Abstract
In the last few years, an improved understanding of dementia biomarkers has significantly
increased the diagnostic accuracy for dementias. The National Institutes of Health
Biomarkers Definitions Working Group defines a biomarker as “a characteristic that
is objectively measured and evaluated as an indicator of normal biological processes,
pathogenic processes, or pharmacologic responses to a therapeutic intervention.” In
the field of dementia, a biomarker is a biological measure pointing to a specific
dementing pathology. Dementia biomarkers may also serve as surrogates for disease
progression and as endpoints in clinical trials. Dementia biomarkers are best characterized
for Alzheimer's disease, which is the most common form of primary dementia. The current
“biological” conception of Alzheimer's disease is based on consideration of three
biomarkers: amyloid, tau, and “neurodegeneration.” The status of these biomarkers
may be determined by cerebrospinal fluid clinical chemistry or imaging. Biomarkers
for other primary dementias are less reliable and rely chiefly on structural and functional
imaging. When appropriate, genetic testing may help with diagnostic certainty in hereditary
forms of dementia.
Keywords
dementia biomarkers - amyloid protein - tau protein - neurodegeneration - FDG-PET
