APOE and diabetes mellitus: A meta-analysis of risk factors that predict progression from mild MCI to AD included: APOE4, CSF tau levels, atrophy of the hippocampus and temporal lobe and entorhinal cortex, diabetes mellitus, high blood pressure, increasing age, traumatic brain injury (TBI), and female sex (Li et al., 2015; Graham et al., 2022; Mielke et al., 2022).