Hershey, Pa. -- The major study of mild asthma reported in the September 19 issue of the New England Journal of Medicine ends a five-year debate about appropriate use of medication for treating mild asthma.
The results show that the commonly prescribed inhalant drug, albuterol, should be used only on an as-needed basis for patients with mild asthma. Regularly scheduled use of albuterol is not risky, but neither is it necessary, according to co-investigator Clifford W. Zwillich, M. D., professor and chief of pulmonary and critical care at Penn State's Milton S. Hershey Medical Center.
Puffing on the inhalant only during an attack of coughing or wheezing is sufficient for mild asthmatics, according to Zwillich. Data collection and statistical analysis for the multi-center study was designed and managed by Vernon M. Chinchilli, Ph.D., of the Center for Biostatistics and Epidemiology at Hershey.
Many of the more than 7 million Americans with mild asthma take albuterol as a regular medication. The inhalant is a beta-agonist that relaxes smooth muscles of the airways. It is sold under the brand names of Ventolin and Proventil.
The study also demonstrates that asthma patients continue to have a good response to inhaled beta-agonists, even after months of daily use, contrary to earlier reports.
Principal investigator Vernon M. Chinchilli, Ph.D., professor of biostatistics at Hershey, masterminded the design for collection, management and analysis of the data from patients at five medical centers. The work was coordinated by his team of researchers at the Asthma Clinical Research Network (ACRN) Data Coordinating Center (DCC) based at Hershey's Center for Biostatistics. ACRN is funded by the National Heart, Lung and Blood Institute (NHLBI).
The results of the study were reported in the article, "Comparison of Regularly Scheduled with As-Needed Use of Albuterol in Mild Asthma," in the September 19 issue of the New England Journal of Medicine, authored by Jeffrey M. Drazen, M.D., and Elliot Israel, M.D., both of Brigham and Women's Hospital and Harvard Medical School.
"When you design a big trial like this, somebody has to be the central data bank," said Drazen. "Hershey was our bank and without them we would have been buried under an avalanche of data."
"Each patient's data must be kept separate," said Drazen. "All of the people involved in the study must remain uninformed of the preliminary results, so as not to bias the collection of the data. And when the huge mound of data is collected, the statisticians must distill out the results very quickly. The DCC at Hershey did an outstanding job. They cleaned up and analyzed the data very quickly."
The study speaks to the concerns of more than 7 million Americans with mild asthma -- and their physicians -- about the safety and effectiveness of inhaled beta-agonists, according to NHLBI director Claude Lenfant, M.D. Patients with only occasional asthma symptoms need not take medication regularly, he said.
"Since more than half of the asthma patients in this country have mild asthma, this study should result in a substantial decrease in the overall cost of asthma care," he added.
According to the NHLBI, asthma affects more than 13 million Americans. The frequency, severity of illness, and death rate from the disease have been increasing steadily for more than a decade. Asthma also is a major cause of lost wages and school absenteeism, resulting in estimated annual health care costs of more than $4.6 billion.
Prior to 1990 most asthma experts believed that prescribing beta-agonists on a regularly scheduled basis improved overall control of asthma symptoms. Several studies since then have suggested that regular beta-agonist use might induce tolerance or even adverse effects, leading to diminished control of asthma in some patients, and some hypothesized that this could account for the increasing asthma severity, hospitalization and death rates seen world-wide. These studies included patients with moderate, as well as mild, asthma who were using beta-agonists along with other asthma medications.
Chinchilli said the sample size of 255 patients with mild asthma from five participating medical centers is sufficient for the conclusions drawn from the data. He said the data are of the highest quality, due to extremely rigorous research methods employed in all aspects of the 26-week randomized, double-blind, placebo-controlled study.
Clinical coordinators at each of the study locations were able to enter data over the Internet using an online form. The data were then verified by data managers at Hershey. In addition to keeping a daily record of symptoms, 10 to 16 pages of data were produced for all 255 patients on each of 12 hospital visits.
After a 6-week evaluation period, patients were randomized to receive either the inhaled beta-agonist, albuterol, two puffs four times a day, or an identical-appearing placebo inhaler for 16 weeks. Patients in both groups were permitted to take additional albuterol, when needed, for relief of asthma symptoms. During a final four-week withdrawal period, all patients received only as-needed albuterol.
The study showed that even though the average use of albuterol was five times higher in the regular use group than in the as-needed group, there were no significant differences between the two groups in measures of lung function, asthma symptoms, or quality of life that could be attributed to the treatment. Although a few differences between the two groups could be attributed to the treatment, the effects were small and deemed to be clinically unimportant.
Asthma Clinical Research Network (ACRN) was created in 1993 by the NHLBI as a five-year program to expedite design and implementation of clinical trials on approaches to managing asthma. The albuterol and placebo for the beta-agonist study were donated by Schering-Plough, headquartered in Kenilworth, N.J.
Hershey served as the data coordinating center for the study which was conducted by investigators from Brigham and Women's Hospital, Boston; National Jewish Center for Immunology and Respiratory Medicine, Denver; University of Wisconsin, Madison; Thomas Jefferson University, Philadelphia; University of California, San Francisco. A sixth center at Harlem Hospital in New York was added to the Asthma Clinical Research Network in 1995.
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Deborah S. Saline (o) (717) 531-8606