title: Assessing glomerular filtration rate in patients with severe heart failure: comparison between creatinine-based formulas.
abstract: OBJECTIVE
  Severe heart failure is highly associated with chronic kidney disease (CKD). Serum creatinine is a poor indicator of renal function and glomerular filtration rate (GFR) estimation is an accessible method for assessing renal function. The most popular formulas for GFR estimation are the Cockcroft-Gault (CG), the four-variable Simplified Modification of Diet in Renal Disease (sMDRD) and the recently introduced CKD-Epidemiology Collaboration (CKD-EPI). The objective of the study was to analyze the correlation between these three equations for estimating GFR in patients with severe heart failure.
  
  
  METHODS
  Cross-sectional observational study at a university reference center.
  
  
  METHODS
  GFR was estimated in patients with severe heart failure who were awaiting heart transplantation, using the CG, sMDRD and CKD-EPI formulas. These estimates were analyzed using Pearson's correlation and Bland-Altman analysis.
  
  
  RESULTS
  This study included 157 patients, of whom 32 (20.3%) were female. Normal serum creatinine concentration was observed in 21.6%. The mean GFR according to CG, sMDRD and CKD-EPI was 70.1 ± 29.5, 70.7 ± 37.5 and 73.7 ± 30.1 ml/min/1.73 m²; P > 0.05. Pearson's coefficient demonstrated good correlations between all the formulas, as did Bland-Altman. However, the patients presented GFR < 60 ml/min more frequently with the sMDRD formula (54.1% versus 40.2% for CG and 43.2% for CKD-EPI; P = 0.02).
  
  
  CONCLUSIONS
  Despite the good correlation and agreement between the three methods, the sMDRD formula classified more patients as presenting GFR less than 60 ml/min.
authors.affiliation: Postgraduate Program on Public Health, Universidade de Fortaleza, Fortaleza, Ceará, Brazil. alexandreliborio@yahoo.com.br
authors.forename: Alexandre
authors.initials: A
authors.lastname: Libório
authors.forename: Russian
authors.initials: R
authors.lastname: Uchoa
authors.forename: João
authors.initials: J
authors.lastname: Neto
authors.forename: Juan
authors.initials: J
authors.lastname: Valdivia
authors.forename: Elizabeth De Francesco
authors.initials: Ede F
authors.lastname: Daher
authors.forename: Juan
authors.initials: J
authors.lastname: Mejia
mesh_terms: D000328:Adult; D003404:Creatinine / Q000097:blood*; D003430:Cross-Sectional Studies; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006333:Heart Failure / Q000097:blood* / Q000503:physiopathology; D006801:Humans; D007668:Kidney / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D051436:Renal Insufficiency, Chronic / Q000097:blood* / Q000503:physiopathology; D015203:Reproducibility of Results; D012737:Sex Factors
chemical_list: D003404:Creatinine