Abnormalities in retinal vascular parameters (RVPs) may indicate increased amyloid plaque in the brain and can serve as biomarkers for preclinical Alzheimer's disease (AD), new research suggests.
Findings from the Australian Imaging, Biomarkers, and Lifestyle (AIBL) Flagship Study of Ageing showed that participants with AD had several significantly different RVPs, including narrower veins and a significantly higher arteriole-to-venule ratio (AVR), than their peers without AD.
In additional analysis of just the participants without an AD diagnosis, Pittsburgh Compound B positron emission tomography (PiB-PET) imaging showed that participants who had high neocortical plaque burden also had some of these RVP changes, possibly representing preclinical AD.
"This is the first study to investigate retinal blood vessel changes with respect to amyloid plaque burden in the brain," write the investigative team, led by Shaun Frost, a PhD candidate at the Commonwealth Scientific and Industrial Research Organization in Perth, Australia.
"Models combining RVPs perform well at distinguishing diagnosed AD patients from healthy controls," they add.