Association of plasma amyloid-β oligomerization with theta/beta ratio in older adults

Heewon Bae; Min Ju Kang; Sang-Won Ha; Da-Eun Jeong; Kiwon Lee; Seungui Lim; Jin-Young Min; Kyoung-Bok Min

doi:10.3389/fnagi.2023.1291881

Association of plasma amyloid-β oligomerization with theta/beta ratio in older adults

Front Aging Neurosci. 2023 Dec 1:15:1291881. doi: 10.3389/fnagi.2023.1291881. eCollection 2023.

Authors

Heewon Bae^{1

2}, Min Ju Kang³, Sang-Won Ha³, Da-Eun Jeong³, Kiwon Lee⁴, Seungui Lim⁴, Jin-Young Min¹, Kyoung-Bok Min^{5

6}

Affiliations

¹ Veterans Medical Research Institute, Veterans Health Service Medical Center, Seoul, Republic of Korea.
² Department of Clinical Research Design and Evaluation, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul, Republic of Korea.
³ Department of Neurology, Veterans Health Service Medical Center, Seoul, Republic of Korea.
⁴ Ybrain Research Institute, Seongnam-si, Republic of Korea.
⁵ Department of Preventive Medicine, College of Medicine, Seoul National University, Seoul, Republic of Korea.
⁶ Medical Research Center, Institute of Health Policy and Management, Seoul National University, Seoul, Republic of Korea.

Abstract

Background: Oligomeric Aβ (OAβ) is a promising candidate marker for Alzheimer's disease (AD) diagnosis. Electroencephalography (EEG) is a potential tool for early detection of AD. Still, whether EEG power ratios, particularly the theta/alpha ratio (TAR) and theta/beta ratio (TBR), reflect Aβ burden-a primary mechanism underlying cognitive impairment and AD. This study investigated the association of TAR and TBR with amyloid burden in older adults based on MDS-OAβ levels.

Methods: 529 individuals (aged ≥60 years) were recruited. All participants underwent EEG (MINDD SCAN, Ybrain Inc., South Korea) and AlzOn™ test (PeopleBio Inc., Gyeonggi-do, Republic of Korea) for quantifying MDS-OAβ values in the plasma. EEG variables were log-transformed to normalize the data distribution. Using the MDS-OAβ cutoff value (0.78 ng/mL), all participants were classified into two groups: high MDS-OAβ and low MDS-OAβ.

Results: Participants with high MDS-OAβ levels had significantly higher TARs and TBRs than those with low MDS-OAβ levels. The log-transformed TBRs in the central lobe (β = 0.161, p = 0.0026), frontal lobe (β = 0.145, p = 0.0044), parietal lobe (β = 0.166, p = 0.0028), occipital lobe (β = 0.158, p = 0.0058), and temporal lobe (beta = 0.162, p = 0.0042) were significantly and positively associated with increases in MDS-OAβ levels. After adjusting for the Bonferroni correction, the TBRs in all lobe regions, except the occipital lobe, were significantly associated with increased MDS-OAβ levels.

Conclusion: We found a significant association of MDS-OAβ with TBR in older adults. This finding indicates that an increase in amyloid burden may be associated with an increase in the low-frequency band and a decrease in the relatively high-frequency band.

Keywords: Alzheimer’s disease; EEG; amyloid oligomers; cognitive impairment; neurotox.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This research was supported by the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI) and Korea Dementia Research Center (KDRC), funded by the Ministry of Health & Welfare and Ministry of Science and ICT, Republic of Korea (grant number: HU20C0487). This work was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and Technology (grant number, 2022R1A2C2010463).