As-Needed Treatment for Patients With Mild Persistent Asthma
Findings from the 2005 Improving Asthma Control Trial, or IMPACT, (Homer A. Boushey, M.D. et al. Daily versus As-Needed Corticosteroids for Mild Persistent Asthma) comparing treatment methods for patients with mild persistent asthma suggests a new standard of care that forgoes the need for daily therapy. Investigators analyzed patients’ pharmacy records and noticed that even though accepted treatment guidelines suggested daily use of anti-inflammatory therapy, patients with mild persistent asthma prescribed this method rarely renewed their prescriptions for asthma controller medications. This finding prompted an investigation into difference in outcomes between patients who used daily therapy compared to those who followed a “symptom-based action plan” that called for brief spurts of corticosteroid treatment “as-needed,” only when symptoms worsened.
Patients were analyzed for inclusion in the study based on smoking status, FEV1 at baseline (FEV1 measures the maximum volume of air expired in one minute which required at least 70% of expected for a patient enrolled in the study), and recent hospitalizations, infections, and corticosteroid use. Study subjects needed to display non-severe symptoms and been willing and able to keep a diary of asthma-related quality of life categories as well as records of PEF measurements. Change in PEF measurements (PEF, or peak expiratory flow, measures the speed of airflow through the bronchi) was the primary measure of outcome for each treatment.
Three treatment groups were examined and compared, each enrolling about 70 mild persistent asthma patients. One group was prescribed an “intermittent short-course treatment,” which consisted of daily placebo pills and placebo inhalers. A second group was given a placebo inhaler and twice-daily tablet form of zafirlukast, a leukotriene receptor antagonist The third group was given a placebo pill and twice daily treatment with budesonide, an inhaled corticosteroid. Each group’s treatment instructions were supplemented with a labeled budesonide inhaler and prednisone tablets for use in case of asthma exacerbations.
The study found no significant difference in outcome between the three methods according to the primary analysis factor, morning PEF. Though the study did find some advantages in quality of life categories and airway biology within the budesonide group, the differences were not extraordinary. In fact, the intermittent treatment group following a symptom-based plan only used supplemental corticosteroid treatment for an average of 3.5 days out of the study year, which did not differ greatly from the supplemental use within the other groups. Another promising finding was a relatively consistent rate of exacerbations across all three groups. Other long-term studies of daily therapy with budesonide suggest that it has the effect of slowing airway deterioration over time, however, given the subjects’ age and the length of the study, exploration of this question was outside the scope of the project.
These IMPACT findings imply that intermittent therapy in addition to being more convenient and cost effective for patients, are just as effective when exacerbation therapy really counts, during times when symptoms are more severe. This helps resolve the controversy over treating adult mild-persistent patients like their child-age counterparts. Adult patients with mild-persistent asthma may experience only 2 exacerbations per year, if any at all. Yet they are prescribed the same treatment as childhood mild-persistent sufferers who experience much more frequent exacerbations. It makes sense, then, to offer an alternate therapy, grounded in the reality of patient compliance that also demonstrates equal effectiveness at lower financial cost. Furthermore, intermittent treatment may overcome some of the drawbacks and side effects of daily therapy, lowering patients’ quality of life costs. As can be seen in other studies, like the 2009 SARA article we tried to find?--- “as-needed” ought to be the new standard of care for mild persistent asthma.
About the Drugs:
Inhaled Corticosteroids: (QVAR, PULMICORT, SYMBICORT, ALVESCO, FLOVENT, ADVAIR, ASMANEX) Considered the most effective long-term usage medication for control and management of asthma. Work by anti-inflammatory action, inhibiting activation of immune cells and lowering vascular permeability in response to allergen.
Oral/Systemic Corticosteroids: (prednisone) Used for acute asthma exacerbations and chronic severe asthma. Usually dose is promptly tapered off when symptoms are under control because of adverse effects of long-term use. Prednisone works by anti-inflammatory action, inhibiting activation of immune cells and lowering vascular permeability in response to allergen.
Leukotriene Receptor Antagonist: (ACCOLATE, SINGULAIR) Occasionally prescribed for management of mild asthma. These drugs work by competitively inhibiting leukotriene action as a bronchoconstrictor.
As-Needed Treatment for Asthma:
Many patients are already doing this, but is it effective and is it safe?