title: Progression of Kidney Disease in Indigenous Australians: The eGFR Follow-up Study.
abstract: Indigenous Australians experience a heavy burden of CKD. To address this burden, the eGFR Follow-Up Study recruited and followed an Indigenous Australian cohort from regions of Australia with the greatest ESRD burden. We sought to better understand factors contributing to the progression of kidney disease. Specific objectives were to assess rates of progression of eGFR in Indigenous Australians with and without CKD and identify factors associated with a decline in eGFR.
  
  
  
  This observational longitudinal study of Indigenous Australian adults was conducted in >20 sites. The baseline cohort was recruited from community and primary care clinic sites across five strata of health, diabetes status, and kidney function. Participants were then invited to follow up at 2-4 years; if unavailable, vital status, progression to RRT, and serum creatinine were obtained from medical records. Primary outcomes were annual eGFR change and combined renal outcome (first of ≥30% eGFR decline with follow-up eGFR<60 ml/min per 1.73 m(2), progression to RRT, or renal death).
  
  
  
  Participants (n=550) were followed for a median of 3.0 years. Baseline and follow-up eGFR (geometric mean [95% confidence interval], 83.9 (80.7 to 87.3) and 70.1 (65.9 to 74.5) ml/min per 1.73 m(2), respectively. Overall mean annual eGFR change was -3.1 (-3.6 to -2.5) ml/min per 1.73 m(2). Stratified by baseline eGFR (≥90, 60-89, <60 ml/min per 1.73 m(2)), annual eGFR changes were -3.0 (-3.6 to -2.4), -1.9 (-3.3 to -0.5), and -5.0 (-6.5 to -3.6) ml/min per 1.73 m(2). Across baseline eGFR categories, annual eGFR decline was greatest among adults with baseline albumin-to-creatinine ratio (ACR) >265 mg/g (30 mg/mmol). Baseline determinants of the combined renal outcome (experienced by 66 participants) were higher urine ACR, diabetes, lower measured GFR, and higher C-reactive protein.
  
  
  
  The observed eGFR decline was three times higher than described in nonindigenous populations. ACR was confirmed as a powerful predictor for eGFR decline across diverse geographic regions.
authors.affiliation: Due to the number of contributing authors, the affiliations are provided in the Supplemental Material .
authors.forename: Louise J
authors.initials: LJ
authors.lastname: Maple-Brown
authors.forename: Jaquelyne T
authors.initials: JT
authors.lastname: Hughes
authors.forename: Rebecca
authors.initials: R
authors.lastname: Ritte
authors.forename: Federica
authors.initials: F
authors.lastname: Barzi
authors.forename: Wendy E
authors.initials: WE
authors.lastname: Hoy
authors.forename: Paul D
authors.initials: PD
authors.lastname: Lawton
authors.forename: Graham R D
authors.initials: GRD
authors.lastname: Jones
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Death
authors.forename: Alison
authors.initials: A
authors.lastname: Simmonds
authors.forename: Ashim K
authors.initials: AK
authors.lastname: Sinha
authors.forename: Sajiv
authors.initials: S
authors.lastname: Cherian
authors.forename: Mark A B
authors.initials: MAB
authors.lastname: Thomas
authors.forename: Robyn
authors.initials: R
authors.lastname: McDermott
authors.forename: Alex D H
authors.initials: ADH
authors.lastname: Brown
authors.forename: Kerin
authors.initials: K
authors.lastname: O'Dea
authors.forename: George
authors.initials: G
authors.lastname: Jerums
authors.forename: Alan
authors.initials: A
authors.lastname: Cass
authors.forename: Richard J
authors.initials: RJ
authors.lastname: MacIsaac
mesh_terms: D000328:Adult; D000368:Aged; D000419:Albuminuria / Q000652:urine; D001315:Australia / Q000453:epidemiology; D003404:Creatinine / Q000652:urine; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D051436:Renal Insufficiency, Chronic / Q000208:ethnology* / Q000503:physiopathology* / Q000628:therapy; D055815:Young Adult
chemical_list: D003404:Creatinine
keywords: Australia; albuminuria; chronic kidney disease; eGFR; end stage kidney disease; humans; indigenous Australian; kidney failure, chronic; kidney function tests; longitudinal studies