Association of Plasma Oligomerized Amyloid-beta and Cerebral White Matter Lesions in a Health Screening Population

Abstract

Background: Cerebral white matter lesions (WML) are related to a higher risk of vascular and Alzheimer's dementia. Moreover, oligomerized amyloid-beta (OA beta) can be measured from blood for dementia screening. Objective: We aimed to investigate the relationship of plasma OA beta levels with clinical and radiological variables in a health screening population. Methods: WML, other volumetric parameters of magnetic resonance images, cognitive assessment, and plasma OA beta level were evaluated. Results: Ninety-two participants were analyzed. The majority of participants' clinical dementia rating was 0 or 0.5 (96.7%). White matter hyperintensities (WMH) increased with age, but OA beta levels did not (r(2) = 0.19, p < 0.001, r(2) = 0.03, p = 0.10, respectively). No volumetric data, including cortical thickness/hippocampal volume, showed any significant correlation with OA beta. Log-WMH volume was positively correlated with OA beta (r = 0.24, p = 0.02), and this association was significant in the periventricular area. White matter signal abnormalities from 3D-T1 images were also correlated with the OA beta in the periventricular area (p = 0.039). Multivariate linear regression showed that log-WMH values were independently associated with OA beta (B = 0.879 (95% confidence interval 0.098 -1.660, p = 0.028)). Higher tertiles of WMH showed higher OA beta levels than lower tertiles showed (p = 0.044). Using a cutoff of 0.78 ng/mL, the high OA beta group had a larger WMH volume, especially in the periventricular area, than the low OA beta group (p = 0.036). Conclusion: Both WML and plasma OA beta levels can be early markers for neurodegeneration in the healthcare population. The lesions, especially in the periventricular area, might be related to amyloid pathogenesis, which strengthens the importance of WML in the predementia stage.