs. Symptoms include respiratory problem, cough, sputum production and wheezing. The cause of COPD is usually long term exposure to gases that damage your lungs and airways. Other causes include infectious diseases, air pollution, and genetic conditions. The foremost common of those diseases are emphysema- slowly destroys air sacs in your lungs that interfere with outward air flow and bronchitis causes inflammation and narrowing of the bronchial tubes that permits sputum to build up.