Cognitive deficits in non-demented diabetic elderly appear independent of brain amyloidosis

Background: To determine the effects of Type 2 diabetes (DM2) on levels of brain amyloidosis and cognition in a community-dwelling cohort of nondemented elderly individuals. Methods: 33 subjects (16 DM2, 17 nondiabetic) were prospectively recruited. Subjects underwent a PET scan using the amyloid tracer, Pittsburgh Compound B, and a neuropsychological evaluation. Associations between DM2, brain amyloidosis, and cognition were assessed using multivariate regressions, adjusting for age and APOE4 status. Results: DM2 subjects had lower global cognitive function (p = 0.018), as measured by the Repeatable Battery for the Assessment of Neuropsychological Status. There was no difference in brain amyloidosis between groups (p = 0.25). Conclusions: Community-dwelling, nondemented individuals with DM2 had greater cognitive deficits, which do not appear to be mediated by brain amyloidosis. Further studies exploring potential mediators of these cognitive deficits should be performed. (C) 2016 Elsevier B.V. All rights reserved.