The retina at the back of the eye is the one part of the central nervous system that can be readily visually inspected, including the state of the network of blood vessels that supports it. Capillary networks of tiny blood vessels are dense and actively maintained; as the character of angiogenesis changes for the worse with aging, these networks become less dense and exhibit other signs of damage. Thus imagery of the retina provides a lot of data that can be employed to, for example, produce aging clocks, or act as a proxy measure for other forms of vascular and nervous system aging.
For retinal imagery to be usefully employed as a proxy measure of any specific aspect of vascular aging or central nervous system aging, or specific form of age-related damage, a robust correlation must first be demonstrated. Thus we have papers such as today's example, in which researchers establish links between retinal imagery characteristics and vascular and brain aging. One might expect this to inform efforts to further advance retinal imaging as a relatively low cost diagnostic tool, a way to better establish risk and the need for more costly forms of assessment in older people.
Doctors often use eye scans to check for signs of heart and brain disease, but the exact link between the tiny blood vessels in the eye and those in major organs is unclear. We aimed to systematically map similarities between blood vessels across the entire body. We compared vascular image-derived phenotypes from the brain, carotid artery, aorta, and retina, using UK Biobank sample sizes ranging from 18,808 to 68,740 participants. We examined phenotypic and genetic correlations, as well as common associated genes and pathways.
Here we show that white matter hyperintensities are positively correlated with carotid intima-media thickness (r = 0.03), lumen diameter (r = 0.14), and aortic cross-sectional areas (r = 0.09), but negatively correlated with aortic distensibilities (r ≤ -0.05). Arterial retinal vascular density shows negative correlations with white matter hyperintensities (r = -0.04), intima-media thickness (r = -0.04), lumen diameter (r = -0.06), and aortic areas (r = -0.05), while positively correlating with aortic distensibilities (r = 0.04). Significant correlations also persist after correcting for hypertension.
In summary, we found strong connections with the health of retinal blood vessels mirroring the health of the brain and major arteries. This suggests that some of the same factors influence vessel health across the body. This suggests that an eye scan could be a fast, non-invasive way to get a complete snapshot of a person's overall cardiovascular and brain health. These findings could help doctors identify health issues, such as early artery stiffness or brain aging, much sooner.
View the full article at FightAging
