What Is Chronic Obstructive Pulmonary Disease?

Chronic obstructive pulmonary disease (COPD), also called chronic obstructive lung disease, is a term that is used for two closely related diseases of the respiratory system: chronic bronchitis and emphysema. In many patients these diseases occur together, although there may be more symptoms of one than the other. Most patients with these diseases have a long history of heavy cigarette smoking.

Cigarette smoking is the most important risk factor for COPD.

COPD gets gradually worse over time. At first there may be only a mild shortness of breath and occasional coughing. Then a chronic cough develops with clear, colorless sputum. As the disease progresses, the cough becomes more frequent and more and more effort is needed to get air into and out of the lungs. In later stages of the disease, the heart may be affected. Eventually death occurs when the function of the lungs and heart is no longer adequate to deliver oxygen to the body's organs and tissues.

Cigarette smoking is the most important risk factor for COPD; it would probably be a minor health problem if people did not smoke. Other risk factors include age, heredity, exposure to air pollution at work and in the environment, and a history of childhood respiratory infections. Living in low socioeconomic conditions also seems to be a contributing factor.