title: Effects of Race and Sex on Measured GFR: The Multi-Ethnic Study of Atherosclerosis.
abstract: BACKGROUND
  Kidney failure disproportionately affects older blacks versus whites. The reasons are unknown and may be related to lower measured glomerular filtration rate (GFR) and higher levels of albuminuria in community-based population samples.
  
  
  METHODS
  Cross-sectional analysis of a substudy of a prospective cohort.
  
  
  METHODS
  Ancillary study following Multi-Ethnic Study of Atherosclerosis (MESA) visit 5.
  
  
  METHODS
  Age, sex, and race.
  
  
  METHODS
  Measured GFR using plasma clearance of iohexol and urine albumin-creatinine ratio (ACR).
  
  
  RESULTS
  GFR was measured in 294 participants. Mean age was 71±9 (SD) years, 47% were black, 48% were women, mean GFR was 73±19mL/min/1.73m2, and median ACR was 10.0 (IQR, 5.8-20.9) mg/g. Measured GFR was on average 1.02 (95% CI, 0.79-1.24) mL/min/1.73m2lower per year older. Mean GFR indexed for body surface area was not different between blacks versus whites (mean difference, 2.94 [95% CI, -1.37 to 7.26] mL/min/1.73m2), but was lower in women than men (mean difference, -9.34 [95% CI, -13.53 to -5.15] mL/min/1.73m2); this difference persisted and remained significant after adjustment for demographics, clinical characteristics, and measures of body size. The difference between men and women, but not between blacks and whites, was substantially greater when GFR was not indexed for body surface area. ACR was higher in older versus younger participants (mean difference, 3.2% [95% CI, 1.5%-4.8%] per year), but geometric mean ratio of ACR did not differ between blacks versus whites (mean difference, 19.7%; 95% CI, -39.1% to 6.1%) or between men versus women (mean difference, -4.4%; 95% CI, -27.7% to 26.3%).
  
  
  CONCLUSIONS
  This is a study of survivors. People who agreed to participate were younger than those who refused.
  
  
  CONCLUSIONS
  In this first community-based study that included blacks and whites, no differences in measured GFR between races were found, suggesting that other factors must account for the disproportionately higher burden of kidney failure in older blacks versus whites.
authors.affiliation: Division of Nephrology, Tufts Medical Center, Boston, MA. Electronic address: linker@tuftsmedicalcenter.org.
authors.forename: Lesley A
authors.initials: LA
authors.lastname: Inker
authors.affiliation: Johns Hopkins University, Baltimore, MD.
authors.forename: Tariq
authors.initials: T
authors.lastname: Shafi
authors.affiliation: Division of Nephrology, Tufts Medical Center, Boston, MA.
authors.forename: Aghogho
authors.initials: A
authors.lastname: Okparavero
authors.affiliation: Division of Nephrology, Tufts Medical Center, Boston, MA; The Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, MA; Tufts Clinical and Translational Science Institute, Tufts University, Boston, MA.
authors.forename: Hocine
authors.initials: H
authors.lastname: Tighiouart
authors.affiliation: Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN.
authors.forename: John H
authors.initials: JH
authors.lastname: Eckfeldt
authors.affiliation: University of Washington, Kidney Research Institute, Seattle, WA.
authors.forename: Ronit
authors.initials: R
authors.lastname: Katz
authors.affiliation: Department of Biostatistics, School of Public Health and Community Medicine, University of Washington, Seattle, WA.
authors.forename: W Craig
authors.initials: WC
authors.lastname: Johnson
authors.affiliation: Department of Biostatistics, School of Public Health and Community Medicine, University of Washington, Seattle, WA.
authors.forename: Norma
authors.initials: N
authors.lastname: Dermond
authors.affiliation: Johns Hopkins University, Baltimore, MD.
authors.forename: Zarqa
authors.initials: Z
authors.lastname: Tariq
authors.affiliation: Johns Hopkins University, Baltimore, MD.
authors.forename: Imene
authors.initials: I
authors.lastname: Benayache
authors.affiliation: Johns Hopkins University, Baltimore, MD.
authors.forename: Wendy S
authors.initials: WS
authors.lastname: Post
authors.affiliation: Johns Hopkins University, Baltimore, MD.
authors.forename: Josef
authors.initials: J
authors.lastname: Coresh
authors.affiliation: Division of Nephrology, Tufts Medical Center, Boston, MA.
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Levey
authors.affiliation: Division of Nephrology, University of California, San Francisco, CA.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Shlipak
mesh_terms: D000368:Aged; D050197:Atherosclerosis / Q000503:physiopathology; D044383:Black People; D003430:Cross-Sectional Studies; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012737:Sex Factors; D044465:White People
keywords: GFR decline trajectory; Glomerular filtration rate (GFR); albumin-creatinine ratio (ACR); albuminuria; body size; chronic kidney disease (CKD); ethnicity; health disparities; iohexol; measured GFR; race; racial differences; renal function; sex