Open-label trial: effect of weekly risedronate immediately after transplantation in kidney recipients

Treatment with oral risedronate to prevent bone mineral density (BMD) loss in renal transplant recipients has been shown to be effective. There is no agreement on the optimum moment of introduction or how long it should be continued. The aim was to evaluate the effectiveness of risedronate at doses of 35 mg/week in renal transplant recipients who underwent treatment immediately after transplant.

A randomized clinical trial was performed on 101 renal transplant patients. The study group (52 patients) received 35 mg risedronate weekly, vitamin D, and calcium, whereas the control group (49 patients) received only vitamin D and calcium. At baseline, 3, 6, and 12 months, basic biochemistry and mineral bone metabolic parameters were determined. Vertebra and hip fracture assessment was performed by means of x-ray and DEXA; an intention-to-treat analysis was performed.

Patients in control group showed a significant worsening of BMD (P<0.05) 12 months into the study. At all follow-up points, lumbar BMD of the study group was significantly greater (P<0.05), whereas femoral BMD of those treated with risedronate was only significant at 6-month follow-up (P<0.05). There was a trend of more vascular calcifications and fractures in the control group, but this was not statistically significant.

Weekly oral administration of risedronate immediately after renal transplantation contributes to an improved BMD, particularly in the femoral neck at 6-month follow-up, without major side effects. Long-term follow-up is needed to establish whether oral risedronate has an influence on vascular calcifications and bone fractures.