Chronic obstructive pulmonary disease (COPD) is a chronic, progressive condition characterized by coughing, wheezing and shortness of breath that can drastically restrict daily activities.
COPD is closely associated with smoking. According to the American Lung Association (ALA), smokers are 12 to 13 times more likely to die from COPD than non-smokers. The ALA also estimates that 80 to 90 percent of COPD deaths are caused by smoking. Second-hand smoke exposure has also been linked to the disease.
Besides smoking, COPD is also associated with exposure to environmental pollutants and organic substances, such as fertilizer. Rarely, COPD may be caused by a genetic deficiency in the protein alpha-1 antitrypsin. Studies have also shown that low levels of alpha-1 antitrypsin coupled with known risk factors such as smoking are particularly dangerous.
Although asthma is a respiratory ailment that may resemble COPD, it is not related to COPD. Both asthma and COPD make breathing more difficult. However, asthma is usually associated with inflammation and is not capable of causing the severe and permanent damage associated with COPD. Asthma and COPD do coexist in some individuals, though the two conditions are usually treated separately. People with asthma and COPD are often more sensitive to airborne irritants and allergens.
Patients with COPD usually have one of two pulmonary diseases: bronchitis or emphysema. Although these conditions are generally linked with COPD, they should not be confused with the disease. These two conditions often coexist in individuals with COPD.
Chronic bronchitis is a condition in which the breathing passages to and from the lungs (bronchioles) have become irritated, decreasing air flow and resulting in greater mucus production. This situation leaves the lungs at greater risk of infection.
Emphysema is a condition in which the air sacs in the lungs (alveoli) are damaged, interfering with the normal exchange of oxygen and carbon dioxide. Some of them eventually collapse. Thus, a single, large useless hole (a bulla) takes the place of the many functional sacs (alveoli) that had been supporting the airways (bronchioles). This makes it harder to exhale stale air from the lungs and inhale a full breath of clean air.
Because COPD involves lung damage that gradually occurs over many years, the condition is most common in patients over the age of 60. It also occurs more often in women. In addition, women are more likely to visit a hospital emergency room for COPD, require hospitalization for COPD and die from COPD. Children do not develop the condition.
According to the ALA, COPD is consistently among the five leading causes of death in the United States. The U.S. Centers for Disease Control and Prevention (CDC) estimate that approximately 10 million adults were diagnosed with COPD in the United States in the year 2000, and as many as 24 million may be affected. It is also responsible for more than 1 million emergency room visits every year.
Currently, there is no cure for COPD. Because the disease is a chronic, progressive condition, physicians usually strive to manage the disease in close partnership with the patient. It is essential that smoking is discontinued and medications and therapy be closely adhered to. As the disease worsens, patients are at risk of experiencing acute episodes of COPD, accompanied by breathlessness, lack of oxygen, severe coughing and other symptoms. An acute episode will usually require hospitalization.
What causes chronic obstructive pulmonary disease?
In the overwhelming majority of chronic obstructive pulmonary disease (COPD) cases, the main cause of lung damage is smoking tobacco. A classic COPD patient is a person around the age of 50 or 60 who has smoked one or more packs of cigarettes per day for over two decades (20 pack years). Although most studies have pointed out the harmful effects of cigarette smoke, recent research has noted that cigar and pipe smoke also appear related to COPD. In addition, recent studies have suggested that breathing in someone else’s smoke (called side-stream or second-hand smoke) can eventually damage the lungs of non-smokers and increase their risk of developing COPD.
Patients who have both COPD and asthma usually cause the serious lung damage associated with severe COPD by continuing to smoke. Asthma is very rarely capable of damaging the lungs as severely as the combination of smoking and COPD. Although coexistent asthma and COPD can result in a more severe overall respiratory condition, the two conditions are usually treated independently.
COPD is typically the result of one of two different lung conditions – emphysema and chronic bronchitis – and the causes of these two conditions can also lead to COPD:
Chronic bronchitis is often the result of smoke that has irritated and damaged the mucous glands, airways and hair-like cells (cilia) that normally wave toxins out of the lungs.
Emphysema is often the result of smoke that has triggered the immune system to produce more harmful enzymes. Although these harmful enzymes are normally prevented from causing any significant damage by a protective protein, smoking reduces the protein’s protective effect. Even if someone has plenty of the protein in their system, smoking generates certain substances that keep the protective protein from doing its job.
Although the main cause of COPD is tobacco smoke, there are also genetic causes. For example, some people’s lungs are more sensitive to irritants, making it more likely that they will develop COPD. Other people are born with an abnormally low level of protective protein (alpha-1-antitrypsin), so there is less protection from harmful enzymes and a greater chance of developing emphysema.
In addition to smoking and genetic factors, the following people are particularly vulnerable to COPD:
People who frequently inhale many airborne irritants (e.g. air pollution and occupational exposure to industrial pollution)
People exposed to excessive fungi/mold
People with few antioxidants (e.g., vitamin C) in their diet
Obesity has been identified as a risk factor for chronic bronchitis, and low body weight has been linked to emphysema. Furthermore, some experts believe that COPD can be a consequence of childhood respiratory infections and recurrent upper respiratory infections (e.g., getting pneumonia year after year). However, researchers are still working to understand the role that infections may play in the development of COPD.
Signs and symptoms of COPD
Chronic obstructive pulmonary disease (COPD) is usually accompanied by the presence of three main symptoms:
Shortness of breath
Because COPD normally results from one of two different lung conditions, emphysema and chronic bronchitis, the symptoms associated with these diseases can also occur in patients.
The symptoms of chronic bronchitis typically include shortness of breath, a nagging cough (often with mucus) and respiratory infection. A diagnosis is often made only after the person has experienced a nagging cough, with quite a bit of mucus, for at least one-quarter of a year, for two years in a row. Because lying flat tends to aggravate symptoms, people in late stages of chronic bronchitis are forced to sleep while sitting up. During these late stages, people may show signs such as a bluish tint to the skin (cyanosis) and/or fluid buildup (edema).
As emphysema develops, shortness of breath is often the first symptom that people notice. Over time, other symptoms appear: a nagging cough (often with mucus), and a gradually worsening ability to exhale. As the disease progresses, it gets harder for people to breathe while physically active. In late stages of the disease, people wheeze and feel like they cannot get enough air even while at rest. At this point, that patient’s overly inflated lungs may produce signs such as flushed skin and an over-inflated chest.
In those cases where COPD and asthma coexist, more intermittent chest symptoms may tend to occur. Nighttime chest symptoms and symptoms that occur as a result of exposure to allergens take place more frequently in these cases.
How is COPD diagnosed?
In many cases, patients experiencing symptoms of chronic obstructive pulmonary disease (COPD), such as coughing or wheezing, have already been diagnosed with either chronic bronchitis or emphysema. In some instances, patients will be diagnosed with one of these two conditions and COPD at the same time. People experiencing symptoms of COPD should immediately notify their physician.
Diagnosis of COPD typically begins with a complete medical history and physical examination. In addition to asking about the symptoms of COPD, the physician will listen to the patient’s chest. If the patient has already been diagnosed with emphysema, the physician will listen for a hollow noise from the chest. If the patient has already been diagnosed with bronchitis, the physician will listen for a wheezing noise from the chest. Additional symptoms may include hyperinflation of the chest.
As part of diagnosing COPD, the physician may also perform any of the following tests:
Arterial blood gas analysis. In this test, blood is drawn from the patient’s artery to measure the levels of oxygen and carbon dioxide. Low oxygen (hypoxia) and high carbon dioxide (hypercapnia) may indicate chronic bronchitis.
Chest x-ray. Although early signs of COPD will not be seen on a chest x-ray, chronic bronchitis might be indicated by the presence of scarring and enlarged walls of the airways. This is called a “dirty chest.” Also, the chest x-rays of advanced emphysema patients often reveal a constricted diaphragm, overly inflated lungs, large spaces (bullae) in the lungs and an abnormally small heart. A type of chest x-ray called a computed axial tomography (CAT) scan may also be done.
Exercise stress test. This test identifies the level at which a patient is able to exercise safely. Oxygen may be administered during the test if needed.
Spirometry. The patient forcefully exhales into a special device (a spirometer) that tells the physician how fully the lungs can inflate, and how severely the airways are obstructed. The patient’s ability to breathe is called the forced expiratory volume (FEV1). Although FEV1 normally begins to deteriorate slowly around the age of 20, people who smoke will have an FEV1 that deteriorates 2 to 3 times faster than normal. Thus, someone with COPD might begin to experience shortness of breath about 20 years sooner than someone without the disease. This test is often used to monitor COPD and the effectiveness of therapy.
Pulse oximetry (“pulse ox”). This quick, painless test measures the amount of oxygen in the blood by attaching a small probe to the ear or finger.
Sputum analysis. A sample of the patient’s mucus is taken for analysis to see if there is a respiratory infection.
How is Chronic obstructive pulmonary disease treated?
Chronic obstructive pulmonary disease (COPD) is treatable through several different methods. The treatment goal is to slow the loss of lung function in patients. Treatment also focuses on reducing symptoms. People who are informed and who follow their physician’s recommendations have an excellent chance of living a fairly normal lifestyle.
Treatment for individuals who have both asthma and COPD is likely to be largely independent for each condition, because asthma usually involves inflammation and COPD usually involves lung destruction. However, some medications, (e.g., corticosteroids) may be beneficial in treating both conditions. Avoidance of smoke and other irritants will also help patients with both types of conditions.
Treatments for COPD include:
Protecting oneself from airborne irritants and quitting smoking
Protecting oneself from contracting another lung disease
Eating a healthy diet
Lifestyle changes are important in the treatment of COPD. Patients need to protect themselves from all airborne irritants. Exhaust fumes, coal dust, air pollution, chimney smoke, hair spray and even perfumes may trigger a coughing fit. Physicians regularly tell their COPD patients that it is essential for them to quit smoking if they have not already done so. They may also ask family members who smoke near the patient to quit smoking as well.
Additionally, it is important for COPD patients to protect themselves as much as possible from contracting another lung disease, such as pneumonia. For this reason, it is very important for COPD patients to wash their hands frequently, keep their homes well-ventilated and free of mold, and get both an annual flu shot and regular pneumonia vaccines. Some COPD patients may consider moving to a warmer climate. If a lung disease is contracted despite the best preventive efforts, it is essential for the patient to seek medical attention as soon as possible.
Another strategy for treating COPD is exercise. However, patients should not overexert themselves. Exercise is helpful in strengthening the respiratory muscles and building tolerance to physical activity. COPD patients are often asked to take several short walks over the course of a day. Other low-impact activities, such as water aerobics and riding a stationary bike, may also be beneficial. COPD patients should consult with a physician before starting a new exercise routine.
COPD patients may also do breathing exercises, in which they practice inhaling as deeply, and exhaling as forcefully, as possible. These exercises help strengthen the muscles used for breathing and make it easier to move air in and out of the lungs, which ultimately helps decrease shortness of breath.
For patients coughing up heavy mucus, it is important to drink plenty of fluids and maintain a high humidity level in the home. Patients can also gently strike their own chest, or have a family member gently strike the back while they are sitting bent over, because this may help to loosen the mucus. Hand-held devices that cause a vibration through the airway can also be used to help loosen mucus. Uncontrolled fits of coughing and tight, restrictive clothing around the chest should be avoided as much as possible.
A healthy diet may help the patient reach and maintain a normal body weight. It should be limited in salt, and high in protein, calcium and potassium. Foods rich in vitamin C may also be helpful because they may thin the patient’s mucus. Avoiding foods that increase the production of mucus, such as dairy products, is another strategy.
Stress management plays an important role in the treatment of COPD. It is extremely stressful for a patient when his or her throat closes, forcing the patient to gasp for air and worry about another trip to the emergency room. A program of stress management can help the patient learn to deal with feelings of fear, depression, anger and the hopelessness that people often feel when first diagnosed with a chronic illness. There may also be local COPD support groups that the patient can join.
Sometimes a number of different medications are prescribed for a COPD patient, and the use of a pillbox can help to make sure that all are taken as prescribed.
Medications that may be prescribed for COPD include:
Anticholinergic agents. These help the muscles around the lungs (bronchial muscles) to relax. This is often the first line of treatment.
Bronchodilators. These widen the airways of the lungs so that more oxygen can be obtained.
Corticosteroids. These appear to have strong anti-inflammatory effects in the lungs, at least in the short term. However, studies have suggested limiting long-term use of steroids and because of their side effects, they are recommended only in patients who are not benefiting from other therapy. Research on the use of inhaled corticosteroids with fewer side effects is ongoing.
Expectorants (mucolytics). These thin the mucus and make it easier to cough up. Although expectorants may increase the patient’s comfort, they have not been shown to increase airflow.
Leukotriene modifiers. These are anti-inflammatory drugs currently prescribed only for asthma, but which may eventually play a role in the treatment of COPD.
Other medications may be prescribed which do not address the COPD itself, but which help to relieve some of the symptoms that COPD patients experience.
These medications include:
Analgesics. These slow the overworked breathing functions of COPD patients. Commonly known as painkillers, these medications may be prescribed for patients having severe difficulty catching their breath.
Diuretics. These treat swelling (edema) by flushing fluids and minerals, especially sodium, from the body. They are also used to treat high blood pressure (hypertension).
Inotropes. These strengthen the heart’s pumping ability.
Vasodilators. These expand blood vessels, allowing blood to flow more freely and the heart to pump more efficiently. These medications may be prescribed for COPD patients who are experiencing fluid buildup or heart disease.
The other major nonsurgical treatment for COPD is oxygen-replacement therapy, which has largely replaced a more uncomfortable COPD treatment: drawing blood (phlebotomy) to rid the body of its oversupply of red blood cells. Oxygen-replacement therapy allows patients to receive additional oxygen from either oxygen cylinders/tanks or electric concentrators, which take the oxygen directly from the air.
Patients breathe the oxygen through either a face mask or a thin plastic tube with two small prongs that go directly into the nostrils (nasal cannula). For patients who have a surgically created hole in their windpipe (following a tracheostomy), another option is a thin plastic tube that goes directly into that hole (transtracheal cannula).
Regardless of how the oxygen is delivered, continuous oxygen-replacement therapy is the only intervention shown to help advanced COPD patients live longer, and oxygen is frequently used during acute episodes. Other patients may benefit from using oxygen therapy only as needed, particularly during physical activity or sleep. Although portable oxygen tanks allow COPD patients far greater mobility, it should be noted that the oxygen is a fire hazard and is barred from some establishments.
To date, surgical treatments for emphysema are only experimental and rarely covered by insurance.
Prevention methods for COPD
The best prevention for chronic obstructive pulmonary disease (COPD) is to abstain from smoking cigarettes, cigars and pipes, because tobacco smoke has been strongly linked to this disease. Patients are encouraged to ask their physician about the many strategies that are available to help them quit smoking. Avoiding other irritants in the air is also important.
Patients who have both asthma and COPD should also try to avoid smoke and other potential irritants and allergens as much as possible. The lung damage caused by COPD can make it easier for a person with asthma to experience an asthma attack.
Research suggests that caring for all lung-related infections is necessary for patients with COPD, particularly if they are recurrent. For example, if a patient is told to take an antibiotic for ten full days, the patient should complete the full course of treatment, even if symptoms subside after only five days. Exercise to maintain full lung capacity, and a healthy diet to maintain normal weight, are also recommended. Finally, some studies suggest that vitamin C can aid in the prevention of COPD.
There is also a screening test that can detect the gene responsible for A1AD emphysema. Couples with a history of this disease on either or both sides of the family may wish to take this test before having children, or to have their children screened. If detected early, regular injections of the protective protein (replacement therapy) can be pursued.
Questions for your doctor
Preparing questions in advance can help patients to have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions regarding chronic obstructive pulmonary disease (COPD):
Do my symptoms indicate COPD?
What tests will you use to determine if I have COPD?
What may have caused me to develop COPD?
Will COPD have an effect on my asthma?
What are my treatment options?
Can you recommend a strategy for me to stop smoking?
Should I make changes in my diet?
Can you recommend stress management techniques?
How can I prevent COPD?
Are my children more likely to develop COPD because I have the condition?
If smoking is stopped during the early stages of COPD, some of the damage in the small airways may return to normal. Individuals with mild COPD that is treated early may be free of disability, except for acute worsening during other illnesses. Individuals with severe COPD will continue to have progressively deteriorating lung function despite treatment and usually become permanently disabled.