Risk factors for osteoporosis in young renal transplant recipients

Osteoporosis is a frequent complication after renal transplantation. Although several risk factors have been defined in its pathogenesis, the parameters influencing this complication in young patients with functioning grafts have not been well defined. We sought to determine the possible risk factors for osteoporosis among 55 male and 27 female renal transplant patients of mean age 35.5 +/- 11.7 years with 68.8% recipients of living-related grafts. Bone mineral densitometry was performed in all patients at 1 year after transplantation. The study utilized the World Health Organization recommendations that define normal (group 1, n = 19), osteopenic (group 2, n = 24), or osteoporotic (group 3, n = 39) patients according to T-score values. Pre- and posttransplant data included gender, age at dialysis onset; age at transplantation; pretransplant dialysis duration; body mass index (BMI); serum calcium, albumin, phosphorus, parathyroid hormone (PTH), and C-reactive protein levels; lipid profile, cumulative doses of immunosuppressive drugs, and pulse steroid dose. Differences between groups 1 and 3 showed that patients with osteoporosis were younger (P < .003) and had started dialysis and underwent transplantation at a younger age than those without osteoporosis (P < .01, P < .003). In addition, pretransplant body weight (P < .02), posttransplant BMI (P < .01), and pretransplant PTH (P < .04), posttransplant total cholesterol, and high-density lipoprotein cholesterol levels were lower among group 3 (P < .004, P < .003). Young adults who started dialysis and underwent transplantation at a younger age were prone to osteoporosis. Additionally, high BMI and cholesterol levels seemed to be preventative for bone loss after transplantation.