MAPT and diabetes mellitus: Although brain volume changes in areas such as the hippocampus and middle temporal lobe are observed in association with diabetes mellitus and insulin resistance in midlife [43, 44], in a sample of middle-aged to older non-demented adults, no difference was observed in amyloid PET SUVRs or amyloid PET-positivity between diabetic and non-diabetic groups, while only among the amyloid PET-positive participants, tau PET SUVRs were higher in the diabetic group compared to non-diabetic group [45].