title: Urine arsenic and prevalent albuminuria: evidence from a population-based study.
abstract: BACKGROUND
  Long-term arsenic exposure is a major global health problem. However, few epidemiologic studies have evaluated the association of arsenic with kidney measures. Our objective was to evaluate the cross-sectional association between inorganic arsenic exposure and albuminuria in American Indian adults from rural areas of Arizona, Oklahoma, and North and South Dakota.
  
  
  METHODS
  Cross-sectional. SETTING & PARTIPANTS: Strong Heart Study locations in Arizona, Oklahoma, and North and South Dakota. 3,821 American Indian men and women aged 45-74 years with urine arsenic and albumin measurements.
  
  
  METHODS
  Urine arsenic.
  
  
  RESULTS
  Urine albumin-creatinine ratio and albuminuria status.
  
  
  METHODS
  Arsenic exposure was estimated by measuring total urine arsenic and urine arsenic species using inductively coupled plasma mass spectrometry (ICPMS) and high-performance liquid chromatography-ICPMS, respectively. Urine albumin was measured by automated nephelometric immunochemistry.
  
  
  RESULTS
  The prevalence of albuminuria (albumin-creatinine ratio ≥30 mg/g) was 30%. Median value for the sum of inorganic and methylated arsenic species was 9.7 (IQR, 5.8-15.6) μg per gram of creatinine. Multivariable-adjusted prevalence ratios of albuminuria (albumin-creatinine ratio ≥30 mg/g) comparing the 3 highest to lowest quartiles of the sum of inorganic and methylated arsenic species were 1.16 (95% CI, 1.00-1.34), 1.24 (95% CI, 1.07-1.43), and 1.55 (95% CI, 1.35-1.78), respectively (P for trend <0.001). The association between urine arsenic and albuminuria was observed across all participant subgroups evaluated and was evident for both micro- and macroalbuminuria.
  
  
  CONCLUSIONS
  The cross-sectional design cannot rule out reverse causation.
  
  
  CONCLUSIONS
  Increasing urine arsenic concentrations were cross-sectionally associated with increased albuminuria in a rural US population with a high burden of diabetes and obesity. Prospective epidemiologic and mechanistic evidence is needed to understand the role of arsenic as a kidney disease risk factor.
authors.affiliation: Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA.
authors.forename: Laura Y
authors.initials: LY
authors.lastname: Zheng
authors.forename: Jason G
authors.initials: JG
authors.lastname: Umans
authors.forename: Maria
authors.initials: M
authors.lastname: Tellez-Plaza
authors.forename: Fawn
authors.initials: F
authors.lastname: Yeh
authors.forename: Kevin A
authors.initials: KA
authors.lastname: Francesconi
authors.forename: Walter
authors.initials: W
authors.lastname: Goessler
authors.forename: Ellen K
authors.initials: EK
authors.lastname: Silbergeld
authors.forename: Eliseo
authors.initials: E
authors.lastname: Guallar
authors.forename: Barbara V
authors.initials: BV
authors.lastname: Howard
authors.forename: Virginia M
authors.initials: VM
authors.lastname: Weaver
authors.forename: Ana
authors.initials: A
authors.lastname: Navas-Acien
mesh_terms: D000368:Aged; D000419:Albuminuria / Q000453:epidemiology / Q000652:urine*; D001151:Arsenic / Q000652:urine*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D001151:Arsenic