Publications by authors named "C M Laymon"
Background: The relationship between subtle cognitive decline and Alzheimer's disease (AD) pathology as measured by biomarkers in settings outside of specialty memory clinics is not well characterized.
Objective: To investigate how subtle longitudinal cognitive decline relates to neuroimaging biomarkers in individuals drawn from a population-based study in an economically depressed, small-town area in southwestern Pennsylvania, USA.
Methods: A subset of participants without dementia (N = 115, age 76.
Introduction: Adults with Down syndrome demonstrate striatum-first amyloid accumulation with [C]PiB PET imaging, which has not been replicated with [F]florbetapir (FBP). Early striatal accumulation has not been temporally quantified with respect to global cortical measures.
Methods: Longitudinal PiB (n=175 participants) and FBP (n=92 participants) data from the Alzheimer Biomarkers Consortium-Down Syndrome were used to measure cortical and striatal binding.
Article Synopsis
- This study focused on the risk of Alzheimer's disease in adults with Down syndrome, using amyloid and tau PET imaging to track disease progression.
- It involved a longitudinal analysis of 167 participants, assessing cognitive functioning and biomarkers over two visits between 2017 and 2022.
- The research aimed to determine the timeline for symptomatic Alzheimer's based on "amyloid age" and its relation to cognitive decline and tau accumulation.
Article Synopsis
- - Individuals with Down syndrome (DS) face a high risk of developing Alzheimer's disease (AD), but about 20% do not show dementia symptoms until later in life, potentially due to the presence of mosaicism, which can reduce gene expression from chromosome 21.
- - Researchers analyzed data from two major studies (ABC-DS and a legacy study) that included neuropsychological assessments and biomarkers to determine the prevalence and impact of mosaicism, finding it in less than 10% of participants.
- - Those with mosaicism exhibited lower levels of AD-related biomarkers and a slower decline in cognitive scores compared to individuals with full trisomy, indicating a potential protective effect against dementia, though more research is needed to fully understand these findings.
Article Synopsis
- The study investigates the relationship between amyloid-beta (Aβ) and tau biomarkers and the onset of symptomatic Alzheimer's disease (AD) in adults with Down syndrome (DS), highlighting the concept of "amyloid age."* -
- It analyzes data from 167 adults with DS over roughly five years, finding that cognitive decline becomes noticeable about 2.7 years after reaching Aβ+ status, with tau levels also increasing subsequently.* -
- The findings suggest a quicker progression to cognitive impairment and dementia in individuals with DS compared to typical late-onset AD, emphasizing the relevance of amyloid age for clinical practice and research.*