title: Association between First Nations ethnicity and progression to kidney failure by presence and severity of albuminuria.
abstract: BACKGROUND
  Despite a low prevalence of chronic kidney disease (estimated glomerular filtration rate [GFR]<60 mL/min per 1.73 m2), First Nations people have high rates of kidney failure requiring chronic dialysis or kidney transplantation. We sought to examine whether the presence and severity of albuminuria contributes to the progression of chronic kidney disease to kidney failure among First Nations people.
  
  
  METHODS
  We identified all adult residents of Alberta (age≥18 yr) for whom an outpatient serum creatinine measurement was available from May 1, 2002, to Mar. 31, 2008. We determined albuminuria using urine dipsticks and categorized results as normal (i.e., no albuminuria), mild, heavy or unmeasured. Our primary outcome was progression to kidney failure (defined as the need for chronic dialysis or kidney transplantation, or a sustained doubling of serum creatinine levels). We calculated rates of progression to kidney failure by First Nations status, by estimated GFR and by albuminuria category. We determined the relative hazard of progression to kidney failure for First Nations compared with non-First Nations participants by level of albuminuria and estimated GFR.
  
  
  RESULTS
  Of the 1 816 824 participants we identified, 48 669 (2.7%) were First Nations. First Nations people were less likely to have normal albuminuria compared with non-First Nations people (38.7% v. 56.4%). Rates of progression to kidney failure were consistently 2- to 3-fold higher among First Nations people than among non-First Nations people, across all levels of albuminuria and estimated GFRs. Compared with non-First Nations people, First Nations people with an estimated GFR of 15.0-29.9 mL/min per 1.73 m2 had the highest risk of progression to kidney failure, with similar hazard ratios for those with normal and heavy albuminuria.
  
  
  CONCLUSIONS
  Albuminuria confers a similar risk of progression to kidney failure for First Nations and non-First Nations people.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Samuel
authors.forename: Luz
authors.initials: L
authors.lastname: Palacios-Derflingher
authors.forename: Marcello
authors.initials: M
authors.lastname: Tonelli
authors.forename: Braden
authors.initials: B
authors.lastname: Manns
authors.forename: Lynden
authors.initials: L
authors.lastname: Crowshoe
authors.forename: Sofia B
authors.initials: SB
authors.lastname: Ahmed
authors.forename: Min
authors.initials: M
authors.lastname: Jun
authors.forename: Nathalie
authors.initials: N
authors.lastname: Saad
authors.forename: Brenda R
authors.initials: BR
authors.lastname: Hemmelgarn
mesh_terms: D000328:Adult; D000416:Alberta; D000419:Albuminuria / Q000150:complications* / Q000208:ethnology; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D007198:Indians, North American; D008297:Male; D008875:Middle Aged; D051437:Renal Insufficiency / Q000453:epidemiology* / Q000208:ethnology / Q000209:etiology*; D012307:Risk Factors