Uncovering cerebral blood flow patterns corresponding to Amyloid-beta accumulations in patients across the Alzheimer's disease continuum using the arterial spin labeling

Abstract

BackgroundAlzheimer's disease (AD) is a progressive neurodegenerative disorder ranging from mild cognitive impairment (MCI) to AD dementia. Abnormal cerebral perfusion alterations, influenced by amyloid-beta (A beta) accumulations, have been implicated in cognitive decline along this spectrum.ObjectiveThis study investigates the relationship between cerebrospinal fluid (CSF) A beta 1-42 levels and regional cerebral blood flow (CBF) changes across the AD continuum using the Arterial Spin Labeling (ASL) technique.MethodsWe analyzed data from 229 participants extracted from the ADNI cohort, comprising of 50 cognitively normal (CN), 13 subjective memory complaints (SMC), 83 early MCI (EMCI), 52 late MCI (LMCI), and 31 AD participants with complete ASL and CSF data. Correlations between A beta 1-42 levels and regional mean CBF values were assessed. Multiple linear regression models accounted for confounders, including age, gender, and education level.ResultsPreliminary unadjusted analyses revealed strong positive correlations between A beta 1-42 levels and CBF in multiple regions, predominantly in the AD group. After adjusting for confounders, significant correlations in AD participants emerged in the left pars triangularis and left caudal middle frontal cortex. In the LMCI group, significant associations were identified in the right lateral occipital cortex, right inferior parietal cortex, and left amygdala.ConclusionThese findings highlight the critical role of A beta-driven CBF alterations in regions associated with higher cognitive functions and suggest that these patterns may serve as potential biomarkers for diagnosing and monitoring disease progression.