# Cross-organ analysis reveals associations between vascular properties of the retina, the carotid and aortic arteries, and the brain

## TL;DR

Eye blood vessel health reflects brain and major artery health, suggesting shared genetic factors and potential for early disease detection.

## Contribution

Systematic mapping of cross-organ vascular correlations and shared genetic influences using large-scale imaging data.

## Key findings

- Retinal vascular density correlates with brain white matter and aortic artery properties.
- Shared genetic factors influence vascular morphology across multiple organs.
- Correlations persist even after adjusting for hypertension.

## Abstract

Vascular properties of the retina are indicative of both ocular and systemic cardio- and cerebrovascular health. However, the specific relationships between retinal and non-retinal vascular phenotypes have not been systematically investigated in large samples. This study aims to compare cross-organ phenotypic and genetic relationships between vascular characteristics across different body sites.

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.

Our findings shed light on the complex interplay between vascular morphology across different organs, revealing both shared and distinct genetic underpinnings. Retinal vascular features reflect broader systemic vascular morphology and offer an accessible window into cardio- and cerebrovascular health.

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 analyzed medical scans of the retina, brain and major arteries (carotid and aorta) from a large group of people from the UK. We looked for similarities between blood vessel properties in different organs and studied to what extent they are inherited. 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.

Ortín Vela and Bergmann compare vascular image derived phenotypes across the retina, brain, carotid artery and aorta in the UK Biobank. Retinal vessel health is indicative of the health of major arteries and brain vessels, revealing shared genetic influences.