title: Plasma Urate and Risk of a Hospital Stay with AKI: The Atherosclerosis Risk in Communities Study.
abstract: OBJECTIVE
  Higher urate levels are associated with higher risk of CKD, but the association between urate and AKI is less established. This study evaluated the risk of hospitalized AKI associated with urate concentrations in a large population-based cohort. To explore whether urate itself causes kidney injury, the study also evaluated the relationship between a genetic urate score and AKI.
  
  
  METHODS
  A total of 11,011 participants from the Atherosclerosis Risk in Communities study were followed from 1996-1998 (baseline) to 2010. The association between baseline plasma urate and risk of hospitalized AKI, adjusted for known AKI risk factors, was determined using Cox regression. Interactions of urate with gout and CKD were tested. Mendelian randomization was performed using a published genetic urate score among the participants with genetic data (n=7553).
  
  
  RESULTS
  During 12 years of follow-up, 823 participants were hospitalized with AKI. Overall, mean participant age was 63.3 years, mean eGFR was 86.3 ml/min per 1.73 m(2), and mean plasma urate was 5.6 mg/dl. In patients with plasma urate >5.0 mg/dl, there was a 16% higher risk of hospitalized AKI for each 1-mg/dl higher urate (adjusted hazard ratio, 1.16; 95% confidence interval, 1.10 to 1.23; P<0.001). When stratified by history of gout, the association between higher urate and AKI was significant only in participants without a history of gout (P for interaction=0.02). There was no interaction of CKD and urate with AKI, nor was there an association between genetic urate score and AKI.
  
  
  CONCLUSIONS
  Plasma urate >5.0 mg/dl was independently associated with risk of hospitalized AKI; however, Mendelian randomization did not provide evidence for a causal role of urate in AKI. Further research is needed to determine whether lowering plasma urate might reduce AKI risk.
authors.affiliation: Departments of Medicine and kgreenb4@jhmi.edu.
authors.forename: Keiko I
authors.initials: KI
authors.lastname: Greenberg
authors.affiliation: Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Epidemiology, Johns Hopkins School of Public Health, Baltimore, Maryland;
authors.forename: Mara A
authors.initials: MA
authors.lastname: McAdams-DeMarco
authors.affiliation: Department of Epidemiology, Johns Hopkins School of Public Health, Baltimore, Maryland; Renal Division, University Medical Center Freiburg, Freiburg, Germany; and.
authors.forename: Anna
authors.initials: A
authors.lastname: Köttgen
authors.affiliation: Departments of Medicine and Department of Epidemiology, Johns Hopkins School of Public Health, Baltimore, Maryland; Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Lawrence J
authors.initials: LJ
authors.lastname: Appel
authors.affiliation: Department of Epidemiology, Johns Hopkins School of Public Health, Baltimore, Maryland; Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Josef
authors.initials: J
authors.lastname: Coresh
authors.affiliation: Departments of Medicine and Department of Epidemiology, Johns Hopkins School of Public Health, Baltimore, Maryland; Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Morgan E
authors.initials: ME
authors.lastname: Grams
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood* / Q000453:epidemiology / Q000235:genetics; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006073:Gout / Q000097:blood / Q000453:epidemiology; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D057182:Mendelian Randomization Analysis; D008875:Middle Aged; D011446:Prospective Studies; D051436:Renal Insufficiency, Chronic / Q000097:blood / Q000453:epidemiology; D012307:Risk Factors; D014481:United States / Q000453:epidemiology; D014527:Uric Acid / Q000097:blood*
chemical_list: D014527:Uric Acid
keywords: acute renal failure; clinical epidemiology; risk factors