Chen Nan, Shi Hao, Zhang Luxia, Zuo Li, Xie Jingyuan, Xie Danshu, Karger Amy B, Miao Shiyuan, Ren Hong, Zhang Wen, Wang Weiming, Pan Yujing, Minji Wei, Sui Zhun, Okparavero Aghogho, Simon Andrew, Chaudhari Juhi, Eckfeldt John H, Inker Lesley A, Levey Andrew S
Department of Nephrology, Institute of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Renal Division, Department of Medicine, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, China.
Kidney Med. 2020 Jan 31;2(2):172-180. doi: 10.1016/j.xkme.2019.11.004. eCollection 2020 Mar-Apr.
RATIONALE & OBJECTIVES: Estimated glomerular filtration rate (eGFR) using creatinine and cystatin C (eGFR) may be less accurate compared to measured GFR (mGFR) in China than in North America, Europe, and Australia due to variation across regions in their non-GFR determinants. The non-GFR determinants of β-microglobulin (B2M) and β-trace protein (BTP) differ from those of creatinine and cystatin C. Thus, the average eGFR using all 4 markers (eGFR) could be more accurate than eGFR in China.
Diagnostic test study.
SETTING & PARTICIPANTS: 1,066 participants in Shanghai and Beijing with creatinine and cystatin C and 666 participants with all 4 filtration markers.
Index tests were previously developed equations for eGFR using creatinine, cystatin C, B2M, and BTP and combinations. The reference test was mGFR using plasma clearance of iohexol. We compared the performance of eGFR to eGFR using the proportion of participants with errors in eGFR >30% of mGFR (1 - P) and root mean square error (RMSE) of the regression of eGFR on mGFR on the logarithmic scale. We also compared classification and reclassification of mGFR categories using eGFR compared to eGFR.
Accuracy was significantly better for eGFR (1 - P of 10.4% and RMSE of 0.214) compared to eGFR (1 - P of 13.8% and RMSE of 0.232; = 0.004 and = 0.006, respectively). However, improvements in accuracy did not generally translate into significant improvement in classification or reclassification of mGFR categories.
Study population may not be generalizable to clinical settings other than large urban medical centers in China.
A panel of endogenous filtration markers including B2M and BTP in addition to creatinine and cystatin C may improve GFR estimation in China. Further study is necessary to determine whether GFR estimation using B2M and BTP can be improved and whether these improvements lead to useful clinical applications.
由于中国与北美、欧洲和澳大利亚在非肾小球滤过率（GFR）决定因素方面存在差异，在中国，使用肌酐和胱抑素C估算的肾小球滤过率（eGFR）可能比测量的GFR（mGFR）准确性更低。β-微球蛋白（B2M）和β-微量蛋白（BTP）的非GFR决定因素与肌酐和胱抑素C不同。因此，使用所有4种标志物估算的平均eGFR（eGFR）在中国可能比eGFR更准确。
诊断试验研究。
上海和北京的1066名有肌酐和胱抑素C检测结果的参与者，以及666名有所有4种滤过标志物检测结果的参与者。
指标检测是先前开发的使用肌酐、胱抑素C、B2M和BTP及组合来估算eGFR的方程。参考检测是使用碘海醇血浆清除率测定的mGFR。我们通过比较eGFR>mGFR的30%（1 - P）的参与者比例以及eGFR与mGFR对数尺度回归的均方根误差（RMSE），来比较eGFR与eGFR的性能。我们还比较了使用eGFR与eGFR对mGFR类别进行的分类和重新分类。
与eGFR相比，eGFR的准确性显著更高（1 - P为10.4%，RMSE为0.214），而eGFR的1 - P为13.8%，RMSE为0.232；P分别为0.004和0.006）。然而，准确性的提高通常并未转化为mGFR类别分类或重新分类的显著改善。
研究人群可能无法推广至中国大型城市医疗中心以外的临床环境。
除肌酐和胱抑素C外，包括B2M和BTP在内的一组内源性滤过标志物可能会改善中国的GFR估算。有必要进一步研究以确定使用B2M和BTP估算GFR是否可以得到改善，以及这些改善是否能带来有用的临床应用。
