Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease that causes obstructed airflow from the lungs. It is caused by long-term exposure to irritating gases or particulate matter from pollution such as cigarette smoke. In India, besides cigarette smoke, air pollution and other environmental risk factors are also a leading cause of COPD. People with COPD are at increased risk of developing heart disease, lung cancer and a variety of other conditions.