Asthma patients should use ICS-LABA for rescue as well as maintenance, SMART says
In Europe, patients with asthma have long been advised to take more puffs of their combination inhaled corticosteroid-long-acting beta-agonist (ICS-LABA) inhaler during periods of increased asthma symptoms. In the U.S., patients are instead advised to use albuterol as their rescue inhaler, and stick firmly to the usual maintenance dose of ICS-LABA regardless of symptom severity.
A potentially practice-changing meta-analysis of 16 randomized trials showed the European method of boosted dosing during symptomatic periods -- dubbed the SMART strategy in the analysis -- was superior to the U.S.'s consistent-dosing approach.
Patients using ICS-LABA as a rescue as well as maintenance inhaler treatment experienced significantly fewer asthma exacerbations, hospitalizations, and emergency department visits, compared to those using ICS-LABA for maintenance and albuterol for rescue. The findings were reported in JAMA.
The SMART trials enrolled 22,500 patients total (almost all adults). Those using the ICS-LABA (budesonide-formoterol) as maintenance + rescue strategy had a 32% fewer asthma exacerbations compared to patients taking an equivalent dose of ICS-LABA who used albuterol as rescue.
More impressive, the patients in the budesonide/formoterol maintenance + rescue arm had 23% fewer exacerbations than patients taking higher doses of ICS-LABA as maintenance therapy, who used albuterol as rescue. The SMART strategy was also superior to ICS monotherapy as maintenance, with albuterol as rescue.
The benefits of ICS-LABA as rescue-plus-maintenance were even larger in children aged 4-11 years, with roughly 50% reductions in exacerbations compared to conventional strategies.
The SMART analysis was in contrast to recent studies published in NEJM showing that increasing inhaled steroids alone was an ineffective way of aborting asthma exacerbations in children or adults.
One small caveat was that the ICS-LABA used in the studies was a dry powder; in the U.S., this specific ICS-LABA preparation (budesonide-formoterol) is an aerosolized metered dose inhaler sold as Symbicort. Implementation of the SMART strategy in the U.S. would result in patients burning through their ICS-LABA controller inhalers (e.g., Advair, Symbicort, Dulera, et al) at an increased and unpredictable rate, confounding pharmacists and insurers.
Current U.S. asthma guidelines are more than a decade old, and experts predicted a major revision which will incorporate the SMART strategy and also endorse long-acting muscarinic antagonist (LAMA) use as an adjunctive therapy to inhaled steroids for asthma maintenance.