title: Long-term outcomes in online hemodiafiltration and high-flux hemodialysis: a comparative analysis.
abstract: OBJECTIVE
  Theoretical advantages exist of online hemodiafiltration (HDF) over high-flux hemodialysis (HD), but outcome data are scarce. Our objective was to compare outcomes between these modalities.
  
  
  METHODS
  We studied 858 incident patients in our incremental high-flux HD and online HDF program during an 18-yr period. We compared outcomes, including survival, in those who were treated predominantly with HDF (>50% sessions) and those with high-flux HD. Survival comparisons used a Cox model taking into account the time-varying proportion of time spent on HDF. All data were prospectively collected.
  
  
  RESULTS
  A total of 152,043 sessions were delivered as HDF and 291,222 as high-flux HD. A total of 232 (27%) patients were treated predominantly with HDF and 626 (73%) with high-flux HD. Total Kt/V, serum albumin, erythropoietin resistance index, and BP were similar in both groups up to 5 yr after HD initiation. Intradialytic hypotension was less frequent in the predominant HDF group. Predominant HDF treatment was associated with a reduced risk for death after correction for confounding variables. In a second Cox model, proportion of time spent on HDF predicted survival, such that patients who were treated solely by HDF would have a hazard for death of 0.66 compared with those who solely used high-flux HD.
  
  
  CONCLUSIONS
  We found no benefits of HDF over high-flux HD with respect to anemia management, nutrition, mineral metabolism, and BP control. The mortality benefit associated with HDF requires confirmation in large randomized, controlled trials. These data may contribute to their design.
authors.affiliation: Department of Renal Medicine, Lister Hospital, Corey's Mill Lane, Stevenage, UK. evilar@doctors.org.uk
authors.forename: Enric
authors.initials: E
authors.lastname: Vilar
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Fry
authors.forename: David
authors.initials: D
authors.lastname: Wellsted
authors.forename: James E
authors.initials: JE
authors.lastname: Tattersall
authors.forename: Roger N
authors.initials: RN
authors.lastname: Greenwood
authors.forename: Ken
authors.initials: K
authors.lastname: Farrington
mesh_terms: D000328:Adult; D000368:Aged; D000740:Anemia / Q000188:drug therapy; D002118:Calcium / Q000097:blood; D004921:Erythropoietin / Q000627:therapeutic use; D005260:Female; D017583:Hemodiafiltration / Q000009:adverse effects / Q000379:methods* / Q000401:mortality*; D006801:Humans; D053208:Kaplan-Meier Estimate; D007676:Kidney Failure, Chronic / Q000401:mortality* / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D015596:Nutrition Assessment; D010281:Parathyroid Hormone / Q000097:blood; D010710:Phosphates / Q000097:blood; D016016:Proportional Hazards Models; D006435:Renal Dialysis / Q000009:adverse effects / Q000379:methods* / Q000401:mortality*; D012189:Retrospective Studies; D012709:Serum Albumin / Q000378:metabolism; D016896:Treatment Outcome; D014882:Water-Electrolyte Balance
chemical_list: D010281:Parathyroid Hormone; D010710:Phosphates; D012709:Serum Albumin; D004921:Erythropoietin; D002118:Calcium