A comparison of the bronchodilatory effect of 50 and 100 mu g salbutamol via Turbuhaler (R) and 100 mu g salbutamol via pressurized metered dose inhaler in children with stable asthma

Aim: The aim of the study was to compare the efficacy of single doses of sa lbutamol Turbuhaler(R) (50 and 100 mu g), salbutamol pressurized metered do se inhaler (pMDI) (100 mu g) and placebo in children with stable chronic re versible airway obstruction. Primary efficacy variable (FEV1-av) was calcul ated as the area under the curve of forced expiratory volume in one second (FEV1) (AUC, 0-4 h) and divided by the observed time. Design: The study was of a randomized, single-dose, crossover and double-blind design. Seven cen tres participated. FEV, was measured pre-dose and at 15 min, 0.5, 1, 1.5, 2 , 3 and 4 h post study dose. Patients: Forty asthmatic children (9 girls) w ith a mean age of 9 years (range: 6-12), mean FEV1 of 1.61 (range: 0.9-2.3) and a mean FEV, in percentage of predicted normal value of 80% (range: 61- 109) were randomized into the study. The mean reversibility 30 min after in haling 2 x 100 mu g salbutamol from pMDI was 20% (range: 9-45) or 15% (rang e: 8-27) in percentage of predicted normal value. Results: The mean FEV1-av was 1.63 1 for placebo, 1.71 1 for 50 mu g salbutamol Turbuhaler, 1.76 1 f or 100 mu g salbutamol Turbuhaler and 1.76 for 100 mu g salbutamol pMDI. Co rresponding values for maximum FEV1 were 1.76, 1.85, 1.87 and 1.871, respec tively. There were no statistically significant differences between the act ive treatments in FEV1-av or maximum FEV1. All active treatments were signi ficantly better than placebo. Conclusion: No significant differences in bro nchodilating effect between 50, 100 mu g salbutamol Turbuhaler and 100 mu g salbutamol pMDI in children, aged 6-12 years, with stable asthma could be demonstrated. All active treatments were significantly better than placebo. (C) 1999 Elsevier Science B.V. All rights reserved.