Asymmetrical patterns of β-amyloid deposition and cognitive changes in Alzheimer's disease: the SILCODE study

The asymmetric pattern of β-amyloid plaque distribution across Alzheimer's disease clinical progression stages remains unclear. In this study, 66 participants with normal cognition, 59 with subjective cognitive decline, 12 with mild cognitive impairment, and 11 with Alzheimer's disease dementia were included in the Sino Longitudinal Study on Cognitive Decline (SILCODE) cohort. A regional asymmetry index, denoting the left-right asymmetry of β-amyloid plaques, was derived for each region based on the Anatomical Automatic Labeling atlas. The level of β-amyloid plaques in each region was compared among different clinical stages of Alzheimer's disease using the analysis of variance. An additional correlation analysis examined the relationship between each region of interest's cognitive performance scores and asymmetry index values. We found that β-amyloid appears to be lateralized in different stages of Alzheimer's disease. In addition, there is a significant correlation between β-amyloid asymmetry in various brain regions and cognition. The observed Aβ lateralization could potentially be utilized as a neuroimaging biomarker throughout AD progression.