title: Estimating glomerular filtration rate by serum creatinine or/and cystatin C equations: An analysis of multi-centre Chinese subjects.
abstract: OBJECTIVE
  Various equations based on serum creatinine or/and cystatin C, required further validation in a Chinese population. We compared the performance of six Chinese equations (Mascr, Peiscr, Macys, Fengcys, Mascr-cys and Fengscr-cys) with the CKD-EPI equations in multi-centre Chinese subjects and evaluated their applicability in clinical practice.
  
  
  METHODS
  A total of 1522 adult patients from four different hospitals of China were enrolled in the study. (99m) Tc-DTPA renal dynamic imaging was used as the reference GFR (rGFR), and serum creatinine and cystatin C were measured by standardized assays. An optimal score system was implemented in the study.
  
  
  RESULTS
  The average rGFR of recruited subjects was 67.30±28.89 mL/min per 1.73m(2) . All estimated GFR (eGFR) correlated well with rGFR. In accordance with Bland-Altman analysis, the Fengscr-cys equations achieved optimal overall performance (score 14 vs 0-6), with least bias (median difference, -0.57 mL/min per 1.73m(2) ; median absolute difference, 8.83 mL/min per 1.73m(2) ), best precision (17.99 mL/min per 1.73m(2) ), highest accuracy (percentage of eGFR within 15%, 30% and 50% of the rGFR (P15 , P30 and P50 ; 49.7%, 78.7% and 91.8%, respectively); root-mean-square-error (RMSE, 16.28)). The Fengcys equation, a typical cystatin C based equation, was another well-behaved formula with an impressive performance. The Ma equations performed much poorer than the CKD-EPI equations. Consistent results can be observed in the GFR- /age- and sex-specific subgroups, while none equation yielded ideal accuracy in GFR<60 mL/min per 1.73 m(2) subgroup.
  
  
  CONCLUSIONS
  The Fengscr-cys equation appeared to achieve the best performance for GFR estimation in overall Chinese adult patients. However, further research is warranted to improve the accuracy of available equations in GFR less than 60 mL/min per 1.73 m(2) individuals.
authors.affiliation: Department of Nephrology, Jiangsu Geriatric Hospital, Nanjing, Jiangsu, China.|Division of Nephrology, Department of Geriatrics, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Xiaoshuang
authors.initials: X
authors.lastname: Ye
authors.affiliation: Division of Nephrology, Department of Internal Medicine, The Third Affiliated hospital of sun Yat-sen University, Guangzhou, China.
authors.forename: Xun
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Nephrology, The Second Affiliated hospital of Wuxi Hospital, Nanjing Medical University, Wuxi, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Song
authors.affiliation: Department of Nephrology, The FAW General Hospital, The Fourth Affiliated hospital of JiLin University, Changchun, China.
authors.forename: Xiaoxuan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Division of Nephrology, Department of Geriatrics, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Bei
authors.initials: B
authors.lastname: Zhu
authors.affiliation: Division of Nephrology, Department of Geriatrics, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Wei
authors.affiliation: Division of Nephrology, Department of Geriatrics, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Pei
authors.affiliation: Division of Respiration, Department of Geriatrics, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Jianqing
authors.initials: J
authors.lastname: Wu
authors.affiliation: Division of Nephrology, Department of Internal Medicine, The Third Affiliated hospital of sun Yat-sen University, Guangzhou, China.
authors.forename: Tanqi
authors.initials: T
authors.lastname: Lou
authors.affiliation: Department of Nephrology, Jiangsu Geriatric Hospital, Nanjing, Jiangsu, China.
authors.forename: Weihong
authors.initials: W
authors.lastname: Zhao
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People; D015415:Biomarkers / Q000097:blood; D002681:China; D003404:Creatinine / Q000097:blood*; D055316:Cystatin C / Q000097:blood*; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007668:Kidney / Q000000981:diagnostic imaging / Q000503:physiopathology*; D007674:Kidney Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000208:ethnology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D011237:Predictive Value of Tests; D011866:Radioisotope Renography / Q000379:methods; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D016284:Technetium Tc 99m Pentetate; D055815:Young Adult
chemical_list: D015415:Biomarkers; C525030:CST3 protein, human; D055316:Cystatin C; D019275:Radiopharmaceuticals; D003404:Creatinine; D016284:Technetium Tc 99m Pentetate
keywords: CKD-EPI; Chinese; cystatin C; equation; glomerular filtration rate; serum creatinine