肾小球滤过率评估公式的适用性分析

Applicability of Cockcroft-Gault and MDRD equations to estimate the glomerular filtration rates

目的:以99mTc-DTPA同位素测定的肾小球滤过率(glomerular filtration rate,GFR)为参考标准,评估美国肾脏病基金会推荐的Cockcroft-Gault(C-G)公式与简化MDRD公式对肾功能进行分期的适用性。方法:以143例慢性肾脏病患者为研究对象,采用肾动态显像99mTc标记法测定GFR,根据慢性肾脏病的分期标准,将患者分成4组:A组30例,GFR≥90 ml/min;B组36例,60 ml/min≤GFR<90 ml/min;C组47例,30 ml/min≤GFR<60 ml/min;D组30例GFR<30 ml/min。对各组患者分别采用CG公式、简化MDRD公式估算GFR值并用体表面积(BSA)标准化,分别与不同组BSA标准化的99mTc-DTPA测得GFR进行比较,并进行相关性分析,评价估算公式的准确性。结果:(1)采用肾动态显像99mTc标记法测定的GFR与CG公式估算出的4组GFR值[单位:ml.min-1.(1.73m2)-1]之间的相关系数为rA=-0.166(P>0.05);rB=0.742(P<0.01);rC=0.625(P<0.01);rD=-0.186(P>0.05)。(2)采用肾动态显像99mTc标记法测定出的GFR与简化MDRD公式估算的4组GFR值[单位:ml.min-1.(1.73m2)-1]之间相关系数:rA=0.024(P>0.05);rB=0.674(P<0.01);rC=0.714(P<0.01);rD=-0.155(P>0.05)。结论:CG公式、简化MDRD公式更适用于我国汉族慢性肾脏病2期、3期患者;相比之下,CG公式的准确性略优于MDRD公式,对于我国汉族人群肾功能的估算公式,需要进一步研究。

Objective： To investigate the application of Cockcroft-Gault（C-G） and simplified MDRD equations in estimating the glomerular filtration rates（GFR） in different stage renal disease.Methods： A total of 143 cases with primary or secondary chronic kidney disease were enrolled in this study.GFR by 99mTc-DTPA clearance rate was used as the reference standard.The patients were divided into four subgroups according to the GFR obtained from Gates.Group A,30 cases,GFR≥90 ml/min;group B,36 cases,60 ml/min≤GFRGFR90 ml/min;group C,47 cases,30 ml/min≤GFR60 ml/min;group D,30 cases,GFR30 ml/min.Serum creatinine and body weight were used to estimate GFR（eGFR） by C-G equation and simplified MDRD equation respectively.To evaluating the accuracy of Cockcroft-Gault and simplified MDRD equations,eGFRs were compared with measured GFR.Pearson relation coefficients were used to describe the association between the measured GFR and to GFR obtained from C-G equations or MDRD equations.Results： The GFR[ml·min-1·（1.73m2）-1] obtained from Gates methods and C-G equations ：the correlation coefficients of four subgroups were as follows： rA=-0.166（P0.05）,rB=0.742（P0.01）,rC=0.625（P0.01）,rD=-0.186（P0.05）.The GFR[ml·min-1·（1.73m2）-1] obtained from Gates methods and MDRD equations： the correlation coefficients of four subgroups were as follows： rA=0.024（P0.05）,rB=0.674（P0.01）,rC=0.714（P0.01）,rD=-0.155（P0.05）.Conclusion： Cockcroft-Gault（C-G） and simplified MDRD equations were more suitable for patients with chronic kidney disease in 2,3 stage,by contrast,accuracy of CG formula was slightly better than the MDRD formula in Han nationality.Further research is needed for renal function estimation formulas in Chinese Han population.