Periventricular hyperintensities are associated with elevated cerebral amyloid.

Area of Science:

• Neuroimaging
• Neuropathology
• Alzheimer's Disease Research

Background:

• Periventricular white matter hyperintensities (PVWMH) are common in aging brains.
• Cerebral β-amyloid (Aβ) deposition is a hallmark of Alzheimer's disease (AD).
• Understanding the relationship between PVWMH and Aβ is crucial for AD pathogenesis.

Purpose of the Study:

• To investigate the association between PVWMH and biomarkers of elevated cerebral β-amyloid (Aβ).
• To examine this relationship within the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort.
• To determine if the association is independent of known confounders.

Main Methods:

• Utilized 3T fluid-attenuated inversion recovery MRI to assess PVWMH burden in 698 participants (cognitively normal and mild cognitive impairment).
• Employed a novel semiquantitative visual rating scale for frontal, parietal, and occipital PVWMH.
• Correlated PVWMH with cerebrospinal fluid (CSF)-Aβ, florbetapir-PET, and fluorodeoxyglucose (FDG)-PET biomarkers.

Main Results:

• Increased PVWMH burden in frontal, parietal, and occipital regions correlated with elevated cerebral amyloid (high florbetapir-PET, low CSF-Aβ).
• PVWMH remained independently associated with high florbetapir-PET uptake and CSF-Aβ after adjusting for age, sex, APOE status, and vascular factors.
• PVWMH were also associated with cerebral hypometabolism (FDG-PET) and weaker associations with CSF-tau and CSF-phospho-tau.

Conclusions:

• Elevated PVWMH are significantly associated with increased cerebral amyloid burden.
• This association is independent of key confounders including age, APOE genotype, and vascular risk factors.
• Further research is needed to elucidate the underlying mechanisms connecting PVWMH and cerebral amyloid accumulation.