title: A novel risk score for mortality in renal transplant recipients beyond the first posttransplant year.
abstract: BACKGROUND
  All-cause mortality is high after kidney transplantation (KT), but no prognostic index has focused on predicting mortality in KT using baseline and emergent comorbidity after KT.
  
  
  METHODS
  A total of 4928 KT recipients were used to derive a risk score predicting mortality. Patients were randomly assigned to two groups: a modeling population (n=2452), used to create a new index, and a testing population (n=2476), used to test this index. Multivariate Cox regression model coefficients of baseline (age, weight, time on dialysis, diabetes, hepatitis C, and delayed graft function) and emergent comorbidity within the first posttransplant year (diabetes, proteinuria, renal function, and immunosuppressants) were used to weigh each variable in the calculation of the score and allocated into risk quartiles.
  
  
  RESULTS
  The probability of death at 3 years, estimated by baseline cumulative hazard function from the Cox model [P (death)=1-0.993592764 (exp(score/100)], increased from 0.9% in the lowest-risk quartile (score=40) to 4.7% in the highest risk-quartile (score=200). The observed incidence of death increased with increasing risk quartiles in testing population (log-rank analysis, P<0.0001). The overall C-index was 0.75 (95% confidence interval: 0.72-0.78) and 0.74 (95% confidence interval: 0.70-0.77) in both populations, respectively.
  
  
  CONCLUSIONS
  This new index is an accurate tool to identify high-risk patients for mortality after KT.
authors.affiliation: Nephrology Department, Hospital Universitario de Canarias, Tenerife, Spain. domingohernandez@gmail.com
authors.forename: Domingo
authors.initials: D
authors.lastname: Hernández
authors.forename: Ana
authors.initials: A
authors.lastname: Sánchez-Fructuoso
authors.forename: José Manuel
authors.initials: JM
authors.lastname: González-Posada
authors.forename: Manuel
authors.initials: M
authors.lastname: Arias
authors.forename: Josep María
authors.initials: JM
authors.lastname: Campistol
authors.forename: Margarita
authors.initials: M
authors.lastname: Rufino
authors.forename: José María
authors.initials: JM
authors.lastname: Morales
authors.forename: Francesc
authors.initials: F
authors.lastname: Moreso
authors.forename: Germán
authors.initials: G
authors.lastname: Pérez
authors.forename: Armando
authors.initials: A
authors.lastname: Torres
authors.forename: Daniel
authors.initials: D
authors.lastname: Serón
mesh_terms: D000328:Adult; D015331:Cohort Studies; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D016030:Kidney Transplantation / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D013030:Spain / Q000453:epidemiology; D013997:Time Factors; D055815:Young Adult