Plasma biomarkers of astrocytic and neuronal dysfunction in early- and late-onset Alzheimer's disease.

Introduction: We investigated plasma proteomic markers of astrocytopathy, brain degeneration, plasticity, and inflammation in sporadic early-onset versus late-onset Alzheimer's disease (EOAD and LOAD).

Methods: Plasma was analyzed using ultra-sensitive immuno-based assays from 33 EOAD, 30 LOAD, and 36 functionally normal older adults.

Results: Principle component analyses identified 3 factors: trophic (BDNF, VEGF, TGFβ), degenerative (GFAP, NfL), and inflammatory (TNFα, IL-6, IP-10, IL-10).

Cognitive aging is not created equally: differentiating unique cognitive phenotypes in "normal" adults.

Age-related cognitive decline is a public health problem but highly diverse and difficult to predict. We captured nonoverlapping cognitive phenotypes in high-functioning adults and identified baseline factors differentiating trajectories. Three hundred fourteen functionally normal adults (M = 69 y) completed 2+ visits.