Introduction: The effect of montelukast therapy on bronchial hyperreactivity (BHR) as measured by the methacholine challenge test in preschool children has not yet been reported.
Objective: To determine the effect of montelukast (4 mg/d) on BHR as evaluated by a provocative concentration of a substance causing a 20% fall in FEV1 (PC20) values in preschool asthmatic children.
Patients: A total of 26 preschool children (8 girls) aged 3.3 to 6.0 years (mean [± SD] age, 4.7 ± 0.8 years) with mild asthma.
Design: Double-blind randomized, placebo controlled, crossover study. Each child received 4 weeks of treatment with 4 mg of either montelukast or placebo separated by a 2-week washout period. Primary outcomes were PC20 values and the stage number (triple dose) at which FEV1 values dropped by 20%. Post-montelukast therapy PC20 was compared to those for the post-placebo period.
Results: Following 4 weeks of montelukast treatment, the mean PC20 was 4.79 ± 4.69 mg/mL, while after 4 weeks of placebo the mean PC20 was 2.07 ± 2.37 mg/mL (p = 0.001). The montelukast/placebo ratio for PC20 was 2.56 with a 95% confidence interval (CI) of 1.71 to 3.99. The median difference in stage was one triple dose with a 95% CI of 0.5 to 1.5.
Conclusions: Four weeks of treatment with montelukast resulted in a decreased BHR compared with placebo.