Could PET Imaging Stage Alzheimer's Disease?
HealthDay News — Use of [18F]-AV-1451 positron emission tomography (PET) can potentially stage Alzheimer's disease (AD), according to a study published online July 25 in JAMA Neurology.
In an effort to assess the usefulness of [18F]-AV-1451 PET imaging to stage AD, Liang Wang, MD, from Washington University in St. Louis, and colleagues conducted an imaging study among 59 participants who were cognitively normal (CN) or had AD dementia.
The researchers found that the [18F]-AV-1451 standardized uptake value ratio (SUVR) in the hippocampus and AD cortical signature regions was able to differentiate AD from CN participants (area under the receiver operating characteristic curve range, 0.89 to 0.98). Cerebrospinal fluid Aβ42-positive (Aβ+) AD was best separated from cerebrospinal fluid Aβ42-negative CN participants at an [18F]-AV-1451 SUVR cut-off of 1.19 from AD cortical signature regions (sensitivity, 100%; specificity, 86%). This cut-off was also able to divide Aβ+ CN participants into high or low tau groups. In AD cortical signature regions, but not the hippocampus, the presence of Aβ+ correlated with elevated [18F]-AV-1451 SUVR. In both the hippocampus and AD cortical signature regions, an elevated [18F]-AV-1451 correlated with volumetric loss. In the hippocampus, but not AD cortical signature regions, the [18F]-AV-1451 volumetric association was modified by Aβ status.
"Aβ interacts with hippocampal and cortical tauopathy to affect neurodegeneration," the authors write. "In the absence of Aβ, hippocampal tau deposition may be insufficient for the neurodegenerative process that leads to AD."
Several authors disclosed financial ties to pharmaceutical companies, including Avid Radiopharmaceuticals, a wholly owned subsidiary of Eli Lilly, which provided AV-1451, radiochemistry support, and cross-referencing of the investigational new drug application.