title: The Pattern of Longitudinal Change in Serum Creatinine and 90-Day Mortality After Major Surgery.
abstract: Calculate mortality risk that accounts for both severity and recovery of postoperative kidney dysfunction using the pattern of longitudinal change in creatinine.
  
  
  
  Although the importance of renal recovery after acute kidney injury (AKI) is increasingly recognized, the complex association that accounts for longitudinal creatinine changes and mortality is not fully described.
  
  
  
  We used routinely collected clinical information for 46,299 adult patients undergoing major surgery to develop a multivariable probabilistic model optimized for nonlinearity of serum creatinine time series that calculates the risk function for 90-day mortality. We performed a 70/30 cross validation analysis to assess the accuracy of the model.
  
  
  
  All creatinine time series exhibited nonlinear risk function in relation to 90-day mortality and their addition to other clinical factors improved the model discrimination. For any given severity of AKI, patients with complete renal recovery, as manifested by the return of the discharge creatinine to the baseline value, experienced a significant decrease in the odds of dying within 90 days of admission compared with patients with partial recovery. Yet, for any severity of AKI, even complete renal recovery did not entirely mitigate the increased odds of dying, as patients with mild AKI and complete renal recovery still had significantly increased odds for dying compared with patients without AKI [odds ratio: 1.48 (95% confidence interval: 1.30-1.68)].
  
  
  
  We demonstrate the nonlinear relationship between both severity and recovery of renal dysfunction and 90-day mortality after major surgery. We have developed an easily applicable computer algorithm that calculates this complex relationship.
authors.affiliation: Center for Applied Optimization, Industrial and Systems Engineering, University of Florida, Gainesville, FL.
authors.forename: Dmytro
authors.initials: D
authors.lastname: Korenkevych
authors.affiliation: Department of Anesthesiology, College of Medicine, University of Florida, Gainesville, FL.
authors.forename: Tezcan
authors.initials: T
authors.lastname: Ozrazgat-Baslanti
authors.affiliation: Department of Anesthesiology, College of Medicine, University of Florida, Gainesville, FL.
authors.forename: Paul
authors.initials: P
authors.lastname: Thottakkara
authors.affiliation: Department of Surgery, North Florida South Georgia Veterans Affairs Medical Center, Gainesville, FL.|Department of Health Services Research, College of Public Health, University of Florida, Gainesville, FL.
authors.forename: Charles E
authors.initials: CE
authors.lastname: Hobson
authors.affiliation: Center for Applied Optimization, Industrial and Systems Engineering, University of Florida, Gainesville, FL.
authors.forename: Panos
authors.initials: P
authors.lastname: Pardalos
authors.affiliation: Center for Applied Optimization, Industrial and Systems Engineering, University of Florida, Gainesville, FL.
authors.forename: Petar
authors.initials: P
authors.lastname: Momcilovic
authors.affiliation: Department of Anesthesiology, College of Medicine, University of Florida, Gainesville, FL.
authors.forename: Azra
authors.initials: A
authors.lastname: Bihorac
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood* / Q000401:mortality*; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D003404:Creatinine / Q000097:blood*; D005260:Female; D005431:Florida / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000097:blood* / Q000401:mortality*; D012307:Risk Factors; D012720:Severity of Illness Index; D013514:Surgical Procedures, Operative
chemical_list: D015415:Biomarkers; D003404:Creatinine