Alzheimer’s experts revise guidelines for amyloid, tau PET utilization

Key takeaways:

• The revised criteria offer guidance for clinicians to determine when amyloid and tau PET are recommended.
• Criteria were divided into 17 common clinical scenarios with three subcategories of appropriateness.

Revised guidelines for amyloid and tau positron emission tomography for Alzheimer’s disease and dementia state these tests should only be ordered if the results will directly impact care, like when determining treatment eligibility.

The updated framework, which was published simultaneously in Alzheimer’s & Dementia as well as The Journal of Nuclear Medicine, cautions health care providers against using these imaging options for individuals without cognitive impairment, in lieu of genetic testing or for other nonmedical situations.

“Amyloid and tau PET can support and enable earlier and more accurate diagnosis, which is essential to high quality care and treatment for dementia, providing appropriate support services and future planning,” Gil D. Rabinovici, MD, lead author of the paper and Edward and Pearl Fein Distinguished Professor in memory and aging at the University of California, San Francisco, said in a related release. “The clinician should also take into consideration the person’s cognitive status and age, and work with the patient and family to decide whether these tests will be helpful.”

The Appropriate Use Criteria (AUC) are divided into 17 common clinical scenarios for which amyloid or tau PET imaging may be considered, with scores from one to nine assigned based on each scenario.

These revisions, the first since an initial AUC was released in 2013, were developed through a collaboration between the Alzheimer’s Association and the Society for Nuclear Medicine and Molecular Imaging. 

According to the workgroup, appropriate scenarios for amyloid and tau PET include:

• patients aged younger than 65 years who present with mild cognitive impairment or dementia and in whom AD pathology is suspected;
• those with either MCI or dementia consistent with AD pathology, with onset at age 65 years or older; and
• patients with MCI or dementia that may be consistent with AD pathology but has atypical features such as non-amnestic clinical presentation, rapid or slow disease progression.

Situations deemed rarely appropriate for both forms of imaging include:

• utilization to determine disease severity or track disease progression in patients whose biomarkers previously supported a diagnosis of either MCI or dementia due to AD pathology;
• individuals with prodromal Lewy body disease or dementia with Lewy bodies;
• patients diagnosed with MCI or dementia who possess recent conclusive cerebrospinal fluid biomarker results, regardless of consistency with AD pathology; and
• those deemed cognitively uncertain and not considered at increased risk for AD based on age, known APOE4 genotype or multigenerational family history, as well as those with subjective cognitive decline under similar criteria.

“With the recent approval of amyloid-targeting monoclonal antibodies, the field has entered a new era of molecular-specific therapies, and amyloid and tau PET are likely to play an increasingly important role in individuals being evaluated for these novel treatments,” Rabinovici and colleagues wrote. 

Reference:

New guidance for gold-standard imaging tests assists clinicians in diagnosis and management of Alzheimer’s and other dementia. https://www.alz.org/news/2025/updated-appropriate-use-criteria-amyloid-tau-pet. Published Jan. 8, 2025. Accessed Jan. 8, 2025.