Background: Inhalation therapy with sodium cromoglycate is recommended as the first-line prophylactic treatment for moderate asthma in children. The availability of spacer devices with face-masks has extended the applicability of metered-dose inhalers to younger children. We studied the feasibility and effects of this therapy compared with placebo in children aged 1-4 years.
Methods: 218 children aged 1-4 years with moderate asthma were recruited through 151 general practitioners between March, 1995, and March, 1996. They were randomly assigned sodium cromoglycate (10 mg three times daily) or placebo, given by inhaler with spacer device and face-mask for 5 months. Rescue medication (ipratropium plus fenoterol aerosol) was available during the baseline period of 1 month and the intervention period. Parents completed a daily symptom-score list. The primary outcome measure was the proportion of symptom-free days in months 2 to 5. Analysis was by both intention to treat and on treatment.
Findings: 167 (77%) children completed the trial. 131 (78%) of these children used at least 80% of the recommended dose. Of the 51 children who stopped prematurely, 23 had difficulties with inhaled treatment. The mean proportion of symptom-free days for both groups was greater for the treatment period than for the baseline period (95% CI for mean difference 5.1 to 17.5 cromoglycate, 11.9 to 23.3 placebo). However there were no differences between the sodium cromoglycate and placebo groups in the proportion of symptom-free days (mean 65.7 [SD 25.3] vs 64.3 [24.5]%; 95% CI for difference -8.46 to 5.70) or in any other outcome measure.
Interpretation: Our study in a general practice setting shows that inhalation therapy with a spacer device and face-mask is feasible in a majority of children below the age of 4 years. However, long-term prophylactic therapy with inhaled sodium cromoglycate is not more effective than placebo in this age-group.