Chronic Obstructive Pulmonary Disease (COPD)

Introduction

From an early age we are educated that smoking can have negative consequences on our health. However, many people ignore the advice and become smokers. Chronic Obstructive Pulmonary Disease or COPD is a perfect example of what smoking can do to your lungs. While smokers are not the only people who develop COPD, they are certainly at the greatest risk. COPD is characterized by a chronic cough and shortness of breath that continues to worsen over time. It continues to be one of the top five causes of death and decreased quality of life in the United States. While COPD is not completely reversible, treatment can be very effective in minimizing the negative impact of COPD on a person's life.

What is it?

COPD is a condition in which a reduction of airflow to the lungs occurs, either because of blockage or excess mucus secretion. COPD will usually worsen with time, especially if untreated. It may be only partially reversible. This is usually due to chronic bronchitis or emphysema, which are the two main types of COPD.

  1. Chronic Bronchitis: Chronic bronchitis is the term that describes the blockage of the airways of the lungs as a result of foreign substances, inflammation, or mucus build-up. People with chronic bronchitis have increased mucus secretion and a chronic cough that persists for at least 3 months over two consecutive years. These symptoms will typically occur almost every day. If you have chronic bronchitis and smoke, you are at an increased risk for worsening of the disease.

  2. Emphysema: Emphysema is a condition that involves destruction of the lungs. This happens because the air spaces in the lungs become enlarged. The air passageways and blood vessels of the lungs (the bronchioles, alveoli, and capillaries) that allow oxygen and carbon dioxide to be exchanged become inflamed and damaged.

While distinguishing between chronic bronchitis and emphysema may be important in determining treatment, many medical professionals tend not to classify patients into one category or another. This is because many patients oftentimes exhibit features of both chronic bronchitis and emphysema.

What causes it?

Most cases of COPD are caused by repeatedly breathing in fumes or irritants that can cause damage to the lungs or airways. The lungs and airways are very sensitive and can be damaged easily.

COPD is most commonly caused by cigarette smoking, but cigars and pipe tobacco may also contribute to the development of COPD, especially when inhaled. The mechanism by which smoking worsens or causes COPD is multi-factorial. It is not the nicotine from cigarettes, cigars, and pipes that causes damage to the lungs, but instead, it's the additives and the smoke itself. There are 599 U.S. government approved additives for cigarettes. A short list includes ammonia, arsenic, hydrogen cyanide, and formaldehyde. These additives and smoke can decrease lung function, directly damaging the lungs, decreasing important enzymes, and constricting lung vessels (such as bronchioles, alveoli, and capillaries).

Besides cigarette smoke, other irritants such as chemicals or chemical fumes can lead to the development of COPD. Persons who work in environments that are overly dusty may also be prone to developing COPD. These irritants can cause the lungs to become inflamed and airways to narrow. Additionally, elastic fibers in the lungs that allow them to expand and retract can become damaged, which makes breathing more difficult.

In addition to smoking and other inhaled irratants, a deficiency in a genetic marker called alpha-1 anti-trypsin (AAT) has also been linked to COPD. AAT is a small protein that protects lung cells. A deficiency in AAT (caused by a genetic mutation) can result in lung cell damage and eventually COPD. A true AAT deficiency accounts for less than 1% of COPD cases.

Finally, chronic infections such as active tuberculosis (TB), recurrent pneumonia, or recurrent fungal infections in the lungs, can lead to COPD. Lung infections that occur repeatedly wear out the lung over time and may cause irreparable damage.

Who has it?

The exact prevalence of COPD is not well defined, yet it affects tens of millions of Americans and is a serious health problem in the U.S. According to national survey data, it is estimated that more than 12.1 million individuals suffer from COPD, and the true prevalence of individuals with chronic airflow obstruction symptoms may be as high as 24 million.

The majority of people suffering from COPD have chronic bronchitis, although emphysema is often a more problematic disease. Emphysema often results in a greater decrease in quality of life and an increase in death compared to chronic bronchitis.

COPD is the fourth leading cause of death due to disease exceeded only by cancer, heart disease, and stroke. COPD is the only cause of death that has increased in frequency over the past 30 years and is projected to become the third leading cause of death by the year 2020.

Although the disease is more prevalent in males, the number of females affected is increasing at an alarming rate because the number of women smokers is increasing at a greater rate than the number of male smokers. In fact, recent studies from developed countries show that the prevalence of the condition is now almost equal in men and women. COPD affects Caucasians more often than it affects other race groups because of increased smoking in this group. Approximately 80 to 90 percent of COPD cases are caused by smoking; a smoker is 10 times more likely than a nonsmoker to die of COPD. People older than 65 years of age are the most susceptible to the disease. Emphysema is more often seen in people of advanced age, whereas chronic bronchitis is seen in all age groups. If you smoke, you have an increased chance for COPD.

What are the risk factors?

Most risk factors for COPD are factors that can be controlled by lifestyle modifications. The only non-modifiable risk factors are the deficiency of the genetic factor alpha-1 anti-trypsin (AAT) in the blood, your age and gender. Risk factors include:

  • Smoking (cigarettes, cigars, and pipes) -- This is the number one cause of COPD. By stopping smoking, you have a chance of preventing the disease.

  • Occupational exposure to inhaled chemicals -- Inhaling chemicals such as gas, sulfur dioxide, nitrogen dioxide, or dry particulate chemicals (for example, microscopic particles) for extended periods of time can cause irritation to the lungs and eventually lead to COPD. Inhalation of such chemicals occurs most frequently in industrial workplaces (for example, processing plants, chemical plants, textile plants, etc.).

  • Increasing Age -- COPD occurs predominantly in individuals older than 40 years

  • Gender -- The number of deaths due to COPD in women have exceeded that of men for the past four years. In 2003, 63,000 women died from COPD, compared to 59,000 men. This is likely because the number of women smokers is increasing at a greater rate than the number of male smokers. Some studies have suggested that women are more susceptible to the effects of tobacco smoke than men.

  • Asthma -- Asthma is a chronic lung disease characterized by limited airflow to the lungs causing inflammation, irritation, and swelling of the lung vessels (bronchioles, alveoli, and capillaries). Worsening of asthma can damage the lung tissues and lead to COPD.

  • Lung Infections -- Chronic lung infections or lung infections that linger for extended periods of time may increase an individual's risk for developing COPD. Lung infections put stress on the lung and can lead to physical damage. Such lung infections may include chronic pneumonia, active tuberculosis (TB), or recurrent fungal infections.

  • Pollution -- The incidence of COPD is greater in cities that are congested and heavily populated (for example, Detroit, Los Angeles, and New York City). This increased incidence is thought to be due to increased air pollution.

  • Dust -- Inhalation of dust, such as silica dust, can cause irritation to the lungs and eventually lead to COPD. Silica dust is often found in workplaces that process glass.

  • Lower Economic Status -- Individuals of lower economic status often live in higher polluted areas near factories, highways, and areas with increased air and water pollution. Individuals of lower economic status are also more likely to smoke, which may also contribute to the development of COPD.

  • Work environment -- Individuals who work in chemical plants, mines, and buildings with asbestos have an increased chance of inhaling harmful microscopic particles that may damage their lungs.

  • Alpha-1 anti-trypsin (AAT) -- This is a genetic marker that is decreased in patients with COPD, especially emphysema.

What are the symptoms?

The most common symptoms of COPD include progressive difficulty breathing, cough, and sputum production; however, a complete list of signs and symptoms is provided below. As discussed previously, many individuals will have symptoms of both chronic bronchitis and emphysema.

Chronic Bronchitis:

  • Chronic cough that continues to worsen.
  • Sputum production, which may be discolored.
  • Mild difficulty of breathing -- this may include problems with breathing while sleeping or during exercise.
  • Wheezing -- A high-pitched sound heard when breathing normally.
  • Crackles -- A "popping" sound heard when breathing in. Your doctor can detect crackles in the lungs when listening to your lungs with a stethoscope.
  • Decreased pulmonary function tests -- Tests performed on the lungs at a doctor's office or other healthcare facility.
  • "Blue bloater" -- Retaining carbon dioxide at the extremities (for example, the toes, fingers, or lips) causes a bluish color because of the increased carbon dioxide and decreased oxygen in the blood. Individuals may also appear bloated because their chest becomes enlarged as the lungs retain carbon dioxide.
  • Barrel Chest -- Enlargement of the chest is due to increased carbon dioxide in the lungs.
  • Obesity- While obesity is not a true sign or symptom of chronic bronchitis, many afflicted individuals develop a complication known as cor pulmonale, which leads to water retention that accumulates in a persons extremities (such as the lower legs). Also a person's exercise tolerance may be decreased, and therefore weight gain may ensue because the afflicted individual may become physically inactive.

Emphysema:

  • Cough -- Individuals with emphysema often have a hacking cough.
  • Sputum -- The sputum produced is often thick in consistency. Because of its thickness, individuals may be unable to cough it up.
  • Severe difficulty of breathing -- This can happen any time of the day but may worsen at night or during exercise. Individuals with emphysema often sit with their hands on their knees to help them breath. They may also breathe with "pursed lips," which looks like they are breathing through a straw.
  • Increased heart rate -- Normal heart rate is between 60 and 90 beats per minute. Increased heart rate is defined as heart rate greater than 100 beats per minute. A way to estimate heart rate is to take your pulse. You should be able to find a pulse at your wrist, count the number of beats you feel for thirty seconds, and multiply that by two. This will give your estimated heart rate in beats per minute.
  • Decreased breath sounds resulting from increased air in the lungs. A doctor can detect decreased breath sounds by listening to your lungs with a stethoscope.
  • Decreased pulmonary function tests -- Tests performed on the lungs at a doctor's office or other healthcare facility.
  • "Pink puffers" -- Individuals with emphysema may turn pink while breathing. The breathing is rapid because they can't seem to get enough air to their lungs; this causes them to become flushed.
  • Many individuals with emphysema are thin in appearance due to continual increased energy demands to breath normally.

How is it treated?

Treatment of COPD is based on the severity of the disease. To measure disease severity, pulmonary function tests (PFT's) are often performed to measure how well air can move in and out of the lungs. The most common PFT is spirometry. The results from this test as well as others allow doctors to stage an individual properly and thus provide the most appropriate treatment. The most common value looked at by a doctor is the amount of air a person can exhale in one second which is known as FEV1.

The stages of COPD are:

  • Stage 0 (at risk): A person may have one or more symptoms such as a chronic cough, breathlessness, or sputum production. This category also would include people that have been exposed to the risk factors mentioned previously. However, people in this stage generally have normal lung function.

  • Stage I (Mild): FEV1 lung function is less than or equal to 80 percent of predicted normal lung function. There is minimal impact on health-related quality of life. Patients at this stage may not even be aware they have the disease. Some patients have symptoms while others do not at this stage.

  • Stage II (Moderate): FEV1 lung function is 50 to 80 percent of predicted normal lung function. Typically, patients experience shortness of breath upon exertion, and symptoms have a significant impact on health-related quality of life. It is this stage that patients most often begin to seek medical attention.

  • Stage III (Severe): FEV1 lung function is 30 to 50 percent of predicted normal lung function, and there is a profound impact on health-related quality of life. At this stage, the patient will most likely experience repeated attacks of shortness of breath often requiring medical help.

  • Stage IV (Very Severe): FEV1 less than 30 percent predicted or respiratory failure (unable to breathe without assistance) is present. These patients may need consistent help from healthcare professionals and may die from respiratory failure at this stage.

Once the stage of COPD is identified, appropriate treatment can begin. The main goal of treatment is to prevent or minimize disease progression. Additional treatment goals include symptom relief, improvement in exercise tolerance, improvement of overall health, prevention of exacerbations, prevention of complications, reduction of the negative effects COPD may have on a person's daily living, and lastly, prevention of death. Treatment approaches are described below.

For individuals who are at risk for COPD, the most important treatment is to avoid risk factors that can cause COPD. These individuals should also get a flu vaccine annually and stay current with their pneumonia vaccination.

For individuals with mild COPD, treatment should start with identification and avoidance of risk factors. Drug treatment should begin with a short acting inhaled bronchodilator such as albuterol (a beta-agonist) or ipratropium (an anticholinergic) if symptoms cannot be controlled by eliminating risk factors. Combination inhaled products such as Combivent (which contains an ipratroprium and albuterol) are sometime prescribed. Flu and pneumonia vaccines are also needed since these illnesses can negatively impact COPD by causing sudden periods of COPD disease worsening known as "exacerbations".

Individuals with moderate COPD are typically also treated with one or more long-acting bronchodilators in addition to the treatment used for mild disease. Long acting bronchodilators include salmeterol or formoterol (long-acting beta-agonists) and tiotropium (a long-acting anticholinergic). These long acting bronchodilators provide sustained effects to the lungs and airways that are needed by individuals who experience symptoms on a more continual basis. Another medication sometimes used due to its prolonged effect is theophylline SR; however use of this medicine requires careful monitoring by a doctor.

Individuals with severe COPD, in addition to receiving therapies described in both mild COPD and moderate COPD, typically also receive inhaled glucocorticosteroids such as fluticasone or budesonide. Inhaled steroids can help reduce inflammation in the lungs and airways that can limit a persons breathing. Steroids are also useful in reducing the number of exacerbations a person may have.

Individuals with very severe COPD in addition to receiving the therapies described for mild COPD, moderate COPD, and severe COPD, may also be treated with oxygen or even surgery. The use of oxygen should be reserved for patients with respiratory failure, very severe COPD or for individuals who are still symptomatic despite taking beta-agonists, theophylline, and corticosteroids. The major surgical procedures include:

  • Bullectomy- removing a part of the lung which is damaged.

  • Lung Volume Reduction Surgery- parts of the lung are removed to stop the lung from overly increasing in size. This procedure has limited effectiveness and is not widely used.

  • Lung Transplantation- replacing a damaged lung or lungs with healthy donor lungs.

In addition to the standard treatments for COPD, many people with COPD often complain of chronic thick mucus. This can be treated with a mucolytic (or mucus thinner) such as guaifenesin, which will thin the mucus and may decrease cough. Increasing water intake can also help thin the mucus. While agents such as these may help some individuals, there is a lack of evidence supporting their continual use.

CFC's in Inhalers and Depletion of the Ozone

The production of substances that damage the earth's ozone layer is being phased out world wide under the terms of an international agreement called the Montreal Protocol on Substances that Deplete the Ozone Layer. Since many of the metered-dose inhalers (MDIs) available in the United States for the treatment of COPD contained ozone-damaging chlorofluorocarbons (CFCs), many of these MDIs are being reformulated to no longer use CFCs. Many products will be reformulated with the propellant hydrofluoroalkane (HFA), which carries medicine into the lungs with no known ozone-depleting chemicals. The reformulation effort is underway and several non-CFC products are currently approved and/or marketed for a range of different drugs (including non-CFC MDI versions for albuterol, beclomethasone, fluticasone, and ipratropium, as well as dry powder inhaler (DPI) versions of fluticasone, formoterol, and salmeterol.) Several more non-CFC products are currently being developed.

Do not be concerned that the medicines you need to treat your COPD will be removed from the market. CFC-containing MDIs will not be removed by the FDA until sufficient alternative medicines exist to serve the needs of patients. The reformulation effort should be complete by December 31, 2008, when all production and sale of MDIs that contain CFCs must stop.

Helping Yourself

Changing your lifestyle may improve your COPD. Smoking has been shown to increase the risk of COPD by damaging the lungs. The additives and smoke in cigarettes, cigars, and pipes are irritating to lung tissue. There are many treatment options for smoking cessation. These include group support, medications, and self-help. Group support can include a therapist and other people trying to quit smoking. You can get more information from a healthcare provider in your area. You can also find information on smoking cessation at http://www.surgeongeneral.gov/tobacco/default.htm or http://www.quitnet.org. Both prescription and nonprescription drugs are available to aid in smoking cessation. Nonprescription products include nicotine gum and the nicotine patch. Prescription medications include buproprion SR (Zyban), nicotine inhalers, and nasals sprays. Many smokers have smoking "triggers," such as smoking after waking up or smoking after meals and snacks. Changing your daily routine may help you deal with these triggers and quit smoking.

You should also ask your healthcare provider if there is a place where you can go to exercise your lungs, also known as pulmonary rehabilitation centers. The lung exercises will strengthen your lungs and help prevent further complications. Support groups may be available and your healthcare provider should provide you information. You can also try http://www.copd-support.org.

If you have COPD, it is important to avoid respiratory infections. Get a pneumonia vaccination as advised by your doctor and an annual influenza immunization. Also, avoid direct contact with people who have a cold or the flu.

Finally, make sure that you are using your inhalers correctly to get the maximum benefit from your medication. DrugDigest has an online video showing how to use your inhalers correctly; visit the "Using Medications" section for more information.

What is on the horizon?

Researchers are continually researching new and more effective ways of treating COPD. Currently, researchers are attempting to get a better understanding of the disease to be able to more effectively treat COPD. There are several medications that are being researched. One such area of research is cytokine modulators. These substances are thought to work on certain chemicals in the body that may worsen COPD. Another option for some individuals may be surgery. There have been studies showing that emphysema patients may benefit from surgery to decrease their lung volume. It is not fully understood why, but lung surgery has been shown to increase quality of life. Investigators are also researching ways to diagnose and monitor the progression of the disease. In addition, more smoking cessation education is being promoted.

The use of inhaled and oral corticosteroids in COPD is somewhat controversial. There is continuous research that is giving added support to using oral corticosteroids short term to prevent exacerbations of COPD. A study reported in the New England Journal of Medicine in June of 2003 found that early use of steroids, within hours of the onset of symptoms, helps prevent exacerbations (a sudden worsening of the condition). Side effects, which are common when using oral corticosteroids, from short-term use of oral steroids are generally minimal.

It is now recognized that 10 to 20 percent of COPD patients have never smoked. Furthermore, only a fraction of smokers do eventually become COPD patients suggesting that genetics and environmental factors play a more important role than what was originally thought. Researches are beginning to further look into air pollution and occupational hazards that lead to COPD. In addition, analysis of patients in National Emphysema Treatment Trial and the National Institutes of Health studies are revealing genetic associations that put people at risk for developing COPD.

Inhaled corticosteroids have been studied for their use in COPD. They are currently recommended for use patients with severe COPD who experience repeat exacerbations. Many combination corticosteroid and bronchodilator products have been manufactured. Currently there is a new combination product known as Symbicort that is in the final stages of trials. This new product has shown promising results in treating COPD and most likely will be seeking FDA approval in the future.

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Chronic Obstructive Pulmonary Disease (COPD) Health Condition Last Updated: February 2008

Note: The above information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist, or other healthcare professional. It is not intended to diagnose a health condition, but it can be used as a guide to help you decide if you should seek professional treatment or to help you learn more about your condition once it has been diagnosed.

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