Pattern of regional white matter hyperintensity volume in mild cognitive impairment subtypes and associations with...

Area of Science:

• Neurology
• Neuroimaging
• Cognitive Science

Background:

• White matter hyperintensities (WMHs) are indicators of small-vessel cerebrovascular disease and are associated with an increased risk of mild cognitive impairment (MCI).
• The specific distribution of WMHs across different brain regions and their association with MCI subtypes and functional decline remain less understood.

Purpose of the Study:

• To investigate whether regional WMHs differentiate between amnestic MCI (aMCI) and nonamnestic MCI (naMCI) subtypes.
• To determine if regional WMHs predict the decline in everyday functioning in individuals with MCI.

Main Methods:

• The study analyzed data from 618 participants in the Alzheimer's Disease Neuroimaging Initiative, including cognitively normal (CN), aMCI, and naMCI groups.
• Participants underwent neuropsychological testing, MRI scans to assess WMHs, and evaluations of everyday functioning.

Main Results:

• Participants with aMCI showed increased temporal and occipital WMHs compared to CN individuals.
• naMCI participants exhibited greater WMHs in frontal, temporal, parietal, and occipital regions compared to CN, and more occipital WMHs than aMCI participants.
• Increased WMHs in temporal and occipital regions were associated with faster decline in everyday functioning, with temporal lobe WMHs disproportionately affecting naMCI patients.

Conclusions:

• Regional variations in WMH volumes are observed across different cognitive groups (CN, aMCI, naMCI).
• WMHs, particularly in temporal and occipital regions, serve as predictors of functional decline.
• Cerebrovascular markers like WMHs may aid in identifying individuals at risk for cognitive decline and distinguishing between MCI subtypes.