title: Intermediate and Long-term Outcomes of Survivors of Acute Kidney Injury Episodes: A Large Population-Based Cohort Study.
abstract: BACKGROUND
  The long-term prognosis after acute kidney injury (AKI) is variable. It is unclear how the prognosis of AKI and its relationship to prognostic factors (baseline kidney function, AKI severity, prior AKI episodes, and recovery of kidney function) change as follow-up progresses.
  
  
  METHODS
  Observational cohort study.
  
  
  METHODS
  The Grampian Laboratory Outcomes Morbidity and Mortality Study II (GLOMMS-II) is a large regional population cohort with complete serial biochemistry and outcome data capture through data linkage. From GLOMMS-II, we followed up 17,630 patients hospitalized in 2003 through to 2013.
  
  
  METHODS
  AKI identified using KDIGO (Kidney Disease: Improving Global Outcomes) serum creatinine criteria, characterized by baseline kidney function (estimated glomerular filtration rate [eGFR] ≥ 60, 45-59, 30-44, and <30mL/min/1.73m2), AKI severity (KDIGO stage), 90-day recovery of kidney function, and prior AKI episodes.
  
  
  RESULTS
  Intermediate- (30-364 days) and long-term (1-10 years) mortality and long-term renal replacement therapy.
  
  
  METHODS
  Poisson regression in time discrete intervals. Multivariable Cox regression for those at risk in the intermediate and long term, adjusted for age, sex, baseline comorbid conditions, and acute admission circumstances.
  
  
  RESULTS
  Of 17,630 patients followed up for a median of 9.0 years, 9,251 died. Estimated incidences of hospital AKI were 8.4% and 17.6% for baseline eGFRs≥60 and <60mL/min/1.73m2, respectively. Intermediate-term (30-364 days) adjusted mortality HRs for AKI versus no AKI were 2.48 (95% CI, 2.15-2.88), 2.50 (95% CI, 2.04-3.06), 1.90 (95% CI, 1.51-2.39), and 1.63 (95% CI, 1.20-2.22) for eGFRs≥60, 45 to 59, 30 to 44, and <30mL/min/1.73m2, respectively. Among 1-year survivors, long-term HRs were attenuated: 1.44 (95% CI, 1.31-1.58), 1.25 (95% CI, 1.09-1.43), 1.21 (95% CI, 1.03-1.42), and 1.08 (95% CI, 0.85-1.36), respectively. The excess long-term hazards in AKI were lower for lower baseline eGFRs (P for interaction = 0.01).
  
  
  CONCLUSIONS
  Nonprotocolized observational data. No adjustment for albuminuria.
  
  
  CONCLUSIONS
  The prognostic importance of a discrete AKI episode lessens over time. Baseline kidney function is of greater long-term importance.
authors.affiliation: University of Aberdeen Applied Renal Research Collaboration, Aberdeen, Scotland; NHS Grampian, Aberdeen, Scotland; Farr Institute@Scotland, Aberdeen, Scotland. Electronic address: simon.sawhney@abdn.ac.uk.
authors.forename: Simon
authors.initials: S
authors.lastname: Sawhney
authors.affiliation: University of Aberdeen Applied Renal Research Collaboration, Aberdeen, Scotland; NHS Grampian, Aberdeen, Scotland; Farr Institute@Scotland, Aberdeen, Scotland.
authors.forename: Angharad
authors.initials: A
authors.lastname: Marks
authors.affiliation: NHS Grampian, Aberdeen, Scotland.
authors.forename: Nick
authors.initials: N
authors.lastname: Fluck
authors.affiliation: University of British Columbia, Vancouver, Canada.
authors.forename: Adeera
authors.initials: A
authors.lastname: Levin
authors.affiliation: University of Aberdeen Applied Renal Research Collaboration, Aberdeen, Scotland.
authors.forename: Gordon
authors.initials: G
authors.lastname: Prescott
authors.affiliation: University of Aberdeen Applied Renal Research Collaboration, Aberdeen, Scotland; NHS Grampian, Aberdeen, Scotland; Farr Institute@Scotland, Aberdeen, Scotland.
authors.forename: Corri
authors.initials: C
authors.lastname: Black
mesh_terms: D058186:Acute Kidney Injury / Q000401:mortality* / Q000628:therapy*; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D015996:Survival Rate; D017741:Survivors; D013997:Time Factors; D016896:Treatment Outcome
keywords: AKI recovery; Acute kidney injury (AKI); acute on chronic kidney disease; baseline kidney function; chronic kidney disease (CKD); epidemiology; mortality; outcomes; prognosis; survival