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bioRxiv · 10.1101/611186

Tau pathology in cognitively normal older adults: Associations with brain atrophy and cognitive decline

Ziontz, J.·Bilgel, M.·Shafer, A.·Moghekar, A.·Elkins, W.·Helphrey, J.·Gomez, G.·June, D.·McDonald, M. A.·Dannals, R. F.·Azad, B. B.·Ferrucci, L.·Wong, D. F.·Resnick, S. M.
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Abstract

INTRODUCTIONTau pathology, a hallmark of Alzheimers disease, is observed in the brains of virtually all individuals over 70.\n\nMETHODSUsing 18F-AV-1451 (18F-flortaucipir) PET, we evaluated tau pathology in 54 cognitively normal participants (mean age 77.5, SD 8.9) from the Baltimore Longitudinal Study of Aging. We assessed associations between PET signal and age, sex, race, and amyloid positivity. We investigated relationships between regional signal and retrospective rates of change in regional volumes and cognitive function adjusting for age, sex, and amyloid status.\n\nRESULTSGreater age, male sex, black race, and amyloid positivity were associated with higher 18F-AV-1451 retention in distinct brain regions. Retention in the entorhinal cortex was associated with lower entorhinal volume ({beta} = -1.124, SE = 0.485, p = 0.025) and a steeper decline in memory performance ({beta} = -0.086, SE = 0.039, p = 0.029).\n\nDISCUSSIONAssessment of medial temporal tau pathology will provide insights into early structural brain changes associated with later cognitive impairment and Alzheimers disease.

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Ziontz, J., Bilgel, M., Shafer, A., Moghekar, A., Elkins, W., Helphrey, J., Gomez, G., June, D., McDonald, M. A., Dannals, R. F., Azad, B. B., Ferrucci, L., Wong, D. F., Resnick, S. M.. 2019-04-26. Tau pathology in cognitively normal older adults: Associations with brain atrophy and cognitive decline. https://doi.org/10.1101/611186

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