Dementia testing

AD-Detect^TM ABeta 42/40 and p-tau217 Evaluation

This panel combines Aβ 42/40 and p-tau217 plasma levels to help establish the likelihood of amyloid pathology consistent with Alzheimer's disease, evaluated at 91% sensitivity and 91% specificity—meeting accepted performance standards for blood-based biomarker tests.^2,3

The biomarker values are combined into a single analytical interpretation, which has been shown to significantly improve predictive performance and accuracy for detecting amyloid positivity corresponding to the findings of an amyloid PET scan and establishing a diagnosis of Alzheimer's disease.

Quest AD-Detect^® Beta-Amyloid 42/40 Ratio

This test assesses beta-amyloid 42/40 (Aβ42/40) ratio via plasma. This ratio measures levels of 2 beta-amyloid peptides, where certain ratio results may suggest a risk of developing Alzheimer’s disease.⁴ Blood-based amyloid testing provides an accessible, affordable tool as part of Alzheimer’s disease risk assessment and ongoing monitoring, aiding in evaluation of further comprehensive testing needs.

Quest AD-Detect^® p-tau217

Plasma testing for the phosphorylated tau217 (p-tau217) biomarker can help assess whether mild cognitive impairment (MCI) or dementia is caused by Alzheimer’s disease.^5-7

Current research indicates that plasma p-tau—including p-tau217—is concordant with amyloid status defined by either cerebrospinal fluid (CSF) biomarker testing or positron emission tomography (PET) scan analysis and has been shown to predict progression to Alzheimer’s disease.^5-9 It can differentiate between Alzheimer’s disease and non-Alzhiemer's disease neurodegenerative conditions and identify patients who may benefit from further diagnostic testing.^5-7

Quest AD-Detect^® p-tau181

This test is used to detect phosphorylated tau (p-tau181) proteins, one of the hallmark biomarkers involved in the diagnosis and staging of Alzheimer’s disease. P-tau181 concentrations increase over time within plasma as Alzheimer’s disease progresses.^10,11 Routine monitoring of p-tau181 levels via plasma is ideal to support care pathways as it is less invasive, less expensive, and more practical than other methods. Combined plasma p-tau and Aβ42/40 biomarker testing has been shown to help identify patients at risk of experiencing faster cognitive decline¹² and which patients can benefit from further diagnostic testing.

Quest AD-Detect^® Apolipoprotein (ApoE) Isoform

It’s critical to understand ApoE status for patients considering amyloid-modifying therapies. This test can provide insights on the presence of ApoE isoforms, a well-known biomarker associated with risk of developing Alzheimer’s disease.⁴ Insights into a patient’s ApoE status can help assess the risk of amyloid-related imaging abnormalities (ARIA) in patients considering amyloid-modifying therapeutics. Quest (data on file) and others^13,14 have shown that the results of phenotyping are 100% concordant with ApoE genotyping results.

Blood-based test to assess neuronal damage from neurodegenerative diseases, such as Alzheimer’s disease and multiple sclerosis (MS), and traumatic brain injury (TBI) like that caused by concussions.

Neurofilament light chain (NfL) is a neuron-specific protein routinely released into the extracellular space of the brain. Serum NfL levels rise above baseline in response to neuronal injury and neurodegeneration.

This test combines ApoE results with Aβ42/40 ratio into an algorithm to assess Alzheimer’s disease risk, and can help assess the risk of amyloid related imaging abnormalities (ARIA) in patients considering amyloid-modifying therapeutics.

This test combines 3 biomarkers, phospho-tau, total tau, and Aβ42, to help you provide clinically relevant information regarding Alzheimer’s disease staging that may help guide patient management.

This test can provide insights into a patient’s ApoE status. ApoE is a key biomarker associated with an increased risk of developing Alzheimer’s disease.¹⁵