Physical activity and risk of cognitive impairment and dementia in elderly persons

[Physical activity in the elderly with other major neurocognitive disorders]

For decades, the literature was skeptical about the feasibility of motor rehabilitation and its impact, as well as that of physical activity (PA), in subjects with major neurocognitive disorders (MNCD), including Alzheimer's disease. Now, authors report several benefits of PA, both physical and cognitive, by promoting brain perfusion, neurogenesis and synaptic plasticity, as well as decreasing oxidative stress and inflammation. PA should be recommended in cases of TNCM.

Processing speed mediates the association between physical activity and executive functioning in elderly adults

Advanced aging is associated with cognitive decline. To decrease the healthcare system and socio-economic burdens as well as to promote better quality of life, is important to uncover the factors that may be related to the delay of cognitive impairments in older adults. This study investigated the relationship between physical activity levels, sedentary behavior and cardiorespiratory fitness with cognitive functioning in healthy older adults. Furthermore, it examined the mediating role of processing speed on the association between physical activity and executive functions and long-term memory. Thirty-two individuals aged between 63 and 77 years (M = 68.16, SD = 3.73) underwent measurements of maximal oxygen uptake (VO₂peak), 1-week of PA accelerometer measurement and a comprehensive cognitive assessment. Significant associations were observed between MVPA and cognitive processing speed. Equally, a significant positive indirect effect of MVPA on executive functioning and long-term memory was mediated by processing speed. Also, MVPA levels differentiated cognitive functioning in older adults – the physical active group outperformed the physical inactive group in processing speed, executive functions, and language abilities. Our results contribute to the literature on the MVPA levels as an important tool to promote healthier cognitive aging.

Association between playing cards/mahjong and risk of incident dementia among the Chinese older adults: a prospective cohort study

Objectives: Studies have shown that the frequent participation of the elderly in cognitive stimulation activities is associated with a reduced risk of dementia, but the prospective evidence of this association is limited.

Methods: We used data from a prospective cohort study of the Chinese Longitudinal Healthy Longevity Survey (CLHLS), and included 11,821 community-living Chinese individuals aged 65 years or older at 2008 baseline who were free of dementia, and were followed up every 2–3 years until 2018. Cox proportional hazards models were applied to generate the hazard ratios (HRs) and 95% confidence intervals (CIs) for analyzing the associations between the frequency of playing cards/mahjong and the incidence of dementia.

Results: A total of 821 participants were diagnosed with dementia during the 10-year follow-up. The average age of patients with dementia and non dementia were 89 and 90 years old, respectively. Compared with participants who rarely or never played cards/mahjong, participants who played cards/mahjong almost every day had a significantly lower risk of dementia (HR = 0.63; 95%CI, 0.42–0.95) after the multivariable-adjusted model. Similar results were observed in subgroup analyses based on sex (male: HR = 0.52, 0.28–0.96; female: HR = 0.62, 0.36–0.98), age (<85years: HR = 0.55, 0.32–0.89), regularly exercise (yes: HR = 0.44, 0.28–0.87) and MMSE score [above median (25): HR = 0.66, 0.41–0.92].

Conclusions: Playing cards/mahjong in the elderly may contribute to reducing the risk of dementia.

Metamemory mediates the protective effect of cognitive reserve on episodic memory during aging

The present study investigated the impact of cognitive reserve on episodic memory and metamemory control during aging using a multidimensional index of cognitive reserve and a measure of metamemory control abilities. We tested the hypotheses that cognitive reserve may play a protective role against age-related differences in episodic memory and metamemory control and that metamemory control may mediate the effect of cognitive reserve on episodic memory during aging. Young and older adults carried out a readiness-recall task in which task difficulty was manipulated through a variation of the nature of the cue-target pair link (weak vs. strong semantic associates). Episodic memory was assessed through recall performance, and metamemory by a task difficulty index reflecting the ability to adjust study time to task difficulty. Results confirmed that older adults recall fewer words, indicating an age-related deficit in episodic memory, and that older adults adjust less to task difficulty, suggesting impaired metamemory control. Findings also showed that metamemory control moderates the age-related decline in episodic memory and that cognitive reserve plays a protective role against age-related deficits in episodic memory and metamemory control. In addition, metamemory abilities mediated the beneficial effect of cognitive reserve on episodic memory performance during aging. Hence, this study sheds new light on the mechanisms underlying the impact of cognitive reserve on cognitive aging, highlighting the role of metacognitive processes.

Effects of aerobic exercise on event-related potentials related to cognitive performance: a systematic review

Introduction

Aerobic exercise interventions may affect different cognitive domains such as attention, working memory, inhibition, etc. However, the neural mechanisms underlying this relationship, remains uncertain.

Objective

To perform a systematic review on exercise intervention studies that use event-related potentials (ERPs) as outcome for cognitive performance.

Methods

We identified studies through searches in four databases reporting the effects of either an acute bout or chronic exercise on any ERP associated with cognitive performance. Study population included participants >17 years of age with or without a diagnosis.

Results

A total of 5,797 records were initially identified through database searching of which 52 were eligible for inclusion. Most studies were of acute aerobic exercise with moderate intensity. Results were heterogenious across studies, but there was a trend that ERP amplitude increased and (to a lesser extent) latencies decreased post-exercise. The P3 ERP was the most often reported ERP.

Conclusion

Heterogeneity across studies regarding methodology limited the possibility to draw definitive conclusions but the most consistent findings were that acute aerobic exercise was associated with higher amplitudes, and to a lesser extent shorter latencies, of ERPs.

The Role of Brain-Derived Neurotrophic Factor Signaling in Central Nervous System Disease Pathogenesis

Recent studies have found abnormal levels of brain-derived neurotrophic factor (BDNF) in a variety of central nervous system (CNS) diseases (e.g., stroke, depression, anxiety, Alzheimer’s disease, and Parkinson’s disease). This suggests that BDNF may be involved in the pathogenesis of these diseases. Moreover, regulating BDNF signaling may represent a potential treatment for such diseases. With reference to recent research papers in related fields, this article reviews the production and regulation of BDNF in CNS and the role of BDNF signaling disorders in these diseases. A brief introduction of the clinical application status of BDNF is also provided.

Factors influencing participation in physical activity for persons living with dementia in rural and northern communities in Canada: a qualitative study

OBJECTIVE

In recognition that engagement in physical activities for persons living with dementia can be challenging in rural and northern communities, the objective of this study was to explore the factors influencing physical activity participation among persons living with dementia in rural/northern communities and to identify the locally-driven mitigation strategies participants used to address barriers to physical activity.

SETTING

Interviews and focus groups were conducted in two locations in northern British Columbia, Canada including a rural community (<10 000 persons) and a medium-sized geographically isolated city (<80 000 persons). Both communities are located at substantial distances (>700 km) from larger urban centres.

PARTICIPANTS

Twenty-nine individuals participated including healthcare providers (n=8), community exercise professionals (n=12), persons living with dementia (n=4) and care partners (n=5).

RESULTS

Rural and northern contextual factors including aspects of the built and natural environment were the main drivers of physical activity for persons living with dementia. Limited capacity in the health system to support physical activity due to a lack of referrals, poor communication mechanisms and limited resources for programming created challenges for physical activity participation. At the community level, local champions filled gaps in physical activity programming by leveraging informal networks to organise opportunities. Programme-level factors included a lack of consistency in staff, and challenges defining programme scope given limited population size and the fear of stigma for persons living with dementia.

CONCLUSIONS

Environmental context and limited access to specialised programming affect the opportunities for persons living with dementia to engage in physical activities. Rural and northern communities showed resiliency in providing physical activity opportunities yet remained fragile due to human resource challenges. Without reliable resources and sustained support from the health system, local champions remain vulnerable to burnout. Enhancing support for local champions may provide greater stability and support to physical activity promotion in rural and northern communities.

Lesions without symptoms: understanding resilience to Alzheimer disease neuropathological changes

Since the original description of amyloid-β plaques and tau tangles more than 100 years ago, these lesions have been considered the neuropathological hallmarks of Alzheimer disease (AD). The prevalence of plaques, tangles and dementia increases with age, and the lesions are considered to be causally related to the cognitive symptoms of AD. Current schemes for assessing AD lesion burden examine the distribution, abundance and characteristics of plaques and tangles at post mortem, yielding an estimate of the likelihood of cognitive impairment. Although this approach is highly predictive for most individuals, in some instances, a striking mismatch between lesions and symptoms can be observed. A small subset of individuals harbour a high burden of plaques and tangles at autopsy, which would be expected to have had devastating clinical consequences, but remain at their cognitive baseline, indicating 'resilience'. The study of these brains might provide the key to understanding the 'black box' between the accumulation of plaques and tangles and cognitive impairment, and show the way towards disease-modifying treatments for AD. In this Review, we begin by considering the heterogeneity of clinical manifestations associated with the presence of plaques and tangles, and then focus on insights derived from the rare yet informative individuals who display high amounts of amyloid and tau deposition in their brains (observed directly at autopsy) without manifesting dementia during life. The resilient response of these individuals to the gradual accumulation of plaques and tangles has potential implications for assessing an individual's risk of AD and for the development of interventions aimed at preserving cognition.

Association of Hand Grip Strength with Mild Cognitive Impairment in Middle-Aged and Older People in Guangzhou Biobank Cohort Study

Background: Lower hand grip strength has been linked to cognitive impairment, but studies in older Chinese are limited. We examined the association of hand grip strength with cognitive function in a large sample of older Chinese. Methods: 6806 participants aged 50+ years from the Guangzhou Biobank Cohort Study (GBCS) were included. Relative grip strength was calculated by absolute handgrip strength divided by the body mass index (BMI). Cognitive function was assessed using the Delayed Word Recall Test (DWRT, from 0 to 10) and the Mini Mental State Examination (MMSE, from 0 to 30), with higher scores indicating better cognition. Results: After adjusting for multiple potential confounders, lower absolute grip strength and relative grip strength were significantly associated with lower DWRT (all p < 0.05) in all participants. No significant interaction effects between sex and handgrip strength on cognitive impairment were found (p from 0.27 to 0.87). No significant association between handgrip strength and total MMSE scores was found in the total sample or by sex (p from 0.06 to 0.50). Regarding the individual components of MMSE, lower absolute and relative grip strength were significantly associated with lower scores of the recall memory performance in all participants (p from 0.003 to 0.04). Conclusion: We have shown for the first time a positive association of grip strength with recall memory performance, but not general cognitive function in older people, which warrants further investigation.

Lifestyle affects amyloid burden and cognition differently in men and women

Objective

Evidence on associations of lifestyle factors with Alzheimer's pathology and cognition are ambiguous, potentially because they rarely addressed inter‐relationships of factors and sex effects. While considering these aspects, we examined the relationships of lifestyle factors with brain amyloid burden and cognition.

Methods

We studied 178 cognitively normal individuals (women, 49%; 65.0 [7.6] years) and 54 individuals with mild cognitive impairment (women, 35%; 71.3 [8.3] years) enrolled in a prospective study of volunteers who completed ¹⁸F‐Flutemetamol amyloid positron emission tomography. Using structural equation modeling, we examined associations between latent constructs representing metabolic/vascular risk, physical activity, and cognitive activity with global amyloid burden and cognitive performance. Furthermore, we investigated the influence of sex in this model.

Results

Overall, higher cognitive activity was associated with better cognitive performance and higher physical activity was associated with lower amyloid burden. The latter association was weakened to a nonsignificant level after excluding multivariate outliers. Examination of the moderating effect of sex in the model revealed an inverse association of metabolic/vascular risk with cognition in men, whereas in women metabolic/vascular risk trended toward increased amyloid burden. Furthermore, a significant inverse association between physical activity and amyloid burden was found only in men. Inheritance of an APOE4 allele was associated with higher amyloid burden only in women.

Interpretation

Sex modifies effects of certain lifestyle‐related factors on amyloid burden and cognition. Notably, our results suggest that the negative impact of metabolic/vascular risk influences the risk of cognitive decline and Alzheimer's disease through distinct paths in women and men. ANN NEUROL 2022;92:451–463

Asymmetrical Handgrip Strength Is Associated with Lower Cognitive Performance in the Elderly

(1) Background: Several studies have reported that handgrip strength (HGS) may be a sign of lower cognitive performance. However, studies supporting an association between asymmetrical HGS and cognitive function are lacking. This study aimed to determine the association between asymmetrical HGS and cognitive performance among the elderly. (2) Methods: The study sample included 2729 individuals aged ≥60 years-old who participated in the 2011-2014 National Health and Nutrition Examination Survey. The cognitive tests consisted of the word learning and recall modules from the Consortium to Establish a Registry for Alzheimer's Disease (CERAD), Animal Fluency Test, and Digit Symbol Substitution Test (DSST). HGS was measured using a handgrip dynamometer, and asymmetrical HGS was used to calculate HGS. (3) Results: Of the 2729 participants, 53.0% were aged 60 to 69 years-old, and 47.0% were aged 70 years and older. All cognitive performance scores were significantly correlated with asymmetrical HGS in both age groups. After adjusting for confounders, there was a significant association between DSST and HGS asymmetry in both age groups. Contrastingly, a significant association was only observed for the relationship between the CERAD test and HGS asymmetry in the ≥70 year-old group. (4) Conclusions: We found that low cognitive function was associated with asymmetrical HGS in elderly participants in the United States. Thus, asymmetrical HGS may be an important predictor of cognitive deficits. However, further research is required to confirm our results and to establish possible mechanisms.

Unexpected Consequences of Noise-Induced Hearing Loss: Impaired Hippocampal Neurogenesis, Memory, and Stress

Noise-induced hearing loss (NIHL), caused by direct damage to the cochlea, reduces the flow of auditory information to the central nervous system, depriving higher order structures, such as the hippocampus with vital sensory information needed to carry out complex, higher order functions. Although the hippocampus lies outside the classical auditory pathway, it nevertheless receives acoustic information that influence its activity. Here we review recent results that illustrate how NIHL and other types of cochlear hearing loss disrupt hippocampal function. The hippocampus, which continues to generate new neurons (neurogenesis) in adulthood, plays an important role in spatial navigation, memory, and emotion. The hippocampus, which contains place cells that respond when a subject enters a specific location in the environment, integrates information from multiple sensory systems, including the auditory system, to develop cognitive spatial maps to aid in navigation. Acute exposure to intense noise disrupts the place-specific firing patterns of hippocampal neurons, “spatially disorienting” the cells for days. More traumatic sound exposures that result in permanent NIHL chronically suppresses cell proliferation and neurogenesis in the hippocampus; these structural changes are associated with long-term spatial memory deficits. Hippocampal neurons, which contain numerous glucocorticoid hormone receptors, are part of a complex feedback network connected to the hypothalamic-pituitary (HPA) axis. Chronic exposure to intense intermittent noise results in prolonged stress which can cause a persistent increase in corticosterone, a rodent stress hormone known to suppress neurogenesis. In contrast, a single intense noise exposure sufficient to cause permanent hearing loss produces only a transient increase in corticosterone hormone. Although basal corticosterone levels return to normal after the noise exposure, glucocorticoid receptors (GRs) in the hippocampus remain chronically elevated. Thus, NIHL disrupts negative feedback from the hippocampus to the HPA axis which regulates the release of corticosterone. Preclinical studies suggest that the noise-induced changes in hippocampal place cells, neurogenesis, spatial memory, and glucocorticoid receptors may be ameliorated by therapeutic interventions that reduce oxidative stress and inflammation. These experimental results may provide new insights on why hearing loss is a risk factor for cognitive decline and suggest methods for preventing this decline.

Cognitive training program improves cognitive ability and daily living ability in elderly patients with mild cognitive impairment

BACKGROUND

Mild cognitive impairment (MCI) is a clinical syndrome of mild memory or other cognitive impairment without dementia and is a clinical transition state between normal aging and dementia. Careful and meticulous nursing intervention can improve the clinical symptoms of MCI and delay the progression of the disease.

AIMS

This research aimed to evaluate the efficacy of cognitive function training interventions in elderly patients with MCI.

METHODS

106 patients were randomized into the intervention group or the control group. They received conventional nursing intervention and those in the intervention group received additional cognitive training program for 6 weeks. The Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), activities of daily living (ADL) scales, and Barthel index (BI) were evaluated before and 6 weeks after the intervention, as well as the serum levels of S100β and neuron-specific enolase (NSE) at two time points.

RESULTS

After intervention, the MMSE scores and MoCA scores in both groups were significantly increased and the score in the intervention group was significantly higher. In the intervention group, the performance of conventional nursing intervention and cognitive training program significantly increased the scores of ADL and BI (p < 0.001). The serum levels of NSE and S100β in the intervention group were significantly lower.

DISCUSSION

The performance of cognitive training program alleviated the brain tissue damage in elderly patients with MCI.

CONCLUSIONS

The performance of cognitive training program in elderly patients with MCI improved their cognitive ability and daily living ability.

Handgrip Strength and Cognitive Function among Elderly Koreans: Insights from the Korean Longitudinal Study of Ageing

This study aims to assess handgrip strength as a predictor of cognitive decline within men and women in Korea. A random-intercept logistic regression is fit to estimate the status changes in cognitive function throughout all rounds of the KLoSA, a nationally-representative survey of adults aged 45 years and older. Males in the highest quartile were 71.9% less likely to experience cognitive impairment than those in the lowest quartile. The odds of cognitive impairment for men in the third and second quartiles reduced by 62.6% and 60.4% respectively. Similarly, the odds of cognitive impairment for women declined as 72.7%, 63.0%, and 41.8% for fourth, third, and second quartile, respectively, compared with the lowest quartile. These results imply that assessing and monitoring handgrip strength may enable us to identify subgroups of the elderly with higher likelihood of cognitive impairment in Korea.

Effect of High Intensity Power Training on Cognitive Function in Older Adults with Type 2 Diabetes: Secondary Outcomes of the GREAT2DO Study

We sought to determine the effects of 12 months of power training on cognition, and whether improvements in body composition, muscle strength, and/or aerobic capacity (VO_2peak) were associated with improvements in cognition in older adults with type 2 diabetes (T2D). Participants with T2D were randomized to power training or low-intensity sham exercise control condition, 3 days per week for 12 months. Cognitive outcomes included memory, attention/speed, executive function, and global cognition. Other relevant outcomes included VO_2peak, strength, and whole body and regional body composition. One hundred and three adults with T2D (mean age 67.9 years; standard deviation [SD] 5.9; 50.5% women) were enrolled and analyzed. Unexpectedly, there was a nearly significant improvement in global cognition (p = .05) in the sham group relative to power training, although both groups improved over time (p < .01). There were significant interactions between group allocation and body composition or muscle strength in the models predicting cognitive changes. Therefore, after stratifying by group allocation, improvements in immediate memory were associated with increases in relative skeletal muscle mass (r = 0.38, p = .03), reductions in relative body fat (r = −0.40, p = .02), and increases in knee extension strength were directly related to changes in executive function (r = −0.41, p = .02) within the power training group. None of these relationships were present in the sham group (p > .05). Although power training did not significantly improve cognition compared to low-intensity exercise control, improvements in cognitive function in older adults were associated with hypothesized improvements in body composition and strength after power training.

Healthy Food Pyramid as Well as Physical and Mental Activity in the Prevention of Alzheimer’s Disease

The ageing of the population is resulting in neurodegenerative diseases, including Alzheimer’s disease (AD), which are an increasing social, economic and medical problem. Diet and physical activity are now considered as important modifiable factors that help prevent or delay the development of AD and other dementia-related diseases. The pyramid of healthy nutrition and lifestyle is a way of presenting the principles, the implementation of which gives a chance for proper development and a long healthy life. The basis of the pyramid, in the first place, is physical activity. Our review of the literature in the PubMed database supports the hypothesis that complementary factors, such as proper diet, physical exercise and mental activity, have a positive impact on the prevention of neurodegenerative diseases. The nutritional recommendations for healthy adults primarily include the consumption of vegetables, fruits, cereals, legumes, vegetable oils and fishes. Therefore, the introduction of Mediterranean and Asian diets may reduce the risk of the neurodegenerative diseases associated with dementia, whereas dairy products and meat—the main sources of L-carnitine—should be consumed in moderate amounts. The aim of our work is to provide up-to-date knowledge about the appropriate dietary model and healthy lifestyle elements and their impact on good health and the long life of people.

Low Risk of Dementia in Patients With Newly Diagnosed Atrial Fibrillation and a Clustering of Healthy Lifestyle Behaviors: A Nationwide Population-Based Cohort Study

Background Limited data are available on the clinical impact of healthy lifestyle behaviors on the risk of dementia in patients with new-onset atrial fibrillation (AF). Here, we aimed to evaluate the association between a combination of healthy lifestyle behaviors and the risk of incident dementia in patients with AF. Methods and Results Using the Korean National Health Insurance database between 2009 and 2016, we identified 199 952 adult patients who were newly diagnosed as AF without dementia. Patients were categorized into 4 groups by healthy lifestyle behavior score (HLS) with 1 point each being assigned for no current smoking, alcohol abstinence, and regular exercise. The HLS 0, 1, 2, and 3 groups included 4.4%, 17.4%, 53.4%, and 24.8% of the patients, respectively. We performed an inverse probability of treatment weighting to balance covariates between HLS groups. The HLS 1, 2, and 3 groups were associated with a lower risk of dementia compared with the HLS 0 group (hazard ratio [HR], 0.769; 95% CI, 0.704-0.842 for HLS 1; HR, 0.770; 95% CI, 0.709-0.836 for HLS 2; and HR, 0.622; 95% CI, 0.569-0.679 for HLS 3). The risk of dementia showed a tendency to decrease with an increase in HLS (P-for-trend <0.001). Conclusions A clustering of healthy lifestyle behaviors was associated with a significantly lower risk of dementia in patients with new-onset AF. These findings support the promotion of a healthy lifestyle within an integrated care approach to AF patient management.

Impact of Activity Tracker Usage in Combination with a Physical Activity Intervention on Physical and Cognitive Parameters in Healthy Adults Aged 60+: A Randomized Controlled Trial

Regular physical activity (PA) is of central importance for healthy aging and has a well-known impact on helping older adults maintain their cognitive and physical health. Thus, we aimed to compare the effectiveness of two physical activity interventions primarily conducted at home (print-based or web-based vs. web-based plus the use of an activity tracker) on cognitive and physical health parameters in older adults. Data of participants (n = 551, 60–80 years) were analyzed after being randomly allocated to a waitlist control group (CG), a web-based or print-based intervention group (IG) or a web-based intervention group that also included the use of an activity tracker (AG). Measured parameters were grip strength, endurance (two-minute step test), gait speed (four-meter walk test), cognition (Simon task; balanced integration score (BIS), reaction time and accuracy) and physical self-concept (Physical Self-Description Questionnaire (PSDQ)). We found the highest effect sizes in all measured dimensions for AG (grip strength, endurance, gait speed, reaction time, physical self-concept), followed by IG (endurance, gait speed, reaction time, physical self-concept) and CG (endurance, gait speed, BIS). Findings suggest that a combined web-based and activity tracker intervention may improve physical functions, physical self-concept, and cognition in community-dwelling older adults.

Physical activity as a protective factor for dementia and Alzheimer's disease: systematic review, meta-analysis and quality assessment of cohort and case-control studies

Objective

Physical activity (PA) is associated with a decreased incidence of dementia, but much of the evidence comes from short follow-ups prone to reverse causation. This meta-analysis investigates the effect of study length on the association.

Design

A systematic review and meta-analysis. Pooled effect sizes, dose–response analysis and funnel plots were used to synthesise the results.

Data sources

CINAHL (last search 19 October 2021), PsycInfo, Scopus, PubMed, Web of Science (21 October 2021) and SPORTDiscus (26 October 2021).

Eligibility criteria

Studies of adults with a prospective follow-up of at least 1 year, a valid cognitive measure or cohort in mid-life at baseline and an estimate of the association between baseline PA and follow-up all-cause dementia, Alzheimer’s disease or vascular dementia were included (n=58).

Results

PA was associated with a decreased risk of all-cause dementia (pooled relative risk 0.80, 95% CI 0.77 to 0.84, n=257 983), Alzheimer’s disease (0.86, 95% CI 0.80 to 0.93, n=128 261) and vascular dementia (0.79, 95% CI 0.66 to 0.95, n=33 870), even in longer follow-ups (≥20 years) for all-cause dementia and Alzheimer’s disease. Neither baseline age, follow-up length nor study quality significantly moderated the associations. Dose–response meta-analyses revealed significant linear, spline and quadratic trends within estimates for all-cause dementia incidence, but only a significant spline trend for Alzheimer’s disease. Funnel plots showed possible publication bias for all-cause dementia and Alzheimer’s disease.

Conclusion

PA was associated with lower incidence of all-cause dementia and Alzheimer’s disease, even in longer follow-ups, supporting PA as a modifiable protective lifestyle factor, even after reducing the effects of reverse causation.

Physical Activity Self-Report Is Not Reliable Among Subjects with Mild Vascular Cognitive Impairment: The AFIVASC Study

BACKGROUND

The World Health Organization (WHO) recommends a minimum of 150 minutes of moderate physical activity per week. Adherence to these recommendations is difficult to assess.

OBJECTIVE

We aimed to evaluate the validity of self-reported physical activity in mild vascular cognitive impairment (mVCI) and whether physical activity was associated with cognitive status, by using baseline data from a randomized controlled trial.

METHODS

A hundred and four subjects with mVCI were included (mean age 72 years; 51% women). Subjects underwent neurological, physical, and comprehensive neuropsychological assessments. Adherence to WHO physical activity recommendations was evaluated using both self-reported information and objective measures (accelerometry).

RESULTS

There was poor agreement (kappa = 0.106) between self-report of following WHO recommendations and actually fulfilling them according to accelerometry. Only 16.6% of participants reported following WHO recommendations and displayed compatible values according to the accelerometer. Participants whose accelerometry values confirmed adherence to WHO recommendations had better performance in a global measure of cognition, attention, and mental speed processing. In multiple regression analyses, education and accelerometry values in accordance with WHO recommendations were independently associated with the global measure of cognition, attention, and processing speed, controlling for sex, age, and depressive symptoms. Accelerometry results were not associated with memory and executive functions.

CONCLUSION

In this sample of mVCI subjects, self-reported physical activity displayed poor agreement with accelerometry values, suggesting that objective measures of physical activity are preferable. Physical activity (performed, at least, according to WHO recommendations) was associated with better cognitive performance overall.

Joint Hidden Markov Model for Longitudinal and Time-to-Event Data with Latent Variables

This study develops a new joint modeling approach to simultaneously analyze longitudinal and time-to-event data with latent variables. The proposed model consists of three components. The first component is a hidden Markov model for investigating a longitudinal observation process and its underlying transition process as well as their potential risk factors and dynamic heterogeneity. The second component is a factor analysis model for characterizing latent risk factors through multiple observed variables. The third component is a proportional hazards model for examining the effects of observed and latent risk factors on the hazards of interest. A shared random effect is introduced to allow the longitudinal and time-to-event outcomes to be correlated. A Bayesian approach coupled with efficient Markov chain Monte Carlo methods is developed to conduct statistical inference. The performance of the proposed method is evaluated through simulation studies. An application of the proposed model to a general health survey study concerning cognitive impairment and mortality for Chinese elders is presented.

Association Between Physical Activity and Risk of Disabling Dementia in Japan

IMPORTANCE

The associations of daily total physical activity and total moderate to vigorous physical activity (MVPA) with dementia are still unclear.

OBJECTIVE

To investigate the association between daily total physical activity and subsequent risk of disabling dementia in large-scale, extended follow-up prospective study.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study used data from questionnaires collected between 2000 and 2003 from 8 areas from the Japan Public Health Center-based Prospective Disabling Dementia Study. Participants included adults aged 50 to 79 years in with available follow-up data on disabling dementia. Data analysis was performed from February 1, 2019, to July 31, 2021.

EXPOSURES

Daily total physical activity, total MVPA, and leisure-time MVPA.

MAIN OUTCOMES AND MEASURES

The main outcome was incidence of disabling dementia during the dementia ascertainment period between 2006 and 2016, based on the national long-term care insurance system. Risks of dementia in association with daily total physical activity, total MVPA, and leisure time MVPA were calculated using multivariable adjusted hazard ratios (aHRs).

RESULTS

Among 43 896 participants (mean [SD] age, 61.0 [7.5] years; 23 659 [53.9%] women), 5010 participants were newly diagnosed with disabling dementia during a mean (SD) of 9.5 (2.8) years in the dementia ascertainment period. In the highest daily total physical activity group, compared with the lowest activity group, risk of dementia was lower in men (aHR, 0.75 [95% CI, 0.66-0.85]; P for trend < .001) and women (aHR, 0.75 [95% CI, 0.67-0.84]; P for trend < .001). Similar inverse associations were observed in men and women for total MVPA (men: aHR, 0.74 [95% CI, 0.65-0.84]; P for trend < .001; women: aHR, 0.74 [95% CI, 0.66-0.83]; P for trend < .001) and leisure-time MVPA (men: aHR, 0.59 [95% CI, 0.53-0.67]; P for trend < .001; women: aHR, 0.70 [95% CI, 0.63-0.78]; P for trend < .001). However, these inverse associations disappeared when participants diagnosed with disabling dementia within 7 years of the starting point were excluded in men (aHR, 0.93 [95%CI, 0.77-1.12]) and within 8 years were excluded in women (aHR, 0.86 [95%CI, 0.71-1.04]). The association remained significant among men in the highest vs lowest group of leisure-time MVPA, after excluding participants diagnosed within the first 9 years (aHR, 0.72 [95% CI, 0.56-0.92]; P for trend = .004).

CONCLUSIONS AND RELEVANCE

This cohort study examined associations of daily total physical activity and total MVPA with risk of disabling dementia. The findings suggest that a high level of leisure-time MVPA was associated with decreased risk of disabling dementia in men.

Prospective Associations between Physical Activity and Memory in the Canadian Longitudinal Study on Aging: Examining Social Determinants

Objectives

To examine associations between physical activity (PA) and prospectively assessed memory in a cohort of cognitively healthy adults, after accounting for understudied social determinants.

Methods

We used data from the Canadian Longitudinal Study on Aging (CLSA). PA (exposure) and memory (outcome) were assessed using validated measures in 2013–2015 and 2015–2018, respectively. Respondents reported their daily number of hours spent engaging in five different PAs. We conducted multiple imputation and used linear regression (n = 41,394), adjusting for five categories of covariates: demographics, sensory health characteristics, health behaviors, health status, and social determinants (sex/gender, education, income, social support, perceived social standing, race, and sexual orientation).

Results

In crude models, nearly every intensity and duration of PA was associated with better memory. In fully adjusted models, protective associations were attenuated; however, some associations held: all durations of walking, most durations of light activities, moderate activities for ≥1 hour, and strenuous activities for 1 to <2 hours.

Discussion

Some forms of PA may be associated with better memory. The benefits of higher intensity PA may only be realized after social determinants are addressed.

Association among cognitive function, physical fitness, and health status in older women

This study examined the association among cognitive function, physical fitness, and health status in healthy older women. Ninety-four females aged from 62 to 86 years (72.66±5.38 years) from community healthcare centers and an exercise club in Seoul, South Korea. Cognitive function was assessed using the Seoul Neuropsychological Screening Battery. Physical performance comprised cardiorespiratory endurance, lower extremity strength, active balance ability, and walking speed. Health status included blood pressure and waist circumference. Multiple linear regression analyses were performed to determine the relationship among cognitive function, fitness components, and health status, with age and educational attainment as covariates. In the unadjusted model, attention was significantly associated with cardiovascular endurance (B=0.19, P<0.05). Memory was significantly associated with lower limb strength (B=0.77, P<0.05) and active balance ability (B=2.35, P<0.05). In the adjusted model, attention was significantly associated with cardiovascular endurance (B=0.15, P<0.05). Memory was significantly associated with lower limb strength (B=0.87, P<0.05). In both models, cognitive function was not significantly associated with any health status variable. Though limited by a relatively small sample of female participants, who were healthy registrants of a community exercise program with normal cognitive function, the current study demonstrates that cognitive function is significantly associated with physical fitness, but not with health status, in healthy older women.

Exercise training improves memory and produces changes in the adrenal gland morphology in the experimental autoimmune encephalomyelitis

Objective. The present study sought to verify the effects of an exercise training on the memory along with the morphological assessment of the adrenal gland tissue in the rats with experimental autoimmune encephalomyelitis (EAE). Methods. Female Lewis rats were randomly divided into three groups: EAE group, EAE group with exercise (EAE+Ex), and control group (CO). Each group contained 10 rats. To evaluate the memory, all rats were subjected to the Morris water maze learning test for four consecutive days and one day for a prop test. EAE was induced by guinea pig spinal cord homogenate emulsified in incomplete Freund's adjuvant and heat-mycobacterium. The exercise training on a motorized treadmill was initiated 3 weeks before EAE induction and disconnected 2 weeks post-induction. Results. We found that exercise training for five weeks produced an improved swimming velocity related to memory improvement in EAE+Ex group in comparison with EAE group, but not an incurable adrenal gland tissue after EAE induction. Conclusions. The experimental design selected for this study appears to be an effective treatment for memory in rats with experimental autoimmune encephalomyelitis.

Physical activity ameliorates the function of organs via adipose tissue in metabolic diseases

Adipose tissue is a dynamic organ in the endocrine system that can connect organs by secreting molecules and bioactive. Hence, adipose tissue really plays a pivotal role in regulating metabolism, inflammation, energy homeostasis, and thermogenesis. Disruption of hub bioactive molecules secretion such as adipokines leads to dysregulate metabolic communication between adipose tissue and other organs in non-communicable disorders. Moreover, a sedentary lifestyle may be a risk factor for adipose tissue function. Physical inactivity leads to fat tissue accumulation and promotes obesity, Type 2 diabetes, cardiovascular disease, neurodegenerative disease, fatty liver, osteoporosis, and inflammatory bowel disease. On the other hand, physical activity may ameliorate and protect the body against metabolic disorders, triggering thermogenesis, metabolism, mitochondrial biogenesis, β-oxidation, and glucose uptake. Furthermore, physical activity provides an inter-organ association and cross-talk between different tissues by improving adipose tissue function, reprogramming gene expression, modulating molecules and bioactive factors. Also, physical activity decreases chronic inflammation, oxidative stress and improves metabolic features in adipose tissue. The current review focuses on the beneficial effect of physical activity on the cardiovascular, locomotor, digestive, and nervous systems. In addition, we visualize protein-protein interactions networks between hub proteins involved in dysregulating metabolic induced by adipose tissue.

Late-Life Physical Activities Moderate the Relationship of Amyloid-β Pathology with Neurodegeneration in Individuals Without Dementia

BACKGROUND

Physical activities (PA) have been suggested to reduce the risk of Alzheimer's disease (AD) dementia. However, information on the neuropathological links underlying the relationship is limited.

OBJECTIVE

We investigated the role of midlife and late-life PA with in vivo AD neuropathologies in old adults without dementia.

METHODS

This study included participants from the Korean Brain Aging Study for Early Diagnosis and Prediction of Alzheimer's disease (KBASE). The participants underwent comprehensive clinical and neuropsychological assessment, [11C] Pittsburgh Compound B positron emission tomography (PET), [18F] fluorodeoxyglucose PET, and magnetic resonance imaging. Using the multi-modal brain imaging data, in vivo AD pathologies including global amyloid deposition, AD-signature region cerebral glucose metabolism (AD-CM), and AD-signature region cortical thickness (AD-CT) were quantified. Both midlife and late-life PA of participants were measured using the Lifetime Total Physical Activity Questionnaire.

RESULTS

This study was performed on 260 participants without dementia (195 with normal cognitive function and 65 with mild cognitive impairment). PA of neither midlife nor late-life showed direct correspondence with any neuroimaging biomarker. However, late-life PA moderated the relationship of brain amyloid-β (Aβ) deposition with AD-CM and AD-CT. Aβ positivity had a significant negative effect on both AD-CM and AD-CT in individuals with lower late-life PA, but those with higher late-life PA did not show such results. Midlife PA did not have such a moderation effect.

CONCLUSION

The findings suggest that physically active lifestyle in late-life, rather than that in midlife, may delay AD-associated cognitive decline by decreasing Aβ-induced neurodegenerative changes in old adults.

The Moderating Role of Sleep Quality on the Association between Neuroticism and Frontal Executive Function in Older Adults

OBJECTIVE/BACKGROUND

Personality traits are regarded as risk factors for cognitive impairment in older adults, while sleep disturbance and physical inactivity are also considered as modifiable risk factors. Therefore, it could be beneficial to investigate the effects of those modifiable risk factors on the relationship between personality traits and cognitive functions, to prepare appropriate strategies for mitigating cognitive impairment.

PARTICIPANTS

A total of 155 cognitively unimpaired older adults were included.

METHODS

All participants underwent cognitive function tests using the Seoul Neuropsychological Screening Battery and examinations for personality traits using the Big Five Inventory. Individual physical activity and sleep quality were assessed using the International Physical Activity Questionnaire and Pittsburgh Sleep Quality Index, respectively. A hierarchical linear multiple regression analysis was performed to demonstrate the direct association between personality traits and cognitive functions, and the multiple moderator analysis was used to analyze the moderating effects of lifestyle factors on this association.

RESULTS

Among the five personality traits, only neuroticism was negatively associated with the frontal executive and visuospatial functions after controlling age, sex, and years of education. Interestingly, the negative relationship between neuroticism and frontal executive function was alleviated in older adults with higher sleep quality.

CONCLUSIONS

Our findings demonstrated that higher sleep quality has significant moderating effects on the negative association between neuroticism and frontal executive functions in older adults, which suggests intervention for improving sleep quality such as cognitive behavioral therapy can be considered in older adults who have personality traits associated with a high risk of cognitive impairment.

Healthy memory aging - the benefits of regular daily activities increase with age

As the number of older adults increases, so does the pressure on health care systems due to age-related disorders. Attempts to reduce cognitive decline have focused on individual interventions such as exercise or diet, with limited success. This study adopted a different approach by investigating the impact of combined daily activities on memory decline. We used data from the National Institute of Aging’s Health and Retirement Study to explore two new questions: does combining activities affect memory decline, and if yes, does this impact change across the lifespan? We created a new machine learning model using 33 daily activities and involving 3210 participants. Our results showed that the effect of combined activities on memory decline was stronger than any individual activity’s impact. Moreover, this effect increased with age, whereas the importance of historical factors such as education, and baseline memory decreased. The present findings point out the importance of selecting multiple, diverse activities for older adults as they age. These results could have a significant impact on aging health policies promoting new programs such as social prescribing.

Regular aerobic exercise is positively associated with hippocampal structure and function in young and middle-aged adults

Regular exercise has numerous benefits for brain health, including the structure and function of the hippocampus. The hippocampus plays a critical role in memory function, and is altered in a number of psychiatric disorders associated with memory impairments (e.g., depression and schizophrenia), as well as healthy aging. While many studies have focused on how regular exercise may improve hippocampal integrity in older individuals, less is known about these effects in young to middle-aged adults. Therefore, we assessed the associations of regular exercise and cardiorespiratory fitness with hippocampal structure and function in these age groups. We recruited 40 healthy young to middle-aged adults, comprised of two groups (n = 20) who self-reported either high or low levels of exercise, according to World Health Organization guidelines. We assessed cardiorespiratory fitness using a graded exercise test (VO₂ max) and hippocampal structure via manual tracing of T1-weighted magnetic resonance images. We also assessed hippocampal function using magnetic resonance spectroscopy to derive estimates of N-acetyl-aspartate concentration and hippocampal-dependent associative memory and pattern separation tasks. We observed evidence of increased N-acetyl-aspartate concentration and associative memory performance in individuals engaging in high levels of exercise. However, no differences in hippocampal volume or pattern separation capacity were observed between groups. Cardiorespiratory fitness was positively associated with left and right hippocampal volume and N-acetyl-aspartate concentration. However, no associations were observed between cardiorespiratory fitness and associative memory or pattern separation. Therefore, we provide evidence that higher levels of exercise and cardiorespiratory fitness are associated with improved hippocampal structure and function. Exercise may provide a low-risk, effective method of improving hippocampal integrity in an early-to-mid-life stage.

Exercise Dosage in Reducing the Risk of Dementia Development: Mode, Duration, and Intensity-A Narrative Review

Senile dementia, also known as dementia, is the mental deterioration which is associated with aging. It is characterized by a decrease in cognitive abilities, inability to concentrate, and especially the loss of higher cerebral cortex function, including memory, judgment, abstract thinking, and other loss of personality, even behavior changes. As a matter of fact, dementia is the deterioration of mental and intellectual functions caused by brain diseases in adults when they are mature, which affects the comprehensive performance of life and work ability. Most dementia cases are caused by Alzheimer’s disease (AD) and multiple infarct dementia (vascular dementia, multi-infarct dementia). Alzheimer’s disease is characterized by atrophy, shedding, and degenerative alterations in brain cells, and its occurrence is linked to age. The fraction of the population with dementia is smaller before the age of 65, and it increases after the age of 65. Since women live longer than men, the proportion of women with Alzheimer’s disease is higher. Multiple infarct dementia is caused by a cerebral infarction, which disrupts blood supply in multiple locations and impairs cerebral cortex function. Researchers worldwide are investigating ways to prevent Alzheimer’s disease; however, currently, there are no definitive answers for Alzheimer’s prevention. Even so, research has shown that we can take steps to reduce the risk of developing it. Prospective studies have found that even light to moderate physical activity can lower the risk of dementia and Alzheimer’s disease. Exercise has been proposed as a potential lifestyle intervention to help reduce the occurrence of dementia and Alzheimer’s disease. Various workout modes will be introduced based on various physical conditions. In general, frequent exercise for 6–8 weeks lessens the risk of dementia development.

Impaired Cognitive Function and Hippocampal Changes Following Chronic Diazepam Treatment in Middle-Aged Mice

Background: Gamma-aminobutyric acid (GABA) type A receptors are positively allosterically modulated by benzodiazepine binding, leading to a potentiated response to GABA. Diazepam (DZP, a benzodiazepine) is widely prescribed for anxiety, epileptic discharge, and insomnia, and is also used as a muscle relaxant and anti-convulsant. However, some adverse effects - such as tolerance, dependence, withdrawal effects, and impairments in cognition and learning - are elicited by the long-term use of DZP. Clinical studies have reported that chronic DZP treatment increases the risk of dementia in older adults. Furthermore, several studies have reported that chronic DZP administration may affect neuronal activity in the hippocampus, dendritic spine structure, and cognitive performance. However, the effects of chronic DZP administration on cognitive function in aged mice is not yet completely understood. Methods: A behavioral test, immunohistochemical analysis of neurogenic and apoptotic markers, dendritic spine density analysis, and long-term potentiation (LTP) assay of the hippocampal CA1 and CA3 were performed in both young (8 weeks old) and middle-aged (12 months old) mice to investigate the effects of chronic DZP administration on cognitive function. The chronic intraperitoneal administration of DZP was performed by implanting an osmotic minipump. To assess spatial learning and memory ability, the Morris water maze test was performed. Dendritic spines were visualized using Lucifer yellow injection into the soma of hippocampal neurons, and spine density was analyzed. Moreover, the effects of exercise on DZP-induced changes in spine density and LTP in the hippocampus were assessed. Results: Learning performance was impaired by chronic DZP administration in middle-aged mice but not in young mice. LTP was attenuated by DZP administration in the CA1 of young mice and the CA3 of middle-aged mice. The spine density of hippocampal neurons was decreased by chronic DZP administration in the CA1 of both young and middle-aged mice as well as in the CA3 of middle-aged mice. Neither neurogenesis nor apoptosis in the hippocampus was affected by chronic DZP administration. Conclusion: The results of this study suggest that the effects of chronic DZP are different between young and middle-aged mice. The chronic DZP-induced memory retrieval performance impairment in middle-aged mice can likely be attributed to decreased LTP and dendritic spine density in hippocampal neurons in the CA3. Notably, prophylactic exercise suppressed the adverse effects of chronic DZP on LTP and spine maintenance in middle-aged mice.

Nutrition and cognition across the lifetime: an overview on epigenetic mechanisms

The functioning of our brain depends on both genes and their interactions with environmental factors. The close link between genetics and environmental factors produces structural and functional cerebral changes early on in life. Understanding the weight of environmental factors in modulating neuroplasticity phenomena and cognitive functioning is relevant for potential interventions. Among these, nutrition plays a key role. In fact, the link between gut and brain (the gut-brain axis) is very close and begins in utero, since the Central Nervous System (CNS) and the Enteric Nervous System (ENS) originate from the same germ layer during the embryogenesis. Here, we investigate the epigenetic mechanisms induced by some nutrients on the cognitive functioning, which affect the cellular and molecular processes governing our cognitive functions. Furthermore, epigenetic phenomena can be positively affected by specific healthy nutrients from diet, with the possibility of preventing or modulating cognitive impairments. Specifically, we described the effects of several nutrients on diet-dependent epigenetic processes, in particular DNA methylation and histones post-translational modifications, and their potential role as therapeutic target, to describe how some forms of cognitive decline could be prevented or modulated from the early stages of life.

5 Years of Exercise Intervention Did Not Benefit Cognition Compared to the Physical Activity Guidelines in Older Adults, but Higher Cardiorespiratory Fitness Did. A Generation 100 Substudy

Background: Aerobic exercise is proposed to attenuate cognitive decline in aging. We investigated the effect of different aerobic exercise interventions and cardiorespiratory fitness (CRF) upon cognition throughout a 5-year exercise intervention in older adults.

Methods: 106 older adults (52 women, age 70-77 years) were randomized into high-intensity interval training (HIIT; ∼90% peak heart rate), moderate-intensity continuous training (MICT; ∼70% peak heart rate), or control for 5 years. The HIIT and MICT groups performed supervised training twice weekly, while the control group was asked to follow the national physical activity guidelines (30 min of physical activity/day). At baseline, 1-, 3-, and 5-year follow-up, participants partook in cognitive testing (spatial memory, verbal memory, pattern separation, processing speed, working memory, and planning ability), underwent clinical testing, and filled out health-related questionnaires. Linear mixed models were used to assess the effects of the exercise group and CRF (measured as peak and max oxygen uptake) on each cognitive test. The effects of changes in CRF on changes in each cognitive test score throughout the intervention were also assessed. The associations between baseline CRF and cognitive abilities at the follow-ups were investigated using linear regressions.

Results: There was no group-by-time interaction on the cognitive measures, and neither HIIT nor MICT participation was associated with better cognitive performance than control at any time point during the 5-year intervention. All groups increased their CRF similarly during the 1st year and subsequently declined back to baseline levels after 5 years. A higher CRF was associated with higher processing speed throughout the intervention while increasing CRF during the intervention was associated with better working memory and worse pattern separation. Higher CRF at baseline predicted consistently better processing speed and verbal memory performance.

Conclusion: In this first 5-year randomized controlled trial investigating the effects of HIIT, MICT, and physical activity according to national guidelines on cognition, we observed no effect of exercise intervention group on cognition when compared to following the national physical activity guidelines. Still, the results showed that higher CRF and increasing CRF benefited multiple, but not all, cognitive abilities in older adults.

Clinical Trial Registration:www.ClinicalTrials.gov, identifier [NCT01666340].

Metabolic determinants of Alzheimer's disease: A focus on thermoregulation

Alzheimer's disease (AD) is a complex age-related neurodegenerative disease, associated with central and peripheral metabolic anomalies, such as impaired glucose utilization and insulin resistance. These observations led to a considerable interest not only in lifestyle-related interventions, but also in repurposing insulin and other anti-diabetic drugs to prevent or treat dementia. Body temperature is the oldest known metabolic readout and mechanisms underlying its maintenance fail in the elderly, when the incidence of AD rises. This raises the possibility that an age-associated thermoregulatory deficit contributes to energy failure underlying AD pathogenesis. Brown adipose tissue (BAT) plays a central role in thermogenesis and maintenance of body temperature. In recent years, the modulation of BAT activity has been increasingly demonstrated to regulate energy expenditure, insulin sensitivity and glucose utilization, which could also provide benefits for AD. Here, we review the evidence linking thermoregulation, BAT and insulin-related metabolic defects with AD, and we propose mechanisms through which correcting thermoregulatory impairments could slow the progression and delay the onset of AD.

Cognitive impairment and depression after acute myocardial infarction: associations with ejection fraction and demographic characteristics

Cognitive impairment and depression are often associated with acute myocardial infarction, however, the risk factors for their occurrence after myocardial infarction are still unclear. To determine the effect of reduced ejection fraction and demographic characteristics on the occurrence of cognitive impairment and depression after myocardial infarction. In the prospective study, the final sample consisted of 82 patients. Based on the value of the ejection fraction, the patients were divided into those with a value of < 40% and those having a value of ≥ 40%. Demographic data (age, gender, education), and data on comorbidities, were collected from the patients' medical history. The instruments of studies were: Mini-mental test and Beck depression inventory. The occurrence of cognitive impairment and depression was not, to a significant degree, associated with the level of ejection fraction. In contrast, demographics have shown positive predictive effects. Among demographic characteristics, the age of the patient proved to be a significant predictor for the occurrence of cognitive impairment (p = 0.004). The probability of cognitive impairment increases 1.16 times for each year of life. Significant depression predictor was female gender (p = 0.014). The probability of depression was 3.5 times greater for female gender. Cognitive impairment after acute myocardial infarction is more common in older patients, and depression in more common in women.

Association of Physical Activity Level With Risk of Dementia in a Nationwide Cohort in Korea

IMPORTANCE

Current guidelines recommend 500 to 999 metabolic equivalent (MET)-minutes per week (MET-min/wk) of regular physical activity. However, evidence regarding the association between light-intensity physical activity (LPA) and dementia in older adults is inconsistent.

OBJECTIVE

To assess the association between physical activity and new-onset dementia, focusing on the dose-response association between physical activity and dementia and the association of LPA with the incidence of dementia.

DESIGN, SETTING, AND PARTICIPANTS

For this nationwide retrospective cohort study, we analyzed 62 286 participants aged 65 years or older without preexisting dementia who had available health checkup data from the Korean National Health Insurance Service database from January 2009 to December 2012. Participants were followed up until December 31, 2013, and data analysis was performed from July 2020 to January 2021.

EXPOSURES

Physical activity level was assessed using a standardized, self-reported questionnaire at baseline. Physical activity-related energy expenditure (in MET-min/wk) was calculated by summing the product of frequency, intensity, and duration.

MAIN OUTCOMES AND MEASURES

Incidence of dementia. Incidence rates were calculated by dividing the number of events by the person-time at risk (presented as the incidence per 1000 person-years). Hazard ratios (HRs) and 95% CIs for dementia were analyzed according to physical activity level. Competing risk regression was performed by using the Fine-Gray subdistribution hazard model, with mortality as the competing risk for dementia events. Multivariable regression models were constructed with adjustment for various patient characteristics. Incident dementia occurring 2 years after enrollment was assessed, and separate analyses included all follow-up periods. Restricted cubic spline curves were used to examine the association of continuous values of physical activity with dementia.

RESULTS

Among 62 286 participants, 60.4% were women, and the mean (SD) age was 73.2 (5.3) years. During a median follow-up of 42 months, 3757 participants (6.0%) developed dementia, and the overall incidence was 21.6 per 1000 person-years. Compared with inactive individuals (0 MET-min/wk), insufficiently active (1-499 MET-min/wk; mean, 284 MET-min/wk), active (500-999 MET-min/wk; mean, 675 MET-min/wk), and highly active participants (≥1000 MET-min/wk; mean, 1627 MET-min/wk) showed 10% (adjusted hazard ratio [HR], 0.90; 95% CI, 0.81-0.99), 20% (adjusted HR, 0.80; 95% CI, 0.71-0.92), and 28% (adjusted HR, 0.72; 95% CI, 0.60-0.83) reduced dementia risk, respectively. Thus, a progressive decrease in the adjusted HR of dementia was associated with increasing physical activity level, and a restricted cubic spline curve showed that this association started with a low amount of total physical activity. This association was consistent regardless of age, sex, and other comorbidities or after censoring for stroke. Compared with total sedentary behavior, even a low amount of LPA (1-299 MET-min/wk; mean, 189 MET-min/wk) was associated with reduced dementia risk (adjusted HR, 0.86; 95% CI, 0.74-0.99).

CONCLUSIONS AND RELEVANCE

In older adults, an increased physical activity level, including a low amount of LPA, was associated with a reduced risk of dementia. Promotion of LPA might reduce the risk of dementia in older adults.

Traditional Thai exercise (Ruesi Dadton) for improving motor and cognitive functions in mild cognitive impairment: a randomized controlled trial

This study determined the effectiveness of a 12-week cycle of Ruesi Dadton (RSD) among older adults with mild cognitive impairment (MCI), for improving cognitive and physical performance. Seventy-six participants were included and were divided equally into two groups. A group performed RSD exercise for 60 min, 3 times/wk for 12 weeks, and the control group did not perform RSD exercise. The primary endpoint was cognitive function, as assessed by the Montreal cognitive assessment (MoCA), Mini-Mental State Examination, verbal fluency (VF) test, and trail making test parts A and B (TMT-A and TMT-B). The secondary endpoints were the Timed Up and Go (TUG) test, handgrip, and gait speed results, which were used to evaluate the physical function. There were significant differences in the TMT-B and handgrip scores (P<0.05) between the two groups. Both groups had improved MoCA scores (P<0.05) and normal walking speeds (P<0.01). Additionally, the RSD group showed improved VF test (P<0.01), TMT-B (P<0.01), and TUG test (P<0.05); a negative correlation was found between MoCA and TUG test (P<0.05). However, high walking speed and handgrip (P<0.05) worsened in the control group. RSD exercise resulted in relevant improvements in the cognitive and physical functions in MCI.

Physical Work and Exercise Reduce the Risk of Cognitive Impairment in Older Adults: A Population-based Longitudinal Study

BACKGROUND

The independent effect of physical work on the risk of cognitive impairment in older Chinese older adults living in rural areas remains to be elucidated.

OBJECTIVE

We aimed to determine whether physical work and physical exercise can reduce the risk of cognitive impairment.

METHODS

We collected data from 7,000 permanent residents without cognitive impairment (age ≥60 years) over a follow-up period of 2 years. We used the Chinese version of the Mini-Mental State Examination (MMSE) to assess cognitive function. We performed multivariate Cox regression analyses to calculate adjusted Hazard Ratios (HRs) and 95% Confidence Intervals (%95 CIs) as measures of the association between physical work/exercise and cognitive impairment while controlling for potential confounders.

RESULTS

Over a median follow-up period of 1.93 years, 1,224 (17.5%) of 7,000 participants developed cognitive impairment, with a total incidence of 97.69 per 1,000 person-years. After adjustment for potential confounders, participating in physical work (HR: 0.51; 95% CI: 0.43-0.60) or physical exercise (HR: 0.53; 95% CI: 0.44-0.65) was associated with a reduced risk of cognitive impairment. Stratified analyses suggested additive and multiplicative interactions between physical work and exercise. Agricultural work (HR: 0.46; 95% CI: 0.38-0.55), walking/tai chi (HR: 0.54; 95% CI: 0.44-0.67), and brisk walking/yangko (HR: 0.57; 95% CI: 0.33-0.97) exerted significant protective effects against cognitive impairment.

CONCLUSION

Both physical work and exercise can reduce the risk of cognitive impairment in older adults. Reasonable types and appropriate intensities of physical activity are recommended to prevent or delay the progression of cognitive impairment.

The Role of Spirituality in Conceptualizations of Health Maintenance and Healthy Aging Among Latin American Immigrants

OBJECTIVES

We aimed to investigate ways in which spirituality was conceptualized in relationship to maintaining brain health and healthy aging in a cohort of older adults who immigrated to the United States from diverse regions of Latin America, in order to ultimately develop culturally-tailored brain health promotion approaches.

DESIGN

We conducted a qualitative study using semi-structured interviews.

SETTING

Participants were recruited from community centers and by a memory care center at a large academic medical center.

PARTICIPANTS

We interviewed 30 Spanish-speaking immigrants over age 60. Questions addressed perspectives about the brain, aging, and dementia. Interviews were coded for themes.

MEASUREMENTS

Thematic analysis was used to analyze participants' responses.

RESULTS

We identified 5 themes: (1) expressing gratitude to God for mental and physical health, (2) putting the onus of life and death in God's hands, (3) using church as a place to socialize and build community as an approach to leading a healthy lifestyle, (4) using prayer as nourishment for the soul and the brain, and (5) gaining inner-peace and calm, and thus maintaining a healthy life, due to a connection with God.

CONCLUSION

The incorporation of customized spiritual interventions may be a mechanism by which to increase the effectiveness of brain health promotion efforts.

Development and validation of new screening tool for predicting dementia risk in community-dwelling older Japanese adults

Background

Established clinical assessments for detecting dementia risk often require time, cost, and face-to-face meetings. We aimed to develop a Simplified Telephone Assessment for Dementia risk (STAD) (a new screening tool utilizing telephonic interviews to predict dementia risk) and examine the predictive validity of the STAD for the incidence of dementia.

Methods

We developed STAD based on a combination of literature review, statistical analysis, and expert opinion. We selected 12 binary questions on subjective cognitive complaints, depressive symptoms, and lifestyle activities. In the validation study, we used STAD for 4298 community-dwelling older adults and observed the incidence of dementia during the 24-month follow-up period. The total score of STAD ranging from 0 to 12 was calculated, and the cut-off point for dementia incidence was determined using the Youden index. The survival rate of dementia incidence according to the cut-off points was determined. Furthermore, we used a decision-tree model (classification and regression tree, CART) to enhance the predictive ability of STAD for dementia risk screening.

Results

The cut-off point of STAD was set at 4/5. Participants scoring ≥ 5 points showed a significantly higher risk of dementia than those scoring ≤ 4 points, even after adjusting for covariates (hazard ratio [95% confidence interval], 2.67 [1.40–5.08]). A decision tree model using the CART algorithm was constructed using 12 nodes with three STAD items. It showed better performance for dementia prediction in terms of accuracy and specificity as compared to the logistic regression model, although its sensitivity was worse than the logistic regression model.

Conclusions

We developed a 12-item questionnaire, STAD, as a screening tool to predict dementia risk utilizing telephonic interviews and confirmed its predictive validity. Our findings might provide useful information for early screening of dementia risk and enable bridging between community and clinical settings. Additionally, STAD could be employed without face-to-face meetings in a short time; therefore, it may be a suitable screening tool for community-dwelling older adults who have negative attitudes toward clinical examination or are non-adherent to follow-up assessments in clinical trials.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-03121-9.

Association of Dietary Patterns With Cognitive Function and Cognitive Decline in Sydney Memory and Ageing Study: A Longitudinal Analysis

BACKGROUND

The relationship of dietary patterns to cognitive health in older adults has attracted much research attention. However, results from existing studies are inconclusive.

OBJECTIVE

The aim of this study was to investigate the association between dietary patterns and overall cognitive performance and cognitive change over time.

DESIGN

This analysis was conducted as part of the longitudinal Sydney Memory and Ageing study with 6 years' follow-up. Mediterranean diet and Dietary Approaches to Stop Hypertension diet scores were generated based on dietary intake for each individual, assessed by the Dietary Questionnaire for Epidemiological Studies Version 2.

PARTICIPANTS/SETTING

This longitudinal study comprised 1037 community dwelling nondemented participants aged 70 to 90 years at baseline (September 2005 to December 2007), recruited from Sydney, Australia.

MAIN OUTCOME MEASURES

Neuropsychological tests assessed global cognition and 6 cognitive domains on 4 occasions, at baseline and 2, 4, and 6 years later.

STATISTICAL ANALYSES PERFORMED

Linear mixed-model analyses were conducted to examine the relationship between dietary scores, food components, and overall cognitive function and cognitive change over 6 years.

RESULTS

No associations of Mediterranean or Dietary Approaches to Stop Hypertension dietary scores with overall cognition and cognitive decline over 6 years were found. Higher intake of legumes and nuts was related to better overall performance in global cognition (β = .091; 95% CI: 0.035-0.146; P = .001) and to multiple cognitive domains and to less decline in global cognition (β = -.016; 95% CI: -0.032 to -0.001; P = .032).

CONCLUSION

Study findings suggest that greater consumption of legumes and nuts may be important to slow cognitive decline with age.

Cognitive effectiveness of high-intensity interval training for individuals with methamphetamine dependence: a study protocol for randomised controlled trial

INTRODUCTION

Cognitive deficit is a common syndrome of methamphetamine (MA) dependence. It is related to decision-making, control ability, and social functioning. High-intensity interval training (HIIT) is a training technique that requires people to work out at full intensity during a short period. Many studies have already shown the potential effects of HIIT on cognitive functions. The purpose of this trial is to evaluate the cognitive effects of HIIT on individuals with MA dependence.

METHODS AND ANALYSIS

A total of 240 individuals with MA dependence will be randomly assigned to the HIIT group, moderate-intensity continuous training (MICT) group and control (CON) group. HIIT will consist of a 24-min HIIT exercise on a treadmill. MICT will consist of a 1-h body-mind exercise. CON will be their traditional intervention. The experimental period will be 12 months with 3 interventions weekly for the first 6 months and follow-up for the next 6 months. All subjects will be given cognitive tests at baseline, after intervention and at follow-up. Cognitive performances will be compared by a mixed-model analysis for repeated measures.

DISCUSSION

HIIT training may reduce illicit drug cravings amongst individuals with MA dependence; hence, HIIT may have a good effect on the cognitive functions, such as memory and executive function, of individuals with MA dependence.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2000032492 . Registered on April 30, 2020 ( http://www.chictr.org.cn/edit.aspx?pid=52127&htm=4 ).

Association between social participation and cognitive function among middle- and old-aged Chinese: A fixed-effects analysis

Background

Social Participation (SP) is known to benefit cognitive function. However, whether the positive relationship holds across different types of SP and dimensions of cognitive function, and whether the statement stays true in middle- and old-aged Chinese have not been investigated. The present study aimed to understand the current patterns of SP and cognitive function in China’s context, and therefore, explore the associations between cognitive function and SP at different levels from various aspects.

Methods

A total of 7973 community residents aged 45 years and older were selected from the China Health and Retirement Longitudinal Study (CHARLS, 2011-2015). A fixed-effects analysis was used to explore the association between changes in SP (diversity, frequency, and type) and that in cognitive function (memory and mental status) over a four-year period.

Results

Changing from no SP to more variety (β = 0.377, 95% confidence interval (CI) = 0.192-0.562 for 1 type, β = 0.703, 95% CI = 0.470-0.937 for ≥2 types) or higher frequency (β = 0.235, 95% CI = 0.007-0.462 for not regularly, β = 0.604, 95% CI = 0.411-0.798) of SP was associated with improvements in cognitive function. Playing mah-jong and using Internet were associated with improved memory but not with mental status. Sports and volunteering were associated with improved mental status but not with memory. The same pattern was observed in men and in women.

Conclusions

The study confirmed that more diversity and higher frequency of SP was associated with improved cognitive function, whereas reminded policymakers to consider cultural context when developing target strategies to improve cognitive function.

Comparison of Subjective and Objective Methods to Measure the Physical Activity of Non-Depressed Middle-Aged Healthy Subjects with Normal Cognitive Function and Mild Cognitive Impairment-A Cross-Sectional Study

This study compared subjective and objective methods of measuring different categories of physical activity in non-depressed middle-aged subjects with normal cognitive function (NCF) and mild cognitive impairment (MCI). In total, 75 participants (NCF: n = 48, MCI: n = 27) were recruited and physical activity was assessed for seven days using the ActiGraph and the International Physical Activity Questionnaire (IPAQ). Anthropometric parameters, body compositions, resting metabolic rate, and energy expenditure were also assessed. ActiGraph data indicated that subjects with NCF were more active than MCI subjects. A comparison of the IPAQ and the ActiGraph data revealed a significant correlation between these methods for total (r = 0.3315, p < 0.01) and moderate (r = 0.3896, p < 0.01) physical activity in the total population and moderate activity (r = 0.2893, p < 0.05) within the NCF group. No associations between these methods were found within the MCI group. Independent predictors of subjectively evaluated total physical activity were alcohol consumption (p = 0.0358) and socio-professional status (p = 0.0288), while weight (p = 0.0285) and the Montreal Cognitive Assessment results (p = 0.0309) were independent predictors of objectively measured physical activity. In conclusion, the long version of IPAQ is a more reliable tool to assess PA in subjects with NCF than those with MCI. More studies are needed to confirm this finding.

Lack of physical activity, neuropsychiatric symptoms and the risk of incident mild cognitive impairment in older community-dwelling individuals

The present study examined the longitudinal association and interaction between lack of engaging in physical activity (PA) and presence of neuropsychiatric symptoms (NPS) with the risk of incident mild cognitive impairment (MCI). The authors conducted a prospective cohort study in the setting of the population-based Mayo Clinic Study of Aging in Minnesota, USA, involving 3083 cognitively unimpaired persons aged ≥ 50 years (1570 males; median age, 74 years). Predictors included: lack of engaging in light, moderate, and vigorous intensity PA within 1 year of baseline assessment as measured by a self-reported questionnaire; and presence of NPS (agitation, anxiety, apathy, appetite change, sleep/nighttime disturbance, depression, irritability, clinical depression, clinical anxiety) as measured by standardized tools. When the authors detected a statistically significant interaction, they compared the risk of incident MCI between four groups of participants (no NPS/engaging in PA = reference group; NPS/engaging in PA; no NPS/not engaging in PA; NPS/not engaging in PA) by calculating hazard ratios (HR) and 95% confidence intervals (CI) using Cox proportional hazard models adjusted for age (as time scale), sex, education, global cognition, medical comorbidities, and apolipoprotein E ɛ4 status. After a median follow-up of 6.3 years, 599 participants developed incident MCI. Not engaging in vigorous intensity PA and having sleep/nighttime disturbance (HR [95% CI], 1.61 [1.07, 2.43]; p = 0.021), clinical depression (1.98 [1.34, 2.92]; p < 0.001) or clinical anxiety (1.63 [1.11, 2.41]; p = 0.013) was associated with an increased risk of incident MCI as compared to the reference group. Thus, the combined presence of lack of vigorous intensity physical activity with sleep/nighttime disturbance behavior, clinical depression, or clinical anxiety was greater than the expected arithmetic sum of their independent effects. Neuropsychiatric symptoms appear to be a stronger driving force of incident MCI than lack of physical activity.

Daily steps and healthcare costs in Japanese communities

Physical inactivity is a pandemic that requires intensive, usually costly efforts for risk reduction of related chronic diseases. Nevertheless, it is challenging to determine the effectiveness of physical activity in healthcare cost reduction based on existing literature. Therefore, this study aimed to investigate the impact of physical activity (daily steps) on healthcare costs utilising the data retrieved from a health promotion project (the e-wellness Project, held in three municipalities in Japan). Evaluating the effects of daily steps, measured by pedometers, on healthcare costs by a quasi-experimental approach among participants aged 40–75 years (about 4000 person-years of observation, between 2009 and 2013), we found that a one-step-increase in the annual average daily step reduced outpatient healthcare costs by 16.26 JPY (≒ 0.11 GBD) in the short run. Based on the assumption of a dynamic relationship between the health statuses in multiple years, the long-run effects of daily steps on healthcare costs were estimated at 28.24 JPY (≒ 0.20 GBD). We determined the health benefits of walking in a sample of middle-aged and older Japanese adults by our findings that an increase in step counts reduced healthcare costs.

The Association between Physical Activity and Selected Parameters of Psychological Status and Dementia in Older Women

Physical activity has an unquestionable impact on broadly understood human health. One interesting issue related to this is the importance of movement on mental health and cognitive functioning. Research shows that regular physical activity improves the cognitive functioning of adults and people with mental disorders. Regular physical activity can be an important and powerful protective factor in cognitive impairment and dementia in the elderly, and exercise is an important non-pharmacological treatment for mild cognitive impairment or neurodegenerative diseases. This study aims to present the impact of physical activity on selected cognitive functions in physically active women over 60 years of age. The research was carried out in a group of 110 generally healthy women from the area of western Poland over 60 years of age, who were divided into four groups based on the intensity of their physical activity. A pedometer (sport watch) and a physical activity diary were used to measure physical activity. Body Mass Index was assessed. Selected cognitive functions were assessed using the MMSE test, motor and psychomotor skills were measured, and Luria's auditory memory test and recall test, a clock drawing test, and a GDS test were performed. There were statistically significant relationships between the level of physical activity and the effectiveness of cognitive processes. These results show that about 5000 steps a day is enough to see a positive effect on the mental health and cognitive functioning of this group of the elderly population. The women had an average BMI of 28.1 ± 4.7. BMI, indicating an overweight condition (over 30 kg/m2), was observed in 31% of women. The results of this study lead the authors to conclude that physical activity positively influences cognitive function and can be recommended for all seniors who do not have other serious comorbidities that would prevent them from playing sports.