White Matter Microstructure is Associated with Serum Clusterin and Everyday Functioning in a Sample of Nondemented Older Adults

Background: Although clusterin-a protein involved in lipid metabolism, amyloid beta clearance, and myelination-has been linked to gray matter atrophy within samples of older adults at risk for Alzheimer’s disease, research exploring associations with white matter (WM) micro- and macro- structural markers are largely limited. Objective:: The current study [1] explored associations between serum clusterin protein levels and WM micro- and macro- structural markers, and [2] clarified whether variations in WM fractional anisotropy (FA) were associated with functional abilities within in a racially homogenous sample of relatively well-educated older adults free of dementia. Methods: Participants underwent magnetic resonance imaging (MRI) brain exams and a blood draw and completed a performance-based measure of everyday functioning. Multiple linear regression adjusting for age, sex, APOE e4 positivity, and vascular risk were used to explore serum clusterin associations with WM metrics, as well clarify potential links between WM microstructure and everyday functioning. Results: Higher serum clusterin was associated with lower FA in several thalamocortical (anterior and posterior internal capsule, posterior thalamic radiation; ßs = -.32 to -.37, ps = .01 to .02) and association fiber tracts (external capsule, superior longitudinal fasciculus; ßs = -.32 to -.40, ps = .02). Serum clusterin was not associated with white matter hyperintensity volume (ß = .14, p = .28), but higher FA of several WM tracts was associated with better performance on the Independent Living Scale (ßs = .37 to .53, ps = .006 to .03). Conclusion: Serum clusterin is differentially associated with WM metrics, and WM microstructure is associated with everyday functioning.

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Interaction of Age and Self-reported Physical Sports Activity on White Matter Hyperintensity Volume in Healthy Older Adults

Frontiers in Aging Neuroscience ◽

10.3389/fnagi.2020.576025 ◽

2020 ◽

Vol 12 ◽

Author(s):

Mary Kathryn Franchetti ◽

Pradyumna K. Bharadwaj ◽

Lauren A. Nguyen ◽

Emily J. Van Etten ◽

Yann C. Klimentidis ◽

...

Keyword(s):

Older Adults ◽

White Matter ◽

White Matter Hyperintensity ◽

Sports Activity ◽

Healthy Older Adults

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An Ambient Assisted Living platform for supporting aging in place of pre-frail and frail older adults: Rationale, HomeAssist plaform, quasi-experimental design, and baseline characteristics. (Preprint)

10.2196/preprints.33351 ◽

2021 ◽

Author(s):

helene sauzeon ◽

Arlette Edjolo ◽

Hélène Amieva ◽

Charles Consel ◽

Karine Pérès

Keyword(s):

Older Adults ◽

Assisted Living ◽

Independent Living ◽

Aging In Place ◽

Ambient Assisted Living ◽

Large Set ◽

Everyday Functioning ◽

Frail Older Adults ◽

Outcomes Measures ◽

Quasi Experimental

UNSTRUCTURED Background: Ambient Assisted Living (AAL) technology is expected as a promising way for prolonging the aging in place. Very few evidence-based results are provided support to its real value, notably for frail older adults who have high risk of autonomy loss and of entering in nursing home. Objective: HomeAssist (HA) is a human-centered AAL platform offering a large set of applications for three main age-related need domains (Activities of Daily Living, Safety and Social participation), relying on a basic set of entities (sensors, actuators...). The HA intervention involves monitoring as well as assistive services to support independent living at home. The primary outcomes measures are related to aging in place in terms of effectiveness (institutionalization and hospitalization rates) and efficiency (everyday functioning indices). Secondary outcomes measures include indices of frailty, cognitive functioning, and psychosocial health of participants and their caregivers. Every 6 months, user experience and attitudes towards HA are also collected in equipped participants. Concomitantly, HA usages are collected. Methods: A study assessing the HA efficacy has been designed and is now conducted with 131 older adults aged 81.9 (±6.0) years (from autonomous to frail) who lived alone. The study design is quasi-experimental with a duration of 12 months optionally extensible to 24 months. It includes equipped participants, matched with non-equipped participants (n= 474). Follow-up assessments occurred at 0, 12 and 24 months. Results: The expected results are to inform the AAL value for independent living, but also to yield informed analysis on AAL usages and adoption in frail older individuals.

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Diffusion Tensor Imaging and Fiber Tractography

Handbook of Research on Advanced Techniques in Diagnostic Imaging and Biomedical Applications ◽

10.4018/978-1-60566-314-2.ch015 ◽

2009 ◽

pp. 229-246

Author(s):

Evanthia E. Tripoliti ◽

Dimitrios I. Fotiadis ◽

Konstantia Veliou

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Diffusion Tensor ◽

Brain Regions ◽

Cerebral White Matter ◽

Tissue Microstructure ◽

Diffusion Weighted Images ◽

Fiber Tracts ◽

Diffusion Weighted ◽

Magnetic Resonance Imaging Mri

Diffusion Tensor Imaging (DTI) is a magnetic resonance imaging (MRI) modality which can significantly improve our understanding of the brain structures and neural connectivity. DTI measures are thought to be representative of brain tissue microstructure and are particularly useful for examining organized brain regions, such as white matter tract areas. DTI measures the water diffusion tensor using diffusion weighted pulse sequences which are sensitive to microscopic random water motion. The resulting diffusion weighted images (DWI) display and allow quantification of how water diffuses along axes or diffusion encoding directions. This can help to measure and quantify the tissue’s orientation and structure, making it an ideal tool for examining cerebral white matter and neural fiber tracts. In this chapter the authors discuss the theoretical aspects of DTI, the information that can be extracted from DTI data, and the use of the extracted information for the reconstruction of fiber tracts and the diagnosis of a disease. In addition, a review of known fiber tracking algorithms is presented.

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Oxidized Products of Omega-6 and Omega-3 Long Chain Fatty Acids Are Associated with Increased White Matter Hyperintensity and Poorer Executive Function Performance in a Cohort of Cognitively Normal Hypertensive Older Adults

Journal of Alzheimer s Disease ◽

10.3233/jad-191197 ◽

2020 ◽

Vol 74 (1) ◽

pp. 65-77 ◽

Cited By ~ 2

Author(s):

Lynne Shinto ◽

David Lahna ◽

Charles F. Murchison ◽

Hiroko Dodge ◽

Kirsten Hagen ◽

...

Keyword(s):

Older Adults ◽

Fatty Acids ◽

White Matter ◽

White Matter Hyperintensity ◽

Long Chain Fatty Acids ◽

Omega 3 ◽

Cognitively Normal ◽

Omega 6 ◽

Oxidized Products ◽

Long Chain

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White matter microstructural abnormalities in families multiply affected with bipolar I disorder: a diffusion tensor tractography study

Psychological Medicine ◽

10.1017/s0033291713002845 ◽

2013 ◽

Vol 44 (10) ◽

pp. 2139-2150 ◽

Cited By ~ 19

Author(s):

L. Emsell ◽

C. Chaddock ◽

N. Forde ◽

W. Van Hecke ◽

G. J. Barker ◽

...

Keyword(s):

White Matter ◽

Diffusion Tensor ◽

Internal Capsule ◽

Type I ◽

Genetic Liability ◽

Inferior Longitudinal Fasciculus ◽

Participant Group ◽

Dti Tractography ◽

Magnetic Resonance Imaging Mri ◽

Diffusion Tensor Imaging Dti

BackgroundWhite matter (WM) abnormalities are proposed as potential endophenotypic markers of bipolar disorder (BD). In a diffusion tensor imaging (DTI) voxel-based analysis (VBA) study of families multiply affected with BD, we previously reported that widespread abnormalities of fractional anisotropy (FA) are associated with both BD and genetic liability for illness. In the present study, we further investigated the endophenotypic potential of WM abnormalities by applying DTI tractography to specifically investigate tracts implicated in the pathophysiology of BD.MethodDiffusion magnetic resonance imaging (MRI) data were acquired from 19 patients with BD type I from multiply affected families, 21 of their unaffected first-degree relatives and 18 healthy volunteers. DTI tractography was used to identify the cingulum, uncinate fasciculus (UF), arcuate portion of the superior longitudinal fasciculus (SLF), inferior longitudinal fasciculus (ILF), corpus callosum, and the anterior limb of the internal capsule (ALIC). Regression analyses were conducted to investigate the effect of participant group and genetic liability on FA and radial diffusivity (RD) in each tract.ResultsWe detected a significant effect of group on both FA and RD in the cingulum, SLF, callosal splenium and ILF driven by reduced FA and increased RD in patients compared to controls and relatives. Increasing genetic liability was associated with decreased FA and increased RD in the UF, and decreased FA in the SLF, among patients.ConclusionsWM microstructural abnormalities in limbic, temporal and callosal pathways represent microstructural abnormalities associated with BD whereas alterations in the SLF and UF may represent potential markers of endophenotypic risk.

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Estimated regional white matter hyperintensity burden, resting state functional connectivity, and cognitive functions in older adults

American Journal of Geriatric Psychiatry ◽

10.1016/j.jagp.2021.07.015 ◽

2021 ◽

Author(s):

Abhishek Jaywant ◽

Katharine Dunlop ◽

Lindsay W. Victoria ◽

Lauren Oberlin ◽

Charles J. Lynch ◽

...

Keyword(s):

Older Adults ◽

White Matter ◽

Functional Connectivity ◽

Cognitive Functions ◽

Resting State ◽

White Matter Hyperintensity ◽

Resting State Functional Connectivity

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Regional Hypoperfusion Predicts Decline in Everyday Functioning at Three-Year Follow-Up in Older Adults without Dementia

Journal of Alzheimer s Disease ◽

10.3233/jad-200490 ◽

2020 ◽

Vol 77 (3) ◽

pp. 1291-1304

Author(s):

Danielle L. Sanchez ◽

Kelsey R. Thomas ◽

Emily C. Edmonds ◽

Mark W. Bondi ◽

Katherine J. Bangen ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Older Adults ◽

Alzheimer's Disease ◽

Cerebral Metabolism ◽

Functional Decline ◽

Amyloid Β ◽

Cognitive Status ◽

White Matter Hyperintensity ◽

Everyday Functioning

Background: Increasing evidence indicates that cerebrovascular dysfunction may precede cognitive decline in aging and Alzheimer’s disease (AD). Reduced cerebral blood flow (CBF) is associated with cognitive impairment in older adults. However, less is known regarding the association between CBF and functional decline, and whether CBF predicts functional decline beyond cerebrovascular and metabolic risk factors. Objective: To examine the association between regional CBF and functional decline in nondemented older adults. Method: One hundred sixty-six (N = 166) participants without dementia from the Alzheimer’s Disease Neuroimaging Initiative underwent neuropsychological testing and neuroimaging. Pulsed arterial spin labeling magnetic resonance imaging was acquired to quantify resting CBF. Everyday functioning was measured using the Functional Assessment Questionnaire at baseline and annual follow-up visit across three years. Results: Adjusting for age, education, sex, cognitive status, depression, white matter hyperintensity volume, cerebral metabolism, and reference (precentral) CBF, linear mixed effects models showed that lower resting CBF at baseline in the medial temporal, inferior temporal, and inferior parietal lobe was significantly associated with accelerated decline in everyday functioning. Results were similar after adjusting for conventional AD biomarkers, including cerebrospinal fluid (CSF) amyloid-β (Aβ) and hyperphosphorylated tau (p-tau) and apolipoprotein E (APOE) ɛ4 positivity. Individuals who later converted to dementia had lower resting CBF in the inferior temporal and parietal regions compared to those who did not. Conclusion: Lower resting CBF in AD vulnerable regions including medial temporal, inferior temporal, and inferior parietal lobes predicted faster rates of decline in everyday functioning. CBF has utility as a biomarker in predicting functional declines in everyday life and conversion to dementia.

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