Abstract: Ｏｂｊｅｃｔｉｖｅ：To evaluate the value and significance of full age spectrum (FAS) equation in evaluation of glomerular filtration rate (GFR) in elderly patients with chronic kidney disease (CKD).
Ｍｅｔｈｏｄｏｌｏｇｙ：A total of 191 elderly patients with CKD confirmed in our hospital were selected, and the GFR was calculated and recorded as TcGFR using the 99mTcDTPA renal dynamic imaging method as the standard. Based on serum creatinine (SCr) and cystatin C (CysC) levels, three FAS equations and CKDEPI equations were used to estimate GFR, which were recorded as eGFR1, eGFR2, eGFR3 and eGFR4, respectively. The correlation between eGFR and TcGFR calculated by the four equations and the bias of the equation were compared. and the four equations were compared with TcGFR and each other according to gender, age and CKD stage, the applicability, sensitivity, specificity, accuracy of 15％ and 30％ of GFR in elderly patients with CKD were compared by the four equations.
Ｒｅｓｕｌｔｓ：eGFR and TcGFR calculated by all equations are significantly positively correlated. eGFR4 has the best correlation with TcGFR (r=0786), followed by eGFR3; The bias of eGFR2 is the smallest, followed by eGFR3; The most accurate equation is eGFR3, followed by eGFR2; The accuracy of P15 is eGFR3>eGFR2>eGFR4>eGFR1, and the accuracy of P30 is eGFR2>eGFR3>eGFR4>eGFR1; The BlandAltman scatter diagram shows that the 95％ consistency range of eGFR3 is less than eGFR4; followed by eGFR2 and eGFR1;The area under the curve (AUC) of the four equations is eGFR2>eGFR4>eGFR3>eGFR1; the AUC of eGFR2 is the largest. Stratified results showed that eGFR2 was applicable to female in CKD13 stage; In CKD45 stage eGFR1 and eGFR3 are applicable; eGFR3 is applicable when older than 70 years old; For male in CKD13 stage, eGFR2 is applicable, and eGFR4 can also be selected when olde than 70 years old; In CKD45 stage, eGFR1, eGFR3 and eGFR4 equations can be used. eGFR3 is applicable when the age is older than 70 years old.
Ｃｏｎｃｌｕｓｉｏｎ：FAS equation is better than CKDEPI equation in estimating eGFR of elderly patients in this area. The optimal schemes are different in different age groups, different genders and different stages of CKD. The appropriate equation can be selected according to the corresponding interval as an alternative estimation method without renal dynamic imaging after admission.

Key words: full age spectrum equation, chronic kidney disease, glomerular filtration rate, serum creatinine, serum ystatin C