糖尿病患者肾小球滤过率评估方法的临床应用研究

目的探讨适用于2型糖尿病患者肾脏功能评估的肾小球滤过率(GFR)估算公式,比较简化肾脏病膳食改善试验(MDRD)、推荐的肾脏病膳食改善试验(rMDRD)、慢性肾脏病流行病学协作组(CKD-EPI)和半胱氨酸蛋白酶抑制剂C(Cys C)相关GFR 4个GFR估算公式的实际应用。方法收集178例2型糖尿病患者的相关资料,检测血清肌酐(SCr)及Cys C浓度,同时行同位素99m锝-二乙三胺五乙酸(99mTc-DTPA)肾动态显像,得出同位素GFR(iGFR),并以此作为GFR的参考标准。依据美国糖尿病协会(ADA)标准将178例患者分成3个亚组GFR 15～59、60～89、≥90 mL/(min·1.73 m2)],对各公式的GFR估算值(eGFR)与iGFR进行配对t检验、相关分析、Bland-Altman分析、受试者工作特征(ROC)曲线及15%、30%、50%符合率比较。结果 MDRD公式应用于GFR<60 mL/(min·1.73 m2)的患者,其eGFR与iGFR相关性较好,符合率较高,偏差无统计学意义;应用于GFR≥60 mL/(min·1.73 m2)的患者,其eGFR与iGFR差异有统计学意义(P<0.001)。rMDRD公式计算eGFR在准确性、诊断效能等方面与MDRD公式无明显差异。CKD-EPI公式应用于GFR≥90 mL/(min·1.73 m2)的患者,其eGFR与iGFR的符合率高于MDRD和rMDRD;应用于GFR 60～89 mL/(min·1.73 m2)的患者时,其符合率低于Cys C GFR公式。Cys C GFR公式得出的eGFR与iGFR的相关性、偏差、一致性及符合率均明显优于MDRD和rMDRD公式,尤其应用于GFR≥90 mL/(min·1.73 m2)的患者时,其eGFR与iGFR偏差无统计学意义,明显优于其他3个公式。结论 4个GFR估算公式均能准确估算GFR<60 mL/(min·1.73 m2)的2型糖尿病患者的肾功能水平。在GFR≥90 mL/(min·1.73 m2)时,Cys C GFR公式明显优于传统以SCr为基础的GFR估算公式。

Clinical application of the estimation of glomerular filtration rate in diabetes mellitus patients

Objective To investigate the suitable equation of glomerular filtration rate（GFR） in estimating renal function for type 2 diabetes mellitus patients,and to compare the application effects of modification of diet in renal disease（MDRD）,reexpressed modification of diet in renal disease（rMDRD）,chronic kidney disease epidemiology collaboration（CKD-EPI） and cystatin C（Cys C）-based equations for GFR.Methods Clinical data from 178 type 2 diabetes mellitus patients were collected for the detection of serum creatinine（SCr） level,Cys C level and renal clearance of 99mTc-diethylenetriamine pentaacetic acid-deoxyglucose（99mTc-DTPA） which was used as the reference of isotopic GFR（iGFR）.According to the standard of the American Diabetes Association（ADA）,the 178 patients were classified into 3 groups.The equations for estimated GFR（eGFR） were compared with iGFR by paired t test,linear analysis,Bland and Altman procedures,receiver operating characteristic（ROC） curves and 15%,30% and 50% coincidences.Results When GFR〈60 mL/（min·1.73 m2）,there was no significant difference between eGFR and iGFR in MDRD equation,but when GFR≥60mL/（min·1.73 m2）,there was significant difference（P〈0.001）.There was no significant difference of eGFR for rMDRD equation in accuracy and diagnostic sensitivity.When GFR≥90 mL/（min·1.73 m2）,the coincidences were higher in CKD-EPI equation than those in MDRD and rMDRD equation,but when GFR 60-89 mL/（min·1.73 m2）,they were lower than those in Cys C GFR equation.The Cys C GFR equation had a better correlation with eGFR and iGFR,a less bias,a higher deviation and a higher coincidence than those in MDRD and rMDRD equations,especially when GFR≥90 mL/（min·1.73 m2）,only there was no significant difference between eGFR and iGFR,and Cys C GPR equation was better than the other 3 equations.Conclusions The 4 equations can estimate GFR accurately for type 2 diabetes mellitus patients when GFR〈60 mL/（min·1.73 m2）,but when GFR≥90 mL/（min·1.73 m2）,Cys C GFR equation shows a significant superiority than the old SCr based equations.