GALVESTON, Texas Sept. 6, 2012 - New research has shown that the millions of people who use corticosteroids prescribed daily to control mild asthma do no better than those who use them only when symptoms occur.
These findings suggest a potential new treatment option that could change international standards of care, reduce patients' pharmacy costs, limit long-term exposure to corticosteroids and enable flexibility in managing the condition, according to researchers at the University of Texas Medical Branch at Galveston, which led the study. Findings were published in the Sept. 12th issue of the Journal of the American Medical Association.
"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," said lead author Dr. William J. Calhoun, Renfert Professor and Vice Chair for Research in Internal Medicine at UTMB. "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."
Approximately 25 million people in the United States suffer from asthma; the disease costs about $3,300 per person each year in medical expenses, missed days of school and work, and early deaths.
Asthma is an inflammatory disease triggered by a wide range and combination of environmental and genetic factors. The assumption has been that because asthma is always present even if dormant, it should be treated with a continuous dose of anti-inflammatory medications, whether or not symptoms are present.
Accepted protocol is a twice-daily dose of an inhaled corticosteroid (ICS), such as beclomethasone or fluticasone, supplemented with "rescue" doses of albuterol to open the airways during onset of severe symptoms. Under physician-assessment-based adjustment (PABA), the standard of care, doctors adjust ICS dose based on assessment of symptoms, rescue use of albuterol and pulmonary function at six-week intervals.
More than 340 adult patients with mild-to-moderate persistent asthma participated in a randomized trial to assess different strategies for long-term asthma care: PABA; biomarker-based adjustment (BBA), in which a patient's levels of exhaled nitric oxide are monitored on a regular basis; and symptom-based adjustment (SBA), in which inhaled steroid medication is taken only when symptoms occur.
The researchers looked at several outcomes, including bronchial reactivity, lung function, days missed from school/work and exacerbation of symptoms and attacks, for each adjustment regimen over the course of nine months - a timeframe that allowed them to adjust and account for seasonal variations. They found no measurable difference in outcomes among the three treatment methods.
The study also revealed an annual treatment failure rate of roughly 5 percent, with the significant exception of the physician-adjusted model, which doubled to more than 10 percent in the autumn and winter. The researchers believed this was due to a confluence of triggers, including fall allergens, increases in mold or indoor pollution and exposure to viral infections, among other common triggers.
This change in seasonal treatment failure with the physician-adjustment model confirms the need for "temporal personalization," or customized treatment that until now has not been possible. "SBA has the potential to allow us to personalize therapy in real time," Calhoun added. This is a vast improvement over current methods whereby even if a patient regularly sees a physician for reassessment, by the time the medication is adjusted, the patient can be six weeks or more behind the curve.
"There are often several orders of asthma symptom progression before an asthma attack ultimately occurs, resulting in a treatment failure or hospitalization," said co-author Dr. Bill T. Ameredes, Associate Professor, Division of Pulmonary and Critical Care Medicine at UTMB. "Patients using the SBA regimen can treat their symptoms on the spot which may prevent conditions from escalating to a full-blown attack. Further, since ICS have a longer duration of effect, patients will continue to reap the benefits from the initial SBA treatment days later, compared to using just a rescue inhaler."
In addition, the researchers found that good asthma control could be achieved using half the dose of inhaled steroids when the SBA approach was used - providing potential pharmacy cost advantages.
Finally, SBA may also reduce possible risks of long-term use of ICS, including accelerated cataract development, vocal cord weakness and potential endocrine effects, as well as such side effects as mouth and throat irritation and oral yeast infections.
"The current protocol of daily ICS use is effective but the flexibility and immediate probable cost savings for asthma medicine that a symptom-based approach may offer will appeal to many patients," said Calhoun. "We hope our findings prompt patients to talk with their doctors and become more active participants in effectively managing their condition."
About UTMB Health
Established in 1891, Texas' first academic health center comprises four health sciences schools, three institutes for advanced study, a research enterprise that includes one of only two national laboratories dedicated to the safe study of infectious threats to human health, and a health system offering a full range of primary and specialized medical services throughout Galveston County and the Texas Gulf Coast region. UTMB Health is a component of the University of Texas System and a member of the Texas Medical Center.