Types of Chronic Obstructive Pulmonary Disease

COPD may be caused by chronic bronchitis or emphysema or a combination of both.
Chronic Bronchitis-Inflammation of the airways and lung damage causes chronic bronchitis. Clinically, a person is diagnosed as having chronic bronchitis if he has cough (with the production of sputum) for two consecutive years. In a given year he should have had the above mentioned symptom for at least three months.

Emphysema-The alveoli is permanently enlarged because the walls between them have been destroyed. This in turn reduces lung elasticity and the support given to the airways reduce.