Altered Neuronal Activity Topography Markers in the Elderly with Increased Atherosclerosis.

Takashi Shibata,Yukio Kosugi,Karin Hayashi,Satoshi Kuroda,Kiyotaka Nemoto,Yohei Kobayashi,Takashi Asada,Toshimitu Musha,Yukio Horie,Mieko Tanaka,Haruyasu Matsuzaki,Naoya Kuwayama,Michiya Kubo

doi:10.3389/fnagi.2017.00216

Abstract

Background: Previously, we reported on vascular cognitive impairment (VCI) templates, consisting of patients with VCI associated with carotid stenosis (>60%) using a quantitative electroencephalographic (EEG) technique called neuronal activity topography (NAT). Here using the VCI templates, we investigated the hypothesis that internal carotid artery–intima-media thickness (ICA–IMT) is associated with EEG spectrum intensity (sNAT) and spectrum steepness (vNAT).Methods: A total of 221 community-dwelling elderly subjects were recruited. Four groups were classified according to quartiles of ICA–IMT as assessed by ultrasonography: control group A, normal (≤0.9 mm); group B, mild atherosclerosis (1−1.1 mm); group C, moderate atherosclerosis (1.2−1.8 mm); and group D, severe atherosclerosis (≥1.9 mm). EEG markers of power ratio index (PRI), and the binary likelihood of being in the VCI group vs. the that of being in control group A (sLx:VCI−A, vLx:VCI−A) were assessed, respectively. Differences in mean total scores for PRI, sLx:VCI−A, vLx:VCI−A, between control group A and the other groups were compared using Dunnett's test, respectively.Results: The mean total scores of the PRI were 3.25, 3.00, 2.77, and 2.26 for groups A, B, C, and D, respectively. There was a significant decrease in the PRI in group D compared with group A (P = 0.0066). The mean total scores of the sLx:VCI−A were −0.14, −0.11, −0.1, and −0.03 for groups A, B, C, and D, respectively. The sLx:VCI−A in group D was significantly higher compared to that in group A (P < 0.0001). The mean total scores of the vLx:VCI−A were −0.04,−0.01, 0.01, and 0.06 for group A, B, C, and D, respectively. The vLx:VCI−A in group D and group C was significantly higher compared to that in group A, respectively (P < 0.0001, P = 0.02).Conclusion: Community-dwelling elderly subjects in the increased carotid atherosclerosis of ICA–IMT (≥1.9 mm) were at greatest risk of an EEG change as assessed by NAT.

Highlights

The carotid bifurcation and the proximal part of the internal carotid artery (ICA) are predilection sites for atherosclerotic plaques
Previously, we reported on vascular cognitive impairment (VCI) templates, consisting of patients with VCI associated with carotid stenosis (>60%) using a quantitative electroencephalographic (EEG) technique called neuronal activity topography (NAT)
Using the VCI templates, we investigated the hypothesis that internal carotid artery–intima-media thickness (ICA–IMT) is associated with EEG spectrum intensity and spectrum steepness

Summary

Introduction

The carotid bifurcation and the proximal part of the internal carotid artery (ICA) are predilection sites for atherosclerotic plaques. The role of subclinical atherosclerosis in cognitive function can be studied by ultrasound measurement of the carotid arteries and neuropsychological tests. Previous studies indicate that patients with carotid stenosis have markedly poorer scores on cognitive tests compared with control subjects (Rao, 2001; Johnston et al, 2004; Mathiesen et al, 2004; Arntzen and Mathiesen, 2011). Most patients with subclinical carotid atherosclerosis have only minor impairments of cognitive function, and standard tests (e.g., the Mini-Mental State Examination: MMSE) are not sufficiently sensitive to detect such impairments. Using the VCI templates, we investigated the hypothesis that internal carotid artery–intima-media thickness (ICA–IMT) is associated with EEG spectrum intensity (sNAT) and spectrum steepness (vNAT)

Methods

Results

Discussion

Conclusion