Alzheimer’s: Biomarkers, not cognition, will now define disorder

April 10, 2018|Neurology

FROM ALZHEIMER’S & DEMENTIA

The biomarker profiles are:

A-T-(N): Normal AD biomarkers
A+T-(N): Alzheimer’s pathologic change; Alzheimer’s continuum
A+T+(N): Alzheimer’s disease; Alzheimer’s continuum
A+T-(N)+: Alzheimer’s with suspected non Alzheimer’s pathologic change; Alzheimer’s continuum
A-T+(N)-: Non-AD pathologic change
A-T-(N)+: Non-AD pathologic change
A-T+(N)+: Non-AD pathologic change

“This latter biomarker profile implies evidence of one or more neuropathologic processes other than AD and has been labeled ‘suspected non-Alzheimer’s pathophysiology, or SNAP,” according to the paper.

Cognitive staging further refines each person’s status. There are two clinical staging schemes in the framework. One is the familiar syndromal staging system of cognitively unimpaired, MCI, and dementia, which can be subdivided into mild, moderate, and severe. This can be applied to anyone with a biomarker profile.

“This three-category division serves as the basis for cognitive categorization in many large ongoing studies,” Dr. Jack and his colleagues wrote. “Numerous researchers feel that it has been and continues to be effective for clinical research and that abandoning it would unnecessarily disrupt ongoing studies.”