Significance of a positive tau PET scan with a negative amyloid PET scan.
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ABSTRACT: Introduction
The implications of positive tau positron emission tomography (T) with negative beta amyloid positron emission tomography (A) are not well understood. We investigated cognitive performance in participants who were T+ but A-.Methods
We evaluated 98 participants from the Mayo Clinic who were T+ and A-. Participants were matched 2:1 to A- and T- cognitively unimpaired (CU) controls. Cognitive test scores were compared between different groups.Results
The A-T+ group demonstrated lower performance than the A-T- group on the Mini-Mental Status Exam (MMSE) (p < 0.001), Wechsler Memory Scale-Revised Logical Memory I (p < 0.001) and Logical Memory II (p < 0.001), Auditory Verbal Learning Test (AVLT) delayed recall (p = 0.004), category fluency (animals p = 0.005; vegetables p = 0.021), Trail Making Test A and B (p < 0.001), and others. There were no significant differences in demographic features or apolipoprotein E (APOE) e4 genotype between CU A-T+ and CI A-T+.Discussion
A-T+ participants show an association with lower cognitive performance.
SUBMITTER: Robinson CG
PROVIDER: S-EPMC10947949 | biostudies-literature | 2024 Mar
REPOSITORIES: biostudies-literature
Publications
Significance of a positive tau PET scan with a negative amyloid PET scan.
Robinson Carling G CG Lee Jeyeon J Min Paul H PH Przybelski Scott A SA Josephs Keith A KA Jones David T DT Graff-Radford Jonathan J Boeve Bradley F BF Knopman David S DS Jack Clifford R CR Petersen Ronald C RC Machulda Mary M MM Fields Julie A JA Lowe Val J VJ
Alzheimer's & dementia : the journal of the Alzheimer's Association 20231230 3
<h4>Introduction</h4>The implications of positive tau positron emission tomography (T) with negative beta amyloid positron emission tomography (A) are not well understood. We investigated cognitive performance in participants who were T+ but A-.<h4>Methods</h4>We evaluated 98 participants from the Mayo Clinic who were T+ and A-. Participants were matched 2:1 to A- and T- cognitively unimpaired (CU) controls. Cognitive test scores were compared between different groups.<h4>Results</h4>The A-T+ gr ...[more]
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