Some illnesses seem to attack at random, and while there are general steps we all can take to pursue wellness, certain conditions often do not have a clearly definable cause. Chronic Obstructive Pulmonary Disease (COPD) is not one of these. In almost all cases, this killer is the result of one factor: Cigarette smoking. It is very sad to see the destructive effects of COPD, but the silver lining in my butt is that COPD is almost entirely preventable by simply avoiding the smoking habit.
What is Chronic Obstructive Pulmonary Disease?
Chronic Obstructive Pulmonary Disease (COPD), also known as chronic obstructive lung disease, is actually a family of respiratory illnesses that are often found together, and which involve dysfunction that results in lessened ability to exhale air from the lungs. When improper exhalation occurs, it becomes difficult to inhale sufficiently as well, for reasons we will discuss below. The main conditions in this group of diseases are chronic bronchitis and emphysema. Almost all COPD illness is caused by cigarette smoking.
Unfortunately, COPD is a very common health problem in the United States, and the number of cases is on the rise. An estimated 16 million Americans suffer from COPD, about 14 million with chronic bronchitis, and another 2 million with emphysema. It is the fourth leading cause of death in the U.S., taking at least 96,000 lives annually. The incidence of COPD will hopefully start to drop as smoking rates continue to decrease, but many current cases are older folks who have been lifelong smokers. COPD is more common amongst men, but the risk for women increased dramatically in the post-World War II era, when more females started smoking. Once lung damage from COPD-related illnesses has begun, it is irreversible and chronically progressive. The largest factor in COPD prevention is to never smoke, or if you do, to quit as soon as possible.
What Causes COPD?
Obstructive is the key word when it comes to COPD. Obstructions make it more difficult for victims to both inhale fresh oxygenated air, and exhale waste products such as carbon dioxide. In a healthy set of lungs, air is inhaled via your trachea (windpipe) and enters the lungs through two large tubes called thebronchi. The bronchi then branch out, similar to the branches of a tree, into many smaller tubes (bronchioles) that spread throughout the lungs. At the end of the bronchioles are very tiny structures known as alveoli that are actually small air sacs with many tiny blood vessels called capillaries. This is the point of exchange where the oxygen from inhaled air is passed into the bloodstream to be distributed throughout the body, and carbon dioxide is removed from the blood and normally exhaled from the body.
In people with COPD, the respiratory system begins to break down, and both the intake of oxygen and output of carbon dioxide are affected. Inhaling is normally handled by the muscles in your diaphragm and rib cage. These muscles cause your chest cavity to expand, and air is then drawn into the lungs. Exhalation works in a different way, and is a function of the bronchioles and alveoli. When you have chronic bronchitis or emphysema, the bronchioles lose their elasticity, and the alveoli become damaged so that they cannot rid the body of stale air and waste products efficiently. This indirectly affects your ability to inhale fresh air because the lungs are never fully empty due to trapped stale air, and thus have difficulty receiving adequate amounts of oxygenated fresh air. As the disease advances, these two factors continue to work against each other to worsen the overall condition. COPD patients have to work progressively harder to inhale and exhale, and the efficiency of the process of “good air in, and bad air out” deteriorates as well.
The two major conditions that cause the obstructions that lead to COPD are emphysema and chronic bronchitis:
- Emphysema is primarily caused by long-term cigarette smoking, but other factors that irritate the lungs play a role in a small percentage of cases. The constant presence of cigarette smoke actually triggers an excessive response by the body’s immune system that results in the overproduction of substance called elastase. This enzyme produced by the immune system normally works to help fight infections. However, when excessive amounts of it are produced, it leads to the destruction of an important protein in the lung called elastin, which is necessary for keeping the structure of the alveoli walls healthy and functional. Some of these “air sacs” will eventually rupture, while others become abnormally enlarged. The result is that the lungs lose their elasticity, and cannot exhale properly. In addition, the bronchioles tend to collapse due to the higher pressure that must be employed to exhale air from the lungs. This causes stale air to get trapped in alveoli and the lungs, leaving less room for fresh air.
- There is also a rare form of emphysema that is a genetic disorder known as alpha-1-antitrypsin (AAT) deficiency that accounts for a small number (about 1-3%) of COPD cases. It is sometimes called “early onset emphysema,” because it tends to manifest itself in folks as young as 30-40 years of age. This inherited disease afflicts some people who are born with insufficient amounts of AAT, an enzyme inhibitor normally found in the blood. Only about 25% of AAT-deficient persons will ever develop emphysema. This can occur in non-smokers, but the risk for AAT individuals getting COPD is much greater if they smoke.
- Chronic Bronchitis is also a consequence of smoking in the vast majority of cases. While emphysema primarily affects the lower parts of the respiratory tract (bronchioles and alveoli), chronic bronchitis causes the bronchi (the tubes of the upper respiratory tract) to become dysfunctional. The persistent irritation from cigarette smoke or other lung irritants causes the bronchi to become abnormally narrowed, and thus impedes the flow of air. It also stimulates specialized glands that line the bronchi to over-produce mucous, causing further blockage. Folks with chronic bronchitis typically experience an ongoing cough that produces sputum and mucous, and often suffer from shortness of breath as well. Their risk for respiratory infections is increased too, as the smoke damages tiny hair-like structures called cilia that normally sweep the lungs clean of bacteria and other irritants and foreign matter. Many chronic bronchitis patients will go on to develop emphysema as well.
- A subtype of bronchitis called asthmatic bronchitis or bronchial asthma is also sometimes classified in the family of COPD illnesses, but it is not a major cause of COPD. It is a form of chronic bronchitis that is often accompanied by bronchospasms (contractions of the muscles lining the bronchial tubes.) It obstructs the airways and makes respiration more difficult.
- Other than cigarette smoking, there are some additional factors that can increase the risk of developing COPD. These include
- Occupational or residential exposure to industrial pollutants, dust, fumes, or automobile emissions.
- Other types of tobacco use, such as pipes and cigars.
- Age: The risk for chronic bronchitis increases after 40, and that for emphysema after 65.
- Other lung infections or respiratory illnesses will increase the likelihood of a person getting COPD.
- Socioeconomic class: For reasons that are not fully understood, COPD is much more common in blue-collar laborers than in professionals. In fact, the death rate from COPD is about twice as high in unskilled or semiskilled workers.
What Complications Can Occur From COPD?
- Respiratory failure is a dangerous condition that can result from critically low levels of oxygen in the blood, in combination with excessively high levels of carbon dioxide. COPD patients who experience respiratory failure must get medical attention immediately.
- Coronary disease: Individuals with COPD are at increased risk for all kinds of heart disease, including heart attack. The reasons for this are complex, and not understood well.
- Hypertension: COPD can result in high blood pressure, especially in the arteries that are involved in delivering blood to the lungs.
- Lung cancer: The combination of smoking and COPD greatly increases the chances of developing some types of lung cancer.
- Respiratory infections: COPD victims are much more susceptible to all kinds of infections such as colds, pneumonia, or influenza. In turn, these infections can make the COPD much worse and thus increase permanent damage to the lungs.
How is COPD Diagnosed?
There are several common procedures that are used to determine the presence of COPD. These include:
- Pulmonary Function Tests: The purpose of this type of testing is to measure the amount of air your lungs can hold, and how quickly you are able to blow it out and empty your lungs. Spirometry is the most common form of this test. It can be used to detect potential COPD even before there are any noticeable symptoms, and to measure the progression of existing disease as well.
- Arterial blood gas analysis: This very useful blood test measures lung function by determining how well you are able to deliver oxygen and dispose of carbon dioxide via the blood.
- Sputum analysis: Examination of sputum from the lungs can give clues to COPD as well. It can also help to determine if you have certain types of lung cancer.
- Chest x-ray is especially useful at helping determine if you have emphysema or not.
- CT scans are also sometimes recommended, but I would avoid them unless there is a very good and specific reason why you need one. They expose you to high amounts of radiation, typically about 5 times that of an ordinary x-ray.
What Treatments Are Available for COPD?
COPD is a chronic, progressive illness that cannot be cured. The best that one can hope for is to relieve some of the symptoms, and to slow down the advancement of the disease.
Surgery is almost never used due to its high failure rate, and to the fact that most insurance companies do not normally cover it. There are drug therapies that are commonly used, but they have their risks. One common treatment involves the inhalation of corticosteroid drugs, which are typically used in emphysema patients rather than in those with chronic bronchitis.
Two noninvasive treatments that are often very successful are:
- Supplemental oxygen
- Pulmonary Rehabilitation Programs: These programs usually focus on patient education, exercise training, nutritional advice, and counseling that can help patients to manage and cope with the illness better.
COPD is a tragic illness that literally sucks the life out of its victims, and usually leads to an early and painful death. If smokers or potential smokers could only see what awaits them if they don’t stay away from cigarettes, perhaps it would make a positive impact and save many lives.