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Asthma
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| Intro: What is asthma? |
| What are the causes of asthma? |
| Who is at risk? |
| Asthma Attacks and Their Triggers |
| How is asthma diagnosed? |
| Treating Asthma |
| Asthma Drugs |
| Ways to Avoid Triggers |
| Other Resources |
More than 14 million Americans suffer from asthma, which is the seventh most common chronic condition in America.[1] Asthma is a chronic lung disease characterized by labored breathing, wheezing, and/or coughing. During an asthmatic episode, bronchial tubes, or airways, become inflamed or swollen due to such triggers as allergies to smoke, dust, and pollen, though why these factors cause asthma is not completely understood. There is no cure for asthma, although it can be effectively controlled with medication and other management strategies. [2] [ To Top ]
The basic cause of asthma is not yet understood. Until the 1970s and early 1980s, asthma was thought to result from over-responsiveness of the tubes (bronchi and bronchioles) that carry air to and from the lungs. People with hypersensitive airways, when exposed to certain irritants called "triggers"-such as household dust, tobacco smoke, cat fur (dander), cockroach droppings, air pollutants, even vigorous exercise or cold air-would experience a "bronchospasm", a narrowing of the airways caused by contraction of the muscles that encircle the bronchial tubes. Asthmatics also tend to produce thick, sticky mucus and have inflamed, damaged airways, both of which make it even more difficult to breathe. [ To Top ]
People with allergies. There is a large correlation between peo allergies and asthma because the irritants for both are so similar.
From the ages of 20 to 50, women outnumber men 3 to 1 in asthma-related hospital admissions. (Interestingly, during childhood, boys outnumber girls for asthma hospital admissions). There is evidence that asthma may be related to a women's hormonal changes and may be triggered just before or during menstruation [3].
Blacks and non-White Hispanics tend to be affected more by asthma. African-Americans are 3 times as likely as Whites to be hospitalized from asthma and 3 times as likely to die from the disease. Although African-Americans make up less than 13 percent of the U.S. population, they account for nearly 22 percent of deaths due to asthma [4].
For reasons that are not well understood, the number of newly diagnosed cases of asthma in the United States is rising sharply, up 58.6 percent between 1982 and 1996. Asthma deaths, too, are climbing--5,434 in 1997 compared with 2,598 in 1979. While not accounting for the rising prevalence of asthma, the lack of necessary health care, especially among the urban poor, may play an important role in the rising asthma death rate. These increases are taking place at a time when some irritants believed to be associated with asthma--such as air pollution, dust, molds, and tobacco smoke-have been identified and efforts are underway to control them. The reason for the increases remains a mystery, but some investigators think one contributing factor is modern, tightly sealed homes and workplaces that trap and re-circulate irritants and contaminants, increasing exposure to them in the air we breathe [5]. [ To Top ]
Acute Asthma Attacks
During an acute attack, asthmatics seem to have a hard time getting their breath. Actually they are struggling to push air out of over-inflated lungs through constricted airways. Since the early 1980s, increasing scientific evidence shows that inflammation is as much responsible for bronchospasms as any other factor. In people with asthma the air passages are continuously inflamed, causing them to be swollen and to react strongly to inhaled irritants. Because patients may not be aware of any symptoms, this inflammation is sometimes called "the quiet part" of asthma. People with chronically inflamed airways may show no outward signs of asthma until the first acute attack requires urgent medical attention, often at a hospital emergency room. Emergency care physicians and nurses--who are all too familiar with acute asthma--are able to administer powerful drugs to open the patient's air passages and restore more normal breathing. They are likely to recommend that you be seen by an asthma specialist, who can devise a combination of treatment and prevention measures aimed at avoiding or minimizing further acute asthma attacks. The first step in that process is an accurate diagnosis [6].
Triggers
People with asthma have airways that are very sensitive to certain things in the environment around us. The stimuli or triggers that cause asthma attacks can vary greatly from person to person. Asthmatic episodes or attacks may be caused by any one or any combination of the following:
This is not a complete list of the factors that may cause an episode of asthma, and something that causes one person to have an attack may not bother a different person. It is important to meet with your doctor to identify your asthmatic triggers so that you can develop a plan to manage your asthma and reduce your exposure to triggers. Some asthma attacks, however, occur without any obvious triggers [7]. [ To Top ]
The diagnosis of asthma is based on repeated, careful measurements of how well you can force air out of your lungs into a machine as well as on a thorough medical history and laboratory tests that pinpoint what triggers asthma attacks [8]. [ To Top ]
Which drugs asthma patients need, when to use them, and how much to use depend largely on the character of their illness, as shown by the degree of breathing impairment and the frequency and severity of acute attacks. Asthma experts agree, however, that the first line of defense is to stay away from whatever brings on an acute asthma episode. Allergen avoidance is one of the best ways to control the asthma.
Anti-allergy medication and allergy desensitization shots are also options. For many of us, triggers are likely to be identified as common allergens or air pollutants. In some asthmatics, attacks can be brought on by strenuous exercise, exposure to cold outdoor air, industrial or household chemicals (cleaning fluids, for example), and food additives such as sulfites. The Flu or even cold viruses can also trigger asthma episodes. In other cases, the triggers cannot be identified, even after a thorough investigation. Knowing what provokes an asthma attack is critically important in preventing more from occurring, but it's often difficult or impractical to avoid contact with triggering irritants. Today, however, physicians can prescribe medications to lessen the risk of acute attacks after exposure to an offending irritant, as well as halt attacks that can't be prevented [9].
The key to effective, long-term treatment of asthma is finding the drugs and dosage plan that are most effective in dealing with or preventing acute episodes for you. While a cure for asthma is not yet available. However, the majority of asthma sufferers can lead essentially normal, symptom-free lives by understanding and sticking to a well-planned strategy to keep clear of asthma triggers and to use the right drugs in the right way [10]. [ To Top ]
The drugs used to treat asthma fall into two broad categories (some fall into both):
Controllers to prevent acute attacks.
Relievers that check acute symptoms when they occur.
Asthma authorities today regard inhaled corticosteroids, sold under numerous brand names, as the most effective agents for controlling airway inflammation and thus preventing acute asthma attacks. Some of the well-known brand names for corticosteroids are:
Other inhaled anti-inflammatory controller drugs include:
A new class of oral anti-inflammatory controller drugs acts by blocking a certain part of the inflammation pathway. This class of "anti-leukotriene" drugs include:
Bronchodilators work to help open the breathing tubes (bronchi), but do not treat the underlying inflammation. There are both short-acting and long-acting bronchodilators. Long-acting inhaled and oral bronchodilators) are often used in conjunction with anti-inflammatory agents to control symptoms. They don't provide immediate relief of symptoms, but their preventive action lasts for many hours, which makes them useful in controlling attacks that might occur when you sleep. Some examples of these brochodilators are:
Drugs to bring quick relief in acute asthma attacks are chiefly short-acting inhaled bronchodilators that act rapidly, but for a relatively brief time, to relax bronchial constriction. There are many short-acting bronchodilators to choose from, including:
Although these drugs are effective in treating asthma, there is some controversy about their safety, especially when they are overused. It is clear, however, that an increasing need for inhaled bronchodilators (or a decreasing response to each dose) is a signal that the patient's asthma is not being adequately controlled. If you are having an increasing need for short-acting inhaled bronchodilators, please contact your physician for drug reevaluation.
Both prescription and over-the-counter (OTC) short-acting bronchodilators are available. Like the prescription drugs, the OTC drugs act only to provide symptom relief, and they are generally effective for a shorter period. They may be useful, therefore, as temporary treatment for mild asthma attacks. Ready availability in drugstores makes the OTC products potentially helpful as a "stopgap" for those with asthma who do not have their prescription medication at hand when an asthma attack occurs. More importantly, if you are using an OTC inhaler, you should still seek advice from a health professional about the long-term treatment of your asthma [11]. [ To Top ]
[1] http://www.nhlbi.nih.gov/health/public/lung
[2]Adapted from http://www.4woman.gov/faq/asthma.htm
[3]Adapted from http://www.4woman.gov/faq/asthma.htm
[4]Adapted from http://www.fda.gov/fdac/features/996_asth.html
[5]Adapted from http://www.fda.gov/fdac/features/996_asth.html
[6]Adapted from http://www.fda.gov/fdac/features/996_asth.html
[7]Adapted from http://www.4woman.gov/faq/asthma.htm
[8]Adapted from http://www.fda.gov/fdac/features/996_asth.html
[9]Adapted from http://www.fda.gov/fdac/features/996_asth.html
[10]Adapted from http://www.fda.gov/fdac/features/996_asth.html
[11]Adapted from http://www.fda.gov/fdac/features/996_asth.html
[12]Adapted from http://www.4woman.gov/faq/asthma.htm
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