title: CRP polymorphisms and chronic kidney disease in the third national health and nutrition examination survey.
abstract: BACKGROUND
  CRP gene polymorphisms are associated with serum C-reactive protein concentrations and may play a role in chronic kidney disease (CKD) progression. We recently reported an association between the gene variant rs2808630 and CKD progression in African Americans with hypertensive kidney disease. This association has not been studied in other ethnic groups.
  
  
  METHODS
  We used data from 5955 participants from Phase 2 of The Third National Health and Nutrition Examination Survey (1991-1994) to study the association between CRP polymorphisms and CKD prevalence in a population-based sample. The primary outcome was CKD defined as estimated glomerular filtration rate (eGFR) <60 ml/min or the presence of albuminuria. Secondary outcomes were the presence of albuminuria (any degree) and continuous eGFR. Six single nucleotide polymorphisms (SNPs) from the CRP gene, rs2808630, rs1205, rs3093066, rs1417938, rs3093058, and rs1800947, were evaluated.
  
  
  RESULTS
  CRP rs2808630 AG compared to the referent AA genotype was associated with CKD in non-Hispanic blacks (n = 1649, 293 of whom had CKD) with an adjusted odds ratio (OR) of 3.09 (95% CI 1.65-5.8; p = 0.001). For the secondary outcomes, rs2808630 AG compared to the referent AA genotype was associated with albuminuria with an adjusted OR of 3.07 (95% CI 1.59-5.94; p = 0.002), however not with eGFR. There was no association between the SNPs and CKD, albuminuria or eGFR in non-Hispanic whites or Mexicans Americans.
  
  
  CONCLUSIONS
  In this cross-sectional study, the 3' flanking CRP gene variant rs2808630 was associated with CKD, mainly through its association with albuminuria in the non-Hispanic blacks. Despite not finding an association with eGFR, our results support our previous study demonstrating an association between CRP gene variant rs2808630 and CKD progression in a longitudinal cohort of African American with hypertensive kidney disease.
authors.affiliation: Veterans Administration Tennessee Valley Healthcare System Nashville, TN, USA. Adriana.hung@vanderbilt.edu
authors.forename: Adriana M
authors.initials: AM
authors.lastname: Hung
authors.forename: T Alp
authors.initials: TA
authors.lastname: Ikizler
authors.forename: Marie R
authors.initials: MR
authors.lastname: Griffin
authors.forename: Kimberly
authors.initials: K
authors.lastname: Glenn
authors.forename: Robert A
authors.initials: RA
authors.lastname: Greevy
authors.forename: Carlos G
authors.initials: CG
authors.lastname: Grijalva
authors.forename: Edward D
authors.initials: ED
authors.lastname: Siew
authors.forename: Dana C
authors.initials: DC
authors.lastname: Crawford
mesh_terms: D001741:Black or African American / Q000235:genetics; D000419:Albuminuria / Q000652:urine; D002097:C-Reactive Protein / Q000235:genetics*; D015331:Cohort Studies; D005260:Female; D055106:Genome-Wide Association Study; D005838:Genotype; D005919:Glomerular Filtration Rate; D006801:Humans; D007676:Kidney Failure, Chronic / Q000453:epidemiology* / Q000235:genetics*; D008297:Male; D017058:Mexican Americans / Q000235:genetics; D009749:Nutrition Surveys; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D015995:Prevalence; D014481:United States / Q000453:epidemiology; D044465:White People / Q000235:genetics
chemical_list: D002097:C-Reactive Protein