Associations Between Retinal Microvasculature Changes and Gray Matter Volume in a Mid-Life Cohort at Risk of Developing Alzheimer's Disease

Alzheimer's Disease (AD) presents a formidable global health challenge, with a predicted rise in affected individuals in the coming years. Consequently, the development of methods for early detection and monitoring methods are crucially important. Recent studies have highlighted the potential of retinal microvasculature changes captured through optical coherence tomography angiography (OCTA) as a promising tool to be further investigated for the early detection of asymptomatic AD. However, the relationship between retinal microvasculature changes and gray matter volume (GMV), a neuroimaging biomarker for symptomatic AD, is still vague when the disease is asymptomatic. This study investigates the potential associations between retinal microvasculature changes and gray matter volume (GMV) in a midlife cohort at risk of developing AD. The study investigated the potential association between OCTA metrics and GMV measures in participants (n = 108, mean age = 51 years old) with and without the known Apoliproprotein E4 (APOE4) gene. We observed that foveal avascular zone (FAZ) area and acircularity, foveal vessel skeleton density (FVSD), vessel graph density (VGD), vessel curvature and tortuosity showed significant correlations with various GMV regions. Our findings strengthen the potential for investigating retinal microvasculature changes for the early detection of AD.