title: Trends in acute kidney injury, associated use of dialysis, and mortality after cardiac surgery, 1999 to 2008.
abstract: BACKGROUND
  The development of acute kidney injury (AKI) after cardiac surgery is associated with significant mortality, morbidity, and cost. The last decade has seen major changes in the complexity of cardiac surgical candidates and in the number and type of cardiac surgical procedures being performed.
  
  
  METHODS
  Using data from the Nationwide Inpatient Sample, we determined the annual rates of AKI, AKI requiring dialysis (AKI-D), and inpatient mortality after cardiac surgery in the United States in the years 1999 through 2008.
  
  
  RESULTS
  Inpatient mortality with AKI and AKI-D decreased from 27.9% and 45.9%, respectively, in 1999 to 12.8% and 35.3%, respectively, in 2008. Compared with 1999, the odds of AKI and AKI-D in 2008, adjusted for demographic and clinical factors, were 3.30 (95% confidence interval [CI]: 2.89 to 3.77) and 2.23 (95% CI: 1.78 to 2.80), respectively. Corresponding adjusted odds of death associated with AKI and AKI-D were 0.31 (95% CI: 0.26 to 0.36) and 0.47 (95% CI: 0.34 to 0.65.) Taken together, the attributable risks for death after cardiac surgery associated with AKI and AKI-D increased from 30% and 5%, respectively, in 1999 to 47% and 14%, respectively, in 2008.
  
  
  CONCLUSIONS
  In sum, despite improvements in individual patient outcomes over the decade 1999 to 2008, the population contribution of AKI and AKI-D to inpatient mortality after surgery increased over the same period.
authors.affiliation: Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Palo Alto, California, USA. colinlenihan@gmail.com
authors.forename: Colin R
authors.initials: CR
authors.lastname: Lenihan
authors.forename: Maria E
authors.initials: ME
authors.lastname: Montez-Rath
authors.forename: Christina T
authors.initials: CT
authors.lastname: Mora Mangano
authors.forename: Glenn M
authors.initials: GM
authors.lastname: Chertow
authors.forename: Wolfgang C
authors.initials: WC
authors.lastname: Winkelmayer
mesh_terms: D058186:Acute Kidney Injury / Q000453:epidemiology* / Q000209:etiology; D000368:Aged; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D016001:Confidence Intervals; D005260:Female; D005500:Follow-Up Studies; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D008297:Male; D008875:Middle Aged; D009017:Morbidity / Q000639:trends; D006435:Renal Dialysis / Q000009:adverse effects*; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D014481:United States / Q000453:epidemiology