Retinal Vascular Study Using OCTA in Subjects at High Genetic Risk of Developing Alzheimer's Disease and Cardiovascular Risk Factors

In 103 subjects with a high genetic risk of developing Alzheimer's disease (AD), family history (FH) of AD and ApoE e4 characterization (ApoE e4) were analyzed for changes in the retinal vascular network by OCTA (optical coherence tomography angiography), and AngioTool and Erlangen-Angio-Tool (EA-Tool) as imaging analysis software. Retinal vascularization was analyzed by measuring hypercholesterolemia (HCL) and high blood pressure (HBP). Angio-Tool showed a statistically significant higher percentage of area occupied by vessels in the FH+ ApoE e4- group vs. in the FH+ ApoE e4+ group, and EA-Tool showed statistically significant higher vascular densities in the C3 ring in the FH+ ApoE e4+ group when compared with: i)FH- ApoE e4- in sectors H3, H4, H10 and H11; and ii) FH+ ApoE e4- in sectors H4 and H12. In participants with HCL and HBP, statistically significant changes were found, in particular using EA-Tool, both in the macular area, mainly in the deep plexus, and in the peripapillary area. In conclusion, OCTA in subjects with genetic risk factors for the development of AD showed an apparent increase in vascular density in some sectors of the retina, which was one of the first vascular changes detectable. These changes constitute a promising biomarker for monitoring the progression of pathological neuronal degeneration.

Automated summary

By using optical coherence tomography angiography (OCTA) analysis, it was discovered that patients with a high genetic risk of developing Alzheimer's disease showed a significant increase in retinal vascular density, which may serve as one of the earliest detectable vascular changes and a promising biomarker for monitoring disease progression.