EFFECT OF BECLOMETHASONE DIPROPIONATE ON BONE-MINERAL CONTENT ASSESSED BY X-RAY DENSITOMETRY IN ASTHMATIC-CHILDREN - A LONGITUDINAL EVALUATION

There is little information on bone turnover in asthmatic children taking long-term treatment with inhaled steroids (ICS). The aim of this longitudinal study was to determine the effects of inhaled beclomethasone dipropionate (BDP) on bone mineral density (BMD), in asthmatic children treated over a period of six months. BMD and growth were studied in two age- and sex-matched groups of asthmatic children. These comprised: 14 asthmatic children (Group 1) who had taken BDP in a dosage of 300-400 mu g daily through a 145 ml spacer device for at least 6 months (mean age 9.1 yrs); and a control group of 16 age- and sex-matched asthmatic patients (Group 2) not treated with ICS (mean age 9.5 yrs). Mean duration of asthma was 5.7 yrs in Group 1 and 5.5 yrs in Group 2. Vertebral BMD (L2-L4) was measured by dual energy X-ray absorptiometry (DEXA) at the beginning (baseline) of the study and 6 months later. There were no significant differences in the baseline bone mass (mean+/-SEM) between the two groups (0.63+/-0.03 and 0.64+/-0.02 g-cm(-2) in Group 1 and 2, respectively). During the observation period, bone density increased, by 4% (95% confidence interval (95% CT) 2-6) in the control group and by 2.3% (95% CI 0.4-4.2) in the group under BDP treatment, showing no significant influence of the treatment. No difference was found in height velocity evaluated before starting BDP and after 6 months of therapy. The results of this longitudinal study suggest that the continuous use of inhaled BDP for 6 months (300-400 mu g day(-1)) does not cause bone loss, even though, in the treated group, a slightly reduced gain in bone mass was noted. Further studies are indicated to evaluate the effect of higher doses and/or longer treatment with ICS upon bones.