title: Epidemiology of acute kidney injury in Canadian critical care units: a prospective cohort study.
abstract: OBJECTIVE
  We undertook this study to characterize the epidemiology of acute kidney injury (AKI) in Canadian critical care units. We aimed to identify predictors of mortality for patients diagnosed with AKI.
  
  
  METHODS
  We conducted a prospective cohort study of consecutive patients admitted to critical care units at five Canadian hospitals over a 30-day period. Each patient was followed until hospital discharge or for a maximum of 30 days. The serum creatinine criteria for the Acute Kidney Injury Network (AKIN-SCr) system were used to identify, classify, and characterize patients who developed AKI. We used multivariable logistic regression to predict 30-day mortality among patients with AKI.
  
  
  RESULTS
  We identified 603 patients, 161 (26.7%) of whom developed AKI. Compared to patients without AKI, those with AKI were more likely to die (29.2% vs 8.6%, P < 0.001). The risk of death increased with increasing AKIN-SCr stage (P < 0.001). In all, 19 patients (11.8% of those with AKI) commenced dialysis a median of one day (interquartile range, one to two days) after AKI diagnosis. At AKI diagnosis, the blood urea nitrogen (BUN) level (adjusted odds ratio [OR] 1.68, 95% confidence interval [CI] 1.01 to 2.79/10 mmol·L(-1)) and serum bicarbonate (adjusted OR 0.88, 95% CI 0.81 to 0.95/1 mmol·L(-1)) were associated with 30-day mortality and predicted death with an area under the receiver-operating characteristic curve of 0.79 (95% CI 0.71 to 0.86).
  
  
  CONCLUSIONS
  Acute kidney injury is a common complication of critical illness in Canada. The development of even the mildest stage of AKI is associated with a substantially higher risk of death. At AKI diagnosis, routine clinical data may be helpful for predicting adverse outcomes.
authors: Division of Nephrology, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.
authors: Ayodele
authors: A
authors: Odutayo
authors: Neill K J
authors: NK
authors: Adhikari
authors: James
authors: J
authors: Barton
authors: Karen E A
authors: KE
authors: Burns
authors: Jan O
authors: JO
authors: Friedrich
authors: David
authors: D
authors: Klein
authors: Stephen
authors: S
authors: Lapinsky
authors: Sasha
authors: S
authors: Litwin
authors: Aleksander
authors: A
authors: Meret
authors: Rahim
authors: R
authors: Moineddin
authors: Bonnie
authors: B
authors: Richardson
authors: Robert
authors: R
authors: Richardson
authors: Alina
authors: A
authors: Zaltzman
authors: Michelle
authors: M
authors: Hladunewich
authors: Ron
authors: R
authors: Wald
mesh_terms: D058186:Acute Kidney Injury / Q000453:epidemiology* / Q000401:mortality / Q000628:therapy; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002170:Canada / Q000453:epidemiology; D015331:Cohort Studies; D003404:Creatinine / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D006761:Hospitals / Q000706:statistics & numerical data; D006801:Humans; D007362:Intensive Care Units; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011446:Prospective Studies; D012372:ROC Curve; D006435:Renal Dialysis / Q000379:methods*; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D003404:Creatinine