Effect of Alendronate on Early Bone Loss of Renal Transplant Recipients

Abstract

Introduction. Renal transplant recipients (RTRs) are at risk of developing osteoporosis and osteopenia due to underlying renal osteodystrophy, hypophosphatemia, and immunosuppression. This process occurs more frequently in the first year after renal transplantation (RTX), resulting in eventual bone loss and fractures. The purpose of this study was to evaluate the effect of low-dose alendronate to prevent early bone loss after RTX. Patients and Methods. We prospectively studied 43 successful RTR including 22 men and 21-women with a mean overall age of 39.16 +/- 11.73 years, mean body mass index of 23.6 +/- 3.73, and mean dialysis duration of 25.73 +/- 17.67 months. We matched them based on age and sex: the alendronate-treated group received vitamin D (Vit D) during the study plus 30 mg alendronate weekly from 1 month after RTX. The control group only received Vit D. We measured serum calcium, phosphate, alkaline phosphatase, blood urea, creatinine, and intact parathyroid hormone (iPTH) at the pretransplant baseline and monthly thereafter as well as BMD of the lumbar spine, femur, and radius pretransplant baseline versus 3 and 6 months after RTX. Results. At 6 month after RTX, the lumbar BMD in the alendronate group increased significantly from 0.819 +/- 0.11 to 0.863 +/- 0.14 (P < .01), while it decreased in the control group from 0.897 +/- 0.17 to 0.817 +/- 0.16 (P < .001). There was also a significant increase in radius BMD (P < .001) and a nonsignificant increase in femoral BMD in the alendronate versus a significant decrease of femoral and radius BMD (P < .001) in the control group at 6 months. Upon multivariate analysis, there was a significant correlation between alendronate and spine BMD (r = .45, P < .001) but no linear regression between age, sex, BMI, dialysis duration of or iPTH with femoral, spine, or radius BMD changes at month 6. Conclusion. Low-dose alendronate was significantly useful to mitigate fast bone loss and increase BMD immediately after RTX.