What Is It?

Chronic obstructive pulmonary disease (COPD) refers to a group of disorders that damage the lungs and make breathing increasingly more difficult over time. The two most common forms of COPD are chronic bronchitis and emphysema. Both are chronic (long-term) illnesses that impair airflow in the lungs. Currently, COPD affects at least millions of people in the United States, causing more than 100,000 deaths each year. In more than 80% of cases, the illness is related to cigarette smoking.

Chronic Bronchitis In this respiratory disorder, the air passages in the lungs are inflamed, and the mucus-producing glands in the larger air passages of the lungs (bronchi) are enlarged. These enlarged glands produce too much mucus, which triggers a cough. In chronic bronchitis, this cough lasts for at least three months of the year for two consecutive years.

Chronic bronchitis affects about 3% of the people in the United States, most commonly men older than 40. You are more likely to develop chronic bronchitis if you:

• Smoke tobacco

• Are exposed to air pollution

• Are exposed in the workplace to airborne organic dusts or toxic gases, especially in cotton mills and plastic manufacturing plants

• Have a history of frequent respiratory illnesses

• Live with a smoker

• Have an identical twin with chronic bronchitis

Chronic bronchitis may have different symptoms in different people. In milder cases, a cough produces only a small amount of thin, clear mucus. In other people, the mucus is thick and discolored. Symptoms similar to asthma may develop, including wheezing and shortness of breath. Eventually, the airways become narrowed, limiting the amount of oxygen that gets to the air sacs. Blood vessels constrict in an attempt to divert the blood to better-oxygenated areas of the lung. This increases blood pressure in the arteries that feed the lungs, and strains the right side of the heart. Eventually, if blood pressure remains high enough in the lungs, heart failure develops, and blood backs up in the liver, abdomen and legs.