title: Uromodulin concentrations are not associated with incident CKD among persons with coronary artery disease.
abstract: BACKGROUND
  A common variant of the UMOD gene was linked with prevalent chronic kidney disease (CKD) in large, genomics consortia. One community-based study found that urine concentrations of the uromodulin protein forecast risk of incident CKD. This study within persons with known coronary artery disease (CAD) evaluated whether uromodulin concentrations could distinguish CKD risk.
  
  
  METHODS
  In the Heart and Soul Study, the UMOD snp (12917707) was genotyped in 879 individuals with baseline creatinine clearance (CrCl) measured from a 24-hour urine collection. Uromodulin protein was measured from stored urine specimens among a subset of 120 participants, balanced by genotype. Incident CKD cases (N = 102) were defined by an initial CrCl > 70 ml/min and a 5-year follow-up CrCl <60 ml/min; controls (N = 94) were matched on age, sex, and race.
  
  
  RESULTS
  Among 527 self-described White participants with DNA, 373 (71%) were homozygous for the dominant allele (G/G), 133 (25%) were heterozygous (G/T) and only 21 (4%) were homozygous for the minor allele (T/T). The T/T genotype had an approximately 11 ml/min higher CrCl than the other 2 groups, but this difference did not reach statistical significance (p = 0.20). The T/T genotype had significantly lower uromodulin levels than the common G/G genotype, and the G/T genotype had intermediate levels. However, uromodulin concentrations were similar between cases and controls (44 vs. 48 mg/dL, p = 0.88).
  
  
  CONCLUSIONS
  This study among a cohort of persons with established CAD found no association between urine uromodulin and incident CKD, although UMOD genotype was associated with urine uromodulin concentrations.
authors.affiliation: San Francisco VA Medical Center, CA, USA. michael.shlipak@ucsf.edu
authors.forename: Michael G
authors.initials: MG
authors.lastname: Shlipak
authors.forename: Yongmei
authors.initials: Y
authors.lastname: Li
authors.forename: Caroline
authors.initials: C
authors.lastname: Fox
authors.forename: Josef
authors.initials: J
authors.lastname: Coresh
authors.forename: Carl
authors.initials: C
authors.lastname: Grunfeld
authors.forename: Mary
authors.initials: M
authors.lastname: Whooley
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D015897:Comorbidity; D003324:Coronary Artery Disease / Q000097:blood* / Q000453:epidemiology* / Q000235:genetics; D005260:Female; D006801:Humans; D015994:Incidence; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000453:epidemiology* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D012495:San Francisco / Q000453:epidemiology; D012680:Sensitivity and Specificity; D058949:Uromodulin / Q000097:blood* / Q000235:genetics*
chemical_list: D015415:Biomarkers; D058949:Uromodulin