The Epidemiology, Etiology, Clinical Features, and Natural History of Emphysema

This article presents the epidemiology, etiology, clinical features and natural history of emphysema. Emphysema is defined as abnormal, permanent enlargement of air spaces distal to the terminal bronchioles, accompanied by the destruction of their walls and without obvious fibrosis. This destruction results in the loss of acinar structure, and a subsequent reduction in the area available for gas exchange. The associated loss of elastic tissue leads to small airway collapse and the gas trapping that is often a prominent feature of the disease. The burden of disease attributable to emphysema is significant and growing, and is a leading cause of disability in middle and late life.