Abstract
Rationale: Long-acting b2-agonists (LABA) and leukotriene receptor antagonists (LTRA) are two recommended agents to add to inhaled corticosteroids (ICS) in asthma patients not adequately controlled by ICS alone. Conflict studies exist on whether the Arg16Gly genotype in b2-adrenergic receptor (ADRB2) gene may influence the bronchodilator effect of b2-agonists, and some indicate that subjects with Arg/Arg show deterioration in pulmonary function with long-term LABA treatment.
Objective: We hypothesized that the Arg16Gly genotype might determine the differential response to either LABA (salmeterol, Sal) or LTRA (montelukast, Mon) when added to ICS in patients with asthma.
Methods: This study was a randomized, cross-over design and 62 mild to moderate asthma patients (26 patients with Arg/Arg, 36 patients with Gly/Gly) were enrolled. The primary endpoint was a difference of the change in the morning PEF at 16 weeks [ΔPEF (Sal) – ΔPEF (Mon)] between the two genotypes.
Results and Conclusion: The mean difference in [ΔPEF (Sal) – ΔPEF (Mon)] was 16 ± 50 (SD) in patients with Arg/Arg, and 16 ± 41(SD) in patients with Gly/Gly (P>0.05). This result suggests that the Arg16Gly genotype does not influence the preferential bronchodilator effect of Sal or Mon in mild to moderate persistent asthma patients, at least, in 16 weeks follow-up.
- © 2012 ERS