P3-266: NEUROPSYCHIATRIC SYMPTOMS AND FUNCTIONAL CONNECTIVITY IN MILD COGNITIVE IMPAIRMENT AND COGNITIVELY NORMAL ELDERLY

ABSTRACT Voxel-based morphometry (VBM) is a useful approach for investigating neurostructural brain changes in dementia. We systematically reviewed VBM studies of Alzheimer's disease (AD) and mild cognitive impairment (MCI), specifically focusing on grey matter (GM) atrophy in the frontal lobe. Methods: Two searches were performed on the Pubmed database. A set of exclusion criteria was applied to ensure the selection of only VBM studies that directly investigated GM volume abnormalities in AD and/or MCI patients compared to cognitively normal controls. Results: From a total of 46 selected articles, 35 VBM studies reported GM volume reductions in the frontal lobe. The frontal subregions, where most of the volume reductions were reported, included the inferior, superior and middle frontal gyri, as well as the anterior cingulate gyrus. We also found studies in which reduced frontal GM was detected in MCI patients who converted to AD. In a minority of studies, correlations between frontal GM volumes and behavioural changes or cognitive deficits in AD patients were investigated, with variable findings. Conclusion: Results of VBM studies indicate that the frontal lobe should be regarded as an important brain area when investigating GM volume deficits in association with AD. Frontal GM loss might not be a feature specific to late AD only. Future VBM studies involving large AD samples are warranted to further investigate correlations between frontal volume deficits and both cognitive impairment and neuropsychiatric symptoms.

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Ethnic Differences Between Hispanics and Non-Hispanic Whites in Neuropsychiatric Symptoms Predict Conversion to Mild Cognitive Impairment

Journal of Geriatric Psychiatry and Neurology ◽

10.1177/0891988720957087 ◽

2020 ◽

pp. 089198872095708

Author(s):

Bhaskar Thakur ◽

Luis Alvarado ◽

Christopher Dodoo ◽

Ricardo Salazar ◽

Alberto J. Espay ◽

...

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Ethnic Differences ◽

Primary Outcome ◽

Neuropsychiatric Symptoms ◽

Data Driven ◽

Cognitively Normal ◽

Physical Behavior ◽

Normal Individuals ◽

Normal Cognition

The aim of the study is to ascertain the neuropsychiatric symptoms (NPS) subtypes significantly influencing progression to mild cognitive impairment (MCI) by ethnicity. In this retrospective cohort study, we included 386 cognitively normal individuals participating in the longitudinal Texas Alzheimer’s Research and Care Consortium between February 2007 and August 2014. The primary outcome was time to incident MCI. Data driven NPS subtypes at baseline were identified and the effects of these subtypes on the outcome were obtained for Hispanic and non-Hispanic ethnic cohorts and summarized with a hazard ratio (HR). Three NPS subtypes were identified and internally validated: psychomotor apathy factor (including agitation, irritability, apathy), affective mood factor (including depression, anxiety), and physical behavior factor (including nighttime behavior, eating/appetite disturbances). In adjusted analysis, a psychomotor apathy score of NPS was the best predictor for MCI (HR = 2.19, p = 0.037) among non-Hispanics whereas physical behavior score was the most predictive of MCI (HR = 2.55, p = 0.029) among Hispanics. A high score of affective mood factor also tended to increase the risk of MCI (HR = 2.09, p = 0.06) in Hispanics. Progression from normal cognition to MCI was differentially predicted by NPS subtypes in Hispanics and non-Hispanic whites. These data may inform the allocation of efforts for monitoring individuals at-risk of MCI.

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Faculty Opinions recommendation of Surgery and brain atrophy in cognitively normal elderly subjects and subjects diagnosed with mild cognitive impairment.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.13988983.15768119 ◽

2012 ◽

Author(s):

Luzius A Steiner ◽

Christoph Burkhart

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Brain Atrophy ◽

Elderly Subjects ◽

Cognitively Normal

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Directed Functional Connectivity of Posterior Cingulate Cortex and Whole Brain in Alzheimer's Disease and Mild Cognitive Impairment

Current Alzheimer Research ◽

10.2174/1567205013666161201201000 ◽

2017 ◽

Vol 14 (6) ◽

pp. 628-635 ◽

Cited By ~ 17

Author(s):

Enyan Yu ◽

Zhengluan Liao ◽

Dewang Mao ◽

Qi Zhang ◽

Gongjun Ji ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Functional Connectivity ◽

Cingulate Cortex ◽

Posterior Cingulate Cortex ◽

Whole Brain ◽

Posterior Cingulate

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The Anterior-posterior Functional Connectivity Disconnection in the Elderly with Subjective Memory Impairment and Amnestic Mild Cognitive Impairment

Current Alzheimer Research ◽

10.2174/1567205017666200525015017 ◽

2020 ◽

Vol 17 (4) ◽

pp. 373-381

Author(s):

Wuhai Tao ◽

Jinping Sun ◽

Xin Li ◽

Wen Shao ◽

Jing Pei ◽

...

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Functional Connectivity ◽

Memory Impairment ◽

Amnestic Mild Cognitive Impairment ◽

Magnetic Resonance Imaging Scan ◽

Subjective Memory ◽

Long Distance ◽

Whole Brain ◽

Subjective Memory Impairment

Background: Subjective Memory Impairment (SMI) may tremendously increase the risk of Alzheimer’s Disease (AD). The full understanding of the neuromechanism of SMI will shed light on the early intervention of AD. Methods: In the current study, 23 Healthy Controls (HC), 22 SMI subjects and 24 amnestic Mild Cognitive Impairment (aMCI) subjects underwent the comprehensive neuropsychological assessment and the resting-state functional magnetic resonance imaging scan. The difference in the connectivity of the Default Mode Network (DMN) and Functional Connectivity (FC) from the Region of Interest (ROI) to the whole brain were compared, respectively. Results: The results showed that HC and SMI subjects had significantly higher connectivity in the region of the precuneus area compared to aMCI subjects. However, from this region to the whole brain, SMI and aMCI subjects had significant FC decrease in the right anterior cingulum, left superior frontal and left medial superior frontal gyrus compared to HC. In addition, this FC change was significantly correlated with the cognitive function decline in participants. Conclusion: Our study indicated that SMI subjects had relatively intact DMN connectivity but impaired FC between the anterior and posterior brain. The findings suggest that long-distance FC is more vulnerable than the short ones in the people with SMI.

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Lower functional hippocampal redundancy in mild cognitive impairment

Translational Psychiatry ◽

10.1038/s41398-020-01166-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Stephanie Langella ◽

◽

Muhammad Usman Sadiq ◽

Peter J. Mucha ◽

Kelly S. Giovanello ◽

...

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Cognitive Decline ◽

Resting State ◽

Memory Performance ◽

Potential Mechanism ◽

Network Efficiency ◽

Cognitively Normal ◽

Normal Individuals ◽

The Relationship

AbstractWith an increasing prevalence of mild cognitive impairment (MCI) and Alzheimer’s disease (AD) in response to an aging population, it is critical to identify and understand neuroprotective mechanisms against cognitive decline. One potential mechanism is redundancy: the existence of duplicate elements within a system that provide alternative functionality in case of failure. As the hippocampus is one of the earliest sites affected by AD pathology, we hypothesized that functional hippocampal redundancy is protective against cognitive decline. We compared hippocampal functional redundancy derived from resting-state functional MRI networks in cognitively normal older adults, with individuals with early and late MCI, as well as the relationship between redundancy and cognition. Posterior hippocampal redundancy was reduced between cognitively normal and MCI groups, plateauing across early and late MCI. Higher hippocampal redundancy was related to better memory performance only for cognitively normal individuals. Critically, functional hippocampal redundancy did not come at the expense of network efficiency. Our results provide support that hippocampal redundancy protects against cognitive decline in aging.

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