Prefrontal-Parietal White Matter Volumes in Healthy Elderlies Are Decreased in Proportion to the Degree of...

Area of Science:

• Neuroscience
• Gerontology
• Cardiology

Background:

• Cardiovascular risk (CVR) factors are increasingly recognized as potential contributors to cognitive decline and structural brain changes in aging populations.
• Previous research suggests a link between CVR and cognitive functioning, but detailed neuroanatomical correlates, particularly in white matter (WM), require further investigation.

Purpose of the Study:

• To investigate the association between cardiovascular risk (CVR) levels and regional white matter (WM) brain volumes in older adults.
• To explore the relationship between CVR-related WM deficits and cognitive performance, specifically inhibitory control.

Main Methods:

• Utilized magnetic resonance imaging (MRI) and voxel-based morphometry (VBM) to assess regional WM volumes in a population-based sample of 156 individuals aged 65-75 years.
• Participants were stratified into low, intermediate, and high CVR subgroups based on the Framingham Risk Score.
• Cognitive function was evaluated using the Short Cognitive Performance Test.

Main Results:

• Individuals in the high CVR subgroup exhibited significantly reduced WM volume in the right juxtacortical dorsolateral prefrontal region compared to low and intermediate CVR groups.
• These prefrontal WM volume reductions remained significant even after controlling for APOEε4 allele presence.
• A negative correlation was observed between inhibitory control performance and right prefrontal WM volume, which was proportional to the degree of CVR.
• The high CVR group also showed significantly reduced bilateral deep parietal WM volume.

Conclusions:

• This study provides the first large-scale documentation of the specific topography of WM brain volume deficits associated with cardiovascular risk.
• The identified prefrontal WM deficits in high-risk individuals are clinically relevant, as they correlate with impaired inhibitory control, a function dependent on prefrontal integrity.