title: Predicting hospital mortality in critically ill cancer patients according to acute kidney injury severity.
abstract: BACKGROUND
  Acute kidney injury (AKI) is a frequent complication in hospitalized patients, especially in those in intensive care units (ICU). The RIFLE classification might be a valid prognostic factor for critically ill cancer patients. The present study aims to evaluate the discriminatory capacity of RIFLE versus other general prognostic scores in predicting hospital mortality in critically ill cancer patients.
  
  
  METHODS
  This is a single-center study conducted in a cancer-specialized ICU in Brazil. All of the 288 patients hospitalized from May 2006 to June 2008 were included. RIFLE classification, APACHE II, SOFA, and SAPS II scores were calculated and the area under receiver operating characteristic (AROC) curves and logistic multiple regression were performed using hospital mortality as the outcome.
  
  
  RESULTS
  AKI, defined by RIFLE criteria, was observed in 156 (54.2%) patients. The distribution of patients with any degree of AKI was: risk, n = 96 (33.3%); injury, n = 30 (10.4%), and failure, n = 30 (10.4%). Mortality was 13.6% for non-AKI patients, 49% for RIFLE 'R' patients, 62.3% for RIFLE 'I' patients, and 86.8% for RIFLE 'F' patients (p = 0.0006). Logistic regression analysis showed that RIFLE criteria, APACHE II, SOFA, and SAPS II were independent factors for mortality in this population. The discrimination of RIFLE was good (AROC 0.801, 95% CI 0.748-0.854) but inferior compared to those of APACHE II (AROC 0.940, 95% CI 0.915-0.966), SOFA (AROC 0.910, 95% CI 0.876-0.943), and SAPS II (AROC 0.869, 95% CI 0.827-0.912).
  
  
  CONCLUSIONS
  AKI is a frequent complication in ICU patients with cancer. RIFLE was inferior to commonly used prognostic scores for predicting mortality in this cohort of patients.
authors.affiliation: Department of Internal Medicine, School of Medicine, University of Fortaleza, Fortaleza, Brazil. alexandreliborio@yahoo.com.br
authors.forename: Alexandre Braga
authors.initials: AB
authors.lastname: Libório
authors.forename: Krasnalhia Lívia S
authors.initials: KL
authors.lastname: Abreu
authors.forename: Geraldo B
authors.initials: GB
authors.lastname: Silva
authors.forename: Rafael S A
authors.initials: RS
authors.lastname: Lima
authors.forename: Adller G C
authors.initials: AG
authors.lastname: Barreto
authors.forename: Orivaldo A
authors.initials: OA
authors.lastname: Barbosa
authors.forename: Elizabeth F
authors.initials: EF
authors.lastname: Daher
mesh_terms: D058186:Acute Kidney Injury / Q000150:complications / Q000401:mortality*; D000328:Adult; D000368:Aged; D016638:Critical Illness; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications*; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012372:ROC Curve; D012307:Risk Factors; D012720:Severity of Illness Index