Single maintenance and reliever therapy (SMART) of asthma: a critical appraisal
- 1Asthma and Airway Centre, University Health Network, Toronto Western Hospital, Toronto, Ontario, Canada
- 2Department of Respiratory Medicine, London Chest Hospital, London, UK
- 3Respiratory Unit, Western General Hospital, Edinburgh, UK
- 4Department of Respiratory Medicine, St George's, University of London, London, UK
- 5Pediatric Research Unit, Kolding Hospital, Kolding, Denmark
- Correspondence to Kenneth R Chapman, Asthma and Airway Centre, University Health Network, Toronto Western Hospital, Room 7-451 East Wing, 399 Bathurst St, Toronto, Ontario M5T 2S8, Canada;
- Received 30 October 2009
- Accepted 28 February 2010
- Published Online First 27 June 2010
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 β 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. Attempts to compare budesonide/formoterol SMART therapy with regular combination ICS/LABA dosing using other compounds have been confounded by a lack of blinding and unspecified dose adjustment strategies. The asthma control outcomes in SMART-treated patients are poor; it has been reported that only 17.1% of SMART-treated patients are controlled. In seven trials of 6–12 months duration, patients using SMART have used quick reliever daily (weighted average 0.92 inhalations/day), have awakened with asthma symptoms once every 7–10 days (weighted average 11.5% of nights), have suffered asthma symptoms more than half of days (weighted average 54.0% of days) and have had a severe exacerbation rate of one in five patients per year (weighted average 0.22 severe exacerbations/patient/year). These poor outcomes may reflect the recruitment of a skewed patient population. Although improvement from baseline has been attributed to these patients receiving additional ICS therapy at pivotal times, electronic monitoring has not been used to test this hypothesis nor the equally plausible hypothesis that patients who are non-compliant with maintenance medication have used budesonide/formoterol as needed for self-treatment of exacerbations. 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.
- asthma control
- study design
- asthma guidelines
- asthma pharmacology
- perception of asthma/breathlessness
Competing interests In the past 3 years, KRC has received compensation for consulting with AstraZeneca, Boehringer-Ingelheim, CSL Behring, GlaxoSmithKline, Merck Frosst, Novartis, Nycomed, Pfizer, Roche, Schering Plough and Telacris; has undertaken research funded by AstraZeneca, Boehringer-Ingelheim, CSL Behring, Forest Labs, GlaxoSmithKline, Novartis, Parangenix, Roche and Talecris; and has participated in continuing medical education activities sponsored in whole or in part by AstraZeneca, Boehringer-Ingelheim, GlaxoSmithKline, Merck Frosst, Novartis, Nycomed, Pfizer and Talecris. NCB has lectured for or received consulting fees from GlaxoSmithKline, AstraZeneca, Altana, Merck Generics, Chiesi and TEVA and has received grant support from GlaxoSmithKline and AstraZeneca. In the past year APG has received lecture fees from AstraZeneca and GlaxoSmithKline. PWJ has received consultancy fees from GlaxoSmithKline, AstraZeneca, Almirall, Boehringer-Ingelheim and Spiration; has received lecture fees from GlaxoSmithKline; and his institution will from his time as a consultant to Novartis. Within the past 3 years, SP has received compensation for consulting with Nycomed, GlaxoSmithKline, Neolab and AstraZeneca and has given lectures sponsored by Nycomed and GlaxoSmithKline. This manuscript was conceived, researched and written by the authors without assistance from employees of the pharmaceutical industry or their agents. No professional writers participated in the preparation of the manuscript.
Provenance and peer review Not commissioned; externally peer reviewed.
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