Decoding brain structure to stage Alzheimer's disease pathology in Down syndrome

Area of Science:

• Neuroimaging
• Alzheimer's Disease Research
• Down Syndrome Studies

Background:

• Alzheimer's disease (AD) in Down syndrome (DS) involves brain structural changes.
• Current understanding of how these changes correlate with AD stages and compare to other genetic AD forms is limited.

Purpose of the Study:

• To determine if cortical thickness and volumetric changes can identify AD stages in DS.
• To compare these brain changes in DS with those in autosomal-dominant AD (ADAD).

Main Methods:

• 178 DS adults underwent MRI scans, categorized as nonclinical, preclinical, or symptomatic.
• Cortical thickness and subcortical volumes were analyzed and compared across DS groups.
• Receiver operating characteristic analyses evaluated their efficacy as staging metrics.

Main Results:

• Reduced parietal and temporal lobe thickness significantly differentiated amyloid positivity and cognitive impairment in DS.
• Cortical thickness metrics showed better discriminative ability than subcortical volumes.
• AD in DS exhibited more widespread and severe thickness differences compared to ADAD.

Conclusions:

• Cortical thickness serves as a reliable biomarker for staging AD pathology in individuals with DS.
• Identifying affected brain regions aids in monitoring disease progression and assessing therapeutic interventions for DSAD.