Salmeterol in paediatric asthma

Background-The addition of long acting inhaled beta(2) agonists is recommended at step 3 of the British guidelines on asthma management but a recent study suggested no additional benefit in children with asthma. Methods-The aim of this study was to compare, in a double blind, three way, crossover study, the effects of the addition of salmeterol 50 mu g bd, salmeterol 100 mu g bd, and salbutamol 200 mu g qds in asthmatic children who were symptomatic despite treatment with inhaled corticosteroids in a dose of at least 400 mu g/day over a one month period. Symptom scores, morning and evening peak expiratory flow (PEF) rates, use of rescue medication, spirometric indices, and histamine challenge were measured. Results-Forty five children aged 5-14 years were enrolled. All three treatments improved asthma control, morning and evening PEF rates, and spirometric indices with no change in bronchial hyperreactivity. A lean morning PEF was significantly better during the salmeterol treatment periods than with salbutamol treatment (p<0.05). The analysis of mean morning PEF gave an estimated treatment difference of 9.6 l/min for salmeterol 50 mu g bd versus salbutamol 200 mu g qds (95% confidence interval (CI) 2.1 to 17.1), and an estimated treatment difference of 13.8 l/min for salmeterol 100 mu g bd versus salbutamol 200 mu g qds (95% CI 6.0 to 21.5). There were no significant differences between the two doses of salmeterol and all treatments were well tolerated. Conclusions-In this population of moderate to severe asthmatic children on inhaled corticosteroids, salmeterol in a dose of either 50 mu g bd or 100 mu g bd is significantly more effective at increasing the morning PEF rate over a one month period than salbutamol 200 mu g qds. The data provided no significant evidence of a difference in efficacy between the two doses of salmeterol, 50 mu g and 100 mu g. A trial of salmeterol 100 mu g bd may be worth considering in those still symptomatic on the lower dose.