Alzheimer's Imaging Consortium

Area of Science:

• Neuroimaging
• Alzheimer's Disease Research
• Cognitive Neuroscience

Background:

• Brain and cognitive resilience (BR, CR) are key to maintaining function despite Alzheimer's disease (AD) tau pathology.
• Tau pathology can be measured by spatial extent (SEOT) or load (SUVR).
• Understanding factors influencing BR and CR is crucial for AD management.

Purpose of the Study:

• Compare SEOT and SUVR in their association with BR and CR.
• Replicate previous findings using MK-6240 PET imaging.
• Evaluate demographic, genetic, and imaging factors linked to BR and CR.

Main Methods:

• 126 amyloid-β-positive participants from the TRIAD cohort underwent tau-PET ([18F]MK6240) and cognitive assessments (MMSE).
• SEOT was quantified as the proportion of voxels with abnormal tau deposition relative to young controls.
• Participants included individuals with mild cognitive impairment (MCI) or AD.

Main Results:

• Higher Whole Cortex MK SUVR correlated with lower MMSE scores, indicating tau pathology is linked to cognitive decline.
• MCI patients showed higher MMSE scores despite some tau accumulation compared to AD patients.
• Whole Cortex SEOT demonstrated a stronger negative correlation with MMSE than SUVR, suggesting SEOT is more sensitive to cognitive decline.

Conclusions:

• Whole Cortex SEOT is a more sensitive marker of cognitive decline in AD and MCI than Whole Cortex MK-6240 SUVR.
• SEOT shows a stronger association with cognitive impairment progression.
• Further research is warranted to validate SEOT as a biomarker for neurodegenerative conditions.