Effects of montelukast on symptoms and eNO in children with mild to moderate asthma

Background: Asthma is a chronic inflammatory airway disease. Exhaled nitric oxide (eNO) is a marker reflecting airway inflammation. This study was conducted to investigate whether montelukast, a leukotriene receptor antagonist, could be used for the management of asthma and how fast the montelukast sodium decreased airway inflammation as demonstrated by eNO levels. Methods: Twenty children aged 6-14 years (mean age: 9.2 ± 2.4 years; mean weight 30 ± 4.6 kg) with mild to moderate asthma were recruited for the study. They received montelukast plus an inhaled short-acting beta2 agonist as open and uncontrolled therapy. Asthma score (AS) and peak expiratory flow rate (PEFR) and eNO concentrations were measured at pretreatment (0 week) and post-treatment (1 and 2 weeks) as well as 2 weeks after withdrawal of therapy. Results: In one week, the eNO levels (33.3 ± 15.5 p.p.b. vs 14.8 ± 8.6 p.p.b.; P < 0.05), and AS (4.2 ± 1.3 vs 1.8 ± 1.3; P < 0.05) decreased rapidly, and PEFR (206.9 ± 69.7 L/min vs 236.2 ± 69.8 L/min; P < 0.05) increased. Concurrent beta2 agonist use decreased from a mean ± SD of 2.2 ± 0.4-1.3 ± 0.3 puffs per weeks (P < 0.05). After the withdrawal of treatment for 2 weeks, the eNO levels (29.2 ± 16.1 p.p.b) rebounded again, although the improvements in AS (1.1 ± 1.3) and PEFR (245.0 ± 91.3 L/min) persisted. Conclusion: Oral montelukast sodium treatment of these children with mild to moderate asthma effectively improved asthmatic symptoms and suppressed airway inflammation in 1 week, suggesting that this leukotriene antagonist combined with short-acting beta2 agonists may provide effective treatment option in mild to moderate childhood asthma. Larger, controlled, and double-blinded studies are needed to confirm these preliminary open uncontrolled observations.