of someone--a child or an adult--racked by uncontrolled coughing.
With a heaving, distended chest, neck muscles straining, and eyes
showing alarm verging on panic, the person can utter only a few
brief words between rasping, wheezing, frantic efforts to breathe.
person puts a tube like device in his or her mouth and inhales twice.
Within minutes, remarkably it seems, the crisis is over. Breathing
returns to normal. The person can go back to school or work or even
jogging--until the next attack, which might be hours or months away.
attacks are often milder than this description--just a shortness
of breath that soon passes without treatment. But they can also
be much, much worse, requiring a hurried trip to the hospital for
emergency--sometimes lifesaving--care. Even in severe cases, hospital
treatment usually enables asthma patients to regain near-normal
breathing. But not always. Almost 5,000 asthma deaths were reported
in the United States in 1992, according to the American
Lung Association (1992 is the most recent year for which statistics
are available). Most of the deaths occurred in patients who misjudged
the severity of symptoms or failed to reach a hospital or clinic
in time to prevent respiratory failure.
African-Americans make up approximately 12 percent of the U.S. population,
they account for 21 percent of deaths due to asthma, according to
the American Lung Association.
reasons that are not well understood, the number of newly diagnosed
cases of asthma in the United States is rising sharply, up 56.7
percent between 1982 and 1992. Asthma deaths, too, are climbing--4,964
in 1992 compared with 2,598 in 1979. Lack of necessary health care,
especially among the urban poor, is thought to play an important
role in the rising asthma death rate.
these increases are taking place at a time when some things believed
to be associated with asthma--such as air pollution, dust, molds,
and tobacco smoke--are better understood and often under better
control than they once were. 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 recirculate
contaminants, increasing exposure to them in the air we breathe.
of America's 12 million to 14 million people with asthma, of whom
more than 4 million are under age 18, have a relatively mild illness.
About a quarter of asthmatic children seem to "outgrow" their disease
in their teen years or as young adults. It's not certain, however,
that they are completely free of asthma. Studies of people with
late-onset asthma--asthma that first shows up in the fifth or sixth
decade of life or even later--have found that many of them experienced
asthma-like breathing difficulties as children.
is no known cure, but most asthma can be controlled by a strategy
aimed at preventing acute episodes and halting those that do occur.
two-pronged attack is increasingly effective because scientists
are piecing together a more comprehensive picture of the nature
of asthma and gaining new insights into the cause, prevention and
management of acute asthma attacks. New information is changing
the way practicing physicians and the Food and Drug Administration
view the role of drugs in asthma treatment and prevention.
the 1970s and early 1980s, asthma was understood 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
"bronchospasm," a narrowing of the airways caused by contraction
of the muscles that encircle the bronchial tubes.
also tend to produce thick, sticky mucus and have inflamed, damaged
airways, both of which worsen the breathing restriction caused by
bronchospasm. (This is illustrated in a 42K
PDF file.) 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.
understanding of asthma led to treatments aimed primarily at opening
up the bronchial tubes by using drugs that cause the bronchial muscles
to relax their grip on air passages. Bronchodilators are still a
mainstay of asthma therapy. But Robert Meyer, M.D., of FDA's Center
for Drug Evaluation and Research, notes that scientists' understanding
of asthma has changed significantly over the last decade or so.
points out that since the early 1980s, increasing scientific evidence
shows that inflammation is as much responsible for bronchospasm
as anything else. Today, Meyer says, "putting primary emphasis on
controlling bronchospasm rather than chronic airway inflammation
"looks like putting the cart before the horse."
evidence Meyer refers to strongly indicates that asthma is a chronic
inflammatory disease that usually develops within the first few
years of life. Much of this evidence is discussed by H.W. Kelly
of the University of New Mexico College of Pharmacy in the October
1992 issue of the Journal of Clinical Pharmacology and Therapeutics,
people with asthma, whether mild or severe--even in asthmatics whose
first acute attack occurs long after childhood--the air passages
are continuously inflamed, causing them to be swollen and to react
strongly to inhaled irritants. But because patients may not be aware
of any symptoms, this inflammation is sometimes called "the quiet
part" of asthma.
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 department. 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 virtually normal breathing. They are likely to recommend
the patient 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.
diagnosis of asthma is based on repeated, careful measurements of
how efficiently the patient can force air out of the lungs and on
a thorough medical history and laboratory tests to find out what
"triggers" the patient's acute attacks.
with asthma react to external irritants in a way that non-asthmatics
don't. Many but not all asthmatics have allergies that cause their
bodies to produce an abnormal array of chemicals in response to
environmental allergens. In that sense, asthma is akin to pollen
allergies, hives, and eczema. But in asthma, the allergic reaction
contributes to inflammation of the airways rather than of skin,
eyes, or nose and throat. An acute asthma attack may come on rapidly
after exposure to an irritant or develop slowly over several days
or weeks, which can complicate the job of identifying a patient's
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 avoidance of whatever brings on an acute asthma episode.
Though for most patients "triggers"--there are often more than one--are
likely to be 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. In other cases,
the triggers cannot be identified, even after a thorough investigation.
what provokes an asthma attack is critically important in prevention,
but it's often difficult or impractical to avoid contact with triggering
irritants. Today, however, physicians can prescribe drugs to lessen
the risk of acute attacks after exposure to an offending irritant,
as well as halt attacks that can't be prevented.
drugs used to treat asthma fall into two broad categories: controllers
to prevent acute attacks and relievers that check acute symptoms
when they occur. Some drugs do both.
light of mounting evidence that asthma is fundamentally an inflammatory
disease, asthma authorities today regard inhaled corticosteroids--marketed
under numerous brand names, including Aerobid, Azmacort, Vanceril,
Flovent and Pulmicovt--as the most effective agents for controlling
airway inflammation and thus preventing acute asthma attacks. Corticosteroids
in pill or tablet form (such as Medrol) and in liquid form for children
(such as Pediapred and Prelone) are prescribed for some patients
with severe asthma.
inhaled anti-inflammatory controller drugs include Intal (cromolyn
sodium), which is useful in preventing asthma brought on by exercise,
and Tilade (nedrocromil sodium).
class of oral anti-inflammatory controller drugs acts by blocking
a certain part of the inflammation pathway. This class of "anti-leukotriene"
drugs include Zyflo (zileuton), Accolate (zafirlukast) and Singulair
(montelukast). Long-acting inhaled bronchodilators, such as Serevent
(salmeterol), and long-acting oral bronchodilators, such as Alupent
(metaproterenol), Proventil (albuterol sulfate), Theo-24 (theophylline
anhydrous), and many others, are often used in conjunction with
anti-inflammatory agents to control symptoms. They don't provide
immediate relief of symptoms, but their preventive action persists
for many hours, which makes them useful in controlling attacks that
might occur during hours of sleep.
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 chose from, including Alupent or Metaprel (metaproterenol),
Brethaire (terbutaline), and Ventolin or Proventil (albuterol).
Although these drugs are effective in treating asthma, there is
some controversy about their safety, especially when they are overused.
Scientific debate makes it 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.
Patients who have an increasing need for short-acting inhaled bronchodilators
should be reevaluated promptly by their physicians.
prescription and over-the-counter (OTC) short-acting bronchodilators
are available. The OTC drugs generally contain lesser amounts of
the active agent than prescription forms and are effective for a
shorter period. They may be useful, however, as temporary treatment
for mild asthma attacks. Ready availability in drugstores makes
the OTC products potentially helpful as a "stopgap" for patients
who do not have their prescription medication at hand when an asthma
attack occurs. However, patients who use OTC inhalers should still
seek advice from a health professional about the long-term treatment
of their asthma.
key to effective, long-term treatment of asthma is finding the drugs
and dosage plan most effective in dealing with or preventing acute
episodes. But effective treatment depends as well on the patient
and the care-giver knowing what the various anti-asthma drugs do,
when and in what amount each drug should be used, when a change
in symptoms or in the response to a particular drug requires a call
or visit to the physician, and when to get emergency help. Physicians
who specialize in treating asthmatics go over these points in detail
as part of an overall treatment plan designed and, as necessary,
adjusted to meet needs of each individual patient.
for asthma is judged by experts to be still a far-off possibility.
But 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.
It isn't easy, but it works.
Flieger is a writer in Washington, D.C.
Consumer magazine (November 1996)