Brain amyloid and vascular risk are related to distinct white matter hyperintensity patterns

Area of Science:

• Neurology
• Neuroimaging
• Alzheimer's Disease Research

Background:

• White matter hyperintensities (WMHs) are common neuroimaging findings.
• WMHs are associated with vascular risk factors and Alzheimer's disease (AD).
• Understanding WMH distribution and its relation to AD pathology and vascular risk is crucial for early diagnosis.

Purpose of the Study:

• To investigate the relationship between white matter hyperintensity (WMH) load and distribution.
• To examine associations with amyloid-beta (Aβ) pathology and cardiovascular disease risk.
• To determine if regional WMH patterns differ in individuals with subjective cognitive decline (SCD) or mild cognitive impairment (MCI) based on Aβ status.

Main Methods:

• Utilized an automated algorithm to quantify regional deep (DWMH) and periventricular (PWMH) WMH loads in 339 participants.
• Stratified participants based on amyloid-beta (Aβ) pathology (Aβ+/-).
• Analyzed group differences and associations with Framingham Risk Score for cardiovascular disease (FRS-CVD) and age.

Main Results:

• Increased occipital PWMH and DWMH loads were observed in SCD with Aβ+ compared to controls without Aβ.
• MCI with Aβ+ showed differences in global WMH, occipital DWMH, and temporal DWMH loads compared to MCI without Aβ.
• Frontal PWMHs and DWMHs were associated with FRS-CVD, independent of age.
• Global and regional WMH loads were associated with age.

Conclusions:

• Posterior WMH loads are elevated in individuals with early cognitive decline and positive amyloid pathology.
• Frontal WMH distribution is linked to cardiovascular risk factors.
• Regional WMH topography may serve as an early indicator of disease etiology in cognitive impairment.