Toto R D, Kirk K A, Coresh J, Jones C, Appel L, Wright J, Campese V, Olutade B, Agodoa L
Department of Medicine, University of Texas Southwestern Medical Center at Dallas 75235-8856, USA.
J Am Soc Nephrol. 1997 Feb;8(2):279-87. doi: 10.1681/ASN.V82279.
Measurement of GFR is considered the standard for estimating renal function. However, standardized accurate GFR methodology is expensive and cumbersome; therefore, estimates of GFR based on serum creatinine concentration have been employed. The purpose of the study presented here was to assess the accuracy and precision of using serum creatinine measurements to estimate GFR in the screen cohort of The African-American Study of Kidney Disease and Hypertension (AASK) Pilot Study. GFR was estimated by four methods: 100/serum creatinine, Cockcroft-Gault equation, creatinine clearance from 24-h urine collection, and a new regression equation derived from the pilot study data. These methods were compared with renal clearance of 125I-iothalamate GFR (GFR1) in 193 hypertensive (diastolic blood pressure > or = 95 mm Hg) African-American screen (142 men, 51 women). A second GFR (GFR2) was performed in 98 screen who were eligible (GFR1 25-70 mL/min per 1.73 m2) for the pilot study. Accuracy was assessed by the difference of 125I-iothalamate GFR-estimated GFR (delta GFR), and precision was estimated from the combined root mean squared error (CRMSE) and the coefficient of determination (r2). The results for accuracy (+/- SD) and precision were as follows: (1) 100/Scr, delta GFR = -0.76 +/- 16.5, CRMSE = 16.5, r2 = 0.69; (2) Cockcroft-Gault, delta GFR = 9.56 +/- 14.9, CRMSE = 17.7, r2 = 0.66; 3) 24-h creatinine clearance, delta GFR = 0.79 +/- 20.7, CRMSE = 20.7, r2 = 0.49; 4) New equation delta GFR = -0.08 +/- 12.8, CRMSE 12.7, r2 = 0.75. In comparison, a second GFR (GFR2, N = 98) had delta GFR = 1.36 +/- 8.48, CRMSE 8.6, r2 = 0.75. Estimates based on 100/SCr and the new equation were the most precise. It was concluded that GFR estimated by serum creatinine is superior to outpatient 24-h urine creatinine clearance in this population. Serum creatinine values can be used to provide a reasonably accurate estimate of GFR in hypertensive African Americans.
肾小球滤过率（GFR）的测定被视为评估肾功能的标准。然而，标准化的精确GFR测定方法既昂贵又繁琐；因此，已采用基于血清肌酐浓度的GFR估算方法。本文所呈现研究的目的是评估在非裔美国人肾脏疾病与高血压研究（AASK）试点研究的筛查队列中，使用血清肌酐测量值估算GFR的准确性和精密度。通过四种方法估算GFR：100/血清肌酐、Cockcroft - Gault方程、24小时尿肌酐清除率以及根据试点研究数据推导的新回归方程。将这些方法与193名高血压（舒张压≥95 mmHg）非裔美国人筛查对象（142名男性，51名女性）的125I - 碘肽酸盐GFR（GFR1）肾清除率进行比较。对98名符合试点研究条件（GFR1为25 - 70 mL/min/1.73 m²）的筛查对象进行了第二次GFR（GFR2）测定。通过125I - 碘肽酸盐GFR估算的GFR差值（ΔGFR）评估准确性，从合并的均方根误差（CRMSE）和决定系数（r²）估算精密度。准确性（±标准差）和精密度结果如下：（1）100/Scr，ΔGFR = -0.76 ± 16.5，CRMSE = 16.5，r² = 0.69；（2）Cockcroft - Gault方程，ΔGFR = 9.56 ± 14.9，CRMSE = 17.7，r² = 0.66；（3）24小时肌酐清除率，ΔGFR = 0.79 ± 20.7，CRMSE = 20.7，r² = 0.49；（4）新方程，ΔGFR = -0.08 ± 12.8，CRMSE = 12.7，r² = 0.75。相比之下，第二次GFR（GFR2，N = 98）的ΔGFR = 1.36 ± 8.48，CRMSE = 8.6，r² = 0.75。基于100/Scr和新方程的估算最为精确。研究得出结论，在该人群中，通过血清肌酐估算的GFR优于门诊24小时尿肌酐清除率。血清肌酐值可用于为高血压非裔美国人提供合理准确的GFR估算。
