title: Systemic circulatory influences on retinal microvascular function in middle-age individuals with low to moderate cardiovascular risk.
abstract: OBJECTIVE
  To investigate the relationship between retinal microvascular reactivity, circulatory markers for CVD risk and systemic antioxidative defence capacity in healthy middle-aged individuals with low to moderate risk of CVD.
  
  
  METHODS
  Retinal vascular reactivity to flickering light was assessed in 102 healthy participants (46-60 years) by means of dynamic retinal vessel analysis (DVA). Other vascular assessments included carotid intima-media thickness (C-IMT) and blood pressure (BP) measurements. Total cholesterol (CHOL), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG) and blood glutathione levels in its reduced (GSH) and oxidized (GSSG) forms were also determined for each participant, along with Framingham risk scores (FRS).
  
  
  RESULTS
  Retinal arterial baseline diameter fluctuation (BDF) was independently, significantly and negatively influenced by LDL-C levels (β = -0.53, p = 0.027). Moreover, the arterial dilation slope (SlopeAD ) was independently, significantly and positively associated with redox index (GSH: GSSG ratio, β = 0.28, p = 0.016), while the arterial constriction slope (SlopeAC ) was significantly and negatively influenced by blood GSH levels (β = -0.20, p = 0.042), and positively associated with FRS (β = 0.25, p = 0.009). Venous BDF and dilation amplitude (DA) were also negatively influenced by plasma LDL-C levels (β = -0.83, p = 0.013; and β = -0.22, p = 0.028, respectively).
  
  
  CONCLUSIONS
  In otherwise healthy individuals with low to moderate cardiovascular risk, retinal microvascular dilation and constriction responses to stress levels are influenced by systemic antioxidant capacity, and circulating markers for cardiovascular risk.
authors.affiliation: Vascular Research Laboratory, Ophthalmic Research Group, School of Life and Health Sciences, Aston University, Birmingham, UK.
authors.forename: Swathi
authors.initials: S
authors.lastname: Seshadri
authors.affiliation: Vascular Research Laboratory, Ophthalmic Research Group, School of Life and Health Sciences, Aston University, Birmingham, UK.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Mroczkowska
authors.affiliation: Vascular Research Laboratory, Ophthalmic Research Group, School of Life and Health Sciences, Aston University, Birmingham, UK.
authors.forename: Lu
authors.initials: L
authors.lastname: Qin
authors.affiliation: Vascular Research Laboratory, Ophthalmic Research Group, School of Life and Health Sciences, Aston University, Birmingham, UK.
authors.forename: Sunni
authors.initials: S
authors.lastname: Patel
authors.affiliation: School of Engineering and Applied Sciences, Aston University, Birmingham, UK.
authors.forename: Aniko
authors.initials: A
authors.lastname: Ekart
authors.affiliation: Vascular Research Laboratory, Ophthalmic Research Group, School of Life and Health Sciences, Aston University, Birmingham, UK.
authors.forename: Doina
authors.initials: D
authors.lastname: Gherghel
mesh_terms: D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure / Q000502:physiology; D002318:Cardiovascular Diseases / Q000503:physiopathology*; D059168:Carotid Intima-Media Thickness; D002784:Cholesterol / Q000097:blood; D005260:Female; D005978:Glutathione / Q000097:blood; D006801:Humans; D008297:Male; D055806:Microvessels; D008875:Middle Aged; D018384:Oxidative Stress; D012171:Retinal Vessels / Q000503:physiopathology*; D012307:Risk Factors
chemical_list: D015415:Biomarkers; D002784:Cholesterol; D005978:Glutathione
keywords: cardiovascular risk; dynamic retinal vessel analysis; oxidative stress; retina; vascular function