Filed under: Respiratory Health
Chronic obstructive pulmonary disease (COPD) refers to a group of lung diseases that block airflow and make it increasingly difficult for you to breathe.
Emphysema and chronic bronchitis are the two main conditions that make up COPD, but COPD can also refer to damage caused by chronic asthmatic bronchitis. In all cases, damage to your airways eventually interferes with the exchange of oxygen and carbon dioxide in your lungs.
COPD is a leading cause of death and illness worldwide. Most COPD is caused by long-term smoking and can be prevented by not smoking or quitting soon after you start. Damage to your lungs can't be reversed, so treatment focuses on controlling symptoms and minimizing further damage.
In general, symptoms of COPD don't appear until significant lung damage has occurred, and they usually worsen over time. People with COPD are also likely to experience episodes called exacerbations, during which their symptoms suddenly get much worse. Beyond this, signs and symptoms of COPD can vary, depending on which lung disease is most prominent. It's also possible to have many of these symptoms at the same time.
Signs and symptoms of emphysema include:
* Shortness of breath, especially during physical activities
* Chest tightness
Chronic bronchitis occurs mainly in smokers. It's defined as a cough that you have at least three months a year for two consecutive years. People who continue to smoke may go on to develop emphysema, but in smokers who are able to quit, the cough may clear in a few days or weeks.
Signs and symptoms of chronic bronchitis include:
* Having to clear your throat first thing in the morning, especially if you smoke
* A chronic cough that produces yellowish sputum
* Shortness of breath in the later stages
* Frequent respiratory infections
Chronic asthmatic bronchitis
Chronic asthmatic bronchitis is usually chronic bronchitis combined with asthma (bronchospasm). Asthma can occur when inflamed and infected secretions irritate the smooth muscles in your airways. Symptoms are similar to those of chronic bronchitis, but you're also likely to have intermittent — or even daily — episodes of wheezing.
How your lungs work
Air travels down your windpipe (trachea) and into your lungs through two large tubes (bronchi). Inside your lungs, these tubes divide many times — like the branches of a tree — into many smaller tubes (bronchioles) that end in clusters of tiny air sacs (alveoli). The air sacs have very thin walls full of tiny blood vessels (capillaries). The oxygen in the air you inhale passes into these blood vessels and enters your bloodstream. At the same time, carbon dioxide — a waste product of metabolism — is removed and exhaled.
To force air out of your body, your lungs rely on the natural elasticity of the bronchial tubes and air sacs. When these are damaged, they lose their elasticity and partially collapse when you exhale, trapping air beyond the collapsed areas.
Causes of airway obstruction
COPD primarily refers to obstruction in the lungs from two chronic lung conditions. Many people with COPD have both.
* Emphysema. This lung disease causes inflammation within the fragile walls of the alveoli. This can destroy some of the walls and elastic fibers, which allows small airways to collapse when you exhale, impairing airflow out of your lungs.
* Chronic bronchitis. This condition, which is characterized by an ongoing cough, causes inflammation and narrowing of the bronchial tubes. Chronic bronchitis also causes increased mucus production, which can further block the narrowed tubes.
Asthmatic bronchitis — also known as bronchial asthma — refers to chronic bronchitis accompanied by contractions of the muscle fibers in the lining of the airways (bronchospasm). Chronic asthmatic bronchitis is sometimes classified as COPD.
Cigarette smoke and other irritants
In the vast majority of cases, the lung damage that leads to COPD is caused by long-term cigarette smoking. But other irritants can cause COPD, including cigar smoke, secondhand smoke, pipe smoke, air pollution and certain occupational fumes. Gastroesophageal reflux disease (GERD), which occurs when stomach acids wash back up into your esophagus, can aggravate COPD and may even cause it in some people.
In rare cases, COPD results from a genetic disorder that causes low levels of a protein called alpha-1-antitrypsin.
Risk factors for COPD include:
* Exposure to tobacco smoke. The most significant risk factor for COPD is long-term cigarette smoking. The more years you smoke and the more packs you smoke, the greater your risk. Symptoms of COPD usually appear about 10 years after you start smoking. Pipe smokers, cigar smokers and people exposed to large amounts of secondhand smoke also are at risk.
* Occupational exposure to dusts and chemicals. Long-term exposure to chemical fumes, vapors and dusts can irritate and inflame your lungs.
* Gastroesophageal reflux disease (GERD). This condition is a severe form of acid reflux — the backflow of acid and other stomach contents into your esophagus. GERD can make COPD worse and may even cause it in some people.
* Age. COPD develops slowly over years, so most people are at least 40 years old when symptoms begin.
* Genetics. A rare genetic disorder known as alpha-1-antitrypsin deficiency is the source of a few cases of COPD. Researchers suspect that other genetic factors may also make certain smokers more susceptible to the disease.
Complications of COPD include:
* Respiratory infections. When you have COPD, you're more likely to get frequent colds, the flu or pneumonia. Plus, any respiratory infection can make it much more difficult to breathe and produce further irreversible damage to the lung tissue. Talk to your doctor about annual flu shots and regular pneumococcal vaccines.
* High blood pressure. COPD may cause high blood pressure in the arteries that bring blood to your lungs (pulmonary hypertension).
* Heart problems. For reasons that aren't fully understood, COPD increases your risk of heart disease, including heart attack.
* Lung cancer. Smokers with chronic bronchitis are at a higher risk of developing lung cancer than are smokers who don't have chronic bronchitis.
* Depression. Difficulty breathing can keep you from doing activities that you enjoy. And it can be very difficult to deal with a disease that is progressive and incurable. Talk to your doctor if you feel sad or helpless or think that you may be experiencing depression.
Preparing for your appointment
If your primary care doctor suspects that you have COPD, you'll likely be referred to a pulmonologist, a doctor who specializes in lung disorders. These suggestions may help you get the most from your appointment:
* Be aware of any pre-appointment restrictions. At the time you make your appointment, be sure to ask if there's anything you need to do in advance to prepare for diagnostic tests you might have.
* Write down all symptoms and changes you're experiencing, even if they seem unrelated to your lungs or breathing.
* Write down key personal information, including any recent life changes or other stressors.
* Make a list of important medical information, including recent surgical procedures, the names of all medications you're taking and any other conditions for which you've been treated.
* Write down questions to ask your doctor. For instance, you'll want to learn more about treatment options for COPD and the long-term outlook for people who have the disease.
* Have a friend or family member accompany you. Shortness of breath from any cause is a serious problem. A friend or family member can provide emotional support as well as help remember information that you may have forgotten or missed.
Tests and diagnosis
If you have symptoms of COPD and a history of exposure to lung irritants — especially cigarette smoke — your doctor may recommend these tests:
* Pulmonary function tests. Spirometry is the most common lung function test. During this test, you'll be asked to blow into a large tube connected to a spirometer. This machine measures how much air your lungs can hold and how fast you can blow the air out of your lungs. Spirometry can detect COPD even before you have symptoms of the disease. It can also be used to track the progression of disease and to monitor how well treatment is working.
* Chest X-ray. A chest X-ray can show emphysema — one of the main causes of COPD. An X-ray can also rule out other lung problems or heart failure.
* Arterial blood gas analysis. This blood test measures how well your lungs are bringing oxygen into your blood and removing carbon dioxide.
* Sputum examination. Analysis of the cells in your sputum can help identify the cause of your lung problems and help rule out some lung cancers.
* Computerized tomography (CT) scan. A CT scan is an X-ray technique that produces more-detailed images of your internal organs than those produced by conventional X-rays. A CT scan of your lungs can help detect emphysema and help determine if you might benefit from surgery for COPD.
Treatments and drugs
There's no cure for COPD, and you can't undo the damage to your lungs. But COPD treatments can control symptoms, reduce your risk of complications and exacerbations, and improve your ability to lead an active life.
The most essential step in any treatment plan for smokers with COPD is to stop all smoking. It's the only way to keep COPD from getting worse — which can eventually result in losing your ability to breathe. But quitting smoking is never easy. And this task may seem particularly daunting if you've tried to quit before. Talk to your doctor about nicotine replacement products and medications that might help, as well as how you might handle relapses. It's not known what role exposure to secondhand smoke plays in COPD, but avoid it whenever possible.
Doctors use several basic groups of medications to treat the symptoms and complications of COPD. You may take some medications on a regular basis and others as needed:
* Bronchodilators. These medications — which usually come in an inhaler — relax the muscles around your airways. This can help relieve coughing and shortness of breath and make breathing easier. Depending on the severity of your disease, you may need a short-acting bronchodilator before activities, a long-acting bronchodilator that you use every day, or both.
* Inhaled steroids. Inhaled corticosteroid medications can reduce airway inflammation and help you breathe better. But prolonged use of these medications can weaken your bones and increase your risk of high blood pressure, cataracts and diabetes. They're usually reserved for people with moderate or severe COPD.
* Antibiotics. Respiratory infections, such as acute bronchitis, pneumonia and influenza, can aggravate COPD symptoms. Antibiotics can help fight bacterial infections, but are only recommended when necessary.
Surgery is an option for some people with some forms of severe emphysema who aren't helped sufficiently by medications alone:
* Lung volume reduction surgery. In this surgery, your surgeon removes small wedges of damaged lung tissue. This creates extra space in your chest cavity so that the remaining lung tissue and the diaphragm work more efficiently. The surgery has a number of risks, and long-term results may be no better than for nonsurgical approaches.
* Lung transplant. Single-lung transplantation may be an option for certain people with severe emphysema who meet specific criteria. Transplantation can improve your ability to breathe and be active, but it doesn't appear to prolong life and you may have to wait for a long time to receive a donated organ. So the decision to undergo lung transplantation is complicated.
Doctors often use these additional therapies for people with moderate or severe COPD:
* Oxygen therapy. If there isn't enough oxygen in your blood, you may need supplemental oxygen. There are several devices to deliver oxygen to your lungs, including lightweight, portable units that you can take with you to run errands and get around town. Some people with COPD use oxygen only during activities or while sleeping. Others use oxygen all the time. Oxygen therapy can improve heart function, exercise capacity, depression, mental clarity and quality of life. In some people, it may also extend life. Talk to your doctor about your needs and options.
* Pulmonary rehabilitation program. Comprehensive pulmonary rehabilitation may be able to decrease the length of any hospitalizations you require, increase your ability to participate in everyday activities and improve your quality of life. These programs typically combine education, exercise training, nutrition advice and counseling. If you are referred to a program, you'll probably work with a range of health care professionals, including physical therapists, respiratory therapists, exercise specialists and dietitians. These specialists can tailor your rehabilitation program to meet your needs.
Even with ongoing treatment, you may experience times when symptoms suddenly get worse. This is called an acute exacerbation, and it may cause lung failure if you don't receive prompt treatment. Exacerbations may be caused by a respiratory infection or a change in temperature or air pollution. Whatever the cause, it's important to seek prompt medical help if you notice more coughing, a change in your mucus or if you have a harder time breathing.
When exacerbations occur, you may need additional medications, supplemental oxygen or treatment in the hospital. Once symptoms improve, you'll want to take measures to prevent future exacerbations. This may include quitting smoking, avoiding indoor and outdoor pollutants as much as possible, exercise and treatment for GERD.
Lifestyle and home remedies
If you have COPD, you can take steps to feel better and slow the damage to your lungs:
* Control your breathing. Talk to your doctor or respiratory therapist about techniques for breathing more efficiently throughout the day. Also be sure to discuss breathing positions and relaxation techniques that you can use when you're short of breath.
* Clear your airways. In COPD, mucus tends to collect in your air passages and can be difficult to clear. Controlled coughing, drinking plenty of water and using a humidifier may help.
* Exercise regularly. It may seem difficult to exercise when you have trouble breathing, but regular exercise can improve your overall strength and endurance and strengthen your respiratory muscles.
* Eat healthy foods. A healthy diet can help you maintain your strength. If you're underweight, your doctor may recommend nutritional supplements. If you're overweight, losing weight can significantly help your breathing, especially during times of exertion.
* Avoid smoke. In addition to quitting smoking, it's important to avoid places where others smoke. Secondhand smoke may contribute to further lung damage.
* Pay attention to frequent heartburn. Constant heartburn can indicate gastroesophageal reflux disease (GERD), a condition in which stomach acid or, occasionally, bile flows back into your food pipe (esophagus). This constant backwash of acid can aggravate COPD, but treatments for GERD can help. Talk to your doctor if you have frequent heartburn.
* See your doctor regularly. Stick to your appointment schedule, even if you're feeling fine. It's important to steadily monitor your lung function.
Coping and support
Living with COPD can be difficult — especially as it becomes more and more difficult to catch your breath. You may have to give up activities you previously enjoyed. And your family and friends may face significant changes and challenges in an effort to help you. You may also find yourself facing some tough questions, such as how long you have to live and what you will do if you no longer can take care of yourself.
It can help to share your fears and feelings with your family, friends and doctor. You may also want to consider joining a support group for people with COPD. And you may benefit from counseling if you feel depressed or overwhelmed.
Unlike some diseases, COPD has a clear cause and a clear path of prevention. The vast majority of cases are directly related to cigarette smoking, and the best way to prevent COPD is to never smoke — or to quit smoking.
If you're a longtime smoker, these simple statements may not seem so simple, especially if you've tried quitting — once, twice or many times before. But it's critical to find a tobacco-cessation program that can help you kick the habit for good. It's your best chance for preventing damage to your lungs.
Occupational exposure to chemical fumes and dust is another risk factor for COPD. If you work with this type of lung irritant, talk to your supervisor about the best ways to protect yourself, such as wearing a mask.