title: Predictive performance of the modification of diet in renal disease and Cockcroft-Gault equations for estimating renal function.
abstract: Recent recommendations emphasize the need to assess kidney function using creatinine-based predictive equations to optimize the care of patients with chronic kidney disease. The most widely used equations are the Cockcroft-Gault (CG) and the simplified Modification of Diet in Renal Disease (MDRD) formulas. However, they still need to be validated in large samples of subjects, including large non-U.S. cohorts. Renal clearance of (51)Cr-EDTA was compared with GFR estimated using either the CG equation or the MDRD formula in a cohort of 2095 adult Europeans (863 female and 1232 male; median age, 53.2 yr; median measured GFR, 59.8 ml/min per 1.73 m(2)). When the entire study population was considered, the CG and MDRD equations showed very limited bias. They overestimated measured GFR by 1.94 ml/min per 1.73 m(2) and underestimated it by 0.99 ml/min per 1.73 m(2), respectively. However, analysis of subgroups defined by age, gender, body mass index, and GFR level showed that the biases of the two formulas could be much larger in selected populations. Furthermore, analysis of the SD of the mean difference between estimated and measured GFR showed that both formulas lacked precision; the CG formula was less precise than the MDRD one in most cases. In the whole study population, the SD was 15.1 and 13.5 ml/min per 1.73 m(2) for the CG and MDRD formulas, respectively. Finally, 29.2 and 32.4% of subjects were misclassified when the CG and MDRD formulas were used to categorize subjects according to the Kidney Disease Outcomes Quality Initiative chronic kidney disease classification, respectively.
authors.affiliation: Department of Physiology and Biophysics, Georges Pompidou European Hospital, 20 rue Leblanc, 75015 Paris, France. marc.froissart@egp.aphp.fr
authors.forename: Marc
authors.initials: M
authors.lastname: Froissart
authors.forename: Jerome
authors.initials: J
authors.lastname: Rossert
authors.forename: Christian
authors.initials: C
authors.lastname: Jacquot
authors.forename: Michel
authors.initials: M
authors.lastname: Paillard
authors.forename: Pascal
authors.initials: P
authors.lastname: Houillier
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015982:Bias; D015992:Body Mass Index; D001835:Body Weight; D002860:Chromium Radioisotopes; D003404:Creatinine / Q000097:blood; D004492:Edetic Acid; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007676:Kidney Failure, Chronic / Q000175:diagnosis / Q000178:diet therapy* / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D011237:Predictive Value of Tests; D012737:Sex Factors
chemical_list: D002860:Chromium Radioisotopes; D004492:Edetic Acid; D003404:Creatinine