title: Structural changes in the retinal microvasculature and renal function.
abstract: OBJECTIVE
  To evaluate the associations between chronic kidney disease (CKD) and microalbuminuria, and a comprehensive range of retinal microvascular abnormalities including traditional and new retinal vascular measures.
  
  
  METHODS
  This was a population-based, cross-sectional study on 3280 urban Malay adults. The albumin/creatinine ratio (ACR) was calculated from spot urine samples. Estimated glomerular filtration rate (eGFR) was calculated from serum creatinine concentration. Retinal vascular caliber and geometry were quantified from retinal fundus photographs using a semiautomated computer-assisted program. Qualitative changes including focal arteriolar narrowing, arteriovenous nicking, and opacification of the arteriolar wall were assessed by trained graders.
  
  
  RESULTS
  In multivariate analyses adjusting for age, sex, hypertension, diabetes, and smoking, narrower retinal arteriolar caliber (P = 0.008), smaller retinal vascular fractal dimensions (P = 0.014), and the presence of AV nicking and opacification (P = 0.005 and P < 0.001, respectively) were significantly associated with lower eGFR. In multivariate adjusted logistic regression analyses, none of the retinal markers was associated with CKD. A smaller fractal dimension (P < 0.001) and the presence of focal arteriolar narrowing, AV nicking and opacification were associated with higher ACR (P < 0.001, P = 0.01, and P = 0.002, respectively). Narrower retinal arterioles (P = 0.041); smaller fractal dimensions (P = 0.006); and focal arteriolar narrowing, AV nicking, and opacification (P = 0.007, P = 0.007, and P = 0.012, respectively) were associated with higher likelihoods of having microalbuminuria.
  
  
  CONCLUSIONS
  Quantitative changes of the retinal vascular geometry and qualitative changes in the vessel architecture are associated with markers of renal dysfunction and damage.
authors.affiliation: Singapore Eye Research Institute, Singapore National Eye Centre, Singapore. ophwty@nus.edu.sg
authors.forename: Laurence Shen
authors.initials: LS
authors.lastname: Lim
authors.forename: Carol Yim-Lui
authors.initials: CY
authors.lastname: Cheung
authors.forename: Charumathi
authors.initials: C
authors.lastname: Sabanayagam
authors.forename: Su Chi
authors.initials: SC
authors.lastname: Lim
authors.forename: E Shyong
authors.initials: ES
authors.lastname: Tai
authors.forename: Lei
authors.initials: L
authors.lastname: Huang
authors.forename: Tien Yin
authors.initials: TY
authors.lastname: Wong
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000419:Albuminuria; D002908:Chronic Disease; D003404:Creatinine / Q000652:urine; D003430:Cross-Sectional Studies; D005919:Glomerular Filtration Rate; D006801:Humans; D007674:Kidney Diseases / Q000175:diagnosis*; D008875:Middle Aged; D015999:Multivariate Analysis; D010781:Photography; D012171:Retinal Vessels / Q000473:pathology*
chemical_list: D003404:Creatinine