(RxWiki News) Sometimes inhalers are puffed once a day for asthma. Other times it's done only when it's difficult to breathe. Is one way better than another?
A new study on treatments for asthma found that taking corticosteroids daily works no better than using them only when symptoms occur.
"Ask your doctor which asthma treatment is right for you."
More than 340 patients with mild-to-moderate asthma were included in the study led by William Calhoun, MD, a Renfert professor and vice chair for research in Internal Medicine at the University of Texas Medical Branch at Galveston.
Participants were randomly assigned to one of three groups to receive a different asthma treatment.
They were instructed to take their asthma treatment over a nine-month period between June 2007 and July 2010 to allow researchers to study whether the changing seasons affected the results.
In the first method, doctors change patients' corticosteroid dosage based on their symptoms and lung function.
The second method checks patients' levels of nitric oxide levels as they breathe out.
For each of the patients in the three groups, researchers looked at how well their lungs worked, what was happening inside their lungs, the number of days missed from school or work, and any symptoms and attacks that got worse over a nine month period.
They found that there is no measurable difference in how the three methods affected these outcomes.
Participants lost few days from work and school during the study, but the chance of missing school and work was twice as high among those given the second treatment compared to the third.
Difficulties breathing more often than normal, as well as having multiple asthma attacks, did not differ among the treatment groups.
The proportion of treatments that didn't work and led to more serious asthma conditions also did not differ among the treatments.
And overall, the treatments didn't work about 5 percent of the time.
However, the treatment that involves changing the medication dosage failed more than 10 percent of the time during autumn and winter months.
The authors said this was because of multiple reasons, including fall allergies, increases in mold and indoor pollution, and exposure to viruses.
Since the treatment isn't as effective with the change in seasons, the researchers say there's a need for "'temporal personalization,' or customized treatment that until now has not been possible.'"
"The discovery that these two courses of treatment do not differ significantly could eventually change the way doctors and patients manage asthma, providing an option that is easier to follow and possibly less expensive," Dr. Calhoun said.
"Our findings build on a considerable foundation of research in the field and come at a time when asthma cases are rising at an alarming rate – especially in lower-income communities."
They also found that good asthma control could happen using half the dose of inhaled steroids when using the third method.
The symptoms-based treatment may also lessen the possible side effects that come with long-term inhaler usage, the authors said. This includes cataract development, vocal cord weakness, mouth and throat irritation, and oral yeast infections.
"Symptom-based adjustment strategies are appealing because they are simple to use and empower patients," the authors said in their report.
"Whether these features might improve adherence to therapy was not testable in this closely monitored trial."
The authors note several limitations with their study, including having a small sample size and that testing patients in a controlled setting may not be as similar to real-life practice.
Funding for the study came from the support of the Institute for Translational Sciences at UTMB and awards and grants from the National Institutes of Health and National Heart, Lung, and Blood Institute. Teva Pharmaceuticals provided the study drugs and placebo.
Several of the authors received funding and served on a number of committees that may be a conflict of interest in the study, including the National Heart, Lung and Blood Institute.
The study was published Sept. 12 in the Journal of the American Medical Association.