Early dementia diagnosis: blood proteins reveal at-risk people The results of a large-scale screening study could be used to develop blood tests to diagnose diseases such as Alzheimer’s before symptoms take hold.
M Naddaf, Nature, February 13, 2024
From the article: "An analysis of around 1,500 blood proteins has identified biomarkers that can be used to predict the risk of developing dementia up to 15 years before diagnosis. The findings are a step towards a tool that scientists have been in search of for decades: blood tests that can detect Alzheimer’s disease and other forms of dementia at a very early, pre-symptomatic stage. Researchers screened blood samples from more than 50,000 healthy adults in the UK Biobank, 1,417 of whom developed dementia in a 14-year period."
They found that high blood levels of four proteins — GFAP, NEFL, GDF15 and LTBP2 — were strongly associated with dementia. "
Assessment of Mendelian and risk factor genes in Alzheimer disease: a prospective nationwide clinical utility study and recommendations for genetic screening
G Nicolas et al, Genetics in Med, January 24, 2024
From the abstract: "We included 700 patients in a prospective study and performed exome sequencing. A panel of 28 Mendelian and 6 risk-factor genes was interpreted and returned to patients. We built a framework for risk variant interpretation and risk gradation and assessed the detection rates among early-onset AD (EOAD, age of onset (AOO) =65 years, n=608) depending on AOO and pedigree structure and late-onset AD (LOAD, 66<AOO<75, n=92).Twenty-one patients carried a LP/P variant in a Mendelian gene (all with EOAD, 3.4%), 20/21 affected APP, PSEN1 or PSEN2. LP/P variant detection rates in EOAD ranged from 1.7% to 11.6% based on AOO and pedigree structure. "
Direct to Consumer Biomarker Testing for Alzheimer Disease—Are We Ready for the Insurance Consequences?
JJ Arias et al, JAMA Neurology, December 18, 2023
From the article: "The promise of DTC testing for AD biomarkers may be lauded by advocates pushing for earlier diagnoses and individuals’ right to know. Early diagnosis of AD through DTC or clinical evaluations could provide benefits, including increased monitoring and preventive care. Additionally, DTC tests could reduce barriers that impede a timely diagnosis (eg, access to dementia specialists). However, DTC tests are not without hazard, particularly given gaps in discriminatory protections for individuals at risk of developing AD with known biomarker status. "
Attitudes toward pre-symptomatic screening for Alzheimer’s dementia in five European countries: a comparison of family members of people with Alzheimer’s dementia versus non-family members
IA Angelidou et al, Frontiers Genetics, December 2023
From the abstract: " Pre-symptomatic screening is getting more attention in healthcare as it detects the risk for developing neurodegenerative diseases like Alzheimer’s disease (AD), which is very useful for treatment or prevention. AD screening could play an important role in individuals with at least one affected first-degree relative, but also without family history. As the demand for screening is rising worldwide, it is important to consider possible cross-cultural differences in attitudes toward pre-symptomatic screening."