Effects of inhaled corticosteroid and short courses of oral corticosteroids on bone mineral density in asthmatic patients : a 4-year longitudinal study.

BACKGROUND

It is not certain whether inhaled corticosteroid (ICS) therapy reduces bone mineral density (BMD) in asthmatic patients. In addition, the potential risk of osteoporosis associated with the rescue use of short courses of oral corticosteroids (SC-OCS) is unclear.

OBJECTIVE

To evaluate the effect of inhaled beclomethasone dipropionate (BDP) and SC-OCS on BMD in asthmatic patients.

DESIGN

A 4-year longitudinal study.

METHOD

Lumbar BMD was measured twice by dual-energy x-ray absorptiometry at a mean (+/- SD) interval of 4.2 +/- 0.1 years in 35 asthmatic adults (15 men and 20 postmenopausal women; mean age at the second evaluation, 60.6 +/- 11.5 years) who had been treated with BDP and SC-OCS.

RESULTS

The average period of BDP treatment was 7.7 +/- 2.2 years (range, 4.8 to 13.0 years) at the second evaluation. During the study period, the daily dose of BDP was 765 +/- 389 microg (range, 100 to 1,730 microg), and the frequency of SC-OCS was 1.9 +/- 2.7 courses per year (range, 0.0 to 8.9 courses per year). As a whole, lumbar BMD was unchanged during the course of the study, whereas the Z score (ie, the percentage of normal value predicted from age and sex) increased significantly. Changes in BMD and Z scores in patients receiving high doses of BDP (ie, > 1,000 microg/d; n = 9) were not significantly different from those of patients receiving lower doses (ie, <or= 1,000 microg/d; n = 26). However, patients receiving frequent SC-OCS (ie, > 2.5 courses per year; n = 9) showed a significantly greater loss in BMD and Z score compared with those receiving sporadic courses (ie, <or= 2.5 courses per year; n = 26) (p = 0.002 and p = 0.035, respectively).

CONCLUSIONS

ICS therapy per se does not affect BMD, whereas frequent SC-OCS may do so.