title: Modality of chronic renal replacement therapy and survival--a complete cohort from Finland, 2000-2009.
abstract: BACKGROUND
  Studies on dialysis modality and survival have shown conflicting results, mostly due to insufficient and varying control of confounding factors. Using comprehensive data on a well-defined patient cohort, we therefore investigated the association of dialysis modality with survival on chronic renal replacement therapy (RRT) and whether this association varies between subgroups of patients.
  
  
  METHODS
  Survival analyses included all adult patients entering chronic RRT in Finland between 2000 and 2009 and used information obtained from the Finnish Registry for Kidney Diseases and the Finnish Kidney Transplant Registry. In our primary intention-to-treat (ITT) analysis, we calculated relative risk of death according to dialysis modality on Day 91 from RRT start, comparing peritoneal dialysis (PD) to haemodialysis (HD). Relative risks were adjusted for putative confounders. Interactions between treatment groups and other variables were estimated.
  
  
  RESULTS
  Of the total 4463 patients, 42% died during the 10 years of follow-up. Median survival time was 5.2 years. In unadjusted ITT analysis, relative risk of death of PD patients was 0.65 (95% CI 0.58-0.73, P < 0.001) compared with HD patients. With adjustment for 26 variables, the corresponding relative risk of death was 1.07 (95% CI 0.94-1.22, P = 0.33). When censoring at time of kidney transplantation, the result was similar with a relative risk of death of 1.09 (95% CI 0.95-1.25, P = 0.24) on PD compared with HD.
  
  
  CONCLUSIONS
  PD is associated with several factors generally related to good prognosis. After comprehensive adjustment for putative confounding factors with the ITT analysis approach, we found no significant difference in survival between PD and HD patients.
authors.affiliation: Division of Nephrology, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Mikko
authors.initials: M
authors.lastname: Haapio
authors.forename: Jaakko
authors.initials: J
authors.lastname: Helve
authors.forename: Lauri
authors.initials: L
authors.lastname: Kyllönen
authors.forename: Carola
authors.initials: C
authors.lastname: Grönhagen-Riska
authors.forename: Patrik
authors.initials: P
authors.lastname: Finne
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D005260:Female; D005387:Finland; D005500:Follow-Up Studies; D006801:Humans; D007676:Kidney Failure, Chronic / Q000401:mortality / Q000628:therapy*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D010530:Peritoneal Dialysis / Q000401:mortality*; D012042:Registries; D006435:Renal Dialysis / Q000401:mortality*; D017582:Renal Replacement Therapy / Q000401:mortality; D015996:Survival Rate; D013997:Time Factors; D044465:White People
keywords: dialysis modality; haemodialysis; peritoneal dialysis; renal replacement therapy; survival