title: Phenotypic and genetic relationships between kidney function and carotid intima-media thickness in Koreans: the Healthy Twin Study.
abstract: BACKGROUND
  The phenotypic and genetic relationships between carotid intima-media thickness (CIMT) and estimated glomerular filtration rate (eGFR) or urinary albumin-creatinine ratio (ACR) were evaluated in Korean twins and families.
  
  
  METHODS
  We recruited 688 participants (296 individual twins and 392 singletons, age 30-74 years) who were without myocardial infarction and stroke among participants in the Healthy Twin Study. eGFR was calculated using the Chronic Kidney Disease Epidemiology Collaboration equation. CIMT was measured using B-mode carotid ultrasound. Covariates were sex, Framingham risk scores, alcohol use, exercise, BMI, high-sensitivity C-reactive protein and triglycerides. Quantitative genetic and linear mixed analyses were performed.
  
  
  RESULTS
  In adjusted models there were associations between kidney function and CIMT with [beta] estimates ranging from -0.022 to -0.032 between eGFR and CIMT, and from 0.042-0.060 between ACR and CIMT. The covariate-adjusted heritabilities for eGFR, ACR and composite CIMT were 0.75, 0.32 and 0.45, respectively (p < 0.001). The adjusted genetic correlation between eGFR and CIMT was from -0.20 to -0.28 (p < 0.05), whereas there was no genetic correlation between ACR and CIMT.
  
  
  CONCLUSIONS
  Kidney function is a surrogate marker of carotid atherosclerosis and further studies of the pleiotropic relationships between CIMT and eGFR are warranted.
authors.affiliation: Department of Family Medicine, Busan Paik Hospital, Inje University College of Medicine, Seoul, Korea.
authors.forename: Kayoung
authors.initials: K
authors.lastname: Lee
authors.forename: Joohon
authors.initials: J
authors.lastname: Sung
authors.forename: Sang Cheol
authors.initials: SC
authors.lastname: Lee
authors.forename: Seung Woo
authors.initials: SW
authors.lastname: Park
authors.forename: Youn Sic
authors.initials: YS
authors.lastname: Kim
authors.forename: Joo Yeon
authors.initials: JY
authors.lastname: Lee
authors.forename: Yun-Mi
authors.initials: YM
authors.lastname: Song
mesh_terms: D000328:Adult; D000368:Aged; D044466:Asian People / Q000235:genetics*; D059168:Carotid Intima-Media Thickness; D005260:Female; D020022:Genetic Predisposition to Disease; D005919:Glomerular Filtration Rate / Q000235:genetics; D006801:Humans; D007668:Kidney / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D012307:Risk Factors