Bone changes during prednisone treatment.

To evaluate changes inbone composition during treatment with corticosteroids, the bone mineral content (BMC, measured by photon absorptiometry) and the degree of bone mineralization (measured as the bone phosphorus/hydroxyproline ratio) were determined in 18 patients during prednisone treatment for haematological and connective tissue diseases. The prednisone dose ranged from 12 to 51 mg/day (mean 27). The BMC decreased significantly (mean 2.5%) during the studied 12 weeks of treatment, but the change did not correlate significantly to the prednisone dose. The degree of bone mineralization remained unchanged, indicating equal losses of mineral and of collagen in bone during prednisone treatment. The changes correspond to a rapidly developing oesteoporotic state.