Shortness of Breath (Dyspnea)

Dyspnea, the most common symptom of COPD, comes on gradually and is first noticed during physical exertion or during acute exacerbations. It usually begins when patients are in their 60s and 70s and slowly becomes more prominent. It is closely associated with lung function decline and is not always associated with low oxygen in the blood.

Patients often wonder why dyspnea occurs so long after beginning to smoke, say 50 to 60 years later. Some patients have even quit smoking several years before symptoms appear. The main reason is that lung function declines slowly with age, even in a nonsmoker. At approximately age 30, people begin to lose lung function at a rate of 25 to 30 mL/year of forced expiratory volume in 1 second (FEV1; see Spirometry). People who smoke lose lung function at a more rapid rate, approximately 125 mL/year. Because the lungs have a considerable amount of reserve, a large portion must become nonfunctional before symptoms occur. It can take more than 30 years to lose enough lung function to experience symptoms.

When a person quits smoking, the loss in function slows to approximately the rate of a nonsmoker. If smoking has already destroyed a large portion of the lungs, the threshold will be reached, eventually, at a rate of decline of 30 mL/year instead of 125 mL/year. Without quitting, decline would continue at a rate of 125 mL/year. Quality of life can improve by quitting, even if lung function has already declined.

Chronic Cough

Chronic cough typically begins as a morning cough and slowly progresses to an all-day cough. The cough usually produces small amounts of sputum (less than 60 mL/day) and is clear or whitish but may be discolored. Sputum production decreases when one quits smoking.

The progression of the cough's frequency is so slow that a person usually tolerates it for a couple of years before seeing a doctor. Any change in a chronic cough or a new cough in a smoker or patient with COPD should be thoroughly evaluated by a physician.


Wheezing is the high-pitched sound of air passing through narrowed airways. A person with COPD may wheeze during an acute exacerbation or chronically. Sometimes the wheezing is heard only at night or with exertion. Bronchodilators can relieve wheezing quickly (see Bronchodilators).


COPD is one of the more common causes of hemoptysis (coughing up blood). It usually occurs during an acute exacerbation, when there is a lot of coughing with purulent sputum (sputum containing pus). Usually, there are only very small amounts of blood streaking the sputum. Hemoptysis may be a sign of lung cancer in a patient with COPD, so any blood appearing in the sputum should be brought to a doctor's attention.

Weight Loss

Patients with severe COPD work hard and burn a lot of calories just breathing. These patients also become short of breath in the very act of eating, and so may not eat enough to replace the calories they use.

Lower Extremity Edema

In severe cases of COPD, pulmonary artery pressures increase and the right ventricle of the heart contracts less efficiently. When the heart is unable to pump enough blood to meet the needs of the kidneys and liver, edema (swelling) in the feet, ankles, and lower legs results. It can also cause the liver to become swollen and tender or fluid to accumulate in the abdomen (ascites). A distended abdomen can be a sign of ascites.

Publication Review By: Stanley J. Swierzewski, III, M.D.; the Editorial Staff at

Published: 31 May 2000

Last Modified: 10 Sep 2015