scholarly journals Hemodynamic and structural brain measures in high and low sedentary older adults

2021 ◽  
pp. 0271678X2110093
Author(s):  
Carlijn M Maasakkers ◽  
Dick HJ Thijssen ◽  
Silvin P Knight ◽  
Louise Newman ◽  
John D O'Connor ◽  
...  

Due to its cardiovascular effects sedentary behaviour might impact cerebrovascular function in the long term, affecting cerebrovascular regulatory mechanisms and perfusion levels. Consequently this could underly potential structural brain abnormalities associated with cognitive decline. We therefore assessed the association between sedentary behaviour and brain measures of cerebrovascular perfusion and structural abnormalities in community-dwelling older adults. Using accelerometery (GENEActiv) data from The Irish Longitudinal Study on Ageing (TILDA) we categorised individuals by low- and high-sedentary behaviour (≤8 vs >8 hours/day). We examined prefrontal haemoglobin oxygenation levels using Near-Infrared Spectroscopy during rest and after an orthostatic challenge in 718 individuals (66 ± 8 years, 52% female). Global grey matter cerebral blood flow, total grey and white matter volume, total and subfield hippocampal volumes, cortical thickness, and white matter hyperintensities were measured using arterial spin labelling, T1, and FLAIR MRI in 86 individuals (72 ± 6 years, 55% female). While no differences in prefrontal or global cerebral hemodynamics were found between groups, high-sedentary individuals showed lower hippocampal volumes and increased white matter hyperintensities compared to their low-sedentary counterparts. Since these structural cerebral abnormalities are associated with cognitive decline and Alzheimer’s disease, future work exploring the causal pathways underlying these differences is needed.

2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Catherine M. Mewborn ◽  
Cutter A. Lindbergh ◽  
B. Randy Hammond ◽  
Lisa M. Renzi-Hammond ◽  
L. Stephen Miller

A growing literature emphasizes the importance of lifestyle factors such as nutrition in successful aging. The current study examined if one year of supplementation with lutein (L) and zeaxanthin (Z), two nutrients with known antioxidative properties and cognitive benefits, impacted structural brain outcomes in older adults using a double-blind, randomized, placebo-controlled trial design. Community-dwelling older adults (20 males and 27 females) aged 65–87 years (M = 71.8 years, SD = 6.04 years) were randomized into supplement (N = 33) and placebo groups (N = 14) using simple randomization. The supplement group received 10 mg L + 2 mg Z daily for 12 months while the placebo group received a visually identical, inert placebo. L and Z were measured via retinal concentrations (macular pigment optical density or MPOD). Structural brain outcomes, focusing on global and frontal-temporal lobe regions, were acquired using both T1-weighted and DTI MRI sequences. We hypothesized that the supplement group would increase, maintain, or show attenuated loss in hypothesized regions-of-interest (ROIs) while the placebo group would show age-related declines in brain structural integrity over the course of the trial. While results showed age-related declines for frontal and temporal gray and white matter volumes, as well as fornix white matter microstructure across both groups, only minimal differences were found between the supplement and placebo groups. However, exploratory analyses showed that individuals who responded better to supplementation (i.e., showed greater increases in MPOD) showed less decline in global and prefrontal gray matter volume than supplement “nonresponders.” While results suggest that one year of L and Z supplementation may have limited effects on structural brain outcomes overall, there may be a subsample of individuals for whom supplementation of L and Z provides greater benefits. ClinicalTrials.gov number, NCT02023645.


Neurology ◽  
2018 ◽  
Vol 90 (15) ◽  
pp. e1291-e1297 ◽  
Author(s):  
So Young Moon ◽  
Philipe de Souto Barreto ◽  
Yves Rolland ◽  
Marie Chupin ◽  
Ali Bouyahia ◽  
...  

ObjectiveTo evaluate the relationship of white matter hyperintensities (WMH) with decline in lower extremity function (LEF) over approximately 3 years in dementia-free older adults with memory complaints.MethodsWe obtained brain MRI data from 458 community-dwelling adults, aged 70 years or over, at baseline, and from 358 adults over an average follow-up of 963 days. We evaluated LEF using the Short Physical Performance Battery (SPPB). We related baseline WMH volumes and progression to SPPB scores over time, using mixed-effect linear regressions. For the secondary analyses, we categorized baseline WMH volume into quartiles, and dichotomized the WMH progression to compare fast and slow progression.ResultsBaseline WMH volume (β = −0.017, 95% confidence interval [CI] −0.025 to −0.009), as well as WMH progression (β = −0.002, 95% CI −0.003 to −0.001), significantly associated with a decline in SPPB performance in adjusted analyses. Compared with the lowest quartile of baseline WMH volume, the highest quartile associated with a decline in SPPB performance (β = −0.301, 95% CI −0.558 to −0.044). Fast progression also associated with a decline in SPPB performance. We found clinically meaningful differences in the SPPB, with higher scores in participants with slow progression of WMH, at both 24 and 36 months.ConclusionsBaseline level and WMH progression associated with longitudinal decline in SPPB performance among older adults. We detected clinically meaningful differences in SPPB performance on comparing fast with slow progression of WMH, suggesting that speed of WMH progression is an important determinant of LEF during aging.


2018 ◽  
Vol 47 (1) ◽  
pp. 57-65 ◽  
Author(s):  
Kristen L. Nowak ◽  
Linda Fried ◽  
Anna Jovanovich ◽  
Joachim Ix ◽  
Kristine Yaffe ◽  
...  

Background: Dietary sodium may influence cognitive function through its effects on cerebrovascular function and cerebral blood flow. Methods: The aim of this study was to evaluate the association of dietary sodium intake with cognitive decline in community-dwelling older adults. We also evaluated the associations of dietary potassium and sodium:potassium intake with cognitive decline, and associations of these nutrients with micro- and macro-structural brain magnetic resonance imaging (MRI) indices. In all, 1,194 participants in the Health Aging and Body Composition study with measurements of dietary sodium intake (food frequency questionnaire [FFQ]) and change in the modified Mini Mental State Exam (3MS) were included. Results: The age of participants was 74 ± 3 years with a mean dietary sodium intake of 2,677 ± 1,060 mg/day. During follow-up (6.9 ± 0.1 years), 340 (28%) had a clinically significant decline in 3MS score (≥1.5 SD of mean decline). After adjustment, dietary sodium intake was not associated with odds of cognitive decline (OR 0.96, 95% CI 0.50–1.84 per doubling of sodium). Similarly, potassium was not associated with cognitive decline; however, higher sodium:potassium intake was associated with increased odds of cognitive decline (OR 2.02 [95% CI 1.01–4.03] per unit increase). Neither sodium or potassium alone nor sodium:potassium were associated with micro- or macro-structural brain MRI indices. These results are limited by the use of FFQ. Conclusions: In community-dwelling older adults, higher sodium:potassium, but not sodium or potassium intake alone, was associated with decline in cognitive function, with no associations observed with micro- and macro-structural brain MRI indices. These findings do not support reduction dietary sodium/increased potassium intake to prevent cognitive decline with aging.


2016 ◽  
Author(s):  
RK Olsen ◽  
L-K Yeung ◽  
A Noly-Gandon ◽  
MC D’Angelo ◽  
A Kacollja ◽  
...  

AbstractWe investigated whether older adults without subjective memory complaints, but who present with cognitive decline in the laboratory, demonstrate atrophy in medial temporal lobe (MTL) subregions associated with Alzheimer's disease. Forty community-dwelling older adults were categorized based on Montreal Cognitive Assessment (MoCA) performance. Total grey/white matter, cerebrospinal fluid, and white matter hyperintensity load were quantified from whole-brain T1-weighted and FLAIR magnetic resonance imaging scans, while hippocampal subfields and MTL cortical subregion volumes (CA1, dentate gyrus/CA2/3, subiculum, anterolateral and posteromedial entorhinal, perirhinal, and parahippocampal cortices) were quantified using high-resolution T2-weighted scans. Cognitive status was evaluated using standard neuropsychological assessments. No significant differences were found in the whole-brain measures. However, MTL volumetry revealed that anterolateral entorhinal cortex (alERC) volume -- the same region in which Alzheimer's pathology originates -- was strongly associated with MoCA performance. This is the first study to demonstrate that alERC volume is related to cognitive decline in preclinical, community-dwelling older adults.


2021 ◽  
Vol 15 ◽  
Author(s):  
Rachel A. Crockett ◽  
Ryan. S. Falck ◽  
Elizabeth Dao ◽  
Chun Liang Hsu ◽  
Roger Tam ◽  
...  

Background: Falls in older adults are a major public health problem. White matter hyperintensities (WMHs) are highly prevalent in older adults and are a risk factor for falls. In the absence of a cure for WMHs, identifying potential strategies to counteract the risk of WMHs on falls are of great importance. Physical activity (PA) is a promising countermeasure to reduce both WMHs and falls risk. However, no study has yet investigated whether PA attenuates the association of WMHs with falls risk. We hypothesized that PA moderates the association between WMHs and falls risk.Methods: Seventy-six community-dwelling older adults aged 70–80 years old were included in this cross-sectional study. We indexed PA using the Physical Activity Score for the Elderly (PASE) Questionnaire. Falls risk was assessed using the Physiological Profile Assessment (PPA), and WMH volume (mm3) was determined by an experienced radiologist on T2-weighted and PD-weighted MRI scans. We first examined the independent associations of WMH volume and PASE score with PPA. Subsequently, we examined whether PASE moderated the relationship between WMH volume and PPA. We plotted simple slopes to interpret the interaction effects. Age, sex, and Montreal Cognitive Assessment (MoCA) score were included as covariates in all models.Results: Participants had a mean age of 74 years (SD = 3 years) and 54 (74%) were female. Forty-nine participants (66%) had a Fazekas score of 1, 19 (26%) had a score of 2, and 6 (8%) a score of 3. Both PASE (β = −0.26 ± 0.11; p = 0.022) and WMH volume (β = 0.23 ± 0.11; p = 0.043) were each independently associated with PPA score. The interaction model indicated that PASE score moderated the association between WMH volume and PPA (β = −0.27 ± 0.12; p = 0.030), whereby higher PASE score attenuated the association between WMHs and falls risk.Conclusion: PA is an important moderator of falls risk. Importantly, older adults with WMH can reduce their risk of falls by increasing their PA.


2009 ◽  
Vol 11 (2) ◽  
pp. 181-190 ◽  

The targeted brain dysfunction that accompanies aging can have a devastating effect on cognitive and intellectual abilities. A significant proportion of older adults experience precipitous cognitive decline that negatively impacts functional activities. Such individuals meet clinical diagnostic criteria for dementia, which is commonly attributed to Alzheimer's disease (AD). Structural neuroimaging, including magnetic resonance imaging (MRI), has contributed significantly to our understanding of the morphological and pathology-related changes that may underlie normal and disease-associated cognitive change in aging. White matter hyperintensities (WMH), which are distributed patches of increased hyperintense signal on T2-weighted MRI, are among the most common structural neuroimaging findings in older adults. In recent years, WMH have emerged as robust radiological correlates of cognitive decline. Studies suggest that WMH distributed in anterior brain regions are related to decline in executive abilities that is typical of normal aging, whereas WMH distributed in more posterior brain regions are common in AD. Although epidemiological, observational, and pathological studies suggest that WMH may be ischemic in origin and caused by consistent or variable hypoperfusion, there is emerging evidence that they may also reflect vascular deposition of beta-amyloid, particularly when they are distributed in posterior areas and are present in patients with AD. Findings from the literature highlight the potential contribution of small-vessel cerebrovascular disease to the pathogenesis of AD, and suggest a mechanistic interaction, but future longitudinal studies using multiple imaging modalities are required to fully understand the complex role of WMH in AD.


2017 ◽  
Vol 38 (6) ◽  
pp. 996-1009 ◽  
Author(s):  
Jana Kynast ◽  
Leonie Lampe ◽  
Tobias Luck ◽  
Stefan Frisch ◽  
Katrin Arelin ◽  
...  

Age-related white matter hyperintensities (WMH) are a manifestation of white matter damage seen on magnetic resonance imaging (MRI). They are related to vascular risk factors and cognitive impairment. This study investigated the cognitive profile at different stages of WMH in a large community-dwelling sample; 849 subjects aged 21 to 79 years were classified on the 4-stage Fazekas scale according to hyperintense lesions seen on individual T2-weighted fluid-attenuated inversion recovery MRI scans. The evaluation of cognitive functioning included seven domains of cognitive performance and five domains of subjective impairment, as proposed by the DSM-5. For the first time, the impact of age-related WMH on Theory of Mind was investigated. Differences between Fazekas groups were analyzed non-parametrically and effect sizes were computed. Effect sizes revealed a slight overall cognitive decline in Fazekas groups 1 and 2 relative to healthy subjects. Fazekas group 3 presented substantial decline in social cognition, attention and memory, although characterized by a high inter-individual variability. WMH groups reported subjective cognitive decline. We demonstrate that extensive WMH are associated with specific impairment in attention, memory, social cognition, and subjective cognitive performance. The detailed neuropsychological characterization of WMH offers new therapeutic possibilities for those affected by vascular cognitive decline.


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