title: Refining predictive models in critically ill patients with acute renal failure.
abstract: Mortality rates in acute renal failure remain extremely high, and risk-adjustment tools are needed for quality improvement initiatives and design (stratification) and analysis of clinical trials. A total of 605 patients with acute renal failure in the intensive care unit during 1989-1995 were evaluated, and demographic, historical, laboratory, and physiologic variables were linked with in-hospital death rates using multivariable logistic regression. Three hundred and fourteen (51.9%) patients died in-hospital. The following variables were significantly associated with in-hospital death: age (odds ratio [OR], 1.02 per yr), male gender (OR, 2.36), respiratory (OR, 2.62), liver (OR, 3.06), and hematologic failure (OR, 3.40), creatinine (OR, 0.71 per mg/dl), blood urea nitrogen (OR, 1.02 per mg/dl), log urine output (OR, 0.64 per log ml/d), and heart rate (OR, 1.01 per beat/min). The area under the receiver operating characteristic curve was 0.83, indicating good model discrimination. The model was superior in all performance metrics to six generic and four acute renal failure-specific predictive models. A disease-specific severity of illness equation was developed using routinely available and specific clinical variables. Cross-validation of the model and additional bedside experience will be needed before it can be effectively applied across centers, particularly in the context of clinical trials.
authors.affiliation: Division of Nephrology, University of California, San Diego Medical Center, San Diego, California 92103, USA. rmehta@ucsd.edu
authors.forename: Ravindra L
authors.initials: RL
authors.lastname: Mehta
authors.forename: Maria T
authors.initials: MT
authors.lastname: Pascual
authors.forename: Carmencita G
authors.initials: CG
authors.lastname: Gruta
authors.forename: Shunping
authors.initials: S
authors.lastname: Zhuang
authors.forename: Glenn M
authors.initials: GM
authors.lastname: Chertow
mesh_terms: D058186:Acute Kidney Injury / Q000401:mortality* / Q000503:physiopathology / Q000628:therapy; D016638:Critical Illness; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D016015:Logistic Models; D008297:Male; D015233:Models, Statistical; D011237:Predictive Value of Tests; D012372:ROC Curve; D006435:Renal Dialysis; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index