The use of a combination inhaler containing budesonide and formoterol as both maintenance and quick relief therapy (SMART) has been recommended as an improved method of using inhaled corticosteroid/long-acting beta agonist (ICS/LABA) therapy. Published double-blind trials show that budesonide/formoterol therapy delivered in SMART fashion achieves better asthma outcomes than budesonide monotherapy or lower doses of budesonide/formoterol therapy delivered in constant dosage.
However, it has been reported that only 17% of SMART-treated patients are controlled. In seven trials of 6–12 months duration, patients using SMART:
- used quick reliever daily (average 0.92 inhalations/day)
- awakened with asthma symptoms once every 7–10 days (11.5% of nights)
- suffered asthma symptoms more than half of days (54% of days)
- had a severe exacerbation rate of one in five patients per year (average 0.22 severe exacerbations/patient/year)
These poor outcomes may reflect the recruitment of a skewed patient population.
Although the long-term consequences of SMART therapy have not been studied, its use over 1 year has been associated with significant increases in sputum and biopsy eosinophilia.
At present, there is no evidence that better asthma treatment outcomes can be obtained by moment-to-moment symptom-driven use of ICS/LABA therapy than conventional physician-monitored and adjusted ICS/LABA therapy.
Single maintenance and reliever therapy (SMART) of asthma: a critical appraisal. Thorax 2010;65:747-752 doi:10.1136/thx.2009.128504.
Children with mild persistent asthma should not be treated with rescue albuterol alone - add ICS PRN - Lancet, 2011.
Single inhaler therapy in asthma (SMART) linked to poor day-to-day control of symptoms and increasing inflammation. Clin Exp Allergy. 2012 Jan 18.
Image source: Combination formulation containing budesonide and formoterol - unopened Symbicort Turbuhaler (left) and opened (middle and right), Wikipedia, public domain.