title: [The application of glomerular filtration rate estimation equations in different stages of chronic kidney disease].
abstract: OBJECTIVE
  To understand the applicability of MDRD equation in Chinese patients with chronic kidney disease (CKD). Glomerular filtration rate (GFR) estimated with MDRD equation, abbreviated MDRD equation and Cockcroft-Gault equation was compared with (99m)Tc-DTPA plasma clearance by dual plasma sampling method in different stages of CKD.
  
  
  METHODS
  CKD were diagnosed according to K/DOQI guideline.298 patients with CKD were selected. Patients'sex, age, height and body weight were recorded and plasma creatinine, urea nitrogen and albumin were measured in a single clinical laboratory. (99m)Tc-DTPA plasma clearance was calculated and standardized by body surface area (sGFR). GFRs estimated with MDRD equation 7, abbreviated MDRD equation and Cockcroft-Gault equation (7GFR, aGFR and cGFR) were compared with sGFR in different stages of CKD.
  
  
  RESULTS
  There were 165 male and 133 female in the selected 298 patients with CKD;the average age was (52.5 +/- 15.5) years. There was significant difference between the GFRs of the 3 equations with sGFR in different stages of CKD (P < 0.001). 7GFR, aGFR and cGFR were significantly higher than sGFR in CKD stages 5-4; the lower the sGFR, the more the differences. 7GFR, aGFR and cGFR were significantly lower than sGFR in CKD stage 2-1; the higher the sGFR, the more the differences.
  
  
  CONCLUSIONS
  Our results showed that in Chinese population with CKD, MDRD equation 7, abbreviated MDRD equation and Cockcroft-Gault equation overestimate actual GFR in CKD stages 4-5 and underestimate GFR in CKD stages 1-2. These results indicate that MDRD equation and its modifications for estimation of GFR should be amended when applying to Chinese patients with CKD in clinical practice.
authors.affiliation: Institute of Nephrology and Division of Nephrology, the First Hospital, Peking University, Beijing 100034, China.
authors.forename: Ying-chun
authors.initials: YC
authors.lastname: Ma
authors.forename: Li
authors.initials: L
authors.lastname: Zuo
authors.forename: Mei
authors.initials: M
authors.lastname: Wang
authors.forename: Yu-hong
authors.initials: YH
authors.lastname: Zhou
authors.forename: Chun-li
authors.initials: CL
authors.lastname: Zhang
authors.forename: Guo-bin
authors.initials: GB
authors.lastname: Xu
authors.forename: Hai-yan
authors.initials: HY
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D002908:Chronic Disease; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007674:Kidney Diseases / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D035501:Uncertainty