Amyloid-PET and White Matter Hyperintensities Have Independent Effects on Baseline Cognitive Function and Synergistic Effects on Longitudinal Executive Function.
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ABSTRACT:
SUBMITTER: Ali DG
PROVIDER: S-EPMC9953773 | biostudies-literature | 2023 Jan
REPOSITORIES: biostudies-literature
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Amyloid-PET and White Matter Hyperintensities Have Independent Effects on Baseline Cognitive Function and Synergistic Effects on Longitudinal Executive Function.
Ali Doaa G DG Abner Erin L EL Bahrani Ahmed A AA El Khouli Riham R Gold Brian T BT Jiang Yang Y Wilcock Donna M DM Jicha Gregory A GA
Brain sciences 20230128 2
Co-occurrence of beta amyloid (Aβ) and white matter hyperintensities (WMHs) increase the risk of dementia and both are considered biomarkers of preclinical dementia. Moderation and mediation modeling were used to define the interplay between global and regional Aβ and WMHs measures in relation to executive function (EF) and memory composite scores outcomes at baseline and after approximately 2 years across a sample of 714 clinically normal participants from the Alzheimer's Disease Neuroimaging I ...[more]
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Project description:IntroductionCognitive decline in Alzheimer's disease is associated with amyloid beta (Aβ) accumulation, neurodegeneration, and cerebral small vessel disease, but the temporal relationships among these factors is not well established.MethodsData included white matter hyperintensity (WMH) load, gray matter (GM) atrophy and Alzheimer's Disease Assessment Scale-Cognitive-Plus (ADAS13) scores for 720 participants and cerebrospinal fluid amyloid (Aβ1-42) for 461 participants from the Alzheimer's Disease Neuroimaging Initiative. Linear regressions were used to assess the relationships among baseline WMH, GM, and Aβ1-42 to changes in WMH, GM, Aβ1-42, and cognition at 1-year follow-up.ResultsBaseline WMHs and Aβ1-42 predicted WMH increase and GM atrophy. Baseline WMHs and Aβ1-42 predicted worsening cognition. Only baseline Aβ1-42 predicted change in Aβ1-42.DiscussionBaseline WMHs lead to greater future GM atrophy and cognitive decline, suggesting that WM damage precedes neurodegeneration and cognitive decline. Baseline Aβ1-42 predicted WMH increase, suggesting a potential role of amyloid in WM damage.
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