Structural network efficiency mediates the association between glymphatic function and cognition in mild VCI: a...

Area of Science:

• Neuroscience
• Radiology
• Gerontology

Background:

• Vascular cognitive impairment (VCI) presents as a network disconnection disorder with heterogeneous causes.
• Glymphatic system dysfunction is increasingly recognized as a common pathway in dementia.
• Diffusion Tensor Image Analysis Along the Perivascular Space (DTI-ALPS) enables non-invasive assessment of glymphatic function.

Purpose of the Study:

• To investigate glymphatic function alterations in VCI patients.
• To explore the impact of glymphatic dysfunction on brain network connectivity in VCI.
• To identify potential common pathological mechanisms in VCI subtypes.

Main Methods:

• Recruited 79 VCI patients (40 SVCI, 39 PSCI) and 77 normal cognitive (NC) controls.
• Conducted neuropsychological assessments and multimodal MRI scans.
• Calculated ALPS-index, constructed structural networks via tractography, and evaluated network topological metrics.

Main Results:

• VCI patients exhibited significantly lower ALPS-index compared to NC subjects.
• ALPS-index independently affected cognitive function and correlated with vascular risk factors and pathologies.
• Global network efficiency (Eg) correlated with ALPS-index in SVCI and PSCI patients, partially mediating the effect of glymphatic dysfunction on cognitive impairment.

Conclusions:

• Decreased ALPS-index in VCI subtypes indicates impaired glymphatic function.
• Glymphatic dysfunction may contribute to VCI by disrupting network connectivity.
• ALPS-index shows promise as an emerging imaging biomarker for VCI.