Further significant effects of eldecalcitol on bone resorption markers and bone mineral density in postmenopausal osteoporosis patients having undergone long-term bisphosphonate treatment

We investigated whether eldecalcitol has further significant effects on bone metabolic markers and bone mineral density (BMD) in osteoporosis patients having undergone long-term bisphosphonate treatment. Eldecalcitol treatment was initiated in 48 postmenopausal osteoporosis patients who had undergone bisphosphonate treatment with or without alfacalcidol treatment for more than 2 years (average period 6.3 years). Age, height, weight, total muscle volume, total fat volume, estimated glomerular filtration rate, and BMD at the lumbar spine, total hip, and distal third of the radius were measured as background data for each patient. Serum alkaline phosphatase, tartrate-resistant acid phosphatase 5b, calcium, and phosphate levels were measured at the baseline and 3 and 12 months after the initiation of eldecalcitol treatment, and BMD was measured at the baseline and 12 months after the initiation of eldecalcitol treatment. Tartrate-resistant acid phosphatase 5b level was significantly decreased at 3 and 12 months after the initiation of eldecalcitol treatment in comparison with the baseline level. There were no significant changes in alkaline phosphatase, calcium, or phosphate levels in comparison with the baseline levels. In addition, the lumbar spine BMD at 12 months after the initiation of treatment was significantly increased in comparison with the baseline level, although no significant changes in BMD at the total hip and distal third of the radius were observed. Eldecalcitol demonstrated significant effects in additionally decreasing the level of the bone resorption marker tartrate-resistant acid phosphatase 5b and increasing BMD at the lumbar spine, even in osteoporosis patients having undergone long-term bisphosphonate treatment.