High-dose inhaled steroids in asthmatics: moderate efficacy gain and suppression of the hypothalamic-pituitary-adrenal (HPA) axis. Research Council of the Norwegian Thoracic Society

We wanted to evaluate the improvement in efficacy when increasing the daily dose of inhaled steroids and to compare the efficacy, safety, and tolerance of 1.6 mg beclomethasone dipropionate (BDP) with that of 2.0 mg fluticasone propionate (FP). The study was a randomized, double-blind, 3 month, multicentre study. One hundred and thirty four asthmatics currently using inhaled steroids (0.4-1.6 mg BDP or budesonide (BUD)) were stratified according to pretrial daily steroid use. Within each stratum they were randomized to either 1.6 mg BDP or 2.0 mg FP. A significant increase in the primary efficacy variables, i.e. mean morning and evening peak expiratory flow (PEF) (approximately 20 l.min-1) during the treatment period, was found for both treatments. No significant differences between the drugs were revealed for these primary or any other secondary efficacy variables (use of beta 2-agonists, symptom scores, and PEF, forced vital capacity (FVC), forced expiratory volume in one second (FEV1) recorded at the clinical visits). However, significant differences between treatments occurred regarding decrease of serum cortisol and adrenocorticotropic hormone. We conclude that, although both treatments gave statistically significant increases in efficacy parameters when compared with baseline, the increases were so small that they can be regarded as being clinically unimportant. Daily doses of BDP, 1.6 mg, and FP, 2.0 mg, had comparable effects on lung function. A suppression of the hypothalamic pituitary adrenal (HPA) axis was only found with a daily dose of 2 mg FP.