title: The association between dialysis modality and the risk for dialysis technique and non-dialysis technique-related infections.
abstract: BACKGROUND
  Infections are a major cause of morbidity and mortality among dialysis patients. Dialysis modality has been hypothesized to be a potential immunomodulatory factor. The objective of this study was to determine the influence of the first dialysis modality on the risk for infections on dialysis.
  
  
  METHODS
  Our study was conducted utilizing the Netherlands Cooperative Study on the Adequacy of Dialysis (NECOSAD) cohort of incident dialysis patients. Medical records of all patients from two tertiary care university hospitals and three regional hospitals were reviewed using pre-specified criteria. Information about infections was collected from the start of dialysis until death, modality switch, study withdrawal, kidney transplantation or at the end of the study. Age-standardized incidence rates for infections were calculated. Poisson regression analysis was used to calculate adjusted incidence rate ratios (IRRs).
  
  
  RESULTS
  In total, 452 patients, of whom 285 started with haemodialysis (HD) and 167 with peritoneal dialysis (PD), were included. The median follow-up time on the first dialysis modality was similar for HD and PD, 1.8 and 2.0 dialysis years, respectively. During the first 6 months, the age-standardized infection incidence rate was higher on HD compared with PD patients (P = 0.02). Overall, PD patients had a higher infection risk [adjusted IRR: 1.65, 95% confidence interval (CI): 1.34-2.03], which could be attributed to a 4-fold increased risk for dialysis technique-related infections. The risk for non-dialysis technique-related infections was lower in PD patients (adjusted IRR: 0.56, 95% CI: 0.40-0.79).
  
  
  CONCLUSIONS
  Overall, PD patients carry a higher risk for infections. Interestingly, the risk for non-dialysis technique-related infections was higher in HD patients. The links between dialysis modality and the immune system are expected to explain this difference, but future studies are needed to test these assumptions.
authors.affiliation: Division of Nephrology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Anouk T N
authors.initials: AT
authors.lastname: van Diepen
authors.affiliation: Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Tiny
authors.initials: T
authors.lastname: Hoekstra
authors.affiliation: Department of Nephrology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Joris I
authors.initials: JI
authors.lastname: Rotmans
authors.affiliation: Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Mark G J
authors.initials: MG
authors.lastname: de Boer
authors.affiliation: Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, The Netherlands Department of Medical Statistics and Bioinformatics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Saskia
authors.initials: S
authors.lastname: le Cessie
authors.affiliation: Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Marit M
authors.initials: MM
authors.lastname: Suttorp
authors.affiliation: Division of Nephrology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands Dianet, Amsterdam-Utrecht, The Netherlands.
authors.forename: Dirk G
authors.initials: DG
authors.lastname: Struijk
authors.affiliation: Hans Mak Institute, Naarden, The Netherlands.
authors.forename: Els W
authors.initials: EW
authors.lastname: Boeschoten
authors.affiliation: Division of Nephrology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Raymond T
authors.initials: RT
authors.lastname: Krediet
authors.affiliation: Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Friedo W
authors.initials: FW
authors.lastname: Dekker
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005440:Fluid Therapy; D005500:Follow-Up Studies; D006801:Humans; D007239:Infections / Q000453:epidemiology* / Q000209:etiology; D007676:Kidney Failure, Chronic / Q000628:therapy*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D009017:Morbidity / Q000639:trends; D009426:Netherlands / Q000453:epidemiology; D011446:Prospective Studies; D006435:Renal Dialysis; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D055815:Young Adult
keywords: epidemiology; haemodialysis; immunology; infection; peritoneal dialysis