Linking Cognitive Variability and Alzheimers Disease Biomarkers by Neurocognitive Status.

Area of Science:

• Neuroscience
• Gerontology
• Biomarker Research

Background:

• Alzheimer's Disease (AD) is a progressive neurodegenerative disorder.
• Cognitive variability is a potential indicator of neurological changes.
• Understanding factors influencing cognitive variability is crucial for early AD detection.

Purpose of the Study:

• To investigate the relationship between Alzheimer's Disease (AD) biomarkers and intra-individual cognitive variability (IICV).
• To assess if IICV can serve as a sensitive outcome measure in the clinical phase of AD.

Main Methods:

• Utilized data from 879 adults (≥50 years) from the National Alzheimer's Coordinating Center.
• Employed moderated regression models to analyze the impact of AD biomarkers (CSF Aβ42, p-Tau181, t-Tau; amyloid PET) and neurocognitive status on IICV (iSD, CoV).
• Controlled for demographic factors in the analyses.

Main Results:

• Increased AD biomarker burden correlated with higher IICV in cognitively impaired individuals.
• No significant association between AD biomarkers and IICV was found in cognitively intact individuals.
• The strength of association between AD biomarkers and IICV was comparable to their association with mean cognitive performance.

Conclusions:

• Elevated levels of amyloid, tau, and neurodegeneration markers are linked to increased IICV in cognitively impaired older adults.
• IICV shows potential as a sensitive outcome measure for monitoring AD progression.
• Further longitudinal studies in diverse populations are recommended to validate these findings.