What is COPD?
COPD stands for chronic obstructive pulmonary (lung) disease. COPD is a general term used for several lung diseases. The most common diseases in this group are chronic bronchitis and emphysema. Chronic asthma may also be included in this group. While some patients with COPD have only chronic bronchitis or emphysema, most patients have a combination of both. COPD worsens gradually, causing limited airflow in and out of the lungs.
COPD adds to the work of the heart. Diseased lungs may reduce the amount of oxygen that goes to the blood. High blood pressure in blood vessels from the heart to the lungs makes it difficult for the heart to pump. Lung disease can also cause the body to produce too many red blood cells which may make the blood thicker and harder to pump.
Patients who have COPD with low oxygen levels may develop an enlarged heart (cor pulmonale). This condition weakens the heart and causes increased shortness of breath and swelling in the legs and feet.
Chronic bronchitis
Chronic bronchitis is irritation and inflammation (swelling) of the lining in the bronchial tubes (air passages). The irritation causes coughing and an excess amount of mucus in the airways. The swelling makes it difficult to get air in and out of the lungs. The small, hair-like structures on the inside of the airways (called cilia) may be damaged by the irritation. The cilia are then unable to help clean mucus from the airways.
Bronchitis is generally considered to be chronic when you have: a productive cough (cough up mucus) and shortness of breath that lasts about 3 months or more each year for 2 or more years in a row. Your doctor may define chronic bronchitis differently.
Emphysema
Emphysema is the destruction, or breakdown, of the walls of the alveoli (air sacs) located at the end of the bronchial tubes. The damaged alveoli are not able to exchange oxygen and carbon dioxide between the lungs and the blood. The bronchioles lose their elasticity and collapse when you exhale, trapping air in the lungs. The trapped air keeps fresh air and oxygen from entering the lungs.
Who is affected by COPD?
Emphysema and chronic bronchitis affect approximately 16 million people in the United States, or close to 11 percent of the population.
Symptoms of COPD
- Shortness of breath
- Shortness of breath with mild exercise (walking, using the stairs, etc.)
- Chronic, productive cough (with mucus)
- A feeling of "tightness" in the chest
- Wheezing
What causes COPD?
The two primary causes of COPD are cigarette smoking and alpha1-antitrypsin (AAT) deficiency. Air pollution and occupational dusts may also contribute to COPD, especially when the person exposed to these substances is a cigarette smoker.
Cigarette smoke causes COPD by irritating the airways and creating inflammation that narrows the airways, making it more difficult to breathe. Cigarette smoke also causes the cilia to stop working properly so mucus and trapped particles are not cleaned from the airways. As a result, chronic cough and excess mucus production develop, leading to chronic bronchitis.
In some people, chronic bronchitis and infections can lead to destruction of the small airways, or emphysema.
AAT deficiency, an inherited disorder, can also lead to emphysema. Alpha antitrypsin (AAT) is a protective material produced in the liver and transported to the lungs to help combat inflammation. When there is not enough of the chemical AAT, the body is no longer protected from an enzyme in the white blood cells. This can cause a breakdown in the walls of the air sacs (alveoli). When the alveoli are destroyed, oxygen cannot be transferred into the blood and carbon dioxide cannot be taken from the blood to be exhaled.
How is COPD diagnosed?
Medical history
To diagnose COPD, the physician needs to know:
- Do you smoke?
- Have you had chronic exposure to dust or air pollutants?
- Do other members of your family have lung disease?
- Are you short of breath?
- Do you get short of breath with exercise?
- Do you have chronic cough and/or wheezing?
- Do you cough up excess mucus?
Physical exam
To help with the diagnosis, the physician will conduct a thorough physical exam which includes:
- Listening to your lungs and heart
- Checking your blood pressure and pulse
- Examining your nose and throat
- Checking your feet and ankles for swelling
Laboratory and other tests
Several laboratory and other tests are needed to confirm a diagnosis of COPD. These tests may include:
- Electrocardiogram (ECG or EKG) to check heart function and rule out heart disease as a cause of shortness of breath
- Chest X-ray to look for lung changes that could be caused by COPD
- Spirometry and pulmonary function tests (PFTs) to determine lung volume and air flow
- Pulse oximetry to measure the saturation of oxygen in the blood
- Arterial blood gases (ABGs) to determine the amount of oxygen and carbon dioxide in the blood
- Exercise testing to determine if the oxygen level in the blood drops during exercise
Treatment
In the beginning stages of COPD, there is minimal shortness of breath that may be noticed only during exercise. As the disease progresses, shortness of breath may worsen and you may need to wear an oxygen device.
To help control other symptoms of COPD, the following treatments and lifestyle changes may be prescribed.
- Quitting smoking
- Avoiding cigarette smoke and other irritants
- Taking medications including:
- bronchodilators
- anti-inflammatory agents
- oxygen
- antibiotics
- Maintaining a healthy diet
- Following a structured exercise program
- Preventing respiratory infections
- Controlling stress
If your COPD progresses, you may be eligible to be evaluated for lung volume reduction surgery or lung transplantation.
You may also be eligible to participate in certain clinical trials (research studies). Ask your health care providers about studies being conducted in your hospital.
What is the outlook?
Although COPD can not be cured, its symptoms can be treated and your quality of life can be improved. Your prognosis or outlook for the future will depend on how well your lungs are functioning, your symptoms, and how well you respond to and follow your treatment plan.
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 11/22/2005
