title: Association between carotid intima-media thickness and retinal arteriolar and venular diameter in patients with hypertension: a cross-sectional study.
abstract: OBJECTIVE
  Abnormalities in retinal vessels are frequent, but its association with findings in other vascular sites has been scarcely investigated. This study aimed to examine the association between ultrasound-measured carotid intima-media thickness (IMT) and retinal arteriolar and venular diameters, in hypertensive patients.
  
  
  METHODS
  In this cross-section study, 173 hypertensive patients had both retinography taken and digitized to determine vessel diameters by an edge-detecting computerized method and carotid ultrasound for semi-automated carotid IMT measurement. The association between the mean common carotid IMT and retinal arterioles and venules diameters was assessed by using multiple linear regression models.
  
  
  RESULTS
  The mean (±SD) arteriolar and venular diameters were 102. 8 (±11.6) μm and 128.9 (±15.5) μm, respectively, and common carotid IMT was 0.87 (±0.19) mm. A significant and independent association was demonstrated for carotid IMT and retinal arteriolar caliber (adjusted β -0.245, p = 0.001) and for carotid IMT and retinal venular caliber (adjusted β 0.191, p = 0.009) after controlling for age, gender, systolic blood pressure, total cholesterol and HDL (high-density lipoprotein) cholesterol, prior cardiovascular disease, carotid plaque and the retinal fellow vessel.
  
  
  CONCLUSIONS
  In patients with hypertension, carotid intima-media thickness, a marker of macrovascular damage, is significantly and independently associated with microvascular damage, determined by retinal arteriolar and venular calibers.
authors.affiliation: Postgraduate Studies Program in Cardiology, School of Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. felipesoarestorres@gmail.com
authors.forename: Felipe Soares
authors.initials: FS
authors.lastname: Torres
authors.forename: Sandra C
authors.initials: SC
authors.lastname: Fuchs
authors.forename: Marcelo K
authors.initials: MK
authors.lastname: Maestri
authors.forename: Flavio D
authors.initials: FD
authors.lastname: Fuchs
authors.forename: Manuel M
authors.initials: MM
authors.lastname: Oliveira
authors.forename: Leila B
authors.initials: LB
authors.lastname: Moreira
authors.forename: Miguel
authors.initials: M
authors.lastname: Gus
mesh_terms: D000368:Aged; D001160:Arterioles / Q000000981:diagnostic imaging; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging*; D059168:Carotid Intima-Media Thickness; D003430:Cross-Sectional Studies; D003720:Densitometry / Q000379:methods / Q000592:standards / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D006973:Hypertension / Q000000981:diagnostic imaging* / Q000453:epidemiology; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011859:Radiography; D015203:Reproducibility of Results; D012171:Retinal Vessels / Q000000981:diagnostic imaging*; D012307:Risk Factors; D014699:Venules / Q000000981:diagnostic imaging