Peripheral Biomarkers for Alzheimer’s Disease: Update and Progress

Excerpt

In 1984, the NINDS-ADRDA published criteria stating that definite Alzheimer’s disease (AD) could only be confirmed by biopsy or autopsy [1]. This publication led to the widely held perception that AD diagnosis was a diagnosis of exclusion only. Since then, the field has evolved rapidly with the advent of cerebrospinal fluid (CSF) testing for AD with great sensitivity and specificity [2], and the development of amyloid positron emission tomography (PET), tau PET, and fluorodeoxyglucose PET. Amyloid PET has emerged as an added value test that could alter clinical management [3, 4]. Magnetic resonance imaging (MRI) is also evolving as a tool to measure regional volumes, particularly within the hippocampus, as a proxy measure of neurodegeneration. Many of these tests have excellent specificity and sensitivity but are limited by access/availability of such technologies as PET, the expense of tests, and the invasive quality of lumbar puncture. …