Chronic obstructive pulmonary disease Health Article

Definition

Chronic obstructive pulmonary disease (COPD) is one of the most common lung diseases. It makes it difficult to breathe. There are two main forms of COPD:

• Chronic bronchitis, defined by a long-term cough with mucus
• Emphysema, defined by destruction of the lungs over time

Most people with COPD have a combination of both conditions.

Alternative Names

COPD; Chronic obstructive airways disease; Chronic obstructive lung disease; Chronic bronchitis; Emphysema; Bronchitis - chronic

Causes, incidence, and risk factors

Smoking is the leading cause of COPD. The more a person smokes, the more likely that person will develop COPD although some people smoke for years and never get COPD.

In rare cases, nonsmokers who lack a protein called alpha-1 antitrypsin can develop emphysema.

Other risk factors for COPD are:

• Exposure to certain gases or fumes in the workplace
• Exposure to heavy amounts of secondhand smoke and pollution
• Frequent use of cooking gas without proper ventilation

Symptoms

• Cough with mucus
• Shortness of breath (dyspnea) that gets worse with mild activity
• Fatigue
• Frequent respiratory infections
• Wheezing

Since the symptoms of COPD develop slowly, some people may be unaware that they are sick.

Signs and tests

The best test for COPD is a simple lung function test called spirometry. This involves blowing out as hard as one can into a small machine that tests lung capacity. The test can be interpreted immediately and does not involve exercising, drawing blood, or exposure to radiation.

Using a stethoscope to listen to the lungs can also be helpful, although sometimes the lungs sound normal even when COPD is present.

Pictures of the lungs (such as X-rays and CT scans) can be helpful but sometimes look normal even when a person has COPD.

Sometimes it is necessary to do a blood test (call a “blood gas”) to measure the amounts of oxygen and carbon dioxide in the blood.