The impact of anxiety on conversion from mild cognitive impairment to Alzheimer's disease

AbstractEigenvector alignment, introduced herein to investigate human brain functional networks, is adapted from methods developed to detect influential nodes and communities in networked systems. It is used to identify differences in the brain networks of subjects with Alzheimer’s disease (AD), amnestic Mild Cognitive Impairment (aMCI) and healthy controls (HC). Well-established methods exist for analysing connectivity networks composed of brain regions, including the widespread use of centrality metrics such as eigenvector centrality. However, these metrics provide only limited information on the relationship between regions, with this understanding often sought by comparing the strength of pairwise functional connectivity. Our holistic approach, eigenvector alignment, considers the impact of all functional connectivity changes before assessing the strength of the functional relationship, i.e. alignment, between any two regions. This is achieved by comparing the placement of regions in a Euclidean space defined by the network’s dominant eigenvectors. Eigenvector alignment recognises the strength of bilateral connectivity in cortical areas of healthy control subjects, but also reveals degradation of this commissural system in those with AD. Surprisingly little structural change is detected for key regions in the Default Mode Network, despite significant declines in the functional connectivity of these regions. In contrast, regions in the auditory cortex display significant alignment changes that begin in aMCI and are the most prominent structural changes for those with AD. Alignment differences between aMCI and AD subjects are detected, including notable changes to the hippocampal regions. These findings suggest eigenvector alignment can play a complementary role, alongside established network analytic approaches, to capture how the brain’s functional networks develop and adapt when challenged by disease processes such as AD.

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Alzheimer's disease and sleep disturbances: a review

Arquivos de Neuro-Psiquiatria ◽

10.1590/0004-282x20190149 ◽

2019 ◽

Vol 77 (11) ◽

pp. 815-824 ◽

Cited By ~ 2

Author(s):

Conrado Regis Borges ◽

Dalva Poyares ◽

Ronaldo Piovezan ◽

Ricardo Nitrini ◽

Sonia Brucki

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Sleep Disturbances ◽

Neurodegenerative Process ◽

Preclinical Ad ◽

Scientific Attention ◽

Meta Analyses ◽

The Impact

ABSTRACT The association between Alzheimer's disease (AD) and sleep disturbances has received increasing scientific attention in the last decades. However, little is known about the impact of sleep and its disturbances on the development of preclinical AD stages, such as mild cognitive impairment. This review describes the evolution of knowledge about the potential bidirectional relationships between AD and sleep disturbances exploring recent large prospective studies and meta-analyses and studies of the possible mechanisms through which sleep and the neurodegenerative process could be associated. The review also makes a comprehensive exploration of the sleep characteristics of older people, ranging from cognitively normal individuals, through patients with mild cognitive impairment, up to the those with dementia with AD.

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Estimation of the risk of conversion of mild cognitive impairment of Alzheimer type to Alzheimer's disease in a south Brazilian population-based elderly cohort: the PALA study

International Psychogeriatrics ◽

10.1017/s1041610211002043 ◽

2011 ◽

Vol 24 (4) ◽

pp. 674-681 ◽

Cited By ~ 7

Author(s):

Cláudia Godinho ◽

Ana Luiza Camozzato ◽

Diego Onyszko ◽

Márcia Lorena Chaves

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Population Based ◽

Alzheimer Type ◽

Risk Of Progression ◽

Elderly Cohort ◽

The Impact ◽

Cognitively Intact

ABSTRACTBackground: Higher mild cognitive impairment (MCI) prognostic variability has been related to sample characteristics (community-based or specialized clinic) and to diverse operationalization criteria. The aim of the study was to evaluate the trajectory of MCI of Alzheimer type in a population-based elderly cohort in Southern Brazil. We also estimated the risk for the development of probable Alzheimer's disease (AD) in comparison with healthy subjects.Methods: Data were derived from a population-based cohort (the PALA study). MCI outcomes were sub-classified into three categories: conversion, stabilization, and reconversion. The risk of progression to dementia was compared between MCI and normal participants. The analysis was based on 21 MCI subjects and 220 cognitively intact participants (N = 241).Results: Of the 21 MCI subjects, 38% developed dementia, 24% remained stable and 38% improved. The MCI annual conversion rate to AD was 8.5%. MCI was associated with significantly higher risk of conversion to AD (HR = 49.83, p = 0.004), after adjustment for age, education, sex and Mini-Mental State Examination score.Conclusions: Independent of the heterogeneity of the outcomes, MCI of the Alzheimer type participants showed significantly higher risk of developing probable AD, demonstrating the impact of the use of these MCI criteria that emphasize long-term episodic memory impairment.

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Multi-parametric classification of Alzheimer's disease and mild cognitive impairment: The impact of quantitative magnetization transfer MR imaging

NeuroImage ◽

10.1016/j.neuroimage.2009.07.005 ◽

2009 ◽

Vol 48 (4) ◽

pp. 657-667 ◽

Cited By ~ 27

Author(s):

Claus Kiefer ◽

Lisa Brockhaus ◽

Katja Cattapan-Ludewig ◽

Pietro Ballinari ◽

Yuliya Burren ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Mr Imaging ◽

Magnetization Transfer ◽

Parametric Classification ◽

The Impact

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White Matter Connectivity and Gray Matter Volume Changes Following Donepezil Treatment in Patients With Mild Cognitive Impairment: A Preliminary Study Using Probabilistic Tractography

Frontiers in Aging Neuroscience ◽

10.3389/fnagi.2020.604940 ◽

2021 ◽

Vol 12 ◽

Author(s):

Gwang-Won Kim ◽

Shin-Eui Park ◽

Kwangsung Park ◽

Gwang-Woo Jeong

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

White Matter ◽

Gray Matter ◽

Probabilistic Tractography ◽

Volume Changes ◽

White Matter Connectivity ◽

The Impact

The donepezil treatment is associated with improved cognitive performance in patients with mild cognitive impairment (MCI), and its clinical effectiveness is well-known. However, the impact of the donepezil treatment on the enhanced white matter connectivity in MCI is still unclear. The purpose of this study was to evaluate the thalamo-cortical white matter (WM) connectivity and cortical thickness and gray matter (GM) volume changes in the cortical regions following donepezil treatment in patients with MCI using probabilistic tractography and voxel-based morphometry. Patients with MCI underwent magnetic resonance examinations before and after 6-month donepezil treatment. Compared with healthy controls, patients with MCI showed decreased WM connectivity of the thalamo-lateral prefrontal cortex, as well as reduced thickness in the medial/lateral orbitofrontal cortices (p < 0.05). The thalamo-lateral temporal cortex connectivity in patients with MCI was negatively correlated with Alzheimer's disease assessment scale-cognitive subscale (ADAS-cog) (r = −0.76, p = 0.01). The average score of the Korean version of the mini-mental state examination (K-MMSE) in patients with MCI was improved by 7.9% after 6-months of donepezil treatment. However, the patterns of WM connectivity and brain volume change in untreated and treated patients were not significantly different from each other, resulting from multiple comparison corrections. These findings will be valuable in understanding the neurophysiopathological mechanism on MCI as a prodromal phase of Alzheimer's disease in connection with brain functional connectivity and morphometric change.

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O4-06-06: The Impact of Anosognosia and Anosodiaphoria on the Prediction of Progression from Mild Cognitive Impairment to Alzheimer's Disease

Alzheimer s & Dementia ◽

10.1016/j.jalz.2016.06.642 ◽

2016 ◽

Vol 12 ◽

pp. P346-P347 ◽

Cited By ~ 1

Author(s):

Catherine E. Munro ◽

Nancy J. Donovan ◽

Rebecca Amariglio ◽

Kate V. Papp ◽

Gad A. Marshall ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

The Impact

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DIABETES AS A RISK FACTOR FOR MILD COGNITIVE IMPAIRMENT IN OLDER RESIDENTS OF RURAL WEST TEXAS

Innovation in Aging ◽

10.1093/geroni/igz038.3160 ◽

2019 ◽

Vol 3 (Supplement_1) ◽

pp. S860-S860

Author(s):

Gabriela Arandia ◽

Annette Boles ◽

Veronica Lopez ◽

Volker Neugebauer

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Blood Sugar ◽

Control Diet ◽

West Texas ◽

Predominantly Female ◽

Sugar Levels ◽

The Impact

Abstract While a growing body of evidence suggests a link between diabetes and Alzheimer’s disease, few studies have examined the impact of diabetes on mild cognitive impairment, the precursor to Alzheimer’s disease, especially among older, rural, and ethnically diverse populations. Using data from Project FRONTIER (Facing Rural Obstacles to Healthcare Now Through Intervention, Education, & Research), a longitudinal cohort aging study in rural West Texas, the aim of this study was to compare the risk for mild cognitive impairment among participants who, according to blood sugar levels, were pre-diabetic/diabetic versus normal. This study uses baseline and 3-year follow-up data from a subsample (recruited from Cochran County) of the larger, four-county sample of Project FRONTIER. The study sample (n=206) ranged from 40 to 87 years old (mean age: 58.3 + 11.7 years old), was predominantly female (73.3%), White (88.4%), with slightly over half self-reporting as Hispanic (51.0%). Logistic regression results revealed that those who had prediabetes/diabetes had 1.81 times the risk for developing mild cognitive impairment compared to those who had normal blood sugar levels. These findings indicate the need for earlier intervention for improved diabetes prevention, self-management, and control (diet, physical activity, treatments) to help offset the development of mild cognitive impairment, which could progress to Alzheimer’s disease later in life. More research is needed to confirm the link between pre-diabetes/diabetes and mild cognitive impairment in other populations and settings.

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Apathy and Emotion-Based Decision-Making in Amnesic Mild Cognitive Impairment and Alzheimer’s Disease

Behavioural Neurology ◽

10.1155/2014/231469 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 16

Author(s):

Sophie Bayard ◽

Jean-Pierre Jacus ◽

Stéphane Raffard ◽

Marie-Christine Gely-Nargeot

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Decision Making ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Iowa Gambling Task ◽

Rating Scale ◽

Feedback Processing ◽

The Impact

Background. Apathy and reduced emotion-based decision-making are two behavioral modifications independently described in Alzheimer’s disease (AD) and amnestic mild cognitive impairment (aMCI).Objectives. The aims of this study were to investigate decision-making based on emotional feedback processing in AD and aMCI and to study the impact of reduced decision-making performances on apathy.Methods. We recruited 20 patients with AD, 20 participants with aMCI, and 20 healthy controls. All participants completed the Lille apathy rating scale (LARS) and the Iowa gambling task (IGT).Results. Both aMCI and AD participants had reduced performances on the IGT and were more apathetic compared to controls without any difference between aMCI and AD groups. For the entire sample, LARS initiation dimension was related to IGT disadvantageous decision-making profile.Conclusions. We provide the first study showing that both aMCI and AD individuals make less profitable decisions than controls, whereas aMCI and AD did not differ. Disadvantageous decision-making profile on the IGT was associated with higher level of apathy on the action initiation dimension. The role of an abnormal IGT performance as a risk factor for the development of apathy needs to be investigated in other clinical populations and in normal aging.

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