Short-term lower leg growth in asthmatic children treated with inhaled β 2 -agonists.

Background : Knemometry studies of growth suppressive effects of inhaled glucocorticoids in children with asthma usually allow participating children to use concomitant inhaled β 2 -agonists. Systemic β 2 -agonists, however, have been found to suppress growth hormone secretion and this has caused concern about a possible confounding effect of inhaled β 2 -agonists on results of growth studies of exogenous glucocorticoids. Aim : The study evaluated whether inhaled salbutamol adversely affects short-term growth. Subjects and methods : Fifteen children aged 6–12 years with mild asthma were enrolled in a single-blind, randomized crossover study with two 2-week treatment periods and a 1-week run-in. During the active period treatment dry powder salbutamol (Ventoline Diskhaler®) 200  µg was inhaled three times a day. During the comparative period no treatment was given. Knemometry of the right lower leg was performed on the first and the last day of each period. Results : Mean lower leg growth rates (SEM) during no-treatment and salbutamol periods were 0.35 (0.06) and 0.42 (0.07)  mm per week, respectively ( P   =  0.35, t   =  -0.98, 95% CI: 0.25–0.93  mm per week). Conclusions : Inhaled salbutamol 200  µg three times daily does not suppress short-term growth in asthmatic children. Inhaled β 2 -agonists in equipotent doses and regimens can be safely used in short-term knemometric growth studies of exogenous glucocorticoids without any risk of confounding the results. [ABSTRACT FROM AUTHOR]