Inhaled corticosteroids have been used in the treatment of chronic obstructive pulmonary disease (COPD) for many years. However the adverse effects of corticosteroids on bone formation may require special consideration in these patients. This study was undertaken to investigate the effects of long-term inhaled beclomethasone dipropionate treatment on the biochemical markers of bone formation. For this purpose, serum osteocalcin, alkaline phosphatase, free calcium, and inorganic phosphate levels were measured in 65 male COPD patients. Patients in the control group (n = 30) had not taken oral or inhaled corticosteroids for at least 1 year. Only those patients using beclomethasone with metered-dose inhalers were included in the treatment group (n = 35). The mean age of the control group was 61.63 +/- 1.84 (mean +/- SEM). In the treatment group, the mean age was 59.10 +/- 2.29 and patients in this group had taken beclomethasone for an average time of 23.94 +/- 2.72 months (for at least 12 months) at an average concentration of 1,142.0 +/- 79.64 mug/d. The mean serum osteocalcin levels in the control group and treatment group were 7.03 +/- 0.19 ng/mL and 3.74 +/- 0.12 ng/mL, respectively. Comparison of values between groups indicates that serum osteocalcin levels in patients using beclomethasone were significantly lower than that of patients in the control group. Serum alkaline phosphatase levels were 167.96 +/- 1.49 U/L and 168.17 +/- 1.60 U/L for the control and treatment groups, respectively, There was no statistically significant difference among these values (Student's t test; P > .05). The mean values of total serum calcium and inorganic phosphate were not statistically different between the groups (P > .05). These results indicate that long-term inhaled beclomethasone treatment in COPD patients may induce significant changes in osteocalcin levels and require close monitoring for osteoporotic changes. Copyright (C) 2001 by W.B. Saunders Company.