Stage-dependent agreement between cerebrospinal fluid proteins and FDG-PET findings in Alzheimer's disease.

Cerebral hypometabolism and abnormal levels of amyloid beta (Aβ), total (t-tau) and phosphorylated tau (ptau) proteins in cerebrospinal fluid (CSF) are established biomarkers of Alzheimer's disease (AD). We examined the agreement between these biomarkers in a single center study of patients with AD of severity extending over a wide range. Forty seven patients (MMSE 21.4 ± 3.6, range 13-28 points) with incipient and probable AD underwent positron emission tomography with [18F]-fluorodeoxyglucose (FDG-PET) and lumbar puncture for CSF assays of Aβ1-42, p-tau181, and t-tau. All findings were classified as either positive or negative for AD. Statistical analyses were performed for the whole samp…