The effect of raloxifene on markers of bone turnover in older women living in long-term care facilities

OBJECTIVES: To examine the effect of raloxifene on bone turnover in elderly women. DESIGN: Clinical intervention. SETTING: Long-term care facilities. PARTICIPANTS: Nineteen women completed the study, mean age 85 (range 76-99). INTERVENTION: Raloxifene 60 mg was given daily for 12 weeks. MEASUREMENTS: Markers of bone turnover were plasma C-telopeptides of type I collagen (CTx), urine cross-linked N-telopeptides of type I collagen (NTx) and serum tartrate-resistant acid phosphatase (TRAP 5b), plasma osteocalcin, and serum bone alkaline phosphatase. Other markers were serum 25-OH vitamin D, parathyroid hormone, ionized calcium, and phosphate. Markers were measured at baseline, after calcium and vitamin D had been taken for 6 weeks, after raloxifene had been taken for 12 weeks, and 6 weeks after raloxifene had been stopped. Paired sample t test was used to examine changes in markers at each time point. RESULTS: Plasma CTx decreased on average by 31%, urinary NTx by 35%, plasma osteocalcin by 25%, serum bone alkaline phosphatase by 15% (P<.01), and serum TRAP 5b by 10% (P<.05) on treatment. CONCLUSION: Raloxifene reduces bone turnover in elderly women living in long-term care facilities. The effect of raloxifene on bone turnover is comparable with that seen in younger postmenopausal women.