Effects of long-term treatment with an inhaled corticosteroid on growth and pulmonary function in asthmatic children

Abstract

In a controlled prospective study we have measured growth and pulmonary function in children with asthma during long-term treatment with inhaled budesonide and compared these findings with those obtained from children not treated with corticosteroids. Two hundred and sixteen children were followed at 6 monthly intervals for 1–2 years without inhaled budesonide and then for 3–6 years on inhaled budesonide. Sixty-two children treated with theophylline, β 2-agonists and sodiumcromoglycate but not with inhaled steroids were also followed for 3–7 years (controls). During the period of budesonide therapy the mean daily dose decreased from 710 to 430 μg ( P<0·01) and no signs of tachyphylaxis to the treatment were seen. Budesonide treatment was associated with a significant reduction in the number of annual hospital admissions due to acute severe asthma (from 0·03 to 0·004 per child, P<0·001). In patients not treated with budesonide an annual decrease in % predicted FEV 1 of 1–3% was seen. In contrast FEV 1 improved significantly with time during budesonide treatment, both compared with the run-in period and with the control group ( P<0·01). Furthermore, there was a significant ( P=0·01) relationship between the duration of asthma at the start of budesonide and the annual increase in FEV 1 during budesonide therapy. After 3 years of treatment with budesonide, children who started this therapy later than 5 years after the onset of asthma had significantly lower FEV 1 (96%) than the children who received budesonide within the first 2 years after the onset of asthma (101%) ( P<0·05). No statistically significant changes in growth velocity (run-in=5·6 cm year −1, controls=5·6 cm year −1, budesonide=5·5 cm year −1) or weight gain (run-in=3·5 kg year −1, controls=3·6 kg year −1, budesonide=3·6 kg year −1) were seen during budesonide treatment. We conclude that inhaled budesonide in doses up to 400 μg per day does not stunt growth in children with asthma and that early intervention with this treatment may prevent the development of irreversible airway obstruction and reduce the risk of under-treatment. Finally, continuous long-term treatment is not associated with the development of tachyphylaxis.