Bronchoprotection with a leukotriene receptor antagonist in asthmatic preschool children.

We hypothesized that a leukotriene receptor antagonist (LTRA) could provide bronchoprotection against the cold, dry air-induced response in asthmatic preschool children. In a randomized, double-blind, placebo-controlled crossover study, we examined the effect of the specific LTRA montelukast at 5 mg/d for 2 d on the bronchoconstriction induced by hyperventilation of cold, dry air in 13 asthmatic children 3 to 5 yr old. The bronchoconstriction was measured as the specific airway resistance (sRaw) in a whole-body plethysmograph before and 4 min after challenge with cold, dry air. The repeatability of the bronchoprotection was examined by repeating the placebo-controlled study in six of the 13 children. sRaw increased by an average of 46% (95% confidence interval [CI]: 30 to 63%) after placebo treatment and 17% (95% CI: 3 to 31%) after montelukast (p < 0.01). Eight of the children were receiving regular treatment with budesonide delivered by an inhaler with a spacer in a mean daily dose of 350 microg, but the bronchoprotection provided by montelukast was independent of concurrent steroid treatment. There was no convincing evidence of failure to respond, and the protective effect of montelukast was consistent upon repeated testing (p = 0. 02). We conclude that the LTRA montelukast provided clinically significant bronchoprotection against the effect of hyperventilation of cold dry air in asthmatic children 3 to 5 yr old. The bronchoprotection appeared to be homogeneous among the children, and seemed independent of steroid treatment. This suggests that LTRAs may be of therapeutic use in limiting clinical symptoms of asthma in young children.