DENVER—Anti-resorptive therapy with alendronate may suppress bone turnover in long-term renal transplant survivors even when intact parathyroid hormone (iPTH) is elevated, according to Japanese researchers.
At the 31st annual meeting of the American Society for Bone and Mineral Research here, Atsushi Suzuki, MD, and colleagues at Fujita Health University in Aichi, presented new data from a study that explored the effect of one-year of treatment with oral alendronate on bone metabolism in long-term kidney transplant survivors.
It is well known that bone loss during the first year after transplantation can be highly pronounced, but bone density in long-term transplant recipients has not been well studied and is controversial.
For the current study, the researchers recruited 28 renal transplant patients (13 male and 15 female). The patients had a mean age of 53.9 years and a mean duration of hemodialysis of 103 months. The mean duration of time since renal transplantation was 14 years (range 9 to 20 years).
All patients were prescribed methylprednisolone (4.07 mg/day) with various immunosuppressive agents. Twenty-six patients received cyclosporin, 13 received mizoribine, one received tacrolimus, and four patients received mycophenolate mofetil. None of the subjects had previously received anti-resorptive medications, including bisphosphonates.
Before treatment with once-weekly oral alendronate (35 mg), the mean concentration of iPTH were 137.8 pg/mL and the mean concentration of 25-hydroxyvitamin D were 20.7 ng/mL. After 12 months of treatment with alendronate, one patient died and two stopped taking alendronate, one because of having to undergo oral surgery and the other because of respiratory disease.
Mean iPTH levels significantly increased by 30% while the patients were on alendronate. However, 25-hydroxyvitamin D remained unchanged. Additionally, alendronate reduced bone-specific alkaline phosphatase by 27.3%, serum type 1 collagen N-terminal telopeptide by 26.4%, and osteocalcin levels by 44.7%.