APOE and hippocampal atrophy: In this study, we examined non-demented Alzheimer’s Disease Neuroimaging Initiative (ADNI) participants to investigate the associations among age, vascular risk factors, WMH and plasma Aβ42/Aβ40, Aβ PET and their prediction of longitudinal WMH, cortical Aβ deposition, hippocampal atrophy, and cognitive decline in APOE-ε4 carriers and non-carriers.