Authors: Seung Wan Kang, Seong Hye Choi, Jee Hyang Jeong, Jae‐Won Jang, Kyung‐Won Park, Eun‐Joo Kim, Hee Jin Kim, Jin Yong Hong, Soo Jin Yoon, Bora Yoon, Dong Won Kang
Published: 2020-12-07
DOI: 10.1002/alz.044300
Source: Full article
AbstractBackgroundAlzheimer’s disease (AD) is the most common cause of dementia. However, accumulation of beta amyloid plague in the brain which is main pathology of AD could show the various spectrum of cognitive functional stage from preclinical level to overt dementia. It is important to understand functional differences between dementia and non‐dementia of AD to predict progression forward to dementia at prodromal or preclinical stage of AD.MethodNineteen channels of resting state EEGs were measured from 45 Alzheimer’s disease subjects who were all confirmed by brain amyloid‐beta PET. Neurocognitive test, activity of daily living (ADL) and MRI were conducted for clinical diagnosis. EEG power spectrum analysis and band‐power ratio, cortical source current density estimated by standardized low resolution brain electromagnetic tomography(sLORETA), functional connectivity between 68 region of interest (ROI) based on imaginary coherence(iCoh) and complex brain networks were analyzed.Result20 AD subjects (age: 76.8±7.54) were assessed as dementia, and the other 25 (age: 72.1±6.89) as mild cognitive impairment (MCI) or subjective cognitive decline (SCD) depending on delayed recall memory score. Average CDR was 0.23 in non‐dementia and 1.15 in dementia group. There was no significant difference at delta, but theta power of AD dementia group was significantly increased at all 19 scalp channels. Mid frontal channel (Fz) showed the most distinctive enhancement of theta power. In other hands, beta1 (12∼15Hz) was significantly increased at both temporoparietal area in non‐dementia AD group. These patterns about theta increase and beta 1 decrease in AD dementia group were observed very similarly in cortical source current density. iCoh among ROIs of default mode network (DMN) was significantly decreased at alpha2 band (10∼12Hz). At bilateral frontal pole, rostral middle frontal, anterior cingulate, parahippocampus and precuneus, the degree centrality and characteristic path length significant increased at theta band. In contrast, theta of cluster coefficient and closeness centrality significantly decreased.ConclusionAD dementia showed increase of theta and decrease of bet1 both at scalp and cortical level comparing to non‐dementia AD subjects. Both global and local network efficiencies via theta wave were significantly deteriorated in AD dementia. QEEG could well discriminate the differences between dementia and non‐dementia in ADs.