Factors Affecting Osteoporosis Following Renal Transplantation

ABSTRACT

PURPOSE: Chronic renal failure is known to occur with many disturbances in calcium metabolism including osteoporosis, bone decalcification, osteitis fibrosa cystica, and parathyroid hyperplasia. Renal transplantation may benefit the patients with chronic renal failure by reversing these disturbances, but it can also have deleterious effects on the bone. Osteoporosis remains one of the most frequent and serious complications after renal transplantation. The aim of this retrospective study is to evaluate the factors affecting osteoporosis after renal transplantation. METHODS: Bone mineral density (BMD) was measured a median 46 months (range 1~121) after renal transplantation in 118 of 274 patients between March 1991 and May 2002. At the time of bone examination, sex, age, duration of dialysis before transplantation, posttransplantation period, cumulative doses of prednisone, number of rejection, serum levels of cyclosporine, BUN, Cr, Ca, P, alkaline phosphatase (ALP), osteocalcin, urine levels of deoxypyridinoline, and cumulative doses of prednisone were measured. RESULTS: Duration between renal transplantation and BMD measurement (Ed-confirm this addition) was longer, and cumulative doses of prednisone were higher in patients whose lumbar vertebrae BMD was osteoporotic with statistical significance (P=0.023 and P=0.011, respectively). Longer duration between renal transplantation and BMD measurement and higher cumulative doses of prednisone were also seen in patients whose femoral neck BMD was osteoporotic, but without a statistical significance (P=0.186 and P=0.184, respectively). Cyclosporine level did not correlate well with either lumbar vertebrae or femoral neck BMD (P=0.800 and P=0.474). Nor did other factors show a statistically significant correlation. CONCLUSION: Our data indicated that longer duration between renal transplantation and BMD measurement and higher cumulative doses of prednisone were the statistically significant factors affecting patients with osteoporotic BMD at the lumbar vertebrae and femoral neck. To prevent osteoporosis after renal transplantation, it is important to restrict the cumulative doses of prednisone as early as possible following renal transplantation.