Amyloid-β associated volume loss occurs only in the presence of phospho-tau.

The relationship between neurodegeneration and the 2 hallmark proteins of Alzheimer's disease, amyloid-β (Aβ) and tau, is still unclear. Here, we examined 286 nondemented participants (107 cognitively normal older adults and 179 memory impaired individuals) who underwent longitudinal magnetic resonance (MR) imaging and lumbar puncture. Using mixed effects models, we investigated the relationship between longitudinal entorhinal cortex atrophy rate, cerebrospinal fluid (CSF) p-tau(181p) and CSF Aβ(1-42) . We found a significant relationship between elevated entorhinal cortex atrophy rate and decreased CSF Aβ(1-42) only with elevated CSF p-tau(181p) . Our findings indicate that Aβ-associated volume loss occurs only in the presence of phospho-tau in humans at risk for dementia.