Bone Mineral Density in Asthmatic Patients Treated with Inhaled Corticosteroids: a Case-control Study

Recent studies suggest that inhaled corticosteroids can adversely affect bone metabolism. The objective of this study was to evaluate the importance of these adverse effects in a case-control study. Bone mineral density (BMD) was measured in 48 asthmatic adults (15 males and 33 females) treated with inhaled steroids (beclomethasone or budesonide) and in 48 gender and age-matched healthy subjects at baseline and at 2 yrs. Vertebral BMD was measured by dual energy X-ray densitometry. Patients had been treated with a dose of 662 +/- 278 micrograms (range 300-1,000 micrograms) of beclomethasone dipropionate or budesonide for more than 1 yr (mean duration of treatment 10.6 yrs, range 1-16 yrs). Twenty four patients had needed 1-6 short courses of oral steroids and seven had received oral corticosteroids (mean daily dose 6.2 mg prednisone) for 2-15 yrs more than 4 yrs prior to the BMD measurements. During the follow-up, 14 patients required 1-3 short courses of oral steroids. There was no correlation either between inhaled corticosteroid doses or duration of treatment and BMD values. There were no significant differences in BMD baseline values between patients and healthy controls. BMD significantly decreased in both groups at 2 yrs, from 1.08 +/- 0.19 to 1.05 +/- 0.19 g.cm-2 (p = 0.002) in asthmatics versus 1.12 +/- 0.17 to 1.09 +/- 0.18 g.cm-2 (p = 0.008) in controls. There were no significant differences in BMD loss between patients and healthy controls. Furthermore, no differences were found in bone loss when pre- and postmenopausal women were compared with their healthy control counterparts. No differences in baseline BMD were found between patients who had received regular oral corticosteroid therapy or booster courses of oral corticosteroids and those who had not. Inhaled corticosteroid treatment at a mean dose of 662 micrograms.day-1 and sporadic booster courses of oral corticosteroids do not further increase bone mass loss with respect to that expected from natural bone mass loss.