The Effects of Low-Dose Bisphosphonate Treatment on Bone Mineral Density and Bone Turnover Markers in Elderly Patients With Osteoporosis

Background: Osteoporosis is commonly treated with bisphosphonates. These drugs promote osteoclast apoptosis, which suppresses bone resorption. However, the probability of side effects increases with long-term use of bisphosphonates. There are several reports in Asia that show comparable effects between low and conventional doses of bisphosphonates; however, such reports are lacking in Korea. Here, we report a case series of 7 patients with osteoporosis — all women aged over 70 years — who were treated with bisphosphonates administered every other week. Methods: Patients who had been diagnosed with osteoporosis and treated with a less frequent dose of bisphosphonates at a tertiary university hospital from January 2010 to May 2016 were included in this study. Bone mineral density (BMD) was assessed at the baseline and at a 12-month interval after the first administration of low-dose bisphosphonates by using dual-energy X-ray absorptiometry. The bone turnover marker C-terminal telopeptide (CTX) was evaluated at 3, 6, and 12 months after the first administration. Results:After 12 months of treatment with a lower dose of bisphosphonates, BMD increased and CTX levels were suppressed. The mean change in BMD was 4.0% at the lumbar spine, 3.1% at the femur neck, and 1.5% at the total hip; CTX was suppressed by 34% at 3 months, 42% at 6 months, and 44% at the end of the treatment. Conclusion: We found that low-dose bisphosphonate therapy improved BMD and suppressed bone turnover rates in elderly Korean women.