Bone turnover during high dose inhaled corticosteroid treatment.

This study was performed to determine the effects of high doses of two inhaled corticosteroids, beclomethasone dipropionate and budesonide, on biochemical indices of bone turnover (urinary hydroxyproline:creatine and calcium:creatinine ratios, plasma alkaline phosphatase, and parathyroid hormone). Twelve healthy male doctors, aged 25-36 (mean 30) years, were studied. After a week's run in period eight subjects inhaled beclomethasone dipropionate 2000 micrograms/day and eight inhaled budesonide 1800 micrograms/day for 28 days; this was followed by a week without any treatment. During treatment with beclomethasone dipropionate there was a significant increase in the hydroxyproline:creatinine ratio (a 46% increase at 28 days), and a fall in serum alkaline phosphatase activity (a 7.4% fall at 28 days). There were no significant changes during budesonide treatment. Thus high dose inhaled beclomethasone dipropionate increased biochemical markers of bone resorption and reduced serum alkaline phosphatase, a marker of bone mineralisation. A prospective study in asthmatic patients is indicated to assess the long term effects of high dose inhaled corticosteroids on bone mass.