Physical Activity: A Viable Way to Reduce the Risks of Mild Cognitive Impairment, Alzheimer's Disease, and Vascular Dementia in Older Adults

Navβ2 Intracellular Fragments Contribute to Aβ1-42-Induced Cognitive Impairment and Synaptic Deficit Through Transcriptional Suppression of BDNF

A pathological hallmark of Alzheimer's disease (AD) is the region-specific accumulation of the amyloid-beta protein (Aβ), which triggers aberrant neuronal excitability, synaptic impairment, and progressive cognitive decline. Previous works have demonstrated that Aβ pathology induced aberrant elevation in the levels and excessive enzymatic hydrolysis of voltage-gated sodium channel type 2 beta subunit (Navβ2) in the brain of AD models, accompanied by alteration in excitability of hippocampal neurons, synaptic deficits, and subsequently, cognitive dysfunction. However, the mechanism is unclear. In this research, by employing cell models treated with toxic Aβ1-42 and AD mice, the possible effects and potential mechanisms induced by Navβ2. The results reveal that Aβ1-42 induces remarkable increases in Navβ2 intracellular domain (Navβ2-ICD) and decreases in both BDNF exons and protein levels, as well as phosphorylated tropomyosin-related kinase B (pTrkB) expression in cells and mice, coupled with cognitive impairments, synaptic deficits, and aberrant neuronal excitability. Administration with exogenous Navβ2-ICD further enhances these effects induced by Aβ1-42, while interfering the generation of Navβ2-ICD and/or complementing BDNF neutralize the Navβ2-ICD-conducted effects. Luciferase reporter assay verifies that Navβ2-ICD regulates BDNF transcription and expression by targeting its promoter. Collectively, our findings partially elucidate that abnormal enzymatic hydrolysis of Navβ2 induced by Aβ1-42-associated AD pathology leads to intracellular Navβ2-ICD overload, which may responsible to abnormal neuronal excitability, synaptic deficit, and cognition dysfunction, through its transcriptional suppression on BDNF. Therefore, this work supplies novel evidences that Navβ2 plays crucial roles in the occurrence and progression of cognitive impairment of AD by transcriptional regulatory activity of its cleaved ICD.

Effectiveness of Simultaneous Combined Intervention for Enhancing Cognitive Function in Patients with Moderate Alzheimer's Disease

Background

The evidence supporting the effectiveness of combined interventions in Alzheimer's disease (AD) patients remains inconclusive.

Objective

The aim of this study was to evaluate the mid- and long-term effectiveness of physical training, alone or combined with cognitive games, on cognitive performance in patients with moderate AD.

Methods

Seventy-nine AD patients (≈73% females, age of ≈70±1 years) were randomly divided into three groups: aerobic-based training (AT-group, n = 27), aerobic-based training plus cognitive games (ACT-group, n = 25), and a control group engaged in reading (CG, n = 26), two sessions per week. Cognitive performance was evaluated at the start, 4th week (W4), end of the 8th week (W8), and after a 4-week detraining period (W12), using problem-solving (Tower-of-Hanoi), selective attention (Stroop-test), and working memory (Digit-Span-test) assessments. Stress levels and quality of life were also evaluated.Results:: Aerobic and combined training induced a positive effect on all cognitive functions tested at W4 (except problem-solving) and W8 (all p < 0.001) with greater improvements in working-memory and problem-solving in ACT-group (p < 0.05). Depression levels also decreased significantly, and quality of life improved at W8 (p < 0.001) in both groups. After 4 weeks of detraining, the beneficial effect of AT and ACT was still observed. The CG did not show any significant improvements at all time points.Conclusions:: Physical and cognitive interventions appear effective for improving cognitive-functions, quality-of-life, and reducing depression in AD patients. Combined training emerges as a more effective strategy to mitigate AD progression. Further research is necessary to validate these results and explore their potential for preventing early cognitive decline.

The effects of different exercise types on cognitive and physical functions in dementia patients: A randomized comparative study

PURPOSE

The physical and cognitive effects of aerobic exercise on dementia have been extensively studied. Further investigation of other types of exercise with different physiological effects is still needed. This study aimed to determine cognitive and physical effects of 6-week aerobic, balance, and combined (aerobic-balance) exercise programs on dementia.

MATERIALS AND METHODS

A total of 31 mild to moderate dementia patients aged 65-90 years were divided into three exercise groups. Before and after the 6-week exercise program, mental rotation, spatial orientation, visual memory, and mental status were assessed for cognitive functions, while fall risk, reaction time, lower limb strength, and frailty were assessed for physical functions. Comprehensive cognitive and physical assessments were performed to provide a holistic approach to dementia.

RESULTS

When post-exercise values were compared with pre-exercise values, only frailty decreased significantly in the aerobic exercise group (p = 0.017). After exercise program in balance and combined exercise groups, mental rotation (p = 0.005, p = 0.032), spatial orientation (p = 0.020, p = 0.035), mental status (p = 0.007, p = 0.014), and lower extremity strength (p = 0. 010, p = 0.005) increased significantly, while fall risk (p = 0.005, p = 0.005), reaction time (p = 0.028, p = 0.016), and frailty (p = 0.020, p = 0.009) decreased significantly. Moreover, in contrast to combined and aerobic exercise, improvement in visual memory was also observed in the balance exercise group (p = 0.016).

CONCLUSIONS

These findings suggest that balance and combined exercises may have broader effects on dementia than aerobic exercise. It emphasizes the importance of designing exercise programs for dementia patients, considering the cognitive and physical deficits of the patients, and creating a multidimensional treatment approach.

Treadmill exercise pretreatment ameliorated structural synaptic plasticity impairments of medial prefrontal cortex in vascular dementia rat and improved recognition memory

This study aimed to investigate structural synaptic plasticity in the medial prefrontal cortex of rats under treadmill exercise pretreatment or naive conditions in a vascular dementia model, followed by recognition memory performance in a novel object recognition task. In this study, 24 Sprague-Dawley rats were obtained and randomly assigned into 4 groups as follows: control group (Con group, n = 6), vascular dementia (VD group, n = 6), exercise and vascular dementia group (Exe + VD group, n = 6), and exercise group (Exe group, n = 6). Initially, 4 weeks of treadmill exercise intervention was administered to the rats in the Exe + VD and Exe groups. Then, to establish the vascular dementia model, the rats both in the VD and Exe + VD groups were subjected to bilateral common carotids arteries surgery. One week later, open-field task and novel recognition memory task were adopted to evaluate anxiety-like behavior and recognition memory in each group. Then, immunofluorescence and Golgi staining were used to evaluate neuronal number and spine density in the rat medial prefrontal cortex. Transmission electron microscopy was used to observe the synaptic ultrastructure. Finally, microdialysis coupled with high-performance liquid chromatography was used to assess the levels of 5-HT and dopamine in the medial prefrontal cortex. The behavior results showed that 4 weeks of treadmill exercise pretreatment significantly alleviated recognition memory impairment and anxiety-like behavior in VD rats (P < 0.01), while the rats in VD group exhibited impaired recognition memory and anxiety-like behavior when compared with the Con group (P < 0.001). Additionally, NeuN immunostaining results revealed a significant decrease of NeuN-marked neuron in the VD group compared to Con group (P < 0.01), but a significantly increase in this molecular marker was found in the Exe + VD group compared to the Con group (P < 0.01). Golgi staining results showed that the medial prefrontal cortex neurons in the VD group displayed fewer dendritic spines than those in the Con group (P < 0.01), and there were more spines on the dendrites of medial prefrontal cortex cells in Exe + VD rats than in VD rats (P < 0.01). Transmission electron microscopy further revealed that there was a significant reduction of synapses intensity in the medial prefrontal cortex of rats in the VD group when compared with the Con group(P < 0.01), but physical exercise was found to significantly increased synapses intensity in the VD model (P < 0.01). Lastly, the levels of dopamine and 5-HT in the medial prefrontal cortex of rats in the VD group was significantly lower compared to the Con group (P < 0.01), and treadmill exercise was shown to significantly increased the levels of dopamine and 5-HT in the VD rats (P < 0.05). Treadmill exercise pretreatment ameliorated structural synaptic plasticity impairments of medial prefrontal cortex in VD rat and improved recognition memory.

Wearable Activity Trackers That Motivate Women to Increase Physical Activity: Mixed Methods Study

BACKGROUND

Physical inactivity is a significant public health concern, particularly among women in the United States. Wearable activity trackers (WATs) have been proposed as a potential solution to increase awareness of and engagement in physical activity (PA). However, to be effective, WATs must include features and designs that encourage daily use.

OBJECTIVE

This study aims to explore the features and designs of WATs that appeal to women and determine whether devices with these attributes are effective motivators for women to be physically active.

METHODS

A mixed methods study guided by the self-determination theory was conducted among 15 women. Participants trialed 3 WATs with influence in their respective accessory domains: Apple Watch for the wrist; Oura Ring for the finger; and Bellabeat Leaf Urban for multiple sites (it can be worn as a bracelet, necklace, or clip). Participants documented their daily PA levels and rated their satisfaction with each device's comfort, features, and motivational effect. Focus groups were also conducted to gather additional feedback and experiences within the a priori areas of comfort, features, and motivation.

RESULTS

Behavioral Regulation in Exercise Questionnaire-2 scores indicated that most participants (14/15, 93%) were motivated at baseline (amotivation score: mean 0.13, SD 0.45), but on average, participants did not meet the national minimum PA guidelines according to the self-reported Physical Activity Vital Sign questionnaire (moderate to vigorous PA score: mean 144, SD 97.5 min/wk). Mean WAT wear time was 16.9 (SD 4.4) hours, 19.4 (SD 5.3) hours, and 20.4 (SD 4.7) hours for Apple Watch, Bellabeat Leaf Urban, and Oura Ring, respectively. During focus groups, participants reinforced their quantitative ratings and rankings of the WATs based on personal experiences. Participants shared a variety of both activity-related and non-activity-related features that they look for in a motivating device. When considering what the ideal WAT would be for a woman, participants suggested features of (1) comfort, (2) extended battery life, (3) durability, (4) immediate PA feedback, (5) intuitive PA sensing, and (6) programmability.

CONCLUSIONS

This study is the first to specifically address women's experiences with and preferences for different types of WATs. Those who work with women should realize how they view WATs and the role they play in motivation to be active.

Online Chair Yoga and Digital Learning for Rural Underserved Older Adults at Risk for Alzheimer's Disease and Related Dementias

OBJECTIVES

We evaluated the feasibility and preliminary efficacy of a home-based online chair yoga (OCY) program for racially and ethnically diverse rural community-dwelling older adults.

METHODS

We randomly assigned participants to OCY or a computer brain game (CBG). After a computer literacy training led by high school students, participants engaged in remotely supervised OCY or CBG in twice-weekly 45-minute sessions for 12 weeks. Outcome data (pain interference, cognitive function, mobility, computer skills) were collected at baseline, post-intervention, and 3-month follow-up.

RESULTS

A total of 32 eligible residents with mean age of 71 years participated in this intervention study. The interventions were feasible (100% recruitment rate, 96.8% retention rate, 100% safety rate). There were significant improvements in pain interference, cognitive function, mobility, and computer skills from baseline to follow-up among participants in both OCY and CBG but no significant differences in outcomes between groups.

CONCLUSIONS

Preliminary results indicated that the CBG was as effective as online OCY in clinical outcomes in these participants. However, this should be confirmed in future studies.

CLINICAL IMPLICATIONS

This telehealth-based intervention is feasible for older adults in rural and digitally underserved communities and could provide a strategy for delivering health-promoting interventions for home-bound older adults at risk for Alzheimer's disease and related dementias (ADRD) and connect caregivers to online resources.

Physical activity interventions in older adults with a cognitive impairment: A critical review of reviews

This critical review explores the review material on physical activity combined with cognitive stimulation interventions in older adults with cognitive impairment and/or dementia. A critical, systematic, review of the review method was used, considering four electronic databases: WEB OF SCIENCE, SCOPUS, MEDLINE, and the COCHRANE ELECTRONIC LIBRARY. The search terms "exercise," "physical activity," "cognitive impairment," "dementia," and "systematic review" were used. All available reviews were marked against predetermined inclusion and exclusion criteria. There were 32 reviews that met the inclusion criteria. A combination of various types of training and aerobic exercises were the most frequently reported interventions; meanwhile, dual task training programs (combining physical exercise with cognitive stimulation), functional training programs along with exercises combination, aerobic exercise as well as strength, stretching, or balance workouts were also reported. The evidence is compelling; exercise can improve physical health by ensuring cognitive, psychological, and behavioral benefits. Overall, exercise can improve the physical and mental health of people living with dementia: there is sufficient evidence to recommend multimodal exercise.

Dietary Patterns and Alzheimer's Disease: An Updated Review Linking Nutrition to Neuroscience

Alzheimer's disease (AD) is a growing concern for the aging population worldwide. With no current cure or reliable treatments available for AD, prevention is an important and growing area of research. A range of lifestyle and dietary patterns have been studied to identify the most effective preventive lifestyle changes against AD and related dementia (ADRD) pathology. Of these, the most studied dietary patterns are the Mediterranean, DASH, MIND, ketogenic, and modified Mediterranean-ketogenic diets. However, there are discrepancies in the reported benefits among studies examining these dietary patterns. We herein compile a narrative/literature review of existing clinical evidence on the association of these patterns with ADRD symptomology and contemplate their preventive/ameliorative effects on ADRD neuropathology in various clinical milieus. By and large, plant-based dietary patterns have been found to be relatively consistently and positively correlated with preventing and reducing the odds of ADRD. These impacts stem not only from the direct impact of specific dietary components within these patterns on the brain but also from indirect effects through decreasing the deleterious effects of ADRD risk factors, such as diabetes, obesity, and cardiovascular diseases. Importantly, other psychosocial factors influence dietary intake, such as the social connection, which may directly influence diet and lifestyle, thereby also impacting ADRD risk. To this end, prospective research on ADRD should include a holistic approach, including psychosocial considerations.

Electrochemical Immunosensors Developed for Amyloid-Beta and Tau Proteins, Leading Biomarkers of Alzheimer's Disease

Alzheimer's disease (AD) is the most common neurological disease and a serious cause of dementia, which constitutes a threat to human health. The clinical evidence has found that extracellular amyloid-beta peptides (Aβ), phosphorylated tau (p-tau), and intracellular tau proteins, which are derived from the amyloid precursor protein (APP), are the leading biomarkers for accurate and early diagnosis of AD due to their central role in disease pathology, their correlation with disease progression, their diagnostic value, and their implications for therapeutic interventions. Their detection and monitoring contribute significantly to understanding AD and advancing clinical care. Available diagnostic techniques, including magnetic resonance imaging (MRI) and positron emission tomography (PET), are mainly used to validate AD diagnosis. However, these methods are expensive, yield results that are difficult to interpret, and have common side effects such as headaches, nausea, and vomiting. Therefore, researchers have focused on developing cost-effective, portable, and point-of-care alternative diagnostic devices to detect specific biomarkers in cerebrospinal fluid (CSF) and other biofluids. In this review, we summarized the recent progress in developing electrochemical immunosensors for detecting AD biomarkers (Aβ and p-tau protein) and their subtypes (AβO, Aβ_(1-40), Aβ_(1-42), t-tau, cleaved-tau (c-tau), p-tau₁₈₁, p-tau₂₃₁, p-tau₃₈₁, and p-tau₄₄₁). We also evaluated the key characteristics and electrochemical performance of developed immunosensing platforms, including signal interfaces, nanomaterials or other signal amplifiers, biofunctionalization methods, and even primary electrochemical sensing performances (i.e., sensitivity, linear detection range, the limit of detection (LOD), and clinical application).

The neurocognitive disorder cohort RIFADE: Aims, methods, first results showing cognitive improvement in a subgroup

BACKGROUND

The NCD cohort study RIFADE (RIsk FActors of DEmentia) investigates the interaction of risk factors and neurocognitive disorders (NCDs) due to Alzheimer's disease (NCD-AD) and NCD of vascular type (NCD-vascular). Retrospective recruitment referred to a period from 2007 to 2018 in a single centre. In addition to the baseline visit, follow-up visits took place at 3, 6, 12 months followed by yearly visits. Visit times varied in part depending on adherence. The study also comprises an EEG bank and a bank with cerebral MRI (c-MRI).

METHODS

Inclusion criteria were broad in order to cover a wide range of patterns of NCD. At baseline, patients underwent a large panel of assessments, e.g. including clinical history, diagnostic evaluation for NCD according to DSM-IV and NINDS AIREN criteria, a cognitive test battery including the DemTect, the clock drawing test and the Instrumental-Activities-of-Daily-Living-scale of Lawton and Brodie, EEG and c-MRI. At each follow-up visit, cognitive tests were repeated, in most cases also EEGs and in some cases c-MRIs. Numerous risk factors (RF) including vascular RF, atrial fibrillation, heart failure, sleep apnoea and lifestyle factors such as sedentary lifestyle, low cognitive style and smoking were evaluated for presence and for correction status at each visit, and modulation of uncorrected RF was initiated.

RESULTS

Overall, 126 subjects with a clinical diagnosis of NCD were included (52% female, mean age 71 ± 10.6 years (range 35e86)), number of follow-up visits per subject 2.9 ± 2.4, observation time per subject 3.4 ± 2.8 years). Of these, 55/28/17% presented with the clinical stages subjective cognitive decline (SCD)/mild cognitive impairment (MCI)/dementia (major NCD). Clinical diagnoses, retrospectively re-evaluated according to DSM-5, were 5/21/68/6% Alzheimer´s disease (NCD-AD)/vascular NCD (NCD-vascular) / mixed NCD (NCD-AD + NCD-vascular)/unspecified NCD. First longitudinal results revealed a mean DemTect score at baseline 12.6 ± 4.2 vs last visit 12.0 ± 4.8 (p = 0.08) and a clock drawing test score at baseline 1.9 ± 1.3 vs last visit 2.3 ± 1.5 (p < 0.0001). Of all subjects with MCI or major NCD (n = 57), 19 improved in the clinical stage from baseline to last visit (33.3%). Sixteen subjects progressed from SCD or MCI (n = 104) to major NCD (15.4%).

CONCLUSION

The German NCD cohort RIFADE comprises patients with all clinical stages of NCD. A considerable subgroup improved in clinical stage. Further analysis is needed to answer the question of whether modulation of multiple risk factors provides a favourable effect on cognitive outcome in NCD.

Network meta-analysis of comparative efficacy of animal-assisted therapy vs. pet-robot therapy in the management of dementia

Objective

This network meta-analysis aimed to compare and rank the efficacy of animal-assisted therapy (AAT) and pet-robotic therapy (PRT) in the management of dementia.

Methods

Relevant studies were identified by searching PubMed, EMBASE, the Cochrane Library, SCOPUS, and Web of Science (WoS) until October 13, 2022. Traditional meta-analysis was first conducted based on the random-effects model, then random network meta-analysis was conducted to determine the relative efficacy and rank probability of AAT and PRT.

Results

Nineteen randomized controlled trials (RCTs) were included in this network meta-analysis. Network meta-analysis revealed that PRT marginally benefited agitation alleviation compared with control (standard mean difference [SMD]: -0.37, 95% confidence interval [95%CI]: -0.72 to -0.01) although both AAT and PRT did not improve cognitive function, reduce depression, and improve Quality of Life (QoL). The SUCRA probabilities indicated that PRT ranked better than AAT in agitation, cognitive function, and QoL, although there were no differences between the two therapies.

Conclusion

The present network meta-analysis reveals that PRT may help alleviate agitated behaviors in people with dementia. However, future studies are warranted to establish evidence of the effectiveness of PRT and further evaluate the differences between different robot types in managing dementia.

Brain function effects of exercise interventions for cognitive decline: a systematic review and meta-analysis

Introduction

Exercise is recognized as a modifiable lifestyle factor that can mitigate cognitive decline and dementia risk. While the benefits of exercise on cognitive aging have been reported on extensively, neuronal effects in adults experiencing cognitive decline have not been systematically synthesized. The aim of this systematic review was to assess the effects of exercise on cognition and brain function in people with cognitive decline associated with dementia risk.

Method

A systematic search was conducted for randomized controlled trials of ≥ 4 weeks exercise (aerobic, resistance, or mind-body) that assessed cognition and brain function using neuroimaging and neurophysiological measures in people with subjective or objective cognitive decline. Study characteristics and brain function effects were narratively synthesized, while domain-specific cognitive performance was subjected to meta-analysis. Study quality was also assessed.

Results

5,204 records were identified and 12 unique trials met the eligibility criteria, representing 646 adults classified with cognitive frailty, mild or vascular cognitive impairment. Most interventions involved 40-minute sessions conducted 3 times/week. Exercise improved global cognition (g = -0.417, 95% CI, -0.694 to -0.140, p = 0.003, I² = 43.56%), executive function (g = -0.391, 95% CI, -0.651 to -0.131, p = 0.003, I² = 13.28%), but not processing speed or general short-term memory (both p >0.05). Across fMRI and ERP studies, significant neuronal adaptations were found with exercise cf. control throughout the brain and were linked with improved global cognition, memory, and executive function. Cerebral blood flow was also found to improve with 24 weeks of exercise, but was not linked with cognitive changes.

Discussion

The cognitive improvements associated with exercise are likely driven by increased metabolic activity, cerebrovascular mechanisms, and neuroplasticity throughout the brain. Our paper shows the promise in, and need for, high-quality trials integrating cognitive and brain function measures to elucidate the functional relationship between exercise and brain health in populations with a high risk of dementia.

Systematic review registration

PROSPERO, identifier: CRD42022291843.

Preventive Strategies for Cognitive Decline and Dementia: Benefits of Aerobic Physical Activity, Especially Open-Skill Exercise

As there is no curative treatment for dementia, including Alzheimer's disease (AD), it is important to establish an optimal nonpharmaceutical preventive intervention. Physical inactivity is a representative modifiable risk factor for dementia, especially for AD in later life (>65 years). As physical activity and exercise are inexpensive and easy to initiate, they may represent an effective nonpharmaceutical intervention for the maintenance of cognitive function. Several studies have reported that physical activity and exercise interventions are effective in preventing cognitive decline and dementia. This review outlines the effects of physical activity and exercise-associated interventions in older adults with and without cognitive impairment and subsequently summarizes their possible mechanisms. Furthermore, this review describes the differences between two types of physical exercise-open-skill exercise (OSE) and closed-skill exercise (CSE)-in terms of their effects on cognitive function. Aerobic physical activity and exercise interventions are particularly useful in preventing cognitive decline and dementia, with OSE exerting a stronger protective effect on cognitive functions than CSE. Therefore, the need to actively promote physical activity and exercise interventions worldwide is emphasized.

Physical activity levels in cognitively normal and cognitively impaired oldest-old and the association with dementia risk factors: a pilot study

BACKGROUND

Research assessing the relationship of physical activity and dementia is usually based on studies with individuals younger than 90 years of age. The primary aim of this study was to determine physical activity levels of cognitively normal and cognitively impaired adults older than 90 years of age (oldest-old). Our secondary aim was to assess if physical activity is associated with risk factors for dementia and brain pathology biomarkers.

METHODS

Physical activity was assessed in cognitively normal (N = 49) and cognitively impaired (N = 12) oldest-old by trunk accelerometry for a 7-day period. We tested physical performance parameters and nutritional status as dementia risk factors, and brain pathology biomarkers. Linear regression models were used to examine the associations, correcting for age, sex and years of education.

RESULTS

Cognitively normal oldest-old were on average active for a total duration of 45 (SD 27) minutes per day, while cognitively impaired oldest-old seemed less physically active with 33 (SD 21) minutes per day with a lower movement intensity. Higher active duration and lower sedentary duration were related to better nutritional status and better physical performance. Higher movement intensities were related to better nutritional status, better physical performance and less white matter hyperintensities. Longer maximum walking bout duration associated with more amyloid binding.

CONCLUSION

We found that cognitively impaired oldest-old are active at a lower movement intensity than cognitively normal oldest-old individuals. In the oldest-old, physical activity is related to physical parameters, nutritional status, and moderately to brain pathology biomarkers.

MidCog study: a prospective, observational cohort study investigating health literacy, self-management skills and cognitive function in middle-aged adults

INTRODUCTION

The lack of definitive means to prevent or treat cognitive impairment or dementia is driving intense efforts to identify causal mechanisms. Recent evidence suggests clinically meaningful declines in cognition might present as early as middle age. Studying cognitive changes in middle adulthood could elucidate modifiable factors affecting later cognitive and health outcomes, yet few cognitive ageing studies include this age group. The purpose of the MidCog study is to begin investigations of less-studied and potentially modifiable midlife determinants of later life cognitive outcomes.

METHODS AND ANALYSIS

MidCog is a prospective cohort study of adults ages 35-64, with two in-person interviews 2.5 years apart. Data will be collected from interviews, electronic health records and pharmacy fill data. Measurements will include health literacy, self-management skills, cognitive function, lifestyle and health behaviours, healthcare use, health status and chronic disease outcomes. Associations of health literacy and self-management skills with health behaviours and cognitive/health outcomes will be examined in a series of regression models, and moderating effects of modifiable psychosocial factors.Finally, MidCog data will be linked to an ongoing, parallel cohort study of older adults recruited at ages 55-74 in 2008 ('LitCog'; ages 70-90 in 2023), to explore associations between age, health literacy, self-management skills, chronic diseases, health status and cognitive function among adults ages 35-90.

ETHICS AND DISSEMINATION

The Institutional Review Board at Northwestern University has approved the MidCog study protocol (STU00214736). Results will be published in peer-reviewed journals and summaries will be provided to the funders of the study as well as patients.

Simulating the multicausality of Alzheimer's disease with system dynamics

INTRODUCTION

In Alzheimer's disease (AD), cognitive decline is driven by various interlinking causal factors. Systems thinking could help elucidate this multicausality and identify opportune intervention targets.

METHODS

We developed a system dynamics model (SDM) of sporadic AD with 33 factors and 148 causal links calibrated with empirical data from two studies. We tested the SDM's validity by ranking intervention outcomes on 15 modifiable risk factors to two sets of 44 and 9 validation statements based on meta-analyses of observational data and randomized controlled trials, respectively.

RESULTS

The SDM answered 77% and 78% of the validation statements correctly. Sleep quality and depressive symptoms yielded the largest effects on cognitive decline with which they were connected through strong reinforcing feedback loops, including via phosphorylated tau burden.

DISCUSSION

SDMs can be constructed and validated to simulate interventions and gain insight into the relative contribution of mechanistic pathways.

Evaluation of Cognitive and Physical Function Among Older Adults by Their Physical Activity: A Cross-Sectional Kasama Study, Japan

BACKGROUND

The amyloid-β1-42 (Aβ42) level is a biomarker that is widely used to evaluate individual cognitive dysfunction early in neurodegenerative diseases, as well as differentiate between normal cognitive function, mild cognitive impairment, Alzheimer's disease, and vascular cognitive impairment.

OBJECTIVE

Our cross-sectional study evaluated the association between daily exercise and physical and cognitive function and Aβ42 levels among a subsample of 325 older adults from the Kasama Study.

METHODS

Participants (age: 74.5 [range 65-90] years) were classified into three exercise groups: the dual-task (DEG, n = 128), single-task (SEG, n = 122), and non-exercise (NEG, n = 75) groups. The main outcomes were the plasma Aβ42 levels and the scores of the five cognitive (5-COG) tests and five cognition-related physical function (5-PHYS) tests.

RESULTS

The Aβ42 levels and 5-COG and 5-PHYS scores were higher in the SEG and DEG than in the NEG. The Aβ42 levels were higher in the DEG than in the NEG (p = 0.008).

CONCLUSIONS

Physical activities such as regular exercise may benefit older adults, improving their cognitive and physical function.

Epidemiological Characteristics and Factors Associated with Alzheimer's Disease and Mild Cognitive Impairment among the Elderly in Urban and Rural Areas of Hubei Province

Utilize the prevalence, associated factors and population distribution of AD and MCI among residents of the Hubei province aged 60 years or over to prove that elderly people who study and communicate with others, take part in regular physical exercise and choose a healthy lifestyle, will prevent or slow the decline in cognitive ability. If elderly people study and communicate with others, take part in regular physical exercise and choose a healthy lifestyle, can prevent or slow the decline in cognitive ability. A cross-sectional study was used for the recruitment of subjects. The screened patients with AD and MCI were then selected as patients in a case−control study. A total of 4314 subjects were recruited into the study. The prevalence of AD and MCI was 1.44% and 10.04%, respectively. The prevalence of AD and MCI differed significantly as a function of age and gender (p < 0.05). The preventative factors for AD and MCI, separately, included a happy marriage (OR = 0.69, 95%CI: 0.36−1.35) and higher education (OR = 0.65, 95%CI: 0.55−0.78). The risk factors for AD and MCI, separately, included infrequent participation in social activities (OR = 1.00, 95%CI: 0.60−1.66) and infrequent communication with children (OR = 1.35, 95%CI: 1.09−1.69). The prevalence of AD for people aged 60 or over in the Hubei province was lower than the national average of 3.06%. The prevalence of MCI was within the national range (5.2−23.4%). The influencing factors of AD and MCI were associated with the participants’ social connections, lifestyle behaviors, somatic diseases and so on. The elderly people who study and communicate with others, take part in regular physical exercise and choose a healthy lifestyle will prevent or slow the decline in cognitive ability. The conclusion section has been replaced.

Effect of physical activity on the risk of frailty: A systematic review and meta-analysis

OBJECTIVE

The relationship between physical activity (PA) and the risk of frailty has not reached a conclusive result. This systematic review with meta-analysis aimed to evaluate the effect of PA on the onset of frailty in the community-dwelling middle and older age adults by pooling data from cohort studies.

METHODS

A systematic literature search was performed via PubMed, Embase, and Web of Science up to June 01, 2021. Pooled adjusted effect estimates (ES) with 95% confidence interval (CI) were calculated by using the random-effect model and by comparing the highest with lowest levels of PA. Heterogeneity was tested using the I2 statistic and Q-test. The quality of evidence was evaluated by using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

RESULTS

A total of ten cohort studies with 14 records were selected, and the GRADE approach classified the quality of evidence as low. In comparison with the lowest level of PA, the highest level of PA was associated with 41% decreased odds of frailty (ES: 0.59, 95% CI: 0.51-0.67; I2 = 70.0%, P-heterogeneity < 0.001) after pooling results from included studies. In stratified analysis by frailty assessment approach, the highest level of PA was significantly associated with 37% (ES 0.63, 95% CI: 0.52-0.77, 49% (ES: 0.51, 95% CI: 0.41-0.63), and 30% (ES: 0.70, 95% CI: 0.65-0.75) reduced odds of frailty when pooling studies using criteria of physical frailty, multidimensional model, and accumulation of disability, respectively. Stratified analyses further by PA indicators and PA assessment tools yielded similar protective effects in any subgroups.

CONCLUSIONS

This study with moderate-certainty evidence shows that a higher level of PA was associated with lower odds of frailty, and the benefits of PA for frailty prevention were independent of frailty assessment tools, PA indicators, and PA assessment methods. Findings from this study may help implement active exercise strategies to prevent frailty.

Understanding the Intricate Role of Exosomes in Pathogenesis of Alzheimer's Disease

Alzheimer's disease causes loss of memory and deterioration of mental abilities is utmost predominant neurodegenerative disease accounting 70-80% cases of dementia. The appearance of plaques of amyloid-β and neurofibrillary tangles in the brain post-mortems of Alzheimer's patients established them as key participants in the etiology of Alzheimer's disease. Exosomes exist as extracellular vesicles of nano-size which are present throughout the body. Exosomes are known to spread toxic hyperphosphorylated tau and amyloid-β between the cells and are linked to the loss of neurons by inducing apoptosis. Exosomes have progressed from cell trashcans to multifunctional organelles which are involved in various functions like internalisation and transmission of macromolecules such as lipids, proteins, and nucleic acids. This review covers current findings on relationship of exosomes in biogenesis and angiogenesis of Alzheimer's disease and functions of exosomes in the etiology of AD. Furthermore, the roles of exosomes in development, diagnosis, treatment, and its importance as therapeutic targets and biomarkers for Alzheimer's disease have also been highlighted.

Altered glucose metabolism in Alzheimer's disease: Role of mitochondrial dysfunction and oxidative stress

Increasing evidence suggests that abnormal cerebral glucose metabolism is largely present in Alzheimer's disease (AD). The brain utilizes glucose as its main energy source and a decline in its metabolism directly reflects on brain function. Weighing on recent evidence, here we systematically assessed the aberrant glucose metabolism associated with amyloid beta and phosphorylated tau accumulation in AD brain. Interlink between insulin signaling and AD highlighted the involvement of the IRS/PI3K/Akt/AMPK signaling, and GLUTs in the disease progression. While shedding light on the mitochondrial dysfunction in the defective glucose metabolism, we further assessed functional consequences of AGEs (advanced glycation end products) accumulation, polyol activation, and other contributing factors including terminal respiration, ROS (reactive oxygen species), mitochondrial permeability, PINK1/parkin defects, lysosome-mitochondrial crosstalk, and autophagy/mitophagy. Combined with the classic plaque and tangle pathologies, glucose hypometabolism with acquired insulin resistance and mitochondrial dysfunction potentiate these factors to exacerbate AD pathology. To this end, we further reviewed AD and DM (diabetes mellitus) crosstalk in disease progression. Taken together, the present work discusses the emerging role of altered glucose metabolism, contributing impact of insulin signaling, and mitochondrial dysfunction in the defective cerebral glucose utilization in AD.

Social participation and mild cognitive impairment in low- and middle-income countries

Social participation may theoretically decrease risk for mild cognitive impairment (MCI). However, to date, no study has specifically investigated the association between social participation and MCI in LMICs, while the mediating role of loneliness is unknown. Thus, we investigated this association in a sample of adults aged ≥50 years from six low- and middle-income countries (LMICs; China, Ghana, India, Mexico, Russia, South Africa) using nationally representative datasets. We analyzed cross-sectional, community-based data from the Study on Global Ageing and Adult Health. A social participation score (range 0-10 with higher scores corresponding to greater levels of social participation) was created based on nine questions about involvement in community activities in the last 12 months. The National Institute on Ageing-Alzheimer's Association criteria were used to define MCI. Multivariable logistic regression and mediation analysis was performed. The analytical sample consisted of 32,715 individuals aged ≥50 years with preserved functional abilities [mean (SD) age 62.1 (15.6) years; 51.7% females]. In the overall sample, after adjustment for potential confounders, a one-unit increase in the social participation score was associated with a 13% decrease in odds for MCI (OR = 0.87; 95%CI = 0.82-0.93). Loneliness only explained 3.0% of the association. Greater levels of social participation were associated with a reduced odds for MCI, and this was not largely explained by loneliness. It may be prudent to implement interventions in LMICs to increase levels of social participation to aid in the prevention of MCI and ultimately dementia.

Correlates of cognitive impairment in the elderly in China: A cross-sectional study

Background

To identify correlates of the incidence of cognitive impairment among older Chinese populations through the use of logistic regression analysis-based decision tree approaches.

Methods

Correlates of cognitive impairment among older Chinese adults were identified through logistic regression analyses, with significant variables subsequently being incorporated into a decision tree analysis, with the CHAID method being employed for pre-pruning.

Results

The risk score derived from the combination of logistic regression and decision tree analyses (0.237) was lower than that derived from a decision tree analysis alone (0.389). The primary factors related cognitive impairment in this patient population included age, gender, residence status, physical health status, and caring for grandchildren.

Conclusion

A combination of logistic regression and decision tree analyses can lower predicted risk scores, enabling the subdivision of populations with different characteristics and providing intuitive and specific insight regarding the effects of individual variables on predictive analyses. Overall, these results suggest that older adults in rural areas of China should be the focus of further cognitive impairment screening and interventions, particularly for older women.

A Bibliometric and Visual Analysis of Exercise Intervention Publications for Alzheimer’s Disease (1998–2021)

Alzheimer’s disease (AD) is the most common cause of dementia worldwide, posing a considerable economic burden to patients and society as a whole. Exercise has been confirmed as a non-drug intervention method in the related literature on AD. However, at present, there are still few bibliometric studies on AD exercise research. In order to fill the gap, this paper aims to intuitively analyze the growth in AD exercise literature published from 1998 to 2021 using bibliometrics, providing historical insights for scientific research circles. The main source of literature retrieval is the Web of Science database. Using the Boolean operator tools “OR” and “AND” combined with keywords related to “exercise” and “Alzheimer’s disease”, we conducted a title search and obtained 247 documents. Using Microsoft Excel, Datawrapper, and Biblioshiny, this study carried out a bibliometric analysis of countries, institutions, categories, journals, documents, authors, and keyword plus terms. The study found that the number of papers published from 2016 to 2021 had the greatest increase, which may have been influenced by the Global Dementia Report 2015 and COVID-19. Interdisciplinary cooperation and the research results published in high-scoring journals actively promoted research and development in the AD exercise field. The United States and the University of Minnesota system play a central role in this field. In future, it will be necessary to explore the effectiveness and feasibility of multi-mode interventions on an active lifestyle, including exercise, in different groups and environments worldwide. This study may provide a direction and path for future research by showing the global overview, theme evolution, and future trends of research results in the AD exercise field.

Capturing Cognitive Aging in Vivo: Application of a Neuropsychological Framework for Emerging Digital Tools

As the global burden of dementia continues to plague our healthcare systems, efficient, objective, and sensitive tools to detect neurodegenerative disease and capture meaningful changes in everyday cognition are increasingly needed. Emerging digital tools present a promising option to address many drawbacks of current approaches, with contexts of use that include early detection, risk stratification, prognosis, and outcome measurement. However, conceptual models to guide hypotheses and interpretation of results from digital tools are lacking and are needed to sort and organize the large amount of continuous data from a variety of sensors. In this viewpoint, we propose a neuropsychological framework for use alongside a key emerging approach—digital phenotyping. The Variability in Everyday Behavior (VIBE) model is rooted in established trends from the neuropsychology, neurology, rehabilitation psychology, cognitive neuroscience, and computer science literature and links patterns of intraindividual variability, cognitive abilities, and everyday functioning across clinical stages from healthy to dementia. Based on the VIBE model, we present testable hypotheses to guide the design and interpretation of digital phenotyping studies that capture everyday cognition in vivo. We conclude with methodological considerations and future directions regarding the application of the digital phenotyping approach to improve the efficiency, accessibility, accuracy, and ecological validity of cognitive assessment in older adults.

Cognitive Function Is Associated With Multiple Indices of Adiposity in the Canadian Longitudinal Study on Aging: A Cross-Sectional Analysis

OBJECTIVE

Prior studies have suggested reciprocal relationships between cognitive function and adiposity, but this has not been investigated with population representative data sets. The purpose of this study was to examine the association between cognitive function and adiposity in a large population-based sample of middle-aged and older adults. It was hypothesized that better scores on tests of cognitive function would be associated with lower adiposity, and this association would be primarily mediated through life-style behavior and physical health status.

METHODS

Using baseline data from the Canadian Longitudinal Study on Aging ( N = 30,097), we tested our hypotheses using three indicators of cognitive function (animal fluency, Stroop interference, and reaction time) and four indicators of adiposity (body mass index, total fat mass, waist circumference, and waist-hip ratio). Hierarchical multivariable linear regression modeling was conducted followed by tests for moderation by socioeconomic status and mediation through diet, physical activity, hypertension, and diabetes status.

RESULTS

All measures of cognitive indicators were significantly associated with adiposity after adjusting for confounders. In general, superior performance on animal fluency, Stroop, and reaction time tasks were associated with lower adiposity by most metrics. Stroop interference was associated with lower adiposity across all metrics, including body mass index ( b = - 0.04, 95 % confidence interval [CI] = - 0.06  to - 0.01), total fat mass ( b = 19.35, 95 % CI = 8.57  to 30.12), waist circumference ( b = 33.83, 95 % CI = 10.08  to 57.58), and waist-hip ratio ( b = 0.13, 95 % CI = 0.01  to 0.24). These associations were more substantial for moderate- and high-income subpopulations. Mediation analyses suggested that the aforementioned effects were mediated through life-style behavior (e.g., diet and physical activity) and physical health conditions (e.g., diabetes and hypertension).

CONCLUSIONS

Reliable associations exist between cognitive function and adiposity in middle-aged and older adults. The associations seem to be mediated through life-style behavior and physical health conditions.

Diet quality interventions to prevent neurocognitive decline: a systematic review and meta-analysis

OBJECTIVE

To determine the impact of diet quality interventions on neurocognitive decline in older adults.

DESIGN

Four databases were searched (Medline, EMBASE, CENTRAL and PsycINFO) for randomised controlled trials involving diet quality interventions and cognitive outcomes in older adults. Study quality was assessed using the Cochrane Risk of Bias tool. Outcomes selected for meta-analysis were memory and executive function, for which standardised mean differences (SMD) were calculated. Subgroup and sensitivity analyses were undertaken to explore causes of heterogeneity. Additional outcomes of global cognitive function, incident dementia, attention, language/verbal fluency, and processing speed were narratively synthesised.

RESULTS

Twelve studies were included, investigating the Mediterranean, Dietary Approaches to Stop Hypertension and Nordic diets. Risk of bias varied across studies. Dietary intervention had a significant effect on memory (SMD: 0.98; 95% CI: 0.39, 1.57; p = 0.001) and executive function (SMD: 2.02; 95% CI: 1.04, 3.01; p < 0.00001), although neither outcome was significant in sensitivity analyses. Heterogeneity was high (I² = 99%) prior to sensitivity analyses and low (I² = 0%) after. Results for narratively synthesised cognitive measures were inconsistent with no clear direction of effect.

CONCLUSION

The current body of evidence would suggest the effect of dietary intervention on neurocognitive decline in older adults is unclear given the considerable heterogeneity and bias present across studies. These findings should be interpreted with consideration to the limited number of studies that could be included and the large variation in study designs. Further randomised controlled trials with harmonised cognitive outcomes and assessments are needed to clarify direction of effect.

Exploring the Associations between Functional Capacity, Cognitive Function and Well-Being in Older Adults

Background: The present study aimed to explore the associations between functional capacity and global cognition, executive function and well-being in older adults. Methods: Ninety-seven older adults (age 80.6 ± 8.2 years) were examined for global cognitive function (Mini-Mental State Examination), executive function (symbol cancellation test), functional capacity (sit-to-stand tests, 6 min walk test, timed up-and-go test and handgrip strength test) and well-being (quality of life, fatigue levels, sleep quality and daily sleepiness). Adjusted partial correlations were computed to examine the associations between variables. Mediation analyses were conducted to evaluate whether functional capacity would mediate the relationships between age and cognitive or executive function. Results: Greater levels of functional capacity were associated with better performance in cognitive and executive function tests (p < 0.05). Mediation analyses revealed that functional capacity partially mediated the effects of age on global cognition and executive function (indirect effect: β = −0.11, 95% CI = −0.20 to −0.03; β = 0.34, 95% CI = 0.13 to 0.57, respectively). Increased levels of functional capacity were also associated with higher quality of life (p < 0.05, r = 0.32 to 0.41), lower fatigue levels (p < 0.05, r = 0.23 to 0.37), and better sleep quality (p < 0.05, r = 0.23 to 0.24). Conclusions: Functional capacity can mediate the effects of age on global cognition and executive function in older adults and greater levels of functional capacity are associated with improved quality of life, better sleep quality, and lower fatigue levels.

Neurovascular Dysfunction in Diverse Communities With Health Disparities-Contributions to Dementia and Alzheimer's Disease

Alzheimer's disease and related dementias (ADRD) are an expanding worldwide crisis. In the absence of scientific breakthroughs, the global prevalence of ADRD will continue to increase as more people are living longer. Racial or ethnic minority groups have an increased risk and incidence of ADRD and have often been neglected by the scientific research community. There is mounting evidence that vascular insults in the brain can initiate a series of biological events leading to neurodegeneration, cognitive impairment, and ADRD. We are a group of researchers interested in developing and expanding ADRD research, with an emphasis on vascular contributions to dementia, to serve our local diverse community. Toward this goal, the primary objective of this review was to investigate and better understand health disparities in Alabama and the contributions of the social determinants of health to those disparities, particularly in the context of vascular dysfunction in ADRD. Here, we explain the neurovascular dysfunction associated with Alzheimer's disease (AD) as well as the intrinsic and extrinsic risk factors contributing to dysfunction of the neurovascular unit (NVU). Next, we ascertain ethnoregional health disparities of individuals living in Alabama, as well as relevant vascular risk factors linked to AD. We also discuss current pharmaceutical and non-pharmaceutical treatment options for neurovascular dysfunction, mild cognitive impairment (MCI) and AD, including relevant studies and ongoing clinical trials. Overall, individuals in Alabama are adversely affected by social and structural determinants of health leading to health disparities, driven by rurality, ethnic minority status, and lower socioeconomic status (SES). In general, these communities have limited access to healthcare and healthy food and other amenities resulting in decreased opportunities for early diagnosis of and pharmaceutical treatments for ADRD. Although this review is focused on the current state of health disparities of ADRD patients in Alabama, future studies must include diversity of race, ethnicity, and region to best be able to treat all individuals affected by ADRD.

Associations of Short-Term Exposure to Fine Particulate Matter with Neural Damage Biomarkers: A Panel Study of Healthy Retired Adults

Exposure to fine particulate matter (PM_2.5) is associated with various adverse health effects, such as respiratory and cardiovascular diseases. This study aimed to evaluate the association of PM_2.5 with neural damage biomarkers. A total of 34 healthy retirees were recruited from Xinxiang Medical University from December 2018 to April 2019. Concentrations of PM_2.5 constituents including 24 metals and nonmetallic elements and 6 ions, and 5 biomarkers of neural damage including brain-derived neurotrophic factor (BDNF), neurofilament light chain (NfL), neuron-specific enolase (NSE), protein gene product 9.5 (PGP9.5), and S100 calcium-binding protein B (S100B) in serum were measured. A linear mixed-effect model was employed to estimate the association of PM_2.5 and its constituents with neural damage biomarkers. Modification effects of glutathione S-transferase theta 1 gene (GSTT1) polymorphism, sex, education, and physical activity on PM_2.5 exposure with neural damage were explored. PM_2.5 and its key constituents were significantly associated with neural damage biomarkers. A 10 μg/m³ increase in PM_2.5 concentration was associated with 2.09% (95% CI, 39.3-76.5%), 100% (95% CI, 1.73-198%), and 122% (95% CI, 20.7-222%) increments in BDNF, NfL, and PGP9.5, respectively. Several constituents such as Cu, Zn, Ni, Mn, Sn, V, Rb, Pb, Al, Be, Cs, Co, Th, U, Cl^-, and F^- were significantly associated with NfL. The estimated association of PM_2.5 with NSE in GSTT1-sufficient volunteers was significantly higher than that in GSTT1-null volunteers. Therefore, short-term PM_2.5 exposure was associated with neural damage, and GSTT1 expression levels modified the PM_2.5-induced adverse neural effects.

Development of a multi-component intervention to promote sleep in older persons with dementia transitioning from hospital to home

BACKGROUND

Hospitalised older persons with dementia are commonly discharged with intensified sleep disturbances. These disturbances can impede the recovery process. Nurses are well-positioned to assist persons with dementia and their family caregivers in managing sleep disturbances during the transition from hospital to home.

OBJECTIVES

To describe the development of a multi-component intervention to promote sleep.

METHODS

We applied three stages of the intervention mapping method to develop a non-pharmacological, multi-component sleep intervention. The first stage involved a review of the literature to generate an understanding of the determinants of sleep disturbances experienced by persons with dementia in hospital and home settings. The second stage consisted of a literature review to identify therapies for managing commonly reported determinants of sleep disturbances. The third stage entailed delineation of the intervention components.

RESULTS

The most common determinants of sleep disturbances experienced by persons with dementia in hospital and home settings were: physiological changes associated with ageing, sleep environments non-conducive to sleep, limited exposure to light and engagement in physical activity, stress and sleep-related beliefs and behaviours. Therapies found effective included: light therapy, physical activity therapy, sleep hygiene, and stimulus control therapy. These therapies were integrated into a multi-component sleep intervention to be provided using the teach-back technique, during and following hospitalisation.

DISCUSSION

Consistent with the principles of patient engagement, the multi-component sleep intervention will be evaluated for its acceptability and feasibility.

IMPLICATIONS FOR PRACTICE

The intervention has potentials to improve sleep during the transition from hospital to home.

Covariance and Correlation Analysis of Resting State Functional Magnetic Resonance Imaging Data Acquired in a Clinical Trial of Mindfulness-Based Stress Reduction and Exercise in Older Individuals

We describe and apply novel methodology for whole-brain analysis of resting state fMRI functional connectivity data, combining conventional multi-channel Pearson correlation with covariance analysis. Unlike correlation, covariance analysis preserves signal amplitude information, which feature of fMRI time series may carry physiological significance. Additionally, we demonstrate that dimensionality reduction of the fMRI data offers several computational advantages including projection onto a space of manageable dimension, enabling linear operations on functional connectivity measures and exclusion of variance unrelated to resting state network structure. We show that group-averaged, dimensionality reduced, covariance and correlation matrices are related, to reasonable approximation, by a single scalar factor. We apply this methodology to the analysis of a large, resting state fMRI data set acquired in a prospective, controlled study of mindfulness training and exercise in older, sedentary participants at risk for developing cognitive decline. Results show marginally significant effects of both mindfulness training and exercise in both covariance and correlation measures of functional connectivity.

Relationship between physical activity and cognitive functioning among older Indian adults

In a culturally different and low-resource setting, where lifestyle habits, including dietary pattern and physical activities differ from those in high-income countries, the association between physical activity and cognition is expected to differ. We aimed to investigate the association between physical activity and cognitive functioning after controlling for potential confounders among older adults in India. Furthermore, gender differences in this relationship were analyzed. Using a national-level data from the Longitudinal Ageing Study in India (2017-2018), this paper employed propensity score matching (PSM) approach to examine the association between physical activities and cognitive functioning among Indian older adults. Cognitive impairment was measured through five broad domains (memory, orientation, arithmetic function, executive function, and object naming). We limit our sample to older adults aged 60 + years, and our final dataset contains 31,464 participants (men = 16,366, and women = 15,098). The results indicated that older adults who engaged in frequent physical activity have greater cognitive functioning than older adults without physical activity after adjusting for various individual, health, lifestyle, and household factors. This association holds true for both older men and older women. The results from the PSM revealed that the cognitive function score was increased by 0.98 and 1.32 points for the frequently physically active older men and women population, respectively. The results demonstrate the possible beneficial effects of frequent physical activity on cognitive functioning among older adults. Thus, regular physical activity can be considered as an effective lifestyle factor to promote healthy cognitive aging.

Can dietary patterns prevent cognitive impairment and reduce Alzheimer's disease risk: exploring the underlying mechanisms of effects

Alzheimer's disease (AD) is one of the fastest growing cognitive decline-related neurological diseases. To date, effective curative strategies have remained elusive. A growing body of evidence indicates that dietary patterns have significant effects on cognitive function and the risk of developing AD. Previous studies on the association between diet and AD risk have mainly focused on individual food components and specific nutrients, and the mechanisms responsible for the beneficial effects of dietary patterns on AD are not well understood. This article provides a comprehensive overview of the effects of dietary patterns, including the Mediterranean diet (MedDiet), dietary approaches to stop hypertension (DASH) diet, Mediterranean-DASH diet intervention for neurological delay (MIND), ketogenic diet, caloric restriction, intermittent fasting, methionine restriction, and low-protein and high-carbohydrate diet, on cognitive impairment and summarizes the underlying mechanisms by which dietary patterns attenuate cognitive impairment, especially highlighting the modulation of dietary patterns on cognitive impairment through gut microbiota. Furthermore, considering the variability in individual metabolic responses to dietary intake, we put forward a framework to develop personalized dietary patterns for people with cognitive disorders or AD based on individual gut microbiome compositions.

A personalized mobile app for physical activity: An experimental mixed-methods study

Objectives

To investigate the feasibility of the be.well app and its personalization approach which regularly considers users’ preferences, amongst university students.

Methods

We conducted a mixed-methods, pre-post experiment, where participants used the app for 2 months. Eligibility criteria included: age 18–34 years; owning an iPhone with Internet access; and fluency in English. Usability was assessed by a validated questionnaire; engagement metrics were reported. Changes in physical activity were assessed by comparing the difference in daily step count between baseline and 2 months. Interviews were conducted to assess acceptability; thematic analysis was conducted.

Results

Twenty-three participants were enrolled in the study (mean age = 21.9 years, 71.4% women). The mean usability score was 5.6 ± 0.8 out of 7. The median daily engagement time was 2 minutes. Eighteen out of 23 participants used the app in the last month of the study. Qualitative data revealed that people liked the personalized activity suggestion feature as it was actionable and promoted user autonomy. Some users also expressed privacy concerns if they had to provide a lot of personal data to receive highly personalized features. Daily step count increased after 2 months of the intervention (median difference = 1953 steps/day, p-value <.001, 95% CI 782 to 3112).

Conclusions

Incorporating users’ preferences in personalized advice provided by a physical activity app was considered feasible and acceptable, with preliminary support for its positive effects on daily step count. Future randomized studies with longer follow up are warranted to determine the effectiveness of personalized mobile apps in promoting physical activity.

Different Exercise Time on 5-HT and Anxiety-like Behavior in the Rat With Vascular Dementia

BACKGROUND

Previous studies have demonstrated that pre-exercise suppresses anxiety-like behavior, but the effects of different exercise times on vascular dementia induced anxiety-like behavior have not been well investigated.

OBJECTIVE

The present study aims to investigate the underlying neurochemical mechanism of different pre-vascular-dementia exercise times on 5-HT and anxiety-like behavior in rats with vascular dementia.

METHODS

32 Sprague-Dawley (SD) rats were randomly divided into 4 groups: sham group (S group, n = 8), vascular dementia group (VD group, n = 8), 1-week physical exercise and vascular dementia group (1WVD group, n = 8), and 4 weeks physical exercise and vascular dementia group (4WVD group, n = 8). 1 week and 4 weeks of voluntary wheel running were used as pre-exercise training. The vascular dementia model was established by bilateral common carotid arteries occlusion (BCCAo) for 1 week. But bilateral common carotid arteries were not ligated in the sham group. The level of hippocampal 5-HT was detected with in vivo microdialysis coupled with high-performance liquid chromatography (MD-HPLC). Elevated plus maze (EPM), open field (OF), and light/dark box test were used to test anxiety-like behavior.

RESULTS

Compared with the C group, the hippocampal 5-HT was significantly decreased in the VD group after 1 week of ligated operation. The hippocampal 5-HT levels in 1WVD and 4WVD groups were substantially higher than the level in the VD group. The hippocampal 5-HT level has no significant difference among C, 1WVD, and 4WVD. Behavioral data suggested that the rats in the VD group developed obvious anxiety-like behavior after 1 week of ligation surgery. Still, the rats in 1WVD and 4WVD groups did not show significant anxiety-like behavior.

CONCLUSION

Both 1 week and 4 weeks of voluntary running wheel exercise can inhibit the anxiety-like behavior in rats with vascular dementia by upregulating 5-HT levels in the hippocampus in the VD model.

Physical Exercise Exerts Neuroprotective Effect on Memory Impairment by Mitigate the Decline of Striatum Catecholamine and Spine Density in a Vascular Dementia Rat Model

OBJECTIVE

The present study aims to investigate the underlying neurochemical mechanism of physical exercise on striatum synapsis and memory function in vascular dementia model.

METHODS

32 Sprague-Dawley (SD) rats were randomly divided into 4 groups: control group (C group, n = 6), vascular dementia group (Vascular dementia group, n = 7), physical exercise and vascular dementia group (Exe-VD group, n = 6), physical exercise and black group (Exe group, n = 6). 4 weeks of voluntary wheel running were used as pre-exercise training. Vascular dementia model was established by bilateral common carotid arteries occlusion (BCCAo) for 1 week. Passive avoidance test (PAT) were used to test memory function. The level of striatum catecholamine in the microdialysate were detected by enzyme linked immunosorbent assy (ELISA). Golgi staining was used to analyze striatum neuronal spine density.

RESULTS

Behavioral data indicated that 4 weeks of physical exercise ameliorated memory impairment in vascular dementia model. Striatum catecholamine level significantly decreased in VD group when compared with C group (P < .001). But this phenomenon can be rescue by physical exercise (P < .001). In addition, compared with C group, neuronal spine density significantly decreased in VD group (P < .01), but 4 weeks of physical exercise can rescue this phenomenon (P < .05).

CONCLUSION

4 weeks of physical exercise improves memory function by mitigate the decline of striatum catecholamine and spine density in VD model.

Changes in Physical and Cognitive Function Predict Sedentary Behavior in Older Adults With Mild Cognitive Impairment

The current longitudinal study examined the influence of cognitive and lower extremity function on sedentary behavior continuously over 6 months in community-dwelling older adults with mild cognitive impairment (MCI). Multilevel models examined Montreal Cognitive Assessment (MoCA) change scores and the Short Physical Performance Battery (SPPB) on percent time in sedentary behavior among 17 older adults with MCI (50 to 74 observations for analysis). Sedentary behavior was measured daily and averaged monthly using wrist-worn actigraphy. Each 1-unit decrease in MoCA score was associated with an increase of 2 percentage points in sedentary behavior (p ≤ 0.01). In addition, each 1-unit decrease in chair stand score (lower extremity strength) was associated with an increase of 5 percentage points in sedentary behavior (p ≤ 0.01). Older adults experiencing cognitive decline and concurrent changes in lower extremity strength had the sharpest increase in sedentary behavior. Findings suggest lower body strengthening interventions may reduce sedentary behavior time and subsequently preserve physical functioning in this vulnerable population. [Research in Gerontological Nursing, 14(6), 285-291.].

Current physiotherapy practice on delivering treatments for older people with dementia in Indonesia: A cross-sectional study

OBJECTIVES

The aims of the study were to i) explore the current practice, roles, and perceptions of physiotherapists who treat older people with and without dementia in Indonesia, ii) identify the characteristics of physiotherapists associated with treating older people and older people with dementia, and iii) identify the level of knowledge and attitudes about dementia among physiotherapists treating people with dementia in Indonesia.

METHODS

This was a cross-sectional study in which registered physiotherapists in Indonesia were surveyed online using Qualtrics. Descriptive statistics, linear regression and univariate logistic regression were used in this study. Multiple logistic regression was conducted to identify the characteristics of physiotherapists associated with treating older people and/or people with dementia. The Dementia Knowledge Assessment Scale (DKAS) was used to assess level of knowledge and attitudes about dementia. Qualitative data from the survey were analyzed using thematic content analysis.

RESULTS

The online survey was sent to 6327 physiotherapists who met the inclusion criteria and 1061 (16.8%) returned the survey. Eight hundred and eighty-four (83.3%) respondents worked with older patients, and 632 (59.6%) worked with people with dementia. The multiple regression analysis showed that physiotherapists who have been practicing for longer (years) (OR: 1.0, 95%CI: 1.0-1.1, p ≤ 0.001) and were working in a geriatrics area (OR: 3.0, 95%CI: 1.4-6.5, p = 0.005) were more likely to treat older people with dementia. The DKAS mean score (SD) was 32.1 (±5.1)/50 indicating some limitations in dementia knowledge by respondents, and 62% of physiotherapists reported low levels of confidence in treating older people with dementia.

CONCLUSIONS

The relatively low dementia knowledge, and generally low confidence in treating people with dementia among Indonesian physiotherapists were important findings in this study. This study highlights opportunities for improvement in physiotherapist's knowledge and skills in this emerging area of practice in Indonesia.

Differences in Subjective Memory Impairment, Depressive Symptoms, Sleep, and Physical Activity in African American and Asian American Elderly

Background: Subjective memory impairment (SMI) is associated with negative health outcomes including mild cognitive impairment and Alzheimer's disease. However, ethnic differences in SMI and disparities in risk factors associated with SMI among minority populations are understudied. The study examined the ethnic differences in SMI, whether SMI was associated with depressive symptoms, sleep, and physical activity (PA), and whether the associations vary across racial/ethnic groups. Methods: Participants included 243 African and Asian Americans (including Chinese, Vietnamese, and Korean Americans) aged 50 or older. Demographic information, SMI, depressive symptoms, daily sleeping hours, and PA levels were assessed. Results: Vietnamese Americans reported the highest SMI score. Depressive symptoms, sleeping hours, and PA levels were significantly associated with SMI. Depressive symptoms were the only significant factor across all ethnic groups. Significant interaction effects were found between ethnicity and health behaviors in predicting SMI. In particular, Vietnamese American participants with greater depressive symptoms and physical inactivity were significantly more likely to experience SMI compared to other ethnic groups Conclusions: Our findings demonstrate ethnic differences in SMI and its association with depressive symptoms, sleep, and PA, which highlight the importance of considering the unique cultural and historical backgrounds across different racial/ethnic groups when examining cognitive functioning in elderly.

Effects of Aerobic Dance on Cognition in Older Adults with Mild Cognitive Impairment: A Systematic Review and Meta-Analysis

BACKGROUND

Regular aerobic exercises could improve global cognition in older adults with mild cognitive impairment (MCI), such as aerobic dance a type of commonly practiced aerobic exercises. However, its effects remain debatable in improving the cognitive function in patients with MCI.

OBJECTIVE

The aim of this systematic review and meta-analysis is to evaluate the effects of aerobic dance on cognitive function among older adults with MCI.

METHODS

We searched articles in the MEDLINE, PubMed, Embase, and The Cochrane Library databases from inception to 28 February 2019, with the following criteria: 1) randomized controlled trials; 2) older adults with MCI; 3) aerobic dance intervention.

RESULTS

Five studies of 842 participants were identified. This meta-analysis showed that aerobic dance can significantly improve global cognition (Mini-Mental State Examination: MD = 1.43; 95% CI:[0.59, 2.27]; p = 0.0009; Alzheimer's Disease Assessment Scale-Cognitive Subscale: MD=-2.30; 95% CI:[-3.60, -1.00]; p = 0.0005), and delayed recall ability (SMD = 0.46;95% CI: [0.30, 0.62]; p < 0.00001) in older adults with MCI. In addition, have positive effects on improving executive function (Trial-Making Test A: MD = -2.37;95% CI:[-4.16, -0.58]; p = 0.010; Trial-Making Test B: MD = -16.0; 95% CI: [-30.03, -2.11]; p = 0.020) and immediate recall ability (SMD = 0.24;95% CI: [0.01, 0.46]; p = 0.04).

CONCLUSION

Aerobic dance significantly improves global cognitive function and memory in older adults with MCI. In addition, it also benefits executive function. However, due to the limitations as the review states, more randomized controlled trials with better study design and larger sample sizes should be conducted in the future research to make it much clearer.

Evidence of Effect of Aerobic Exercise on Cognitive Intervention in Older Adults With Mild Cognitive Impairment

This study aimed to evaluate the effectiveness of aerobic exercise as a cognitive intervention for older adults with mild cognitive impairment (MCI). The PubMed, EMBASE (Ovid), Cochrane Library, Web of Science, and Medline databases were searched from their inception until 30 April 2021. Randomized controlled trials (RCTs) examining the effects of aerobic exercise on global cognitive function in older adults with MCI were included. Ten eligible trials with acceptable methodological quality were identified. The meta-analysis results showed that aerobic exercise significantly improved the MMSE (N = 956, MD = 0.60, 95% CI: 0.28-0.92, p = 0.0003, I 2 = 31%, fixed effects model) and MoCA scores (N = 398, MD = 1.67, 95% CI. 1.18-2.15, p < 0.0001, I 2 = 37%, fixed-effects model) and overall cognitive performance in patients with MCI. The results of this study suggest that participation in regular aerobic exercise can improve cognitive function in older adults with MCI. These findings should be used with caution considering the limitations of the study.

Impact of various intensities and frequencies of non-occupational physical activity on the risk of dementia among physically independent older adults: the Japan Gerontological Evaluation Study

OBJECTIVES

The aim of this study was to investigate the association between different intensities and frequencies of non-occupational physical activity (PA) and the risk of dementia among Japanese older adults.

STUDY DESIGN

This was a prospective cohort study.

METHODS

A total of 2194 participants aged ≥65 years from the Japan Gerontological Evaluation Study were followed up between 2010 and 2016. The standardised dementia scale of the long-term care insurance system was used to identify incident dementia, whereas non-occupational PA (<2 or ≥2 times/week on each intensity: light, moderate and vigorous) was assessed using a questionnaire. Cox regression was used to compute the hazard ratios (HRs) and 95% confidence intervals (CIs) for incident dementia.

RESULTS

After adjustment for sociodemographic and medical characteristics, the following frequencies and intensities of non-occupational PA, compared with no non-occupational PA at all, were associated with a reduced risk of dementia: light PA ≥2 times/week (HR = 0.61, 95% CI: 0.38-0.97), moderate PA <2 times/week (HR = 0.46, 95% CI: 0.28-0.76), moderate PA ≥2 times/week (HR = 0.57, 95% CI: 0.36-0.91), vigorous PA <2 times/week (HR = 0.40, 95% CI: 0.21-0.74) and vigorous PA ≥2 times/week (HR = 0.29, 95% CI: 0.15-0.57). In the sex-specific analysis, moderate PA <2 times/week and vigorous PA ≥2 times/week were associated with a reduced risk of dementia in men, whereas light and moderate PA ≥2 times/week and all frequencies of vigorous PA were associated with a reduced risk of dementia in women.

CONCLUSIONS

Practicing non-occupational PA was associated with a reduced risk of dementia among Japanese older adults.

How can dementia and disability be prevented in older adults: where are we today and where are we going?

Ageing of the population, together with population growth, has brought along an ample increase in the number of older individuals living with dementia and disabilities. Dementia is the main cause of disability in old age, and promoting healthy brain ageing is considered as a key element in diminishing the burden of age-related disabilities. The World Health Organization recently launched the first risk reduction guidelines for cognitive impairment and dementia. According to recent estimates, approximately 40% of dementia cases worldwide could be attributable to 12 modifiable risk factors: low education; midlife hypertension and obesity; diabetes, smoking, excessive alcohol use, physical inactivity, depression, low social contact, hearing loss, traumatic brain injury and air pollution indicating clear prevention potential. Dementia and physical disability are closely linked with shared risk factors and possible shared underlying mechanisms supporting the possibility of integrated preventive interventions. FINGER trial was the first large randomized controlled trial indicating that multidomain lifestyle-based intervention can prevent cognitive and functional decline amongst at-risk older adults from the general population. Within the World-Wide FINGERS network, the multidomain FINGER concept is now tested and adapted worldwide proving evidence and tools for effective and easily implementable preventive strategies. Close collaboration between researchers, policymakers and healthcare practitioners, involvement of older adults and utilization of new technologies to support self-management is needed to facilitate the implementation of the research findings. In this scoping review, we present the current scientific evidence in the field of dementia and disability prevention and discuss future directions in the field.

Physical, Cognitive and Social Rehabilitation in Relation to Sleep Quality and Cognitive Functions in the Elderly

The aim of the study was to assess cognitive functions and sleep quality after a 3-month holistic intervention including physical, social and cognitive rehabilitation in patients 65+. Twenty-nine people participated in the study. The study was divided into two stages. In the first stage, a self-administered questionnaire consisting of sociodemographic questions was used, and cognitive functions were assessed using the Rey-Osterrieth complex figure test, Addenbrooke's Cognitive Examination III (ACE III) test, Montreal Cognitive Function Assessment Scale (MoCA) and digit repetition test. All patients were also assessed for sleep quality using the Athens Insomnia Scale (AIS). After three months, the patients were assessed for cognitive functions and sleep quality, which was the second stage of the study. Analysis of the results obtained by patients in the study showed a statistically significant improvement in sleep quality and cognitive function. Rehabilitation activities, including physical training, cognitive exercises and occupational therapy, reduce the severity of mild cognitive disorders and reduce insomnia.

Active Travel and Mild Cognitive Impairment among Older Adults from Low- and Middle-Income Countries

Active travel may be an easily achievable form of physical activity for older people especially in low- and middle-income countries (LMICs), but there are currently no studies on how this form of physical activity is associated with a preclinical state of dementia known as mild cognitive impairment (MCI). Therefore, we aimed to investigate the association between active travel and MCI among adults aged ≥50 years from six LMICs. Cross-sectional, community-based data from the World Health Organization’s Study on Global Ageing and Adult Health were analyzed. The definition of MCI was based on the National Institute on Ageing-Alzheimer’s Association criteria. Active travel (minutes/week) was assessed with questions of the Global Physical Activity Questionnaire (GPAQ) and presented in tertiles. Multivariable logistic regression analysis was conducted to assess the association between active travel and MCI. Data on 32715 people aged ≥50 years (mean age 62.4 years; 52.1% females) were analyzed. Compared to the highest tertile of active travel, the lowest tertile was associated with 1.33 (95%CI = 1.14–1.54) times higher odds for MCI overall. This association was particularly pronounced among those aged ≥65 years (OR = 1.70; 95%CI = 1.32–2.19) but active travel was not associated with MCI among those aged 50–64 years. In conclusion, low levels of active travel were associated with a significantly higher odds of MCI in adults aged ≥65 years in LMICs. Promoting active travel among people of this age group in LMICs via tailored interventions and/or country-wide infrastructure investment to provide a safe environment for active travel may lead to a reduction in MCI and subsequent dementia.

Current Evidence of Measurement Properties of Physical Activity Questionnaires for Older Adults: An Updated Systematic Review

BACKGROUND

Questionnaires provide valuable information about physical activity (PA) behaviors in older adults. Until now, no firm recommendations for the most qualified questionnaires for older adults have been provided.

OBJECTIVES

This review is an update of a previous systematic review, published in 2010, and aims to summarize, appraise and compare the measurement properties of all available self-administered questionnaires assessing PA in older adults.

METHODS

We included the articles evaluated in the previous review and conducted a new search in PubMed, Embase, and SPORTDiscus from September 2008 to December 2019, using the following inclusion criteria (1) the purpose of the study was to evaluate at least one measurement property (reliability, measurement error, hypothesis testing for construct validity, responsiveness) of a self-administered questionnaire; (2) the questionnaire intended to measure PA; (3) the questionnaire covered at least one domain of PA; (4) the study was performed in the general, healthy population of older adults; (5) the mean age of the study population was > 55 years; and (6) the article was published in English. Based on the Quality Assessment of Physical Activity Questionnaires (QAPAQ) checklist, we evaluated the quality and results of the studies. The content validity of all included questionnaires was also evaluated using the reviewers' rating. The quality of the body of evidence was evaluated for the overall construct of each questionnaire (e.g., total PA), moderate-to-vigorous physical activity (MVPA) and walking using a modified Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) approach.

RESULTS

In total, 56 articles on 40 different questionnaires (14 from the previous review and 26 from the update) were included. Reliability was assessed for 22, measurement error for four and hypotheses testing for construct validity for 38 different questionnaires. Evidence for responsiveness was available for one questionnaire. For many questionnaires, only one measurement property was assessed in only a single study. Sufficient content validity was considered for 22 questionnaires. All questionnaires displayed large measurement errors. Only versions of two questionnaires showed both sufficient reliability and hypotheses testing for construct validity, namely the Physical Activity Scale for the Elderly (PASE; English version, Turkish version) for the assessment of total PA, and the Physical Activity and Sedentary Behavior Questionnaire (PASB-Q; English version) for the assessment of MVPA. The quality of evidence for these results ranged from very low to high.

CONCLUSIONS

Until more high-quality evidence is available, we recommend the PASE for measuring total PA and the PASB-Q for measuring MVPA in older adults. However, they are not equally qualified among different languages. Future studies on the most promising questionnaires should cover all relevant measurement properties. We recommend using and improving existing PA questionnaires-instead of developing new ones-and considering the strengths and weaknesses of each PA measurement instrument for a particular purpose.

Association of physical activity and sedentary time with structural brain networks-The Maastricht Study

We assessed whether objectively measured low- and high-intensity physical activity (LPA and HPA) and sedentary time (ST) were associated with white matter connectivity, both throughout the whole brain and in brain regions involved in motor function. In the large population-based Maastricht Study (n = 1715, age 59.6 ± 8.1 (mean ± standard deviation) years, and 48% women), the amounts of LPA, HPA, and ST were objectively measured during 7 days by an activPAL accelerometer. In addition, using 3T structural and diffusion MRI, we calculated whole brain node degree and node degree of the basal ganglia and primary motor cortex. Multivariable linear regression analysis was performed, and we report standardized regression coefficients (stβ) adjusted for age, sex, education level, wake time, diabetes status, BMI, office systolic blood pressure, antihypertensive medication, total-cholesterol-to-HDL-cholesterol ratio, lipid-modifying medication, alcohol use, smoking status, and history of cardiovascular disease. Lower HPA was associated with lower whole brain node degree after full adjustment (stβ [95%CI] = - 0.062 [- 0.101, - 0.013]; p = 0.014), whereas lower LPA (stβ [95%CI] = - 0.013 [- 0.061, 0.034]; p = 0.580) and higher ST (stβ [95%CI] = - 0.030 [- 0.081, 0.021]; p = 0.250) was not. In addition, lower HPA was associated with lower node degree of the basal ganglia after full adjustment (stβ [95%CI] = - 0.070 [- 0.121, - 0.018]; p = 0.009). Objectively measured lower HPA, but not lower LPA and higher ST, was associated with lower whole brain node degree and node degree in specific brain regions highly specialized in motor function. Further research is needed to establish whether more HPA may preserve structural brain connectivity.