NHLBI STUDY SUGGESTS SYMPTOM-DRIVEN THERAPY
MAY BE SUFFICIENT FOR SOME ADULTS WITH MILD PERSISTENT
ASTHMA
Some adults with mild persistent asthma may be able
to adequately control their asthma by taking corticosteroids
only when needed, instead of taking anti-inflammatory
medication daily, according to new results from the
Improving Asthma Control Trial (IMPACT). Conducted
by the National Heart, Lung, and Blood Institute’s
(NHLBI) Asthma Clinical Research Network, the one-year,
multi-center study found that participants who were
treated with corticosteroids intermittently based
on symptoms had about the same rate of severe exacerbations
and of asthma-related lung function decline as those
treated with the standard recommendation of daily
long-term control medication.
Asthma is considered mild and persistent when individuals
have acute symptoms such as wheezing, coughing, or
chest tightness more than twice a week, but not daily,
or they have night-time awakenings due to asthma more
than two nights a month. The researchers caution that
the new findings might not apply to people who have
recently developed asthma. In addition, they do not
apply to patients with more frequent symptoms or more
severe asthma. The results are published in the April
14 issue of the New England Journal of Medicine.
“This study provides evidence of another possible
way to treat adults with long-standing mild persistent
asthma,” stated Elizabeth G. Nabel, MD, director
of the NHLBI, part of the National Institutes of Health.
“If additional research confirms these findings,
then some of these patients may be able to safely
treat their asthma with intermittent medication and
avoid the added expense and inconvenience of daily
therapy. As for all asthma patients, however, individuals
should work closely with their healthcare providers
to develop and follow the treatment plan that suits
them best.”
More than 20 million Americans have asthma. For those
with mild persistent asthma, guidelines from the National
Asthma Education and Prevention Program (NAEPP) currently
recommend daily long-term control medication to prevent
symptoms and quick-relief medication (inhaled bronchodilator)
to treat acute asthma symptoms if they occur.
The recommendation for daily long-term control medication
for mild persistent asthma was based largely on clinical
trials that showed that anti-inflammatory therapy
improves lung function and measures of asthma control.
However, participants in these earlier studies had
asthma that ranged in severity from mild to moderate,
according to the IMPACT authors. The IMPACT study
strictly adhered to the guidelines’ definition.
James Kiley, PhD, director of the NHLBI Division of
Lung Diseases, commented, “By focusing exclusively
on mild persistent asthma, the IMPACT study has added
to our understanding of possible treatment options
for different levels of asthma severity.”
NAEPP is expected to release updated guidelines in
2006. An expert panel will consider the results of
IMPACT and other studies to determine if changes in
treatment recommendations for adults with mild persistent
asthma are warranted.
IMPACT was designed to identify the best long-term
treatment strategy for adults with mild persistent
asthma. Researchers compared changes in lung function,
frequency and severity of asthma symptoms, and quality-of-life
scores in 255 adult patients. Participants were randomly
selected to one of three treatment groups. Two groups
were assigned to long-term control medication taken
twice daily -- either an inhaled steroid (budesonide)
or a leukotriene modifier (zafirlukast) taken in pill
form. The third group received placebo (inactive)
medication. All participants were given medications
for asthma symptoms -- inhaled bronchodilator (albuterol),
inhaled corticosteroid (budesonide), and oral corticosteroid
(prednisone) -- with explicit instructions on when
and how to use these treatments depending on the severity
and duration of the individual’s symptoms.
After one year, changes in lung function and the number
of severe attacks did not significantly differ among
the three groups. In addition, participants scored
similarly on quality-of-life tests regardless of treatment
group. Those in the daily inhaled steroid group, however,
reported significantly more symptom-free days (equivalent
to about 26 additional symptom-free days per year)
than participants in the other two treatment groups.
“Although some reports of symptoms differed between
those taking budesonide daily and the other participants,
these differences were not reflected in the quality-of-life
scores,” noted Homer Boushey, M.D., Principal
Investigator at the University of California San Francisco,
and a lead author of the study. “Combined with
the fact that there were no significant differences
in lung function changes or in the frequency of severe
attacks among the treatment groups after a year of
treatment, we conclude that, overall, the three treatments
had similar clinical effects in this study of mild
asthma.”
Other reports have noted that many asthma patients
do not follow recommendations for daily controller
medication. “The results of IMPACT suggest that
for some adults with long- standing mild persistent
asthma, choosing not to take daily medications might
be okay,” added Elliot Israel, M.D., Principal
Investigator at Brigham and Women's Hospital in Boston
and the co-lead author. “But this choice should
be made in consultation with the patient’s healthcare
provider. It’s critical that individuals with
more severe asthma follow recommendations for daily
long-term control medications and that all asthma
patients -- even those with mild asthma -- be aware
of signs of worsening asthma and adequately treat
their symptoms.”
Asthma treatment guidelines also recommend written
action plans as part of an overall effort to educate
patients in self-management. The plans provide guidance
for patients on how to monitor and treat their asthma,
including how to recognize when their condition worsens.
In general, action plans are based on the patient’s
symptoms or on “peak flow” measurements
of lung function, which can be taken by patients using
a hand-held device.
“One of the most important things we did during
this study was to work closely with the participants
to help them effectively manage their asthma,”
noted Boushey. “Patients need to know how to
recognize asthma symptoms, what to do when symptoms
begin, and -- perhaps most essential -- they must
have at hand the means to treat their symptoms quickly.”
Clinical centers for the Improving Asthma Control Trial
were
- Brigham and Women's Hospital and Harvard Medical
School, Boston, MA
- Columbia Presbyterian Medical Center and Harlem
Lung Center, New York, NY
- National Jewish Medical and Research Center,
Denver, CO
- University of Wisconsin, Madison
- Thomas Jefferson Medical College, Philadelphia,
PA
- University of California, San Francisco
The data coordinating center is at Penn State College
of Medicine, Penn State Milton S. Hershey Medical
Center, Hershey, PA.
The medications for IMPACT were donated by Astra-Zeneca
Pharmaceuticals, headquartered in Wayne, Pennsylvania.
To interview an NHLBI expert, please contact the NHLBI
Communications Office at (301) 496-4236. To interview
Dr. Boushey, please contact Wallace Ravven, at the
University of California, San Francisco Department
of Public Affairs at 415-476-2557. To interview Dr.
Israel, please contact Melanie Franco at the Brigham
and Women’s Hospital Department of Public Affairs
at (617) 534-1600.
NHLBI is part of the National Institutes of Health
(NIH), the Federal Government's primary agency for
biomedical and behavioral research. NIH is a component
of the U.S. Department of Health and Human Services.
Additional information about asthma and other NHLBI-supported
research and educational programs are available online
at the NHLBI website, www.nhlbi.nih.gov.
Resources
• Guidelines for the Diagnosis and Management
of Asthma —Update on Selected Topics 2002, http://www.nhlbi.nih.gov/guidelines/asthma/index.htm
• National Asthma Education and Prevention Program,
http://www.nhlbi.nih.gov/about/naepp/index.htm
• Asthma Information for Patients and the General
Public, http://www.nhlbi.nih.gov/health/public/lung/index.htm
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