title: Level of renal function in patients starting dialysis: an ERA-EDTA Registry study.
abstract: BACKGROUND
  The aims of this European study were (i) to compare the level of renal function at the start of dialysis between age groups, gender, primary renal disease, comorbid conditions, treatment modality, time periods and countries, and (ii) to determine which baseline characteristics are associated with the level of renal function at the start of dialysis.
  
  
  METHODS
  Renal registries participating in the European Renal Association-European Dialysis and Transplant Association Registry provided data on serum creatinine 0-4 weeks before the start of dialysis in incident dialysis patients in 1999 and 2003. Data were available in 11 472 patients from nine renal registries. Glomerular filtration rate (GFR) was estimated by the four-variable Modification of Diet in Renal Disease equation.
  
  
  RESULTS
  The unadjusted median eGFR at the start of dialysis was 7.0 mL/min/1.73 m(2) in the 1999 data (median serum creatinine 7.5 mg/dL) and 7.7 mL/min/1.73 m(2) in the 2003 data (serum creatinine 7.0 mg/dL). Using linear regression with adjustment for the other covariates, older patients, males, patients with diabetes mellitus, hypertension/renal vascular disease (HT/RVD) as primary renal disease (vs glomerulonephritis), ischaemic heart disease or peripheral vascular disease and patients starting on peritoneal dialysis (PD) initiated dialysis at higher levels of eGFR (range Δ eGFR: 0.1-1.2 mL/min/1.73 m(2)). Using the same analyses, eGFR differed between countries (range: 6.5-8.6 mL/min/1.73 m(2)).
  
  
  CONCLUSIONS
  During 2003, patients started dialysis at somewhat higher eGFR levels than those starting during 1999. There were also international differences in eGFR. Such differences may, at least in part, be explained by differences in creatinine measurement methods between countries and time periods. Finally, older patients, males, patients with HT/RVD or comorbidity and those starting on PD had slightly higher eGFR levels than younger patients, females, those with glomerulonephritis, without comorbidity and those starting on haemodialysis. Further research is needed into other, more clinically related factors affecting the decision to start dialysis.
authors.affiliation: ERA-EDTA Registry, Department of Medical Informatics, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. v.s.stel@amc.uva.nl
authors.forename: Vianda S
authors.initials: VS
authors.lastname: Stel
authors.forename: Charles
authors.initials: C
authors.lastname: Tomson
authors.forename: David
authors.initials: D
authors.lastname: Ansell
authors.forename: Francesco G
authors.initials: FG
authors.lastname: Casino
authors.forename: Frederic
authors.initials: F
authors.lastname: Collart
authors.forename: Patrik
authors.initials: P
authors.lastname: Finne
authors.forename: George A
authors.initials: GA
authors.lastname: Ioannidis
authors.forename: Johan
authors.initials: J
authors.lastname: De Meester
authors.forename: Mario
authors.initials: M
authors.lastname: Salomone
authors.forename: Jamie P
authors.initials: JP
authors.lastname: Traynor
authors.forename: Oscar
authors.initials: O
authors.lastname: Zurriaga
authors.forename: Kitty J
authors.initials: KJ
authors.lastname: Jager
mesh_terms: D000367:Age Factors; D000368:Aged; D003404:Creatinine / Q000097:blood; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D012042:Registries; D006435:Renal Dialysis; D012727:Sex Characteristics
chemical_list: D003404:Creatinine