title: Three-year outcomes after acute kidney injury: results of a prospective parallel group cohort study.
abstract: Using a prospective study design, we aimed to characterise the effect of acute kidney injury (AKI) on long-term changes in renal function in a general hospital population.
  
  
  
  Hospitalised patients with AKI (exposed) and hospitalised patients without AKI (non-exposed), recruited at 3 months after hospital admission.
  
  
  
  Prospective, matched parallel group cohort study, in which renal function and proteinuria were measured at 3 months, 1 year and 3 years.
  
  
  
  Single UK centre.
  
  
  
  Clinical end points at 3 years were comparison of the following variables between exposed and non-exposed groups: renal function, prevalence of proteinuria and albuminuria and chronic kidney disease (CKD) progression/development at each time point. CKD progression was defined as a decrease in the estimated glomerular filtration rate (eGFR) of ≥25% associated with a decline in eGFR stage.
  
  
  
  300 exposed and non-exposed patients were successfully matched 1:1 for age and baseline renal function; 70% of the exposed group had AKI stage 1. During follow-up, the AKI group had lower eGFR than non-exposed patients at each time point. At 3 years, the mean eGFR was 60.7±21 mL/min/1.73 m2in the AKI group compared with 68.4±21 mL/min/1.73 m2in the non-exposed group, p=0.003. CKD development or progression at 3 years occurred in 30 (24.6%) of the AKI group compared with 10 (7.5%) of the non-exposed group, p<0.001. Albuminuria was more common in the AKI group, and increased with AKI severity. Factors independently associated with CKD development/progression after AKI were non-recovery at 90 days, male gender, diabetes and recurrent AKI.
  
  
  
  AKI is associated with deterioration in renal function to 3 years, even in an unselected population with predominantly AKI stage 1. Non-recovery from AKI is an important factor determining long-term outcome.
authors.affiliation: Department of Renal Medicine, Derby Teaching Hospitals NHS Foundation Trust, Derby, UK.
authors.forename: Kerry L
authors.initials: KL
authors.lastname: Horne
authors.affiliation: Department of Renal Medicine, Derby Teaching Hospitals NHS Foundation Trust, Derby, UK.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Packington
authors.affiliation: Department of Chemical Pathology, Derby Teaching Hospitals NHS Foundation Trust, Derby, UK.
authors.forename: John
authors.initials: J
authors.lastname: Monaghan
authors.affiliation: Department of Informatics, Derby Teaching Hospitals NHS Foundation Trust, Derby, UK.
authors.forename: Timothy
authors.initials: T
authors.lastname: Reilly
authors.affiliation: Department of Renal Medicine, Derby Teaching Hospitals NHS Foundation Trust, Derby, UK.|Centre for Kidney Research and Innovation, School of Medicine, University of Nottingham, Nottingham, UK.
authors.forename: Nicholas M
authors.identifier: 0000-0003-0351-8326
authors.initials: NM
authors.lastname: Selby
mesh_terms: D058186:Acute Kidney Injury / Q000503:physiopathology*; D000368:Aged; D000419:Albuminuria / Q000209:etiology / Q000503:physiopathology; D018450:Disease Progression; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011446:Prospective Studies; D011507:Proteinuria / Q000209:etiology / Q000503:physiopathology; D051436:Renal Insufficiency, Chronic / Q000503:physiopathology; D012307:Risk Factors; D016896:Treatment Outcome
keywords: AKI; Acute Kidney Injury; Albuminuria; CKD; Chronic Kidney Disease; E-alerts