I.R.C.C.S. Istituto Ortopedico Galeazzi, Milano, Italy.
Scand J Clin Lab Invest. 2012 Apr;72(2):114-20. doi: 10.3109/00365513.2011.642305. Epub 2011 Dec 27.
Abstract In this study, creatinine-based equations to evaluate glomerular filtration rate (eGFR) were proposed to more accurately assess kidney function, and cystatin C, a parameter not dependent on muscular mass, was introduced to improve GFR calculation in professional cyclists during a long-lasting race. Nine cyclists participating in the 2011 Giro d'Italia were recruited. Blood and anthropometrical data were collected the day before (T-1) the race, on the 12th day (T 12) and on the 22nd day (T 22) of the race. Haemoglobin and haematocrit were registered. Haemodilution was observed at T 12, whilst stabilization was evident at T 22. Creatinine, cystatin C concentrations and eGFR values were not modified during the observed period; only GFR evaluated with the Cockcroft-Gault (CG) formula and expressed as ml/min/1.73 m(2) significantly decreased (p < 0.05) at T 22 in comparison with T-1, probably as a consequence of weight decrease. Cystatin C levels were in the reference range, while creatinine concentrations were lower. The lowest eGFR values were observed with CG normalized and the Modification of Diet in Renal Disease (MDRD) formulas. A good correlation was observed between the MDRD and the Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equations and between CG normalized and both CKD-EPI and MDRD formulas. The worst correlation was registered between CKD-EPI creatinine and cystatin C and all the other equations. In conclusion, adaptive mechanisms of renal function allow athletes to maintain stable creatinine, cystatin C and eGFR values during a long-lasting race. The use of GFR equations to evaluate general health status of sportsmen should be recommended with caution, considering also weight modification during competition.
摘要 在这项研究中，提出了基于肌酐的方程来评估肾小球滤过率（eGFR），以更准确地评估肾功能，并引入胱抑素 C，一种不依赖肌肉质量的参数，以改善职业自行车运动员在长时间比赛中的 GFR 计算。招募了 9 名参加 2011 年环意大利自行车赛的自行车运动员。在比赛前一天（T-1）、第 12 天（T 12）和第 22 天（T 22）收集了血液和人体测量数据。记录了血红蛋白和血细胞比容。在 T 12 时观察到血液稀释，而在 T 22 时则明显稳定。在观察期间，肌酐、胱抑素 C 浓度和 eGFR 值没有改变；只有用 Cockcroft-Gault（CG）公式评估的 GFR 值并表示为 ml/min/1.73 m(2)，在 T 22 时与 T-1 相比显著降低（p < 0.05），可能是由于体重减轻所致。胱抑素 C 水平在参考范围内，而肌酐浓度较低。CG 标准化和改良肾脏病饮食（MDRD）公式的 eGFR 值最低。MDRD 方程与慢性肾脏病-流行病学合作（CKD-EPI）方程之间以及 CG 标准化与 CKD-EPI 和 MDRD 方程之间观察到良好的相关性。CKD-EPI 肌酐和胱抑素 C 与所有其他方程之间的相关性最差。总之，肾功能的适应性机制允许运动员在长时间比赛中维持稳定的肌酐、胱抑素 C 和 eGFR 值。在评估运动员整体健康状况时，应谨慎使用 GFR 方程，同时还要考虑比赛期间的体重变化。
