SIX4 and Alzheimer disease: The miR-375/SIX4 regulatory axis was investigated using bioinformatics prediction, biotin-RNA pull-down, dual-luciferase reporter assays, and co-transfection experiments.<h4>Results</h4>Compared to MCI and NCI groups, AD patients exhibited significantly higher baPWV and lower levels of EPC-Exosomal hsa_circ_0093884 (<i>P</i> < 0.01).