Sex-specific differences in white matter microvascular integrity after ischaemic stroke

Area of Science:

• Neuroscience
• Vascular Neurology
• Medical Imaging

Background:

• Functional outcomes after ischemic stroke are worse in women.
• White matter microvascular integrity is a risk factor for poor functional outcomes.
• Sex-specific differences in microvascular integrity after stroke are not well understood.

Purpose of the Study:

• To characterize sex-specific differences in white matter microvascular integrity in acute ischemic stroke patients.
• To investigate the relationship between microvascular integrity and stroke outcomes.

Main Methods:

• Retrospective analysis of acute ischemic stroke patients with brain MRI (DWI and DSC).
• Measurement of normal-appearing white matter (NAWM) K2 coefficient and apparent diffusion coefficient (ADC) in the hemisphere contralateral to the infarct.
• Regression analyses to identify predictors of K2 coefficient, DWI volume, and good functional outcome (90-day mRS < 2).

Main Results:

• 79 women and 105 men were analyzed; no age difference was observed.
• Women exhibited a significantly higher NAWM K2 coefficient compared to men (1027.4 vs 692.7×10^-6/s; p=0.006).
• In women, atrial fibrillation and higher NAWM ADC were associated with increased K2 coefficient. K2 coefficient independently predicted DWI volume in women, but not men.

Conclusions:

• Increased NAWM K2 coefficient in women with acute ischemic stroke is linked to larger infarct volumes and poorer white matter integrity.
• Findings suggest sex-specific differences in white matter microvascular integrity after ischemic stroke.
• Further prospective studies are warranted to explore these sex-specific differences.