Retinal vascular caliber is associated with cardiovascular biomarkers of oxidative stress and inflammation: the POLA study

Abstract

Purpose: Retinal vascular caliber has been linked with increased cardiovascular risk and is predictive of cardiovascular pathology, including stroke and coronary heart disease. Oxidative stress, as well as inflammatory mechanisms, plays a major role in the pathogenesis and progression of atherosclerosis, plaque rupture and vascular thrombotic propensity. The purpose of this study is to explore the relationship between retinal vascular calibers and biomarkers of oxidative stress and inflammation, in subjects free of cardiovascular pathology.

Patients and methods: Cross-sectional analysis from a community-dwelling cohort comprising 1224 individuals aged 60 years and over, without a history of coronary or peripheral artery disease or stroke. Retinal vascular caliber was measured from fundus photographs using semi-automated standardized imaging software. Oxidative stress was evaluated using plasma superoxide dismutase 2 and glutathione peroxidase (GPx-3) activities, and inflammatory state was assessed using plasma high sensitivity C-reactive protein (hsCRP) and orosomucoid.

Results: In a multivariate model controlling for cardiovascular risk factors, larger retinal arteriolar caliber was independently related to higher level of GPx-3 activity (p = 0.003) whereas larger venular caliber was associated with higher levels of hsCRP (p = 0.0001) and orosomucoid (p = 0.01).

Conclusion: In the present study, biomarkers of oxidative stress regulation and inflammation were independently associated with retinal vascular calibers. This suggests that an assessment of retinal vessels may offer early and non-invasive detection of subclinical vascular pathology.

Figure 1. Mean + standard error retinal arteriolar caliber according to quartiles of plasma glutathione peroxidase activity, adjusted for age (years), gender (male vs. female), hypertension status (hypertensive vs. normotensive), current smoking status (current vs. never/past), body mass index (kg/m²), high-density-lipoprotein cholesterol (mmol/l), estimated glomerular filtration rate (Modification of the Diet in Renal Disease, ml/min/1.73m²), logarithmic of high-sensitivity C-Reactive Protein. P-value for the analysis of covariance (ANCOVA) = 0.003.