Impact of tau and amyloid burden on glucose metabolism in Alzheimer's disease

In a multimodal PET imaging approach, we determined the differential contribution of neurofibrillary tangles (measured with [F-18]AV-1451) and beta-amyloid burden (measured with [C-11]PiB) on degree of neurodegeneration (i.e., glucose metabolism measured with [F-18]FDG-PET) in patients with Alzheimer's disease. Across brain regions, we observed an interactive effect of beta-amyloid burden and tau deposition on glucose metabolism which was most pronounced in the parietal lobe. Elevated beta-amyloid burden was associated with a stronger influence of tau accumulation on glucose metabolism. Our data provide the first in vivo insights into the differential contribution of A and tau to neurodegeneration in Alzheimer's disease