title: Frailty, Length of Stay, and Mortality in Kidney Transplant Recipients: A National Registry and Prospective Cohort Study.
abstract: To test whether frailty, a novel measure of physiologic reserve, is associated with longer kidney transplant (KT) length of stay (LOS), and modifies the association between LOS and mortality.
  
  
  
  Better understanding of LOS is necessary for informed consent and discharge planning. Mortality resulting from longer LOS has important regulatory implications for hospital and transplant programs. Which recipients are at risk of prolonged LOS and its effect on mortality are unclear. Frailty is a novel preoperative predictor of poor KT outcomes including delayed graft function, early hospital readmission, immunosuppression intolerance, and mortality.
  
  
  
  We used registry-augmented hybrid methods, a novel approach to risk adjustment, to adjust for LOS risk factors from the Scientific Registry of Transplant Recipients (n = 74,859) and tested whether (1) frailty, measured immediately before KT in a novel cohort (n = 589), was associated with LOS (LOS: negative binomial regression; LOS ≥2 weeks: logistic regression) and (2) whether frailty modified the association between LOS and mortality (interaction term analysis).
  
  
  
  Frailty was independently associated with longer LOS [relative risk = 1.15, 95% confidence interval (CI): 1.03-1.29; P = 0.01] and LOS ≥2 weeks (odds ratio = 1.57, 95% CI: 1.06-2.33; P = 0.03) after accounting for registry-based risk factors, including delayed graft function. Frailty also attenuated the association between LOS and mortality (nonfrail hazard rate = 1.55 95% CI: 1.30-1.86; P < 0.001; frail hazard rate = 0.97, 95% CI: 0.79-1.19, P = 0.80; P for interaction = 0.001).
  
  
  
  Frail KT recipients are more likely to experience a longer LOS. Longer LOS among nonfrail recipients may be a marker of increased mortality risk. Frailty is a measure of physiologic reserve that may be an important clinical marker of longer surgical LOS.
authors.affiliation: *Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD †Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD ‡Division of Geriatric Medicine and Gerontology, Johns Hopkins University School of Medicine, Baltimore, MD.
authors.forename: Mara A
authors.initials: MA
authors.lastname: McAdams-DeMarco
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: King
authors.forename: Xun
authors.initials: X
authors.lastname: Luo
authors.forename: Christine
authors.initials: C
authors.lastname: Haugen
authors.forename: Sandra
authors.initials: S
authors.lastname: DiBrito
authors.forename: Ashton
authors.initials: A
authors.lastname: Shaffer
authors.forename: Lauren M
authors.initials: LM
authors.lastname: Kucirka
authors.forename: Niraj M
authors.initials: NM
authors.lastname: Desai
authors.forename: Nabil N
authors.initials: NN
authors.lastname: Dagher
authors.forename: Bonnie E
authors.initials: BE
authors.lastname: Lonze
authors.forename: Robert A
authors.initials: RA
authors.lastname: Montgomery
authors.forename: Jeremy
authors.initials: J
authors.lastname: Walston
authors.forename: Dorry L
authors.initials: DL
authors.lastname: Segev
mesh_terms: D000368:Aged; D005260:Female; D000073496:Frailty; D006801:Humans; D016030:Kidney Transplantation / Q000401:mortality*; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012042:Registries; D012307:Risk Factors