Grotz W H, Mundinger F A, Gugel B, Exner V M, Kirste G, Schollmeyer P J
Department of Medicine, Albert-Ludwigs-University of Freiburg, Germany.
Transplantation. 1995 Apr 15;59(7):982-6.
Kidney transplant recipients are exposed to multiple factors that lead to osteoporosis after kidney transplantation. Recent short-term longitudinal studies revealed a strong decline of bone mineral density (BMD) within 1 year after transplantation. The long-term course of BMD after transplantation is still unknown. Therefore, we performed a cross-sectional study to determine BMD in 190 renal graft recipients (mean age 44 years, range 20-71 years) by dual-energy x-ray absorptiometry at various time intervals up to 20 years after transplantation (range 0-237 months). Mean BMD of graft recipients was lower than BMD values of an age- and sex-matched European reference collective at every time of measurement after renal transplantation (P < 0.01). Lowest mean BMD values were measured 12-24 months after transplantation. No loss of BMD occurred after the second posttransplant year beyond the normal age- and sex-dependent decline of BMD. Mean daily prednisone dosage was significantly higher within the first 2 posttransplant years compared with the later posttransplant period (13.1 +/- 6.2 vs. 6.7 +/- 3.4 mg/day). Other drugs or metabolic causes, including daily dosage of CsA, AZA, parathormone level, and graft function, did not show additional important differences before and after the second posttransplant year. Interpreting the results of a cross-sectional study in light of a time-dependent process, we suggest that the preexisting low BMD of kidney transplant recipients at the time of transplantation is further strongly reduced within the initial 2 posttransplant years, probably due mainly to the effect of prednisone therapy. After that time, when prednisone dosage is below a threshold of 7.5 mg/day, only a moderate, normal loss of BMD is apparent, even in patients up to 20 years after transplantation.
肾移植受者会接触到多种导致肾移植后骨质疏松的因素。近期的短期纵向研究显示，移植后1年内骨矿物质密度（BMD）急剧下降。移植后BMD的长期变化过程仍不清楚。因此，我们进行了一项横断面研究，通过双能X线吸收法在移植后长达20年（0 - 237个月）的不同时间间隔测定190例肾移植受者（平均年龄44岁，范围20 - 71岁）的BMD。肾移植后每次测量时，移植受者的平均BMD均低于年龄和性别匹配的欧洲参考人群的BMD值（P < 0.01）。移植后12 - 24个月时测得的平均BMD值最低。移植后第二年之后，除了正常的年龄和性别相关的BMD下降外，未出现BMD丢失。与移植后期相比，移植后前两年的平均每日泼尼松剂量显著更高（13.1 ± 6.2 vs. 6.7 ± 3.4 mg/天）。其他药物或代谢因素，包括环孢素A（CsA）、硫唑嘌呤（AZA）的每日剂量、甲状旁腺激素水平和移植肾功能，在移植后第二年前后未显示出其他重要差异。鉴于这是一个随时间变化的过程来解释横断面研究的结果，我们认为肾移植受者在移植时预先存在的低BMD在移植后的最初两年内会进一步大幅降低，这可能主要是由于泼尼松治疗的影响。在那之后，当泼尼松剂量低于7.5 mg/天的阈值时，即使在移植后长达20年的患者中，也仅出现中度的、正常的BMD丢失。
