RESUMEN
BACKGROUND: Corticosteroids are often used for the treatment of glomerular diseases. We examined whether bisphosphonate or vitamin D3 has beneficial effects on bone mineral density (BMD) in patients with glomerular diseases being treated with high-dose corticosteroids, including pulse therapy. METHODS: Thirty-eight patients (19 men and 19 women, aged 42 +/- 16 years) were randomized into three groups: bisphosphonate alone (risedronate 2.5 mg/day, group R, n = 12), vitamin D3 alone (alfacalcidol 0.5 mug/day, group A, n = 15) and the combination of both agents (group R+A, n = 11). BMD at the lumbar spine was measured before and 12 months after treatment. The biochemical parameters of bone metabolism were assessed before and 3, 6 and 12 months after treatment. RESULTS: In group R+A, BMD was significantly increased (+2.0%), whereas BMD was significantly decreased in group A (-5.6%). The BMD in group R did not show a significant change. In patients treated with steroid-pulse, BMD was decreased in groups R and A. In group R+A, BMD was significantly increased (+2.1%). Serum osteocalcin and alkaline phosphatase levels, markers of bone formation, were significantly decreased in all groups. Urinary crosslinked N-telopeptide of type I collagen (NTx) levels, a marker of bone resorption, were decreased in groups R and R+A. In patients with decreased BMD, the urinary NTx levels at baseline were significantly higher than the patients with increased BMD. CONCLUSIONS: Bisphosphonate might be beneficial for the prevention of steroid-induced bone loss in patients with glomerular diseases compared with vitamin D3. The combined therapy may be more effective, especially in patients treated with high-dose corticosteroids, including pulse therapy. A high urinary NTx level before receiving corticosteroids might be a predictive marker of the loss of BMD.