Effects of 3 Years of Treatment with a Selective Estrogen Receptor Modulator for Postmenopausal Osteoporosis on Markers of Bone Turnover and Bone Mineral Density

Aim: The aim of the present study was to assess the changes in bone mineral density and bone turnover markers in long-term SERM. Methods: The study was performed on 25 female outpatients with primary osteoporosis treated at the Osteoporosis Department of Showa University School of Medicine. All patients had been on raloxifene (60mg/day) for ≥ 3 years. The mean patient age was 67.1 years and the women were, on average, 18.4 years postmenopausal. Levels of bone turnover markers (urinary naltrexone [NTX] and bone-specific alkaline phosphatase [BAP]) and bone mineral density (BMD; front lumbar vertebrae, three proximal femur sites, and two distal radius sites) were determined before and then annually after starting raloxifene for a period of 3 years. Results: Over the 3-year treatment period, significant decreases were seen in both urinary NTX and BAP levels. Although BMD of the lumbar vertebrae and distal radius was increased over the 3 years after initiation of raloxifene treatment, the difference failed to reach statistical significance. The BMD of the femoral neck decreased, whereas that of the femoral trochanter and femoral intertrochanter area increased. Conclusions: The selective estrogen receptor modulator raloxifene is suitable for the treatment of osteoporosis in postmenopausal patients because it reduces bone turnover while maintaining adequate bone density.