What is COPD?
What does the term COPD mean? It stands for Chronic Obstructive Pulmonary Disease and refers to a problem with breathing air out from your lungs. If you have difficulty breathing "used" air out of your lungs, not enough space is left for oxygen-rich air to enter your lungs. In order to detect airway obstruction associated with COPD, a simple breathing test called spirometry is required.
Until recently, most people who had COPD were grouped together and considered to have one disease. We now know that several different diseases cause this difficulty in releasing air from the lungs. Asthmatic bronchitis, chronic bronchitis, and emphysema are three of the major diseases that are grouped together as COPD.
Asthmatic and Chronic Bronchitis
Both asthmatic and chronic bronchitis occur when the large airways or bronchi are inflamed and swollen. Imaging what happens to your skin when you've gotten an insect bite and it becomes swollen, red, and painful. This same idea can be applied to the swelling that occurs with bronchitis. The lining of the air tubes becomes swollen and produces large amounts of mucus. Because mucus clogs the airways, it complicates the problem, much like pus infects and irritates a wound and delays healing.
The muscles that surround the airways may tighten when they should not, causing bronchospasm. These narrowed airways prevent all the "used" air from leaving the lungs. Bronchospasm, inflammation, and swelling all make the space inside the airways smaller. This reduces the amount of air that can flow in and out of the lungs.
The first symptom of chronic bronchitis is a persistent cough that brings up mucus. This is often followed by wheezing, shortness of breath, and frequent chest infections. The symptoms of bronchitis can usually be relieved or improved with treatment.
Emphysema develops when many of the small air sacs or alveoli in the lungs are destroyed. This reduces their elasticity and decreases their ability to pass oxygen into the blood and remove carbon dioxide from the blood.
Shortness of breath is the major symptom of emphysema. At first, this difficulty in breathing may occur only with heavy exercise. Later it happens with light exercise and, still later, even when walking or engaging in other everyday activities. Many people who have emphysema also have chronic bronchitis. The mucus produced by these inflamed airways makes breathing even more difficult.
In most cases, a person's lungs can take a lot of abuse. It may be 20 or more years before someone who has emphysema notices a change in his or her health. However, when emphysema is diagnosed early, more can be done to treat it. By stopping smoking and using appropriate treatments or medication, persons with emphysema can generally lead a comfortable life.
What causes COPD?
Asthmatic bronchitis, chronic bronchitis, and emphysema develop as a result of one or more of these factors:
- cigarette smoking,
- family susceptibility, or
- inhaling large amounts of dust at work or at home.
Conditions that can make these diseases worse are frequent colds or infections in the nose, sinus, throat, or chest.
It is also known that emphysema can be hereditary. In some families this might be due to a lack of normal lung "defenses" that fight damage within the lung. It may also be because certain habits are passed along to other family members. For example, if parents smoke, there is a good chance that their children will smoke. Since smoking is the main cause of COPD, persons with family members who smoke are at greater risk of getting these diseases.