常用肾功能指标对老年人肾小球滤过率判断的应用价值

Application value of common renal function markers for judging glomerular filtration rate in aged people

目的了解常用肾功能指标判断肾小球滤过率(GFR)的价值。方法老年患者105例,分为肾病组、非肾病1组(年龄<80岁)、非肾病2组(年龄≥80岁),测血清尿素氮(BUN)、血清肌酐(SCr)、血清半胱氨酸蛋白酶抑制剂C(Cys-C),计算MDRD方程,各指标作相关分析与回归分析,组内异常率比较。结果非肾病组BUN、SCr异常率(18.57%、12.86%)与Cys-C异常率(1.43%)比较,差异有统计学意义(P<0.001,P<0.01);肾病组BUN、SCr异常率(60.00%、65.71%)与Cys-C异常率(54.29%)比较,差异无统计学意义(P>0.05)。全部患者Cys-C与年龄、简化MDRD方程(eGFRa)、中国改良MDRD方程7(C-eGFR7)、中国改良简化MDRD方程(C-eGFRa)相关,相关系数(r)分别为0.414、-0.677、-0.736、-0.677,有统计学意义(P<0.001);与改良MDRD方程7(eGFR7)r=-0.258,有统计学意义(P<0.05)。结论Cys-C特异性高于BUN、SCr,能够更准确反映老年患者GFR;C-eGFR7、C-eGFRa准确性高于eGFR7、eGFRa。

Objective To evaluate the application value of commom clinical renal function markers for judging glomerular filtration rate（GFR）in Aged People. Methods One hundred and five cases of gerontic patients in hospital were divided into one group with kidney disease and two other groups without kidney disease in different ages（age=80）. Serum creatinine（SCr）, serum urea nitrogen（BUN）, serum cystatin C （Cys-C）concentration were determined to calculate modified MDRD equations. Contrast all the items between three groups with abnormal cases and abnormal rates. Cys-C ,eGFR7 ,eGFRa ,C-eGFR7 ,C-eGFRa were analyzed by correlation and regression. Results The means of Bun,Scr were normal,and the abnormal rates of Bun,Ser were significantly higher（18.57%, 12.86%）than that of Cys-C （1.43%）in the two groups without kidney disease （P〈0.05）. While in the group with kidney disease ,the means of BUN,SCr were higher than normal,there was no difference in the abnormal rates of BUN,SCr（60.00%, 65.71%）and Cys-C（54.29%）（P〉0. 05）. The correlation coefficient of Cys C level in all patients with ages and eGFRa,C-eGFR7 ,C- eGFRa was 0.414,-0.677,-0.736,-0.677 respectively （P〈0.001）,with eGFR7 was -0.258 （P〈0.05）. The correlative coefficient between MDRD equations was 0.359,0.367,0.359 respectively （P〈0.001）. The results of linear regression equation between Cys-C and eGFRT,C-eGFRT,C-eGFRa had statistical significance except eGFRa. Conclusions Cys-C,as a GFR marker,is a more sensitive assay than BUN,SCr in aged patients,while C-eGFR7 and C-eGFR are more accurate than eGFR7,eGFRa.