White Matter Hyperintensities Related to Parkinson's Disease Executive Function

Area of Science:

• Neuroscience
• Neurology
• Radiology

Background:

• Parkinson's disease (PD) is associated with multidomain cognitive impairments.
• The specific pathologies driving domain-specific cognitive dysfunction in PD remain unclear.

Purpose of the Study:

• To investigate the contribution of vascular copathology, specifically white matter hyperintensities (WMH) severity and location via MRI, to domain-specific cognitive impairment in Parkinson's disease.

Main Methods:

• Studied 85 PD patients and 18 controls, assessing WMH severity using the Fazekas scale.
• Classified PD patients into PD with WMH (PD+WMH) and without WMH (PD-WMH) groups.
• Conducted cognitive testing (global, executive, visuospatial, memory, language) and generated WMH probability maps.

Main Results:

• The PD+WMH group exhibited poorer global and executive cognitive performance compared to the PD-WMH group.
• Specific cognitive deficits in PD+WMH included lower scores on MoCA, Stroop, SDMT, and Digit Span.
• WMH probability maps indicated lesion locations associated with specific cognitive deficits, such as the corticospinal tract for executive functions.

Conclusions:

• WMH severity correlates with executive dysfunction in PD, affecting attention, working memory, and processing speed.
• Disruption of white matter tracts near vascular lesions likely contributes to these cognitive impairments.
• Early vascular disease management may alleviate executive dysfunction in a subset of PD patients.