title: Functional status, time to transplantation, and survival benefit of kidney transplantation among wait-listed candidates.
abstract: BACKGROUND
  In the context of an aging end-stage renal disease population with multiple comorbid conditions, transplantation professionals face challenges in evaluating the global health of patients awaiting kidney transplantation. Functional status might be useful for identifying which patients will derive a survival benefit from transplantation versus dialysis.
  
  
  METHODS
  Retrospective cohort study of wait-listed patients using data for functional status from a national dialysis provider linked to United Network for Organ Sharing registry data.
  
  
  METHODS
  Adult kidney transplantation candidates added to the waiting list between 2000 and 2006.
  
  
  METHODS
  Physical Functioning scale of the Medical Outcomes Study 36-Item Short Form Health Survey, analyzed as a time-varying covariate.
  
  
  RESULTS
  Kidney transplantation; survival benefit of transplantation versus remaining wait-listed.
  
  
  METHODS
  We used multivariable Cox regression to assess the association between physical function with study outcomes. In survival benefit analyses, transplantation status was modeled as a time-varying covariate.
  
  
  RESULTS
  The cohort comprised 19,242 kidney transplantation candidates (median age, 51 years; 36% black race) receiving maintenance dialysis. Candidates in the lowest baseline Physical Functioning score quartile were more likely to be inactivated (adjusted HR vs highest quartile, 1.30; 95% CI, 1.21-1.39) and less likely to undergo transplantation (adjusted HR vs highest quartile, 0.64; 95% CI, 0.61-0.68). After transplantation, worse Physical Functioning score was associated with shorter 3-year survival (84% vs 92% for the lowest vs highest function quartiles). However, compared to dialysis, transplantation was associated with a statistically significant survival benefit by 9 months for patients in every function quartile.
  
  
  CONCLUSIONS
  Functional status is self-reported.
  
  
  CONCLUSIONS
  Even patients with low function appear to live longer with kidney transplantation versus dialysis. For wait-listed patients, global health measures such as functional status may be more useful in counseling patients about the probability of transplantation than in identifying who will derive a survival benefit from it.
authors.affiliation: Renal Electrolyte & Hypertension Division, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA; Department of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA. Electronic address: peter.reese@uphs.upenn.edu.
authors.forename: Peter P
authors.initials: PP
authors.lastname: Reese
authors.affiliation: Department of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA.
authors.forename: Justine
authors.initials: J
authors.lastname: Shults
authors.affiliation: Renal Electrolyte & Hypertension Division, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA.
authors.forename: Roy D
authors.initials: RD
authors.lastname: Bloom
authors.affiliation: Department of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA.
authors.forename: Adam
authors.initials: A
authors.lastname: Mussell
authors.affiliation: Renal Electrolyte & Hypertension Division, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA; Department of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA.
authors.forename: Meera N
authors.initials: MN
authors.lastname: Harhay
authors.affiliation: Department of Surgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA.
authors.forename: Peter
authors.initials: P
authors.lastname: Abt
authors.affiliation: Department of Surgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Levine
authors.affiliation: Division of Nephrology, University of California-San Francisco, San Francisco, CA.
authors.forename: Kirsten L
authors.initials: KL
authors.lastname: Johansen
authors.affiliation: Department of Medical Ethics and Health Policy, University of Pennsylvania, Philadelphia, PA; Division of Geriatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA.
authors.forename: Jason T
authors.initials: JT
authors.lastname: Karlawish
authors.affiliation: Renal Electrolyte & Hypertension Division, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA; Department of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA.
authors.forename: Harold I
authors.initials: HI
authors.lastname: Feldman
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D005260:Female; D006304:Health Status; D006305:Health Status Indicators; D006801:Humans; D053208:Kaplan-Meier Estimate; D007676:Kidney Failure, Chronic / Q000401:mortality / Q000601:surgery* / Q000628:therapy; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D006435:Renal Dialysis; D012189:Retrospective Studies; D015996:Survival Rate; D013997:Time Factors; D061665:Time-to-Treatment / Q000706:statistics & numerical data*; D014850:Waiting Lists
keywords: 36-Item Short Form Health Survey (SF-36); End-stage renal disease (ESRD); dialysis; functional status; kidney transplant allocation; kidney transplantation; physical function; post-transplantation complications; renal replacement therapy modality; survival benefit; transplant waiting list