Objectives: To compare the effects of addition of montelukast or salmeterol to inhaled corticosteroids (ICS) on the response to rescue beta2-agonist use after exercise-induced bronchoconstriction.
Methods: A double-blind, placebo-controlled study was performed at 16 centers in the United States. Patients with asthma (n = 122, ages 15-58) whose symptoms were uncontrolled on Low-dose inhaled fluticasone and who had a history of exercise-induced worsening of asthma were randomized to receive either montelukast (10 mg once daily), salmeterol (50microg twice daily), or placebo for 4 weeks. Standardized spirometry after exercise challenge and beta2-agonist rescue was performed at baseline, week 1 and 4.
Results: Maximum achievable forced expiratory volume in 1 s (FEV1) percent predicted after rescue beta2-agonist improved in the montelukast (+1.5%) and placebo (+1.2%) groups at 4 weeks, but diminished in the salmeterol (-3.9%) group (P < 0.001). Although pre-exercise FEV1 was greatest with salmeterol (P = 0.10), patients taking montelukast had significantly greater protection from an exercise-induced decrease in FEV1 than those taking salmeterol (P < 0.001). Both the magnitude and rate of rescue bronchodilation were greater with montelukast compared with salmeterol (P < 0.001). Five minutes after rescue beta2-agonist, 92% of patients taking montelukast and 68% of those taking placebo had recovered to pre-exercise levels, whereas only 50% of those taking salmeterol had recovered to pre-exercise levels.
Conclusion: In patients whose asthma symptoms remain uncontrolled using ICS, addition of montelukast permits a greater and more rapid rescue bronchodilation with a short-acting beta2-agonist than addition of salmeterol and provides consistent and clinically meaningful protection against exercise-induced bronchoconstriction.