An Overview of New and Emerging Technologies for Early Diagnosis of Alzheimer Disease

Abstract

Alzheimer disease is a progressive neurologic condition that leads to the decline of cognitive functioning and eventual death. There is currently no cure. Proposed causes of Alzheimer disease include the amyloid hypothesis, which suggests that it is caused by a buildup of amyloid-beta and tau proteins in the brain, leading to cell death. Recent diagnostic tools focus on amyloid and tau proteins as potential markers of the disease, and new treatments are also focusing on amyloid and tau formation. Earlier diagnosis of Alzheimer disease allows time for planning for care and support needs before symptoms worsen. It also allows for both drug and non-drug treatments to be used earlier, which may prolong time with a higher quality of life. Emerging diagnostic tools include biomarker-based tools, such as MRI, PET, CT, blood-based biomarkers, cerebrospinal fluid-based biomarkers, ocular testing, and salivary biomarkers. The majority of these tools are in the research phase, although imaging is often used in combination with cognitive testing to diagnose Alzheimer disease. One blood-based biomarker test is available in the US (paid out of pocket). It is unclear whether testing will be available in Canada or when this will happen.