Impact of Peripheral Microvascular Endothelial Dysfunction on White Matter Hyperintensity

Area of Science:

• Neurology
• Vascular Medicine
• Radiology

Background:

• White matter hyperintensity (WMH) on MRI is associated with increased ischemic stroke (IS) risk.
• Endothelial dysfunction serves as a key indicator of vascular health and a predictor of IS.
• Understanding the relationship between endothelial function and WMH is crucial for IS risk assessment.

Purpose of the Study:

• To investigate the association between peripheral endothelial dysfunction and regional WMH.
• To determine the impact of this association on the future risk of ischemic stroke (IS).
• To explore age-related differences in WMH and endothelial function.

Main Methods:

• 219 patients without prior IS underwent assessment of endothelial function via reactive hyperemia peripheral arterial tonometry.
• Brain MRI was used for volumetric WMH segmentation with an automated digital tool.
• Patients were categorized by age (≤50 years vs. >50 years) and followed for IS risk.

Main Results:

• WMH volume, particularly juxtacortical WMH, increased with age, being more pronounced in patients over 50.
• In patients >50 years, poorer endothelial function (lower reactive hyperemia index) correlated with higher total and juxtacortical WMH volumes.
• Higher juxtacortical WMH volume was significantly associated with an increased risk of IS over a median 6.5-year follow-up.

Conclusions:

• Peripheral endothelial dysfunction is linked to increased juxtacortical WMH in older adults (>50 years).
• Juxtacortical WMH volume in this population may serve as a valuable biomarker for predicting future ischemic stroke risk.
• This study highlights the importance of assessing endothelial function in managing cerebrovascular health.