White-matter changes in early and late stages of mild cognitive impairment

Area of Science:

• Neuroscience
• Gerontology
• Radiology

Background:

• Mild Cognitive Impairment (MCI) involves cognitive deficits beyond normal aging, with a high risk of progressing to Alzheimer's Disease (AD).
• Early identification of brain changes in MCI is crucial for understanding dementia progression.
• White-matter changes are increasingly recognized as significant factors in cognitive decline.

Purpose of the Study:

• To investigate the relationship between white-matter changes and structural brain alterations in MCI patients.
• To determine if white-matter changes correlate with cognitive performance in early and late MCI.
• To explore the specific impact of white-matter hyperintensities (WMHs) on cognitive function in MCI.

Main Methods:

• Forty-nine MCI patients were categorized into Early MCI (E-MCI) and Late MCI (L-MCI) based on FCSRT performance.
• White-matter changes were assessed using the Age-Related White-Matter Changes (ARWMC) scale.
• Brain region volumes, including hippocampus and white matter, were quantified using FreeSurfer; group and correlation analyses were performed.

Main Results:

• Late MCI patients exhibited significantly more white-matter hyperintensities (WMHs) in frontal regions compared to E-MCI patients.
• No significant correlation was found between ARWMC scores and total hippocampal or white-matter volumes.
• Frontal white-matter changes were specifically associated with cognitive performance in MCI patients.

Conclusions:

• White-matter hyperintensities (WMHs) play a critical role in the pathophysiology of Mild Cognitive Impairment (MCI).
• Cognitive functions in MCI patients are demonstrably affected by white-matter alterations, particularly in the frontal lobes.
• These findings underscore the importance of evaluating white-matter integrity for understanding and potentially intervening in MCI progression.