Effects of three immunosuppressive regimens on vertebral bone density in renal transplant recipients: a prospective study

Abstract

The influence of three different immunosuppressive regimens with cyclosporine (CsA) on the development of osteopenia in renal transplant patients was assessed. Fifty-three adults with first kidney transplants participated in a randomized trial to analyze the efficacy of three different immunosuppressive regimens: CsA alone (group 1), CsA plus steroids (group 2), and CsA plus steroids plus azathioprine (group 3). Lumbar spine bone mineral density was assessed by dual energy x-ray absorptiometry every 6 months for 18 months. The values for trabecular mass were expressed as bone mineral density and as a fraction of the standard deviation of the mean of the normal value for patient's sex and decade of age (Z-score). Statistical analysis was performed on Z-score and "Z-score change" (value after 6 months minus the basal value at transplantation). At the 18th month, the Z-score increased significantly in treatment group 1 without steroids (P=0.006) and decreased significantly in steroid-treated groups 2 (P<0.001) and 3 (P<0.001). Comparing the two genders, Z-score decreased less in premenopausal women than in men (P=0.018). "Z-score change" did not correlate with steroid dosage, was high in patients with high basal bone mineral density, and was directly associated with the duration of dialysis (P=0.008). In conclusion, premenopausal transplant recipients showed a lower decrease of lumbar bone mineral density than men. In transplant recipients given CsA with steroids, lumbar bone mineral density decreased significantly, while it increased significantly in patients given CsA alone.