P1-427: AMYLOID-β AND ITS ASSOCIATION WITH CORTICAL THICKNESS, MEMORY, AND COGNITIVE COMPLAINTS IN OLDER ADULTS

Background: Previous research has identified a small subgroup of older adults that maintain a high level of cognitive functioning well into advanced age. Investigation of those with superior cognitive performance (SCP) for their age is important, as age-related decline has previously been thought to be inevitable. Objective: Preservation of cortical thickness and volume was evaluated in 76 older adults with SCP and 100 typical older adults (TOAs) assessed up to five times over six years. Methods: Regions of interest (ROIs) found to have been associated with super-aging status (a construct similar to SCP status) in previous literature were investigated, followed by a discovery phase analyses of additional regions. SCPs were aged 70 + at baseline, scoring at/above normative memory (CVLT-II) levels for demographically similar individuals aged 30–44 years old, and in the unimpaired range for all other cognitive domains over the course of the study. Results: In linear mixed models, following adjustment for multiple comparisons, there were no significant differences between rates of thinning or volume atrophy between SCPs and TOAs in previously identified ROIs, or the discovery phase analyses. With only amyloid-β negative individuals in the analyses, again there were no significant differences between SCPs and TOAs. Conclusion: The increased methodological rigor in classifying groups, together with the influence of cognitive reserve, are discussed as potential factors accounting for our findings as compared to the extant literature on those with superior cognitive performance for their age.

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Social network characteristics moderate associations between cortical thickness and cognitive functioning in older adults

Alzheimer s & Dementia ◽

10.1002/alz.12383 ◽

2021 ◽

Author(s):

Neika Sharifian ◽

Afsara B. Zaheed ◽

Emily P. Morris ◽

Ketlyne Sol ◽

Jennifer J. Manly ◽

...

Keyword(s):

Older Adults ◽

Social Network ◽

Cognitive Functioning ◽

Cortical Thickness ◽

Network Characteristics

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Synergistic Effect of Serum Homocysteine and Diabetes Mellitus on Brain Alterations

Journal of Alzheimer s Disease ◽

10.3233/jad-210036 ◽

2021 ◽

pp. 1-9

Author(s):

Gihwan Byeon ◽

Min Soo Byun ◽

Dahyun Yi ◽

Jun Ho Lee ◽

So Yeon Jeon ◽

...

Keyword(s):

Diabetes Mellitus ◽

Older Adults ◽

Cognitive Decline ◽

Brain Atrophy ◽

Homocysteine Level ◽

Cognitive Impairments ◽

Interactive Effect ◽

Brain Mri ◽

Amyloid Β ◽

Serum Homocysteine

Background: Both elevated blood homocysteine and diabetes mellitus (DM) are related to cognitive impairments or dementia. A previous study also demonstrated that the association between homocysteine and cognitive decline was much stronger in individuals with DM than in those without DM. Objective: This study aimed to examine the interactive effect of blood homocysteine and DM on brain pathological changes including brain atrophy, amyloid-β and tau deposition, and small vessel disease (SVD) related to cognitive impairments. Methods: A total of 430 non-demented older adults underwent comprehensive clinical assessment, measurement of serum homocysteine level, [11C] Pittsburgh Compound B (PiB) PET, [18F] AV-1451 PET, and brain MRI. Results: The interactive effect of homocysteine with the presence of DM on brain atrophy, especially in aging-related brain regions, was significant. Higher homocysteine concentration was associated with more prominent brain atrophy in individuals with DM, but not in those without DM. In contrast, interaction effect of homocysteine and DM was found neither on Alzheimer’s disease (AD) pathologies, including amyloid-β and tau deposition, nor white matter hyperintensity volume as a measure of SVD. Conclusion: The present findings suggest that high blood homocysteine level and DM synergistically aggravate brain damage independently of AD and cerebrovascular disease. With regard to preventing dementia or cognitive decline in older adults, these results support the importance of strictly controlling blood glucose in individuals with hyperhomocysteinemia and lowering blood homocysteine level in those with DM.

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IC-P-091: Diffusion Tensor MRI in Preclinical Alzheimer's Disease: Decreased Fractional Anisotropy in Parahippocampal White Matter in MCI and Older Adults with Cognitive Complaints

Alzheimer s & Dementia ◽

10.1016/j.jalz.2010.05.105 ◽

2010 ◽

Vol 6 ◽

pp. S37-S38 ◽

Cited By ~ 2

Author(s):

Yang Wang ◽

John D. West ◽

Laura A. Flashman ◽

Heather A. Wishart ◽

Laura A. Rabin ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Older Adults ◽

Alzheimer's Disease ◽

White Matter ◽

Fractional Anisotropy ◽

Diffusion Tensor ◽

Diffusion Tensor Mri ◽

Cognitive Complaints ◽

Preclinical Alzheimer’S Disease

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Amyloid‐ β , cortical thickness, and subsequent cognitive decline in cognitively normal oldest‐old

Annals of Clinical and Translational Neurology ◽

10.1002/acn3.51273 ◽

2021 ◽

Vol 8 (2) ◽

pp. 348-358

Author(s):

Wiesje Pelkmans ◽

Nienke Legdeur ◽

Mara Kate ◽

Frederik Barkhof ◽

Maqsood M. Yaqub ◽

...

Keyword(s):

Cognitive Decline ◽

Cortical Thickness ◽

Oldest Old ◽

Amyloid Β ◽

Cognitively Normal

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Peripheral Inflammatory Biomarkers Predict the Deposition and Progression of Amyloid-β in Cognitively Unimpaired Older Adults

Brain Behavior and Immunity ◽

10.1016/j.bbi.2021.03.015 ◽

2021 ◽

Author(s):

Lauren E. Oberlin ◽

Kirk I. Erickson ◽

Rachel Mackey ◽

William E. Klunk ◽

Howard Aizenstein ◽

...

Keyword(s):

Older Adults ◽

Amyloid Β ◽

Inflammatory Biomarkers

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A-9 Examining Neural Variability during Dual-Task Walking and Cortical Thickness in Older Adults

Archives of Clinical Neuropsychology ◽

10.1093/arclin/acab062.27 ◽

2021 ◽

Vol 36 (6) ◽

pp. 1048-1048

Author(s):

Daliah Ross ◽

Mark E Wagshul ◽

Meltem Izzetoglu ◽

Roee Holtzer

Keyword(s):

Older Adults ◽

Prefrontal Cortex ◽

Cortical Thickness ◽

Dual Task ◽

Near Infrared ◽

Adverse Outcomes ◽

Functional Near Infrared Spectroscopy ◽

Single Task ◽

Mobility Impairments ◽

Neural Variability

Abstract Objective Greater intraindividual variability (IIV) in behavioral and cognitive performance is a risk factor for adverse outcomes but research concerning IIV in neural signal is scarce. Using functional near-infrared spectroscopy (fNIRS), we showed that IIV in oxygenated hemoglobin (HbO2) levels in the prefrontal cortex increased from single task (Single-Task-Walk–STW; Single-Task-Alpha–STA) to Dual-Task-Walk (DTW) conditions in older adults. Herein, we predicted that, consistent with the neural inefficiency hypothesis, reduced cortical thickness would be associated with greater increases in IIV in fNIRS-derived HbO2 from single tasks to DTW when adjusting for behavioral performance. Method Participants were right-handed older adults without dementia recruited from the community (N = 55; M(SD) age = 74.84(4.97); %female = 49.1). Neuroimaging included fNIRS for HbO2 levels in the prefrontal cortex during tasks and MRI for cortical thickness. IIV was operationalized using the SD of fNIRS-derived HbO2 observations assessed during a 30-s interval in each experimental condition. Results Moderation analyses, assessed through linear mixed effects models, revealed that in several frontal (p < 0.02), parietal (p < 0.02), temporal (p < 0.01), and occipital (p < 0.01) regions, thinner cortex was associated with greater increases in HbO2 IIV from the single tasks to DTW. Conclusion Reduced cortical thickness was associated with inefficient increases in IIV in fNIRS-derived HbO2 from single tasks to dual-task walking. Worse IIV in gait performance under DTW predicts adverse mobility outcomes. Reduced cortical thickness and worse IIV of fNIRS-derived HbO2 during DTW are possible brain mechanisms that explain the risk of developing mobility impairments in aging and disease populations.

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