Finding the clues: What retinal vasculature changes may mean for cognitive impairment

An international team of investigators, led by Emma Pead, reported that changes in the vasculature of the peripheral retina may hold clues to the development of cognitive impairment and may be useful surrogate measures of cognitive decline.¹

The study found differences in the retinal vasculature in patients with Alzheimer’s dementia and mild cognitive impairment. She is with the VAMPIRE Project, Centre for Clinical Brain Sciences, The University of Edinburgh, Edinburgh, UK.

She and her colleagues conducted a pilot study in which they used ultra-widefield retinal imaging to assess the presence of abnormalities in the retinal vasculature in patients with Alzheimer's dementia and mild cognitive impairment (MCI) and compared them with participants with normal cognition.

A total of 103 individuals were included in the study: 28 had Alzheimer’s dementia, 30 mild cognition impairment, and 45 normal cognition. The images obtained from the patients underwent analysis to quantify the retinal vascular branching complexity, width, and tortuosity, Ms. Pead explained.

Imaging findings in cognitive impairment

The investigators reported increased vessel branching in the midperipheral retina and increased arteriolar thinning in those with Alzheimer's dementia. Increased rates of arteriolar and venular thinning were seen in patients with mild cognitive impairment as well as a trend toward decreased vessel branching.

The investigators concluded thatthe distinct cognitive states showed significant differences in the retinal vasculature in the peripheral retina. However, they also advised that larger studies are needed to establish the clinical relevance of their findings.

They believe that ultra-widefield imaging may be a promising technology for assessing larger areas of the retinal vasculature to uncover retinal changes in Alzheimer’s disease.

Reference

1. Pead E, Thompson AC, Grewal DS, et al. Retinal vascular changes in Alzheimer’s dementia and mild cognitive impairment: a pilot study using ultra-widefield imaging. Transl Vis Sci Technol. 2023;12:13; doi:10.1167/tvst.12.1.13