Cognitive decline due to aging among persons with Down syndrome

Area of Science:

• Neuroscience
• Developmental Psychology
• Gerontology

Background:

• Down syndrome (DS) is associated with an increased risk of early-onset Alzheimer's disease.
• Cognitive aging in individuals with DS requires further investigation, particularly in comparison to non-DS individuals with intellectual disabilities.
• Understanding cognitive trajectories is crucial for early intervention and support.

Purpose of the Study:

• To compare cognitive function decline in older adults with Down syndrome (DS) versus those without DS (NonDS).
• To identify specific cognitive domains most affected by aging in the DS population.
• To explore the potential of cognitive tests as early indicators for Alzheimer's disease in DS.

Main Methods:

• Comparative study design involving two groups: DS (n=32) and NonDS (n=31).
• Participants were categorized into younger (40-49 years) and older (50-62 years) age groups.
• Cognitive functions assessed using the Dementia Rating Scale, Peabody Picture Vocabulary Test-Revised, Matrix Analogies Test-Expanded, and Das-Naglieri Cognitive Assessment System.

Main Results:

• Older individuals with Down syndrome exhibited poorer performance on cognitive tests compared to younger DS, older NonDS, and younger NonDS groups.
• Planning and attention processing were the most significantly affected cognitive domains in the older DS group.
• Age-related cognitive decline was more pronounced in individuals with Down syndrome.

Conclusions:

• Cognitive decline, particularly in planning and attention, is evident in older adults with Down syndrome.
• The observed cognitive deficits may serve as potential early biomarkers for Alzheimer's disease in the DS population.
• Further research is warranted to validate these cognitive tests for early Alzheimer's detection in DS.