Your lung disease is commonly referred to as Chronic Obstructive Pulmonary Disease (COPD). Individuals with COPD can also have symptoms of asthma or other lung conditions as well. Since many of the symptoms of these conditions are quite similar, you may be confused about the way in which they differ from one another.
COPD is a disorder in which there is difficulty moving air in and out of the lungs because of damage to the airways and/or the air sacs or alveoli. Damage to the airways causes bronchitis. Damage to the air sacs causes emphysema. In COPD, the airflow blockage gets worse. However, medicines and other treatments may be able to slow or reverse some of these changes.
Symptoms of COPD are:
- Shortness of breath especially with exertion
- Sporadic worsening of breathing, often with infection or “exacerbations”
Most often, COPD develops as the result of exposure to environmental toxins. The most important toxin is cigarette smoke. The sensitivity of individuals to the effects of cigarette smoke is very variable. Some may smoke very little and develop severe COPD. And others can smoke for many years and not have breathing problems. The sensitivity to cigarette’s effects seems to run in families. For example, identical twins seem to have a similar sensitivity to cigarette smoke. There is a growing awareness that genetics play a role in whether someone gets COPD or not.
A specific genetic disorder has been identified that greatly increases someone’s likelihood of developing COPD. It is called Alpha-1 Antitrypsin Deficiency (or “Alpha-1). People with Alpha-1 have a decreased level of the blood protein called alpha-1 antitrypsin. Individuals with Alpha-1 can develop emphysema (see below), often at a relatively young age. And smoking cigarettes speeds up the development of COPD even more. Alpha-1 can be diagnosed with a simple blood test. But unfortunately, most individuals with COPD from Alpha-1 have never been tested for it. They don’t know they have it. Often, those who have been diagnosed with Alpha-1 were diagnosed with COPD several years before the diagnosis of Alpha-1 itself was made. It is therefore strongly recommended that all individuals with COPD be tested for Alpha-1. This is especially important since there is specific treatment for Alpha-1 that can slow or halt the rapid progress of COPD in these individuals. This treatment is called “augmentation therapy.” It adds to the amount of alpha-1 antitrypsin protein in the blood of individuals with Alpha-1. (For more information about Alpha-1 Antitrypsin Deficiency, visit the Alpha-1 Foundation’s website at www.alphaone.org or AlphaNet at www.alphanet.org).
Most believe that Alpha-1 is only one of many genetic factors linked to COPD. The largest genetic study on COPD, “COPDGene®,” is presently underway. The hope is to learn more about the genetic factors that contribute to the development of COPD. If you are interested in learning more about this study you can go to the website at www.COPDGene.org.
While COPD may be due to smoking, occupational exposures or genetics, most people diagnosed with COPD have similar symptoms of the disease. Regardless of how the disease is acquired, the medical care is similar (except if you have Alpha-1).
Some COPD patients have more features of emphysema. Some have more features of chronic bronchitis. But most folks with COPD have some mixture of the two.
Chronic bronchitis means constant inflammation of the bronchus. Bronchitis is said to be “chronic” when an individual has a productive cough. The cough must have lasted for at least three months during each of two years in a row. And other causes for a cough must have been ruled out. (Other causes of chronic cough include asthma, post-nasal drip and gastro-esophageal reflux disease).
Symptoms of chronic bronchitis are:
- Mucus production
- Shortness of breath
With bronchitis, the bronchial tubes become inflamed and swollen. The mucus glands multiply and mucus production is increased. This all leads to coughing and shortness of breath. In chronic bronchitis, the lining of the bronchial tubes lose the hair-like projections (cilia) that normally help move the mucus up the bronchial tubes so it can be coughed up. When this happens, it becomes harder to cough up mucus. This, in turn, causes more coughing, more irritation and more mucus production. This cycle results in the airways becoming swollen and clogged. This causes obstruction and increased shortness of breath. Individuals with chronic bronchitis almost always have flare-ups of their disease that lead to episodes of greatly increased shortness of breath.
Emphysema is a disorder in which the air sacs, or alveoli, are destroyed. This causes a loss of the lungs’ elasticity. The loss of the walls of the air sacs causes these small structures to combine into larger units. These larger air sacs perform their functions more poorly than the smaller ones. These large air sacs have a lower ability to exchange oxygen and carbon dioxide between inhaled air and the blood. As a result, less oxygen can be absorbed into the blood. In the most severe cases, the amount of carbon dioxide getting exhaled is decreased.
Following the ruin of the small alveoli, the lungs become stretched out. They are no longer able to recoil as they once did to expel air. The supporting tissue of the bronchial tubes can be lost. This causes “flabby” airways that collapse when air is breathed out. Air can become trapped in the lungs. This can lead to a flattening of the diaphragm muscles. This makes them less able to assist in breathing. (The diaphragm is the broad muscle at the bottom of the lungs that acts like a bellows during breathing.)
The major problems caused by emphysema are poor exchange of oxygen with the blood and difficulty breathing air out of the lungs. In mild or moderate emphysema, you may have shortness of breath during intense activity. This can progress slowly and not be noticed. In more severe emphysema, you may have shortness of breath during mild activity and even at rest.
Asthma is defined as reversible airflow blockage with increased reactivity or “twitchiness” of the muscles around the bronchial tubes. The key word here is reversible. In other lung diseases the blockage is not entirely reversible. A key distinction of asthma is that the blockage is reversible.
Asthma has three elements. These are narrowing of the muscles around the bronchial tubes, inflammation of the bronchial tubes and overproduction of mucus. These lead to the blockage of airflow in and out of the lungs. Reversible obstruction means that medicine can cause this condition to improve or become normal.
In COPD, airflow obstruction also may include a significant reversible part. But, in general, this obstruction can never be entirely reversed, even with the use of medicine. Individuals whose airflow obstruction is completely reversible don’t have COPD.
Symptoms of asthma include:
- Chest tightness
Bronchiectasis is a condition that is fairly common in COPD patients. It is defined as enlarged and severely damaged bronchial tubes. With the increased use of CT scanning, there is a growing knowledge that individuals may have major bronchiectasis without obvious symptoms. One way to understand bronchiectasis is to think of a stream in the mountains. When you look at the water in the center of the stream where the current is fast, the water is crystal clear. You can see the pebbles below the surface. On the side of the stream where there is little current, you can see pools with water lilies, green slime and floating debris. These pools are similar to the areas of bronchiectasis. As you can imagine, they are predisposed to infections.
Bronchiectasis can be caused by frequent airway infections. It can also be caused by a single severe episode of infection, such as bronchial pneumonia, tuberculosis or whooping cough. Symptoms of bronchiectasis are caused by the pooling of secretions in these damaged airways. This provides a good breeding ground for many types of bacteria. When symptoms occur, they can include:
- Coughing up lots of mucus that may be foul smelling, discolored and/or bloody
- Shortness of breath
- Frequent infections
In COPD patients, especially those with bronchiectasis, there are often low grade infections by an organism called “mycobacterial avium intracellulare” or MAI. While MAI is in the family of tuberculosis, it is not tuberculosis. It does not spread from person to person. There are now antibiotics that can control this infection. However, the antibiotics may need to be used for many months. They may have side effects. Often folks with MAI, without major symptoms, are followed without treatment.