Date of Award


Document Type

Scholarly Project

Degree Name

Master of Physician Assistant Studies (MPAS)


Physician Assistant Studies

First Advisor

Jay Metzger


Alzheimer’s Disease; Amyloid beta; Tau; PET; Cerebral spinal fluid; Blood; APOE-ε4


Alzheimer’s Disease (AD) is a progressive form of dementia that affects memory, cognition, and functional ability. Although there are diagnostic tests being used to aid in the clinical diagnosis of AD, the only definitive method of diagnosis is through post-mortem biopsy of the brain. The purpose of this project and literature review is to investigate the most effective biomarkers when clinically evaluating AD. The main biomarkers of investigation include positron emission tomography (PET) imaging, cerebral spinal fluid (CSF), and blood-based biomarkers. The role of the apolipoprotein E (APOE4) gene as a genetic influence on AD was also evaluated within this literature review. Studies regarding information on CSF and plasma biomarkers that were dated prior to 2016 were excluded. Studies regarding PET imaging dated prior to 2011 were also excluded. The research conducted in this review indicates that an individual with a positive APOE4 genotype has a higher risk of developing AD in comparison to those with APOE2 and APOE3 genotypes. Amyloid PET imaging and CSF biomarkers demonstrate immense potential in offering diagnostic hope of AD. Of the CSF biomarkers, the Ab-1-42/T-tau and Ab-1-42/Ptau181 ratios may be the most reliable in recognizing AD. Plasma biomarkers Ab 42/40 and plasma p-tau 181 have shown extreme promise in presumed AD cases. The PrecivityADTM blood test is the first available blood test used to identify AD pathology, by use of plasma Ab 42/40 and APOE genotype.