Effects of physical activity and exercise on the cognitive function of patients with Alzheimer disease: a meta-analysis

Therapeutic potential of exercise-hormone irisin in Alzheimer's disease

Irisin is a myokine that is generated by cleavage of the membrane protein fibronectin type III domain-containing protein 5 (FNDC5) in response to physical exercise. Studies reveal that irisin/FNDC5 has neuroprotective functions against Alzheimer's disease, the most common form of dementia in the elderly, by improving cognitive function and reducing amyloid-β and tau pathologies as well as neuroinflammation in cell culture or animal models of Alzheimer's disease. Although current and ongoing studies on irisin/FNDC5 show promising results, further mechanistic studies are required to clarify its potential as a meaningful therapeutic target for alleviating Alzheimer's disease. We recently found that irisin treatment reduces amyloid-β pathology by increasing the activity/levels of amyloid-β-degrading enzyme neprilysin secreted from astrocytes. Herein, we present an overview of irisin/FNDC5's protective roles and mechanisms against Alzheimer's disease.

Efficacy of exercise rehabilitation for managing patients with Alzheimer's disease

Alzheimer's disease (AD) is a progressive and degenerative neurological disease characterized by the deterioration of cognitive functions. While a definitive cure and optimal medication to impede disease progression are currently unavailable, a plethora of studies have highlighted the potential advantages of exercise rehabilitation for managing this condition. Those studies show that exercise rehabilitation can enhance cognitive function and improve the quality of life for individuals affected by AD. Therefore, exercise rehabilitation has been regarded as one of the most important strategies for managing patients with AD. Herein, we provide a comprehensive analysis of the currently available findings on exercise rehabilitation in patients with AD, with a focus on the exercise types which have shown efficacy when implemented alone or combined with other treatment methods, as well as the potential mechanisms underlying these positive effects. Specifically, we explain how exercise may improve the brain microenvironment and neuronal plasticity. In conclusion, exercise is a cost-effective intervention to enhance cognitive performance and improve quality of life in patients with mild to moderate cognitive dysfunction. Therefore, it can potentially become both a physical activity and a tailored intervention. This review may aid the development of more effective and individualized treatment strategies to address the challenges imposed by this debilitating disease, especially in low- and middle-income countries.

Inhibition of the mitochondrial pyruvate carrier in astrocytes reduces amyloid and tau accumulation in the 3xTgAD mouse model of Alzheimer's disease

Alzheimer's Disease (AD) is characterized by an accumulation of pathologic amyloid-beta (Aβ) and Tau proteins, neuroinflammation, metabolic changes and neuronal death. Reactive astrocytes participate in these pathophysiological processes by releasing pro-inflammatory molecules and recruiting the immune system, which further reinforces inflammation and contributes to neuronal death. Besides these neurotoxic effects, astrocytes can protect neurons by providing them with high amounts of lactate as energy fuel. Astrocytes rely on aerobic glycolysis to generate lactate by reducing pyruvate, the end product of glycolysis, through lactate dehydrogenase. Consequently, limited amounts of pyruvate enter astrocytic mitochondria through the Mitochondrial Pyruvate Carrier (MPC) to be oxidized. The MPC is a heterodimer composed of two subunits MPC1 and MPC2, the function of which in astrocytes has been poorly investigated. Here, we analyzed the role of the MPC in the pathogeny of AD, knowing that a reduction in overall glucose metabolism has been associated with a drop in cognitive performances and an accumulation of Aβ and Tau. We generated 3xTgAD mice in which MPC1 was knocked-out in astrocytes specifically and focused our study on the biochemical hallmarks of the disease, mainly Aβ and neurofibrillary tangle production. We show that inhibition of the MPC before the onset of the disease significantly reduces the quantity of Aβ and Tau aggregates in the brain of 3xTgAD mice, suggesting that acting on astrocytic glucose metabolism early on could hinder the progression of the disease.

Effects of Aerobic Exercise on Executive and Memory Functions in Patients With Alzheimer's Disease: A Systematic Review

BACKGROUND

Alzheimer's disease threatens the health of older adults, particularly by disrupting executive and memory functions, and many studies have shown that aerobic exercise prevents and improves the symptoms associated with the disease.

OBJECTIVE

The objective was to systematically review the effects of aerobic exercise on executive and memory functions in patients with Alzheimer's disease and to determine the effect factors and mechanisms of the design of aerobic exercise intervention programs.

METHOD

Relevant literature was searched in three databases (PubMed, Web of Science, and EBSCO) from January 1, 2014 to March 1, 2023, using a subject-word search method. Data on 10 items, including author and country, were extracted from the literature after screening. The quality of the literature was evaluated using the Physiotherapy Evidence Database scale, and a systematic review was performed.

RESULTS

Twelve papers from seven countries were ultimately included, embodying 11 randomized controlled trials and one study with a repeated-measures design. The overall quality of the studies was good as 657 study participants, aged 45 years and older who had varying degrees of Alzheimer's disease and significant symptoms, were included. Aerobic exercise was found to have a significant positive impact on executive and memory functions in people with Alzheimer's disease.

CONCLUSION

The effects of aerobic exercise on aspects of executive function were mainly characterized by improvements in inhibitory control, working memory, and cognitive flexibility, whereas the effects on aspects of memory function were mainly characterized by improvements in logical memory, situational memory, and short-term memory.

The interactions between energy homeostasis and neurovascular plasticity

Food intake and energy expenditure are sensed and processed by multiple brain centres to uphold energy homeostasis. Evidence from the past decade points to the brain vasculature as a new critical player in regulating energy balance that functions in close association with the local neuronal networks. Nutritional imbalances alter many properties of the neurovascular system (such as neurovascular coupling and blood-brain barrier permeability), thus suggesting a bidirectional link between the nutritional milieu and neurovascular health. Increasing numbers of people are consuming a Western diet (comprising ultra-processed food with high-fat and high-sugar content) and have a sedentary lifestyle, with these factors contributing to the current obesity epidemic. Emerging pharmacological interventions (for example, glucagon-like peptide 1 receptor agonists) successfully trigger weight loss. However, whether these approaches can reverse the detrimental effects of long-term exposure to the Western diet (such as neurovascular uncoupling, neuroinflammation and blood-brain barrier disruption) and maintain stable body weight in the long-term needs to be clarified in addition to possible adverse effects. Lifestyle interventions revert the nutritional trigger for obesity and positively affect our overall health, including the cardiovascular system. This Perspective examines how lifestyle interventions affect the neurovascular system and neuronal networks.

A review of the application of exercise intervention on improving cognition in patients with Alzheimer's disease: mechanisms and clinical studies

Alzheimer's disease (AD) is the most common form of dementia, leading to sustained cognitive decline. An increasing number of studies suggest that exercise is an effective strategy to promote the improvement of cognition in AD. Mechanisms of the benefits of exercise intervention on cognitive function may include modulation of vascular factors by affecting cardiovascular risk factors, regulating cardiorespiratory health, and enhancing cerebral blood flow. Exercise also promotes neurogenesis by stimulating neurotrophic factors, affecting neuroplasticity in the brain. Additionally, regular exercise improves the neuropathological characteristics of AD by improving mitochondrial function, and the brain redox status. More and more attention has been paid to the effect of Aβ and tau pathology as well as sleep disorders on cognitive function in persons diagnosed with AD. Besides, there are various forms of exercise intervention in cognitive improvement in patients with AD, including aerobic exercise, resistance exercise, and multi-component exercise. Consequently, the purpose of this review is to summarize the findings of the mechanisms of exercise intervention on cognitive function in patients with AD, and also discuss the application of different exercise interventions in cognitive impairment in AD to provide a theoretical basis and reference for the selection of exercise intervention in cognitive rehabilitation in AD.

Optimal dose and type of non-pharmacological treatments to improve cognitive function in people with Alzheimer's disease: a systematic review and network meta-analysis

OBJECTIVES

To evaluate and rank the effectiveness of specific non-pharmacological treatments (NPTs) in improving the global cognitive function in individuals with Alzheimer's disease (AD) and to examine the dose-response relationship.

METHOD

We conducted a systematic search in PubMed, MEDLINE, Embase, PsycINFO, CENTRAL, WOS, and CNKI from their inception to 15 February 2023. Standardized mean differences (SMD) and 95% confidence intervals (CI) were calculated for outcomes using random effects models.

RESULTS

We included 68 studies involving 5053 participants in this meta-analysis. The treatments with the highest cumulative probabilities for improving global cognitive function were transcranial direct current stimulation (tDCS), followed by physical exercise (PE), and repetitive transcranial magnetic stimulation (rTMS). Additionally, cognitive stimulation (CS), cognitive training CT), multidisciplinary program (MD), and reminiscence treatment (RT) also significantly improve the global cognitive function of people with AD. A non-linear dose-response association was observed for tDCS, PE, rTMS, CS, and CT with global cognitive improvement. Notably, no minimal threshold was identified for the beneficial effects of PE on cognition. The estimated minimal doses for clinically relevant changes in cognition were 33 min per week for tDCS, 330 MET-min per week for PE, and 8000 pulses per week for rTMS.

CONCLUSION

tDCS, PE, and rTMS are the better effective NPTs for enhancing global cognitive function in individuals with AD. Properly dosing these treatments can yield significant clinical benefits. Our findings support the clinical utility of low-dose exercise in improving cognition in people with AD.

The Alzheimer's patients interaction through digital and arts (AIDA) program: A feasibility study to improve wellbeing in people with Alzheimer's disease

Alzheimer's disease (AD) presents a growing global challenge, with an increasing prevalence and significant impact on individuals and public health. Effective pharmacological treatments directly impacting the disease are still lacking, highlighting the importance of programs and interventions aimed at improving the wellbeing of those affected. The present feasibility study aimed to evaluate the effectiveness and feasibility of the Alzheimer's patients Interaction through Digital and Arts (AIDA) program. AIDA's main objective is to enhance perceived wellbeing and quality of life of people with AD and their caregivers through a series of structured activities through museum- and art-based activities over five sessions. Pre- and post-program evaluations were conducted using Visual Analog Scales (VASs) to measure various dimensions of perceived wellbeing such as confidence, happiness, interest, optimism, and wellness. Results showed significant improvements in all considered dimensions for people with AD following AIDA activities, highlighting its potential to enhance overall wellbeing. Caregivers also reported increased perceived wellness post-program, demonstrating some positive effects also in healthy participants. The feasibility of AIDA was supported by positive feedback and engagement of participants. Overall, the AIDA program offers a non-intrusive and engaging approach to improve the perceived wellbeing of people with AD and caregivers while facilitating meaningful experiences (e.g., silence, sharing etc.) in cultural settings.

Irisin Levels in Cerebrospinal Fluid Correlate with Biomarkers and Clinical Dementia Scores in Alzheimer Disease

OBJECTIVE

Irisin, released by muscles during exercise, was recently identified as a neuroprotective factor in mouse models of Alzheimer disease (AD). In a cohort of AD patients, we studied cerebrospinal fluid (CSF) and plasma irisin levels, sex interactions, and correlations with disease biomarkers.

METHODS

Correlations between CSF and plasma irisin levels and AD biomarkers (amyloid β 1-42, hyperphosphorylated tau, and total tau [t-tau]) and Clinical Dementia Rating Scale Sum of Boxes (CDR-SOB) were analyzed in a cohort of patients with Alzheimer dementia (n = 82), mild cognitive impairment (n = 44), and subjective memory complaint (n = 20) biologically characterized according to the recent amyloid/tau/neurodegeneration classification.

RESULTS

CSF irisin was reduced in Alzheimer dementia patients (p < 0.0001), with lower levels in female patients. Moreover, CSF irisin correlated positively with Aβ42 in both female (r = 0.379, p < 0.001) and male (r = 0.262, p < 0.05) patients, and negatively with CDR-SOB (r = -0.234, p < 0.05) only in female patients. A negative trend was also observed between CSF irisin and t-tau levels in all patients (r = -0.144, p = 0.082) and in the female subgroup (r = -0.189, p = 0.084).

INTERPRETATION

The results highlight the relationship between irisin and biomarkers of AD pathology, especially in females. Our findings also offer perspectives toward the use of irisin as a marker of the AD continuum. ANN NEUROL 2024;96:61-73.

Comparison of the effect of online physical exercise and computerized cognitive stimulation in patients with Alzheimer's disease during the Covid-19 pandemic

INTRODUCTION

To investigate the effect of physical exercise alone and in combination with cognitive stimulation on cognition, physical function, and quality of life in patients with Alzheimer's Disease (PwAD).

METHODS

The study was a randomized controlled, single-blinded trial with pre-and post-treatment and follow-up assessments conducted at the private hospital and home environment in PwAD. Seventy-five (N = 75) participants diagnosed with AD were enrolled, but sixty (N = 60) participants (mean age 77.8 years, standard deviation (SD) 6.7) were randomized as physical exercise group (PEG) (n = 20), physical exercise and cognitive stimulation group (PE + CSG) (n = 20) and control group (CG) (n = 20). Participants in PEG and PE + CSG performed an online supervised physical exercise program (SPEP) given biweekly for 12 weeks. Additionally, the cognitive stimulation (CS) program was offered for at least three or five days for 12 weeks for PE + CSG. No treatment was given for the CG. The primary outcome measures were cognition, balance, functional mobility (FM), upper extremity muscle strength (UEMS) and lower extremity muscle strength (LEMS), and quality of life (QoL). Furthermore, depression, basic activities of daily living (BADL) and instrumental activities of daily living (IADL) were measured secondarily.

RESULTS

PE + CSG demonstrated significant improvement in cognition, balance, FM, UEMS, IADL and reduction in depression compared to the CG (p < 0.05). Besides, participants in the PE + CSG had statistically superior QoL and IADL than the PEG (p < 0.05).

CONCLUSIONS

The addition of CS to the SPEP was a safe and effective method to gain statistically significant improvements in cognition, balance, FM, UEMS, IADL, and reduction in depression in PwAD.

Evidence mapping and quality assessment of systematic reviews on exercise intervention for Alzheimer's disease

BACKGROUND

A significant body of literature suggests that exercise can reverse cognitive impairment and ameliorate somatic function in patients with Alzheimer's disease (AD). Systematic reviews (SRs), a common approach of evidence-based medicine, concentrate on a specific issue of a research area. The objective of this work is to provide an overview of existing evidence on the effects of exercise intervention in AD patients and report related health outcomes by reviewing SRs.

METHODS

SRs on exercise intervention in AD patients were retrieved from the PubMed, the Cochrane Library, CBMdisc, Scopus, Web of Science, Embase (via Ovid), China National Knowledge Infrastructure, and WanFang databases from the time of inception to February 2023. The quality of the SRs was evaluated utilizing the A Measurement Tool to Assess Systematic Review 2 (AMSTAR 2) checklist. The results were reported according to the population-intervention-comparison-outcome (PICO) framework and the corresponding evidence mapping was illustrated in tables and bubble plots.

RESULTS

A total of 26 SRs met the eligibility criteria. In terms of methodological quality, 10 SRs were rated as "critically low", 13 SRs were rated as "low", and 3 SRs were rated as "moderate". Exercise was found to exert a beneficial effect on cognitive function, functional independence, physical function, and neuropsychiatric symptoms in patients with AD.

CONCLUSION

Exercise intervention benefits AD patients mainly by improving cognitive function, physical function, functional independence, and neuropsychiatric symptoms. However, due to the low-to-moderate methodology of most SRs included in this analysis, further investigations are required to support our current findings.

Exercise to Counteract Alzheimer's Disease: What Do Fluid Biomarkers Say?

Neurodegenerative diseases (NDs) represent an unsolved problem to date with an ever-increasing population incidence. Particularly, Alzheimer's disease (AD) is the most widespread ND characterized by an accumulation of amyloid aggregates of beta-amyloid (Aβ) and Tau proteins that lead to neuronal death and subsequent cognitive decline. Although neuroimaging techniques are needed to diagnose AD, the investigation of biomarkers within body fluids could provide important information on neurodegeneration. Indeed, as there is no definitive solution for AD, the monitoring of these biomarkers is of strategic importance as they are useful for both diagnosing AD and assessing the progression of the neurodegenerative state. In this context, exercise is known to be an effective non-pharmacological management strategy for AD that can counteract cognitive decline and neurodegeneration. However, investigation of the concentration of fluid biomarkers in AD patients undergoing exercise protocols has led to unclear and often conflicting results, suggesting the need to clarify the role of exercise in modulating fluid biomarkers in AD. Therefore, this critical literature review aims to gather evidence on the main fluid biomarkers of AD and the modulatory effects of exercise to clarify the efficacy and usefulness of this non-pharmacological strategy in counteracting neurodegeneration in AD.

Exergaming and cognitive functions in people with mild cognitive impairment and dementia: a meta-analysis

Exergaming is a combination of exercise and gaming. Evidence shows an association between exercise and cognition in older people. However, previous studies showed inconsistent results on the cognitive benefits of exergaming in people with cognitive impairment. Therefore, this study aims to examine the effect of exergaming intervention on cognitive functions in people with MCI or dementia. A systematic literature search was conducted via OVID databases. Randomized controlled trials (RCTs) examined the effect of an exergaming intervention on cognitive functions in people with MCI or dementia were included. Subgroup analyses were conducted according to the type of intervention and training duration. Twenty RCTs with 1152 participants were identified, including 14 trials for MCI and 6 trials for dementia. In people with MCI, 13 studies used virtual-reality (VR)-based exergaming. Those who received VR-based exergaming showed significantly better global cognitive function [SMD (95%CI) = 0.67 (0.23-1.11)], learning and memory [immediate recall test: 0.79 (0.31-1.27); delayed recall test: 0.75 (0.20-1.31)], working memory [5.83 (2.27-9.39)], verbal fluency [0.58 (0.12-1.03)], and faster in executive function than the controls. For people with dementia, all studies used video-based exergaming intervention. Participants with exergaming intervention showed significantly better global cognitive function than the controls [0.38 (0.10-0.67)]. Subgroup analyses showed that longer training duration generated larger effects. The findings suggest that exergaming impacts cognitive functions in people with MCI and dementia. Cognitive benefits are demonstrated for those with a longer training duration. With technological advancement, VR-based exergaming attracts the attention of people with MCI and performs well in improving cognitive functions.

Correlation between hearing loss and mild cognitive impairment in the elderly population: Mendelian randomization and cross-sectional study

Background

Hearing loss and tinnitus have been linked to mild cognitive impairment (MCI); however, the evidence is constrained by ethical and temporal constraints, and few prospective studies have definitively established causation. This study aims to utilize Mendelian randomization (MR) and cross-sectional studies to validate and analyze this association.

Methods

This study employs a two-step approach. Initially, the genetic data of the European population from the Genome-wide association studies (GWAS) database is utilized to establish the causal relationship between hearing loss and cognitive impairment through Mendelian randomization using the inverse variance weighted (IVW) method. This is achieved by identifying strongly correlated single nucleotide polymorphisms (SNPs), eliminating linkage disequilibrium, and excluding weak instrumental variables. In the second step, 363 elderly individuals from 10 communities in Qingdao, China are assessed and examined using methods questionnaire survey and pure tone audiology (PTA). Logistic regression and multiple linear regression were used to analyze the risk factors of MCI in the elderly and to calculate the cutoff values.

Results

Mendelian randomization studies have shown that hearing loss is a risk factor for MCI in European populations, with a risk ratio of hearing loss to MCI loss of 1. 23. The findings of this cross-sectional study indicate that age, tinnitus, and hearing loss emerged as significant risk factors for MCI in univariate logistic regression analysis. Furthermore, multivariate logistic regression analysis identified hearing loss and tinnitus as potential risk factors for MCI. Consistent results were observed in multiple linear regression analysis, revealing that hearing loss and age significantly influenced the development of MCI. Additionally, a notable finding was that the likelihood of MCI occurrence increased by 9% when the hearing threshold exceeded 20 decibels.

Conclusion

This study provides evidence from genomic and epidemiological investigations indicating that hearing loss may serve as a risk factor for cognitive impairment. While our epidemiological study has found both hearing loss and tinnitus as potential risk factors for cognitive decline, additional research is required to establish a causal relationship, particularly given that tinnitus can manifest as a symptom of various underlying medical conditions.

Dementia-Inclusive Choices for Exercise Toolkit: Impact on the Knowledge, Perspectives, and Practices of Exercise Providers

Physical activity improves the well-being of persons living with dementia but few exercise programs include them. The Dementia-Inclusive Choices for Exercise (DICE) toolkit aims to improve exercise providers' understanding of dementia and ability to support persons living with dementia in physical activity. We evaluated the co-designed DICE toolkit with exercise providers using a mixed-methods approach comprising pre/post questionnaires and interviews and reflection diaries. Among 16 participants, self-efficacy for exercise delivery to persons living with dementia and both knowledge and attitudes toward dementia significantly improved. Thematic analysis suggested participants (a) had a deeper understanding of the variability of dementia, (b) were planning for equitable access for persons living with dementia, (c) planned to promote social connection through exercise, and (d) were optimistic for future engagement with persons living with dementia. The DICE toolkit may improve exercise providers' knowledge and confidence to plan proactively to support persons living with dementia in programs and services.

Mechanistic insights and emerging therapeutic stratagems for Alzheimer's disease

Alzheimer's disease (AD), a multi-factorial neurodegenerative disorder has affected over 30 million individuals globally and these numbers are expected to increase in the coming decades. Current therapeutic interventions are largely ineffective as they focus on a single target. Development of an effective drug therapy requires a deep understanding of the various factors influencing the onset and progression of the disease. Aging and genetic factors exert a major influence on the development of AD. Other factors like post-viral infections, iron overload, gut dysbiosis, and vascular dysfunction also exacerbate the onset and progression of AD. Further, post-translational modifications in tau, DRP1, CREB, and p65 proteins increase the disease severity through triggering mitochondrial dysfunction, synaptic loss, and differential interaction of amyloid beta with different receptors leading to impaired intracellular signalling. With advancements in neuroscience tools, new inter-relations that aggravate AD are being discovered including pre-existing diseases and exposure to other pathogens. Simultaneously, new therapeutic strategies involving modulation of gene expression through targeted delivery or modulation with light, harnessing the immune response to promote clearance of amyloid deposits, introduction of stem cells and extracellular vesicles to replace the destroyed neurons, exploring new therapeutic molecules from plant, marine and biological sources delivered in the free state or through nanoparticles and use of non-pharmacological interventions like music, transcranial stimulation and yoga. Polypharmacology approaches involving combination of therapeutic agents are also under active investigation for superior therapeutic outcomes. This review elaborates on various disease-causing factors, their underlying mechanisms, the inter-play between different disease-causing players, and emerging therapeutic options including those under clinical trials, for treatment of AD. The challenges involved in AD therapy and the way forward have also been discussed.

Molecular insights of exercise therapy in disease prevention and treatment

Despite substantial evidence emphasizing the pleiotropic benefits of exercise for the prevention and treatment of various diseases, the underlying biological mechanisms have not been fully elucidated. Several exercise benefits have been attributed to signaling molecules that are released in response to exercise by different tissues such as skeletal muscle, cardiac muscle, adipose, and liver tissue. These signaling molecules, which are collectively termed exerkines, form a heterogenous group of bioactive substances, mediating inter-organ crosstalk as well as structural and functional tissue adaption. Numerous scientific endeavors have focused on identifying and characterizing new biological mediators with such properties. Additionally, some investigations have focused on the molecular targets of exerkines and the cellular signaling cascades that trigger adaption processes. A detailed understanding of the tissue-specific downstream effects of exerkines is crucial to harness the health-related benefits mediated by exercise and improve targeted exercise programs in health and disease. Herein, we review the current in vivo evidence on exerkine-induced signal transduction across multiple target tissues and highlight the preventive and therapeutic value of exerkine signaling in various diseases. By emphasizing different aspects of exerkine research, we provide a comprehensive overview of (i) the molecular underpinnings of exerkine secretion, (ii) the receptor-dependent and receptor-independent signaling cascades mediating tissue adaption, and (iii) the clinical implications of these mechanisms in disease prevention and treatment.

Fostering emotional well-being in adolescents: the role of physical activity, emotional intelligence, and interpersonal forgiveness

Introduction

Adolescence is considered a stress-sensitive developmental period, and the escalating and sustained pressure during this phase poses a significant threat to the mental and physical well-being of adolescents. Therefore, enhancing positive emotions in adolescents is crucial. This study aims to investigate the impact of physical activity on the emotional intelligence, interpersonal forgiveness, and positive emotions of adolescents.

Methods

Using a cluster sampling method, data were collected from 500 adolescents in four schools across the Xiangxi Tujia and Miao Autonomous Prefecture of Hunan Province, China. A total of 428 valid questionnaires were collected and analyzed. The study employed AMOS v.23 to construct a structural equation model to validate the hypotheses.

Results

The results indicate that physical activity significantly influences the emotional intelligence, interpersonal forgiveness, and positive emotions of adolescents. Furthermore, emotional intelligence and interpersonal forgiveness mediate the relationship between physical activity and positive emotions.

Discussion

Based on these findings, collaborative efforts from government agencies, schools, and families are essential to provide robust support for adolescents' participation in physical activity, encouraging more adolescents to actively engage in sports.

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.

Systematic evaluation and meta-analysis of the effects of major dietary patterns on cognitive function in healthy adults

PURPOSE

Evidence shows diet promotes brain health. Combining foods and nutrients may have beneficial synergistic effects, but the effects on cognitive function interventions are inconsistent. So, a meta-analysis of RCTs was conducted to examine the specific effects on cognitive function.

METHODS

We searched four databases from creation to April 2023. Eligible randomized controlled trials were identified. A random-effects meta-analysis was used to combine standardized mean differences (SMD) (95% confidence intervals [CI]), and homogeneity tests for a variance were calculated.

RESULTS

A total of 19 studies involving 12,119 participants were included in this systematic review. The dietary intervention group had a positive effect on overall cognitive functioning compared to the control group (SMD = 0.14, 95% CI [0.08, 0.20], P < 0.00001). The dietary intervention improved executive function, processing speed and language skills (SMD = -0.10, 95% CI [-0.17,-0.04], P = 0.002, I2 = 0%), (SMD = -0.16, 95% CI [-0.23,-0.09], P < 0.00001, I2 = 0%), (SMD = 0.10, 95% CI [0.01, 0.20], P = 0.03, I2 = 0%). The dietary intervention had no effect on delayed memory and spatial ability (SMD = 0.04, 95% CI [-0.02, 0.09], P = 0.20, I2 = 0%), (SMD = 0.08, 95% CI [-0.01, 0.16], P = 0.08, I2 = 0%).

CONCLUSION

The Mediterranean diet, a diet with restricted caloric intake, a diet incorporating aerobic exercise, a low-carbohydrate diet, and a healthy lifestyle diet (increased intake of fruits and vegetables, and weight and blood pressure management) appear to have positive effects on cognitively healthy adults, as reflected in their overall cognitive, processing speed, executive, and language functions.

PROSPERO REGISTRATION NUMBER

CRD42023414704.

Effects of different exercise interventions on chemotherapy-related cognitive impairment in patients with breast cancer: a study protocol for systematic review and network meta-analysis

INTRODUCTION

Breast cancer stands as the most prevalent type of cancer affecting women globally, and chemotherapy plays a pivotal role in its treatment by diminishing tumour recurrence and enhancing the survival rates of patients. However, chemotherapy-related cognitive impairment (CRCI) often occurs in patients undergoing treatment. Although multiple clinical trials have indicated that exercise therapy can improve CRCI in patients with breast cancer, there are variations in the types of exercise interventions and their effectiveness. We aim to perform a pioneering network meta-analysis (NMA) to assess and prioritise the effectiveness of various exercise interventions in enhancing cognitive function in patients with breast cancer undergoing chemotherapy.

METHODS AND ANALYSIS

We will search multiple databases, including PubMed, Web of Science, Cochrane, Embase, China National Knowledge Infrastructure, VIP Database for Chinese Technical Periodicals, Wanfang and Sinomed databases, from their inception to May 2023. The main outcome is the cognitive function changes in patients with breast cancer, including subjective and objective results. We will specifically include randomised controlled trials reported in English and Chinese languages, whose primary outcome consists of an assessment of the cognitive function of patients with breast cancer using standardised and validated assessment tools, encompassing both subjective and objective outcomes. The quality of all the trials included will be evaluated based on 'Version 2 of the Cochrane tool for assessing the risk of bias in randomized controlled trials (RoB2)'. We will conduct a Bayesian NMA to thoroughly evaluate and compare the effectiveness of different exercise interventions. We will use cumulative ranking probability plots to estimate the ranking of the best interventions for various exercises. Network plots and funnel plots will be employed to display the study sizes and participants of each exercise intervention, as well as potential publication biases.

ETHICS AND DISSEMINATION

The study findings will be shared via peer-reviewed journals to ensure the highest quality and credibility of the research. As the reporting will not include any private patient data, there are no ethical considerations associated with this protocol.

PROSPERO REGISTRATION NUMBER

CRD42023406597.

The newly discovered glymphatic system: the missing link between physical exercise and brain health?

Dementias are responsible for the most frequent neurodegenerative diseases and the seventh leading cause of death worldwide. As a result, there is a growing effort by the neuroscientific community to understand the physiopathology of neurodegenerative diseases, including how to alleviate the effects of the cognitive decline by means of non-pharmacological therapies (e.g., physical exercise). Studies have shown that exercise can improve aspects of brain health related to cognition. However, there still needs to be more knowledge regarding the mechanisms controlling these relationships, and a newly discovered cleansing system in the brain, named the glymphatic system, can be the missing link in this mechanism. The objective of this paper is to review recent findings regarding the potential impacts of physical exercise on the glymphatic system and its implications for the onset of neurodegenerative diseases. Additionally, considering the close interplay between exercise and sleep quality, we aim to explore how sleep patterns may intersect with exercise-induced effects on glymphatic function, further elucidating the complex relationship between lifestyle factors and brain health.

Associations between regular physical exercise and physical, emotional, and cognitive health of older adults in China: an 8-year longitudinal study with propensity score matching

Background

The importance of healthy aging is growing in China as it has the largest number of older adults in the world and is one of the fastest-aging countries. This study aimed to examine the predictive value of regular physical exercise in relation to the physical, emotional, and cognitive health among samples of adults aged ≥60 years in China during an 8-year period.

Methods

A total of 10,691 older adults were extracted from two waves of national data from the China Family Panel Studies in 2010 and 2018. To minimize the impact of selection bias on the findings, a longitudinal propensity score matching (LPSM) method was used to examine the relationships between regular physical exercise and emotional health (depression), between regular physical exercise and physical health (instrumental activities of daily living), and between regular physical exercise and cognitive health (cognitive ability) of older adults. After LPSM, 856 older adults were included in the study. In the regular physical exercise group, the average age of participants at baseline year was 65.67 years, with an average age of 65.90 years for 238 men and 65.45 years for 190 women, and in the non-physical exercise group, their average age at baseline year was 65.70 years, with an average age of 65.45 years for 253 men and 65.98 years for 175 women.

Results

LPSM indicated that regular physical exercise has been found to be effective in improving physical function and reducing depressive symptoms in old adults, even after controlling for background differences. However, the sensitivity analysis suggests that the positive association between regular physical exercise and cognitive function may not be sufficiently valid.

Conclusion

The findings of this study indicate that engaging in long-term structured and repetitive physical exercise can have a significant positive effect on reducing depressive symptoms and improving the physical function of older adults. As a result, incorporating regular physical exercise into the lifestyle of older adults is recognized as an effective strategy for promoting healthy aging and reducing the strain on public health resources.

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.

Contributing Factors for (Non)Adherence to a Physical Exercise Program for People With Neurocognitive Disorder From the Caregivers' Perspective

BACKGROUND AND PURPOSE

To explore the perception of informal caregivers about the barriers, motivators, and facilitators toward the participation of care recipients with neurocognitive disorder (NCD) in a physical exercise program.

METHODS

This is an exploratory qualitative study, including 20 informal caregivers (67.5 ± 13.94 years old; age range: 37-86; 65% male) from the "Body & Brain" community intervention project. Semistructured interviews were performed by a trained researcher; data analysis followed Braun and Clarke's thematic analysis guidelines, under the socioecological framework.

RESULTS

Two main barriers, 3 motivators, and 5 facilitators to participation in a physical exercise program were perceived by caregivers, illustrating the relationship between the intrapersonal, interpersonal, and community levels toward individuals' participation. Care recipients' reluctance to participate and physical environment constraints emerged as the main barriers to participation, whereas the health professionals' advice, the need for a stimulating activity, and the potential physical and mental health benefits emerged as motivators. Factors facilitating the involvement and maintenance in the program included care recipients' satisfaction and enjoyment, benefits on their general health, routine, and social connectedness; an overall positive evaluation of the physical exercise program's structure and organization was also highlighted.

CONCLUSIONS

Exercise interventions targeting people with NCD should promote a welcoming environment that facilitates individuals' well-being and social interaction. Caregivers have a key role in promoting care recipients' motivation. Health professionals play an important role in recommending participation by raising awareness of potential benefits to recipients and caregivers. Future interventions should be conducted in appropriate community settings and implemented by a specialized professional in small groups. These findings provide insights into the factors that may increase the success rate of exercise interventions specifically designed for individuals with NCD.

Physical Activity Moderates the Relationship between Cardiovascular Disease Risk Burden and Cognition in Older Adults

INTRODUCTION

Older individuals with a higher cardiovascular disease (CVD) burden have a higher risk for accelerated cognitive decline and dementia. Physical activity (PA) is an inexpensive and accessible preventive measure to CVD, cognitive impairment, and dementia. The current study examined (1) whether PA moderates the relationship between CVD burden and cognition and (2) whether the moderating effect of PA differs by race/ethnicity groups and by APOE-ɛ4 status.

METHODS

Our cross-sectional study included participants from the Washington Heights-Inwood Columbia Aging Project (WHICAP), a multiethnic, community-based, longitudinal study on aging and dementia among individuals aged 65 years and older who reside in northern Manhattan. All participants underwent an interview and a neuropsychological assessment for global cognition, memory, language, visuospatial, and speed functioning.

RESULTS

In 2,122 older individuals without dementia, having a higher CVD burden was associated with worse cognitive scores for global, language, speed, and visuospatial cognitive functions. PA mitigated the relationship between CVD burden and visuospatial function. Furthermore, PA mitigated the association of CVD burden with global cognition, language, and visuospatial functions in APOE-ɛ4 carriers but not in non-carriers.

DISCUSSION/CONCLUSION

Our study suggests that PA may mitigate the negative association between CVD and cognition, especially in APOE-ɛ4 carriers. The moderating effect of PA did not differ by race/ethnicity.

Physical exercise frequency and cognition: a multicenter cross-sectional cohort study

Background and aims

Dementia imposes a heavy burden on society and families, therefore, effective drug treatments, exploring and preventing factors associated with dementia, are paramount. To provide reference points for the best frequency of physical exercise (physical exercise), we investigated the association between frequency of PE and cognition in Chinese old adults.

Methods

16,181 Chinese participants aged 65 years or older were included in this study. Associations between PE and cognition were estimated multivariate logistic and linear regression analyses. Associations were further investigated across dementia subtypes (Alzheimer dementia, vascular dementia, and other types of dementia). Subgroup analyses were performed in different age groups, in populations with and without stroke, and those with and without hypertension.

Results

PE associated with dementia after adjusting for full covariates (OR: 0.5414, 95% CI: 0.4536-0.6491, p < 0.001). Exercise performed at ≥3 times/week associated with lower risk of dementia (OR: 0.4794-0.6619, all p value <0.001). PE was associated with improved cognition (β: 12851, p < 0.001), and any PE frequency contributed to cognitive improvement (p values for exercise performed ≥1 time/week were <0.001). Similar conclusions were identified when we repeated analyses in different dementia subtypes and age groups. Subgroup analyses suggested that the cognition of individuals without hypertension also benefitted from exercising 1-2 times/week (OR: 0.6168, 95% CI: 0.4379-0.8668, p = 0.005).

Conclusion

The best exercise frequency is exercising ≥3 times/week for individuals from different dementia subtypes and age groups. While for those without hypertension, PE at 1-2 times /week is also beneficial.

Using artificial intelligence for exercise prescription in personalised health promotion: A critical evaluation of OpenAI's GPT-4 model

The rise of artificial intelligence (AI) applications in healthcare provides new possibilities for personalized health management. AI-based fitness applications are becoming more common, facilitating the opportunity for individualised exercise prescription. However, the use of AI carries the risk of inadequate expert supervision, and the efficacy and validity of such applications have not been thoroughly investigated, particularly in the context of diverse health conditions. The aim of the study was to critically assess the efficacy of exercise prescriptions generated by OpenAI's Generative Pre-Trained Transformer 4 (GPT-4) model for five example patient profiles with diverse health conditions and fitness goals. Our focus was to assess the model's ability to generate exercise prescriptions based on a singular, initial interaction, akin to a typical user experience. The evaluation was conducted by leading experts in the field of exercise prescription. Five distinct scenarios were formulated, each representing a hypothetical individual with a specific health condition and fitness objective. Upon receiving details of each individual, the GPT-4 model was tasked with generating a 30-day exercise program. These AI-derived exercise programs were subsequently subjected to a thorough evaluation by experts in exercise prescription. The evaluation encompassed adherence to established principles of frequency, intensity, time, and exercise type; integration of perceived exertion levels; consideration for medication intake and the respective medical condition; and the extent of program individualization tailored to each hypothetical profile. The AI model could create general safety-conscious exercise programs for various scenarios. However, the AI-generated exercise prescriptions lacked precision in addressing individual health conditions and goals, often prioritizing excessive safety over the effectiveness of training. The AI-based approach aimed to ensure patient improvement through gradual increases in training load and intensity, but the model's potential to fine-tune its recommendations through ongoing interaction was not fully satisfying. AI technologies, in their current state, can serve as supplemental tools in exercise prescription, particularly in enhancing accessibility for individuals unable to access, often costly, professional advice. However, AI technologies are not yet recommended as a substitute for personalized, progressive, and health condition-specific prescriptions provided by healthcare and fitness professionals. Further research is needed to explore more interactive use of AI models and integration of real-time physiological feedback.

Integrating Lifestyle Factor Science into Neuropsychological Practice: A National Academy of Neuropsychology Education Paper

OBJECTIVE

The primary aim of this paper is to review evidence and clinical implications related to lifestyle activities associated with promoting brain and cognitive health. Our review targets four key lifestyle factors: physical activity and exercise, social engagement, cognitively stimulating activity, and consuming Mediterranean-style diets.

METHOD

We conducted a critical review of the lifestyle factor literature in the four domains listed earlier. We contextualize this literature review by translating findings, when possible, into evidence-based recommendations to consider when providing neuropsychological services.

RESULTS

There is significant current evidence supporting the role of physical activity and exercise, social engagement, cognitively stimulating activity, and consuming Mediterranean-style diets on positive brain and cognitive health outcomes. While some null findings are present in all four areas reviewed, the weight of the evidence supports the notion that engaging in these activities may promote brain and cognitive functioning.

CONCLUSIONS

Clinical neuropsychologists can have confidence in recommending engagement in physical activity, social activity, and cognitively stimulating activity, and adhering to a Mediterranean-style diet to promote brain and cognitive health. We discuss limitations in existing lifestyle factor research and future directions to enhance the existing evidence base, including additional research with historically underrepresented groups and individuals with neurological conditions.

New horizons in the diagnosis and management of Alzheimer's Disease in older adults

Alzheimer's Disease (ad) is the most common cause of dementia, and in addition to cognitive decline, it directly contributes to physical frailty, falls, incontinence, institutionalisation and polypharmacy in older adults. Increasing availability of clinically validated biomarkers including cerebrospinal fluid and positron emission tomography to assess both amyloid and tau pathology has led to a reconceptualisation of ad as a clinical-biological diagnosis, rather than one based purely on clinical phenotype. However, co-pathology is frequent in older adults which influence the accuracy of biomarker interpretation. Importantly, some older adults with positive amyloid or tau pathological biomarkers may never experience cognitive impairment or dementia. These strides towards achieving an accurate clinical-biological diagnosis are occurring alongside recent positive phase 3 trial results reporting statistically significant effects of anti-amyloid Disease-Modifying Therapies (DMTs) on disease severity in early ad. However, the real-world clinical benefit of these DMTs is not clear and concerns remain regarding how trial results will translate to real-world clinical populations, potential adverse effects (including amyloid-related imaging abnormalities), which can be severe and healthcare systems readiness to afford and deliver potential DMTs to appropriate populations. Here, we review recent advances in both clinical-biological diagnostic classification and future treatment in older adults living with ad. Advocating for access to both more accurate clinical-biological diagnosis and potential DMTs must be done so in a holistic and gerontologically attuned fashion, with geriatricians advocating for enhanced multi-component and multi-disciplinary care for all older adults with ad. This includes those across the ad severity spectrum including older adults potentially ineligible for emerging DMTs.

Comparative efficacy of various exercise interventions on sleep in patients with cognitive impairment: a systematic review and meta-analysis

Background

Sleep disturbances are an early indicator of cognitive impairment and exacerbate its progression. While pharmacological treatments for sleep disorders exist, their side-effect profile includes an increased risk of falls and the potential to exacerbate cognitive impairment. Non-pharmacological treatments such as physical exercise should be considered. However, uncertainties persist. We aimed to assess the potential benefits of exercise interventions on sleep in patients with cognitive impairment and determine the specific effects of various exercise modalities.

Materials and methods

A systematic search was performed on seven databases for eligible studies published before Nov 2022. Randomized controlled trials of exercise for patients with cognitive impairment (mild cognitive impairment and Alzheimer's disease) were included. All analyses were conducted using RevMan version 5.4. Meta-analysis and The Grading of Recommendations Assessment Development and Evaluations (GRADE) quality ratings were performed on sleep quality and objective sleep data.

Results

A total of 8 randomized controlled trials were included with a sample size of 486 subjects. For patients with cognitive impairment, physical exercise had a beneficial effect on sleep quality [MD = -3.55 (-5.57, -1.32), Z = 3.13, p = 0.002] and total sleep time [MD = 33.77 (23.92, 43.62), Z = 6.72, P < 0.00001]. No improvement was found in sleep efficiency and nocturnal awakening time. Subgroup analysis showed that multi-component exercise produced superior results.

Conclusion

Physical exercise may improve sleep quality and total sleep time for patients with cognitive impairment. Multi-component exercise designed individually is more effective. Large-scale randomized controlled trials with objective sleep outcome measurements are warranted.Clinical trial registration: https://www.crd.york.ac.uk/prospero/, identifier: CRD42022377221.

14-Week exercise training modifies the DNA methylation levels at gene sites in non-Alzheimer's disease women aged 50 to 70 years

Exercise training emerges as a key strategy in lifestyle modification, capable of reducing the risk of developing Alzheimer's disease (AD) due to risk factors such as age, family history, genetics and low level of education associated with AD. We aim to analyze the effect of a 14-week combined exercise training (CT) on the methylation of genes associated with AD in non-alzheimer's disease women. CT sessions lasted 60 min, occurring three times a week for 14 weeks. Forty non-Alzheimer's disease women aged 50 to 70 years (60.7 ± 4.1 years) with a mean height of 1.6 ± 0.1 m, mean weight of 73.12 ± 9.0 kg and a mean body mass index of 29.69 ± 3.5 kg/m2, underwent two physical assessments: pre and post the 14 weeks. DNA methylation assays utilized the EPIC Infinium Methylation BeadChip from Illumina. We observed that 14 weeks of CT led to reductions in systolic (p = 0.001) and diastolic (p = 0.017) blood pressure and improved motor skills post-intervention. Among 25 genes linked to AD, CT induced differentially methylated sites in 12 genes, predominantly showing hypomethylated sites (negative β values). Interestingly, despite hypomethylated sites, some genes exhibited hypermethylated sites (positive β values), such as ABCA7, BDNF, and WWOX. A 14-week CT regimen was adequate to induce differential methylation in 12 CE-related genes in healthy older women, alongside improvements in motor skills and blood pressure. In conclusion, this study suggest that combined training can be a strategy to improve physical fitness in older individuals, especially able to induce methylation alterations in genes sites related to development of AD. It is important to highlight that training should act as protective factor in older adults.

Prevalence, cognitive characteristics, and influencing factors of amnestic mild cognitive impairment among older adults residing in an urban community in Chengdu, China

Objective

Dementia is a significant public health concern, and mild cognitive impairment (MCI) serves as a transitional stage between normal aging and dementia. Among the various types of MCI, amnestic MCI (aMCI) has been identified as having a higher likelihood of progressing to Alzheimer's dimension. However, limited research has been conducted on the prevalence of aMCI in China. Therefore, the objective of this study is to investigate the prevalence of aMCI, examine its cognitive characteristics, and identify associated risk factors.

Methods

In this cross-sectional study, we investigated a sample of 368 older adults aged 60 years and above in the urban communities of Chengdu, China. The participants underwent a battery of neuropsychological assessments, including the Mini-Mental State Examination (MMSE), the Clinical Dementia Rating (CDR), Auditory Verbal Learning Test (AVLT), Wechsler's Logical Memory Task (LMT), Boston Naming Test (BNT) and Trail Making Test Part A (TMT-A). Social information was collected by standard questionnaire. Multiple logistic regression analysis was utilized to screen for the risk and protective factors of aMCI.

Results

The data analysis included 309 subjects with normal cognitive function and 59 with aMCI, resulting in a prevalence of 16.0% for aMCI. The average age of participants was 69.06 ± 7.30 years, with 56.0% being females. After controlling for age, gender and education, the Spearman partial correlation coefficient between various cognitive assessments and aMCI ranged from -0.52 for the long-term delayed recall scores in AVLT to 0.19 for the time-usage scores in TMT-A. The results indicated that all cognitive domains, except for naming scores (after semantic cue of BNT) and error quantity (in TMT-A), showed statistically significant associations with aMCI. Furthermore, the multiple logistic regression analysis revealed that older age (OR = 1.044, 95%CI: 1.002~1.087), lower educational level, and diabetes (OR = 2.450, 95%CI: 1.246~4.818) were risk factors of aMCI.

Conclusion

This study found a high prevalence of aMCI among older adults in Chengdu, China. Individuals with aMCI exhibited lower cognitive function in memory, language, and executive domains, with long-term delayed recall showing the strongest association. Clinicians should prioritize individuals with verbal learning and memory difficulties, especially long-term delayed recall, in clinical practice.

Converged avenues: depression and Alzheimer's disease- shared pathophysiology and novel therapeutics

Depression, a highly prevalent disorder affecting over 280 million people worldwide, is comorbid with many neurological disorders, particularly Alzheimer's disease (AD). Depression and AD share overlapping pathophysiology, and the search for accountable biological substrates made it an essential and intriguing field of research. The paper outlines the neurobiological pathways coinciding with depression and AD, including neurotrophin signalling, the hypothalamic-pituitary-adrenal axis (HPA), cellular apoptosis, neuroinflammation, and other aetiological factors. Understanding overlapping pathways is crucial in identifying common pathophysiological substrates that can be targeted for effective management of disease state. Antidepressants, particularly monoaminergic drugs (first-line therapy), are shown to have modest or no clinical benefits. Regardless of the ineffectiveness of conventional antidepressants, these drugs remain the mainstay for treating depressive symptoms in AD. To overcome the ineffectiveness of traditional pharmacological agents in treating comorbid conditions, a novel therapeutic class has been discussed in the paper. This includes neurotransmitter modulators, glutamatergic system modulators, mitochondrial modulators, antioxidant agents, HPA axis targeted therapy, inflammatory system targeted therapy, neurogenesis targeted therapy, repurposed anti-diabetic agents, and others. The primary clinical challenge is the development of therapeutic agents and the effective diagnosis of the comorbid condition for which no specific diagnosable scale is present. Hence, introducing Artificial Intelligence (AI) into the healthcare system is revolutionary. AI implemented with interdisciplinary strategies (neuroimaging, EEG, molecular biomarkers) bound to have accurate clinical interpretation of symptoms. Moreover, AI has the potential to forecast neurodegenerative and psychiatric illness much in advance before visible/observable clinical symptoms get precipitated.

An Interaction between Brain-Derived Neurotrophic Factor and Stress-Related Glucocorticoids in the Pathophysiology of Alzheimer's Disease

Both the brain-derived neurotrophic factor (BDNF) and glucocorticoids (GCs) play multiple roles in various aspects of neurons, including cell survival and synaptic function. BDNF and its receptor TrkB are extensively expressed in neurons of the central nervous system (CNS), and the contribution of the BDNF/TrkB system to neuronal function is evident; thus, its downregulation has been considered to be involved in the pathogenesis of Alzheimer's disease (AD). GCs, stress-related molecules, and glucocorticoid receptors (GRs) are also considered to be associated with AD in addition to mental disorders such as depression. Importantly, a growing body of evidence suggests a close relationship between BDNF/TrkB-mediated signaling and the GCs/GR system in the CNS. Here, we introduce the current studies on the interaction between the neurotrophic system and stress in CNS neurons and discuss their involvement in the pathophysiology of AD.

Bridging Reduced Grip Strength and Altered Executive Function: Specific Brain White Matter Structural Changes in Patients with Alzheimer's Disease

Objective

To investigate the correlation between specific fiber tracts and grip strength and cognitive function in patients with Alzheimer's disease (AD) by fixel-based analysis (FBA).

Methods

AD patients were divided into AD with low grip strength (AD-LGS, n=29) and AD without low grip strength (AD-nLGS, n=25), along with 31 normal controls (NC). General data, neuropsychological tests, grip strength and cranial magnetic resonance imaging (MRI) scans were collected. FBA evaluated white matter (WM) fiber metrics, including fiber density (FD), fiber cross-sectional (FC), and fiber density and cross-sectional area (FDC). The mean fiber indicators of the fiber tracts of interest (TOI) were extracted in cerebral region of significant statistical differences in FBA to further compare the differences between groups and analyze the correlation between fiber properties and neuropsychological test scores.

Results

Compared to AD-nLGS group, AD-LGS group showed significant reductions in FDC in several cerebral regions. In AD patients, FDC values of bilateral uncinate fasciculus and left superior longitudinal fasciculus were positively correlated with Clock Drawing Test scores, while FDC of splenium of corpus callosum, bilateral anterior cingulate tracts, forceps major, and bilateral inferior longitudinal fasciculus were positively correlated with the Executive Factor Score of Memory and Executive Screening scale scores.

Conclusion

Reduced grip strength in AD patients is associated with extensive impairment of WM structural integrity. Changes in FDC of specific WM fiber tracts related to executive function play a significant mediating role in the reduction of grip strength in AD patients.

Response to experimental cold-induced pain discloses a resistant category among endurance athletes, with a distinct profile of pain-related behavior and GABAergic EEG markers: a case-control preliminary study

Pain is a major public health problem worldwide, with a high rate of treatment failure. Among promising non-pharmacological therapies, physical exercise is an attractive, cheap, accessible and innocuous method; beyond other health benefits. However, its highly variable therapeutic effect and incompletely understood underlying mechanisms (plausibly involving the GABAergic neurotransmission) require further research. This case-control study aimed to investigate the impact of long-lasting intensive endurance sport practice (≥7 h/week for the last 6 months at the time of the experiment) on the response to experimental cold-induced pain (as a suitable chronic pain model), assuming that highly trained individual would better resist to pain, develop advantageous pain-copying strategies and enhance their GABAergic signaling. For this purpose, clinical pain-related data, response to a cold-pressor test and high-density EEG high (Hβ) and low beta (Lβ) oscillations were documented. Among 27 athletes and 27 age-adjusted non-trained controls (right-handed males), a category of highly pain-resistant participants (mostly athletes, 48.1%) was identified, displaying lower fear of pain, compared to non-resistant non-athletes. Furthermore, they tolerated longer cold-water immersion and perceived lower maximal sensory pain. However, while having similar Hβ and Lβ powers at baseline, they exhibited a reduction between cold and pain perceptions and between pain threshold and tolerance (respectively -60% and - 6.6%; -179.5% and - 5.9%; normalized differences), in contrast to the increase noticed in non-resistant non-athletes (+21% and + 14%; +23.3% and + 13.6% respectively). Our results suggest a beneficial effect of long-lasting physical exercise on resistance to pain and pain-related behaviors, and a modification in brain GABAergic signaling. In light of the current knowledge, we propose that the GABAergic neurotransmission could display multifaceted changes to be differently interpreted, depending on the training profile and on the homeostatic setting (e.g., in pain-free versus chronic pain conditions). Despite limitations related to the sample size and to absence of direct observations under acute physical exercise, this precursory study brings into light the unique profile of resistant individuals (probably favored by training) allowing highly informative observation on physical exercise-induced analgesia and paving the way for future clinical translation. Further characterizing pain-resistant individuals would open avenues for a targeted and physiologically informed pain management.

Association between obesity, physical activity, and cognitive decline in Chinese middle and old-aged adults: a mediation analysis

BACKGROUND AND OBJECTIVES

Epidemiological evidence on obesity and cognitive decline in middle and old-aged individuals is controversial and the effect of physical activity in this chain is sparse and limited. This study aimed to characterize the association between obesity and cognitive decline and the mediating role of physical activity.

METHODS

Data from China Health and Retirement Longitudinal Study (CHARLS) were used, including 7,392 participants aged ≥ 45 years between 2011 and 2018. Cognitive function was assessed via episodic memory and mental status. The total score of cognitive function was the sum of the above two dimensions (0-31 points). The Group-based trajectory modeling (GBTM) was applied to identify the potential heterogeneity of longitudinal changes in cognitive function. Multivariable ordinal logistic regression was used to investigate associations between obesity and cognitive trajectories, taking body mass index (BMI) as the indicator of obesity. Mediation analysis was performed to examine the potential causal chain in which physical activity mediates the relationship between BMI and cognitive decline.

RESULTS

Of the 7,392 analyzed patients (mean [SD] age, 58.0 [8.5] years; 3,916 [53%] male), the median (interquartile range [IQR]) of BMI was 23.4 (21.1-26.0). Four trajectories were identified by the GBTM model, including the high stable (14.9%), the middle stable (46.0%), the middle decline (29.9%), and the low decline groups (9.2%). After controlling potential confounders, obesity was associated with the low decline groups compared with normal weight (adjusted OR 0.81; 95% CI, 0.70-0.94). Mediation analyses showed that only vigorous physical activity significantly explained 5.94% (95% CI, 0.29-11.60%) of the relationship between obesity and cognitive decline. Sensitivity analyses in different subgroups showed comparable results.

CONCLUSION

This study suggests that vigorous physical activity mediates less than 10% of the association between obesity and cognitive decline in middle and old-aged adults. Further studies are warranted to explore the potential factors related to the obesity paradox in the cognitive field.

Adapted Home-Based Exercises in Dementia: An Exploratory Pre-post Pilot and Feasibility Study

The goals of this exploratory pre-post pilot and feasibility study (NCT04916964) were to assess the feasibility and effectiveness of an adapted Test-and-Exercise home-based exercise program on basic functional mobility and executive functions in persons with prodromal or mild Alzheimer's disease. Participants followed an 8 week exercise program at home, once per week with a physiotherapist and twice per week with their usual caregiver or independently. Functional mobility and executive functions were assessed before and after the intervention. Feasibility criteria were recruitment opportunity, participation agreement rate, cost adequacy, and drop-out rate. Twelve participants aged 80.83 ± 4.65 years took part in the study. All the basic functional mobility measures showed small effect sizes. Concerning executive functions, 5 measures showed small to moderate effect sizes. The 4 feasibility criteria were met. A larger scale study would, however, need adaptations and prior research on the ability of this population to use touch-screen technology.

Sex Differences in the Association Between LDL/HDL with Cognitive Decline in Older Adults: National Health and Nutrition Examination Survey

Background

Lipids have a significant impact on the development and functioning of the nervous system, but the sex differences between the association of LDL/HDL, which reflects lipid metabolic status, and cognitive impairment remains unclear.

Objective

We aimed to determine if there were sex differences between the association of LDL/HDL and cognitive function in US older adults.

Methods

This population-based cross-sectional study used data from the National Health and Nutrition Examination Survey (NHANES) 2011-2012 and 2013-2014 cycles. The main outcome was poor cognitive performance defined by the Digit Symbol Substitution Test (DSST) <  34 based on published literature.

Results

A total of 1,225 participants were included in the study, with a cognitive impairment incidence of 25.6% (314/1,225). Multivariate regression models demonstrated a significant association between cognitive decline and each 1-unit increase in LDL/HDL, after adjusting for all covariates (adjusted odds ratio [OR] = 1.36, 95% confidence interval [CI]: 1.11-1.67). Furthermore, subgroup analysis revealed an interaction between LDL/HDL and cognitive impairment in sex subgroups.

Conclusions

LDL/HDL was associated with cognitive impairment in the US older adult population in adjusted models, although the significance of this association was not observed in females.

Effects of 6-Month Combined Physical Exercise and Cognitive Training on Neuropsychological and Neurophysiological Function in Older Adults with Subjective Cognitive Decline: A Randomized Controlled Trial

Background

Multidomain intervention may delay or ameliorate cognitive decline in older adults at risk of Alzheimer's disease, particularly in the memory and inhibitory functions. However, no study systematically investigates the changes of brain function in cognitively-normal elderly with subjective cognitive decline (SCD) when they receive multidomain intervention.

Objective

We aimed to examine whether a multidomain intervention could improve neuropsychological function and neurophysiological activities related to memory and inhibitory function in SCD subjects.

Methods

Eight clusters with a total of 50 community-dwelling SCD older adults were single-blind, randomized into intervention group, which received physical and cognitive training, or control group, which received treatment as usual. For the neuropsychological function, a composite Z score from six cognitive tests was calculated and compared between two groups. For the neurophysiological activities, event-related potentials (ERPs) of memory function, including mismatch negativity (MMN) and memory-P3, as well as ERPs of inhibitory function, including sensory gating (SG) and inhibition-P3, were measured. Assessments were performed at baseline (T1), end of the intervention (T2), and 6 months after T2 (T3).

Results

For the neuropsychological function, the effect was not observed after the intervention. For the neurophysiological activities, improved MMN responses of ΔT2-T1 were observed in the intervention group versus the control group. The multidomain intervention produced a sustained effect on memory-P3 latencies of ΔT3-T1. However, there were no significant differences in changes of SG and inhibition-P3 between intervention and control groups.

Conclusions

While not impactful on neuropsychological function, multidomain intervention enhances specific neurophysiological activities associated with memory function.

Exploring the Nexus between Moderate-to-Vigorous Physical Activity, Self-Disclosure, Social Anxiety, and Adolescent Social Avoidance: Insights from a Cross-Sectional Study in Central China

Objectives: Psychological issues among adolescents represent a prevalent challenge in today's society. The purpose of this study is to explore the associations among moderate-to-vigorous physical activity, self-disclosure, social anxiety, and social avoidance in adolescents. Methods: This study collected cross-sectional data from 427 students in eight provincial key junior and senior high schools in the central China region of three provinces using snowball sampling and convenience sampling from July to August 2023. A structural equation model was employed to investigate the relationship between moderate-to-vigorous physical activity and social avoidance among adolescents. Results: The findings indicate that moderate-to-vigorous physical activity is negatively correlated with social anxiety (standardized coefficient = -0.219, p < 0.001) and positively correlated with self-disclosure (standardized coefficient = 0.454, p < 0.001). Social anxiety is negatively correlated with self-disclosure (standardized coefficient = -0.220, p < 0.001). Social avoidance is positively correlated with social anxiety (standardized coefficient = 0.461, p < 0.001) and negatively correlated with self-disclosure (standardized coefficient = -0.331, p < 0.001). Conclusions: The chain-mediated dual-path model between moderate-to-vigorous physical activity and social avoidance is facilitated by social anxiety and self-disclosure. In other words, adolescents who engage in more moderate to high-intensity physical activities exhibit lower levels of social anxiety, and those who have a stronger inclination for self-disclosure tend to demonstrate lower levels of social avoidance. In light of these findings, it is recommended that the government, society, schools, and families collaborate synergistically to promote the holistic well-being of adolescents and advance the development of a healthier China.

Association between the Number of Days/Week of Different Levels of Physical Activity and Chronic Pain in People of Different Races: A Mendelian Randomization Study

OBJECTIVE

Regular physical activity is beneficial for health, but the effect of the number of days/week of physical activity on chronic pain (CP) remains unclear, so we used a two-sample Mendelian randomization (MR) analysis to explore the relationship between the number of days/weeks of different levels of physical activity and chronic pain in people of different races.

METHODS

We obtained summary data from genome-wide association studies (GWASs) on the number of days/week of physical activity and multisite chronic pain in European, South Asian, East Asian, Middle Eastern, and African American populations. The single-nucleotide polymorphisms (SNPs) of the exposed data were visualized with a Manhattan plot via the R program. MR analysis was performed by the MR-Base platform.

RESULTS

The results indicated that a higher number of days/week with ≥10 min of walking protects against CP in African American and Afro-Caribbean populations (inverse-variance weighting, IVW p < 0.05) but has little effect on people of different races (IVW p > 0.05). A higher number of days/week with ≥10 min of moderate physical activity increased the risk of CP in European and South Asia (IVW p < 0.05) but had little effect on people of different races (IVW p > 0.05). The number of days/week of ≥10 min of vigorous physical activity increased the risk of CP in Europeans (IVW p < 0.05) and protected against CP in African Americans and Afro-Caribbeans (IVW p < 0.05).

CONCLUSIONS

A higher number of days/week of moderate and vigorous physical activity increased the risk of CP in Europeans; however, a higher number of days/week of walking and vigorous physical activity may protect against CP in African American and Afro-Caribbean individuals.

Exploring Successful Cognitive Aging: Insights Regarding Brain Structure, Function, and Demographics

In the realm of cognitive science, the phenomenon of "successful cognitive aging" stands as a hallmark of individuals who exhibit cognitive abilities surpassing those of their age-matched counterparts. However, it is paramount to underscore a significant gap in the current research, which is marked by a paucity of comprehensive inquiries that deploy substantial sample sizes to methodically investigate the cerebral biomarkers and contributory elements underpinning this cognitive success. It is within this context that our present study emerges, harnessing data derived from the UK Biobank. In this study, a highly selective cohort of 1060 individuals aged 65 and above was meticulously curated from a larger pool of 17,072 subjects. The selection process was guided by their striking cognitive resilience, ascertained via rigorous evaluation encompassing both generic and specific cognitive assessments, compared to their peers within the same age stratum. Notably, the cognitive abilities of the chosen participants closely aligned with the cognitive acumen commonly observed in middle-aged individuals. Our study leveraged a comprehensive array of neuroimaging-derived metrics, obtained from three Tesla MRI scans (T1-weighted images, dMRI, and resting-state fMRI). The metrics included image-derived phenotypes (IDPs) that addressed grey matter morphology, the strength of brain network connectivity, and the microstructural attributes of white matter. Statistical analyses were performed employing ANOVA, Mann-Whitney U tests, and chi-square tests to evaluate the distinctive aspects of IDPs pertinent to the domain of successful cognitive aging. Furthermore, these analyses aimed to elucidate lifestyle practices that potentially underpin the maintenance of cognitive acumen throughout the aging process. Our findings unveiled a robust and compelling association between heightened cognitive aptitude and the integrity of white matter structures within the brain. Furthermore, individuals who exhibited successful cognitive aging demonstrated markedly enhanced activity in the cerebral regions responsible for auditory perception, voluntary motor control, memory retention, and emotional regulation. These advantageous cognitive attributes were mirrored in the health-related lifestyle choices of the surveyed cohort, characterized by elevated educational attainment, a lower incidence of smoking, and a penchant for moderate alcohol consumption. Moreover, they displayed superior grip strength and enhanced walking speeds. Collectively, these findings furnish valuable insights into the multifaceted determinants of successful cognitive aging, encompassing both neurobiological constituents and lifestyle practices. Such comprehensive comprehension significantly contributes to the broader discourse on aging, thereby establishing a solid foundation for the formulation of targeted interventions aimed at fostering cognitive well-being among aging populations.

Factors Affecting Physical Activity in People with Dementia: A Systematic Review and Narrative Synthesis

Physical activity (PA) has positive effects on the physical and cognitive functioning of people with dementia. Knowledge about what limits and stimulates people with dementia to participate in PA is essential to promote effective PA implementation and enhance PA levels. Previous reviews primarily included opinion-based studies, using data from interviews, focus groups or dyads. By including implementation studies, we aimed to elaborate on previous reviews by identifying new barriers to PA and new facilitators and motivators for PA. We conducted systematic searches in Pubmed, PsychInfo and Web of Science for studies published up to the 21st of September 2021. Search terms were related to the population of people with dementia, PA interventions and implementation outcomes. Studies were included if PA participation was investigated during actual PA implementation. No restrictions were made regarding study design, date of publication, PA type or outcome measures. Studies not implementing PA or not evaluating the implementation were excluded. Based on 13 empirical studies, we identified 35 barriers, 19 facilitators and 12 motivators. Of these, 21 barriers, 11 facilitators and 4 motivators were not identified by previous reviews. New factors are related to the support for people with dementia from informal and formal caregivers, e.g., revealing the importance of a trusting relationship. Furthermore, support for staff from the institution or an external party is needed to overcome doubts about PA, for example, related to safety and effects. New factors also suggested specific recommendations for the content and organization of the PA intervention, for instance, related to how to give instructions. Overall, factors affecting PA identified with opinion-based or implementation studies are complementary. Our extended overview shows the complexity of PA implementation and may help to personalize PA, develop implementation strategies, facilitate actual PA implementation and free up resources needed for effective implementation.

The relationship between cognitive reserve focused on leisure experiences and cognitive functions in bipolar patients

Bipolar disorder (BP) is characterized by cognitive decline. Individual differences exist in maintaining cognitive function due to daily physical activity and sleep. We examined the relationship between leisure experiences as proxies for cognitive reserve (CR) and cognitive function in patients with bipolar disorder after adjusting for daily physical activity and sleep. The CR of patients with BP (n = 24) and healthy study controls (HC) (n = 24) was assessed using premorbid IQ, years of education, and leisure activity history. Performance-based neuropsychological tests were performed to evaluate cognitive function. A self-reported scale was used to assess resilience. Physical activity and sleep were measured using an activity meter. Verbal fluency, story memory, and verbal memory were significantly positively correlated with the kinds of leisure experiences in patients with BP. A hierarchical regression analysis accounting for confounding factors showed that verbal fluency and memory were associated with the kinds of leisure experiences. Neither years of education nor resilience were significantly associated with neuropsychological scores. Various leisure experiences in patients with BP are associated with higher language-related cognitive functioning. Engaging in various leisure experiences may affect higher cognitive functions related to language.

Association between physical activity measured by accelerometry and cognitive function in older adults: a systematic review

OBJECTIVE

To analyze studies that investigated the association between physical activity assessed by accelerometry and cognitive function in older people.

METHODS

A systematic review was carried out in four electronic databases (PubMed, Web of Science, Scopus, and SportsDiscus).

RESULTS

In total, 195 records were identified. Fifty-two studies were selected for a full evaluation; 23 were selected according to the inclusion criteria adopted and divided into four chapters (characteristics of the studies, the association between physical activity level and cognitive function decline, effects of physical activity in reducing the chances of cognitive function decline and effects of physical activity on brain plasticity. The cross-sectional studies had an average score of 7 points, and the cohort studies obtained 10 points, indicating the high quality of the selected studies. Seven studies indicated an association between Moderate to vigorous physical activities (MVPA) and cognitive function, two specifically indicated a reduction in the chances of cognitive function decline according to the interquartile of MVPA, and three studies indicated improvements in MVPA in brain plasticity.

CONCLUSION

Measured by accelerometry, seems to be favorably associated with important outcomes in cognitive function assessed through questionnaires, imaging analyses, and biochemical markers with older adults.

Relationship between sarcopenic obesity and cognitive function in patients with mild to moderate Alzheimer's disease

BACKGROUND

Previous research has linked sarcopenic obesity (SO) to cognitive function; however, the relationship between cognitive performance and SO Alzheimer's disease (AD) patients remains unclear. This study aimed to investigate their relationship in AD patients.

METHODS

One hundred and twenty mild to moderate AD patients and 56 normal controls were recruited. According to sarcopenia or obesity status, AD patients were classified into subgroups: normal, obesity, sarcopenia, and SO. Body composition, demographics, and sarcopenia parameters were assessed. Cognitive performance was evaluated using neuropsychological scales.

RESULTS

Among the 176 participants, the prevalence of SO in the moderate AD group was higher than in the normal control group. The moderate AD group had the lowest appendicular skeletal muscle mass index (ASMI) and the highest percentage of body fat (PBF). Hypertension and diabetes were more prevalent in the SO group than in the normal group among the subgroups. The sarcopenia and SO groups exhibited worse global cognitive function compared to the normal and obesity groups. Partial correlation analysis revealed that ASMI, PBF, and visceral fat area were associated with multiple cognitive domains scores. In logistic regression analysis, after adjusting for confounders, obesity was not found to be associated with AD. However, sarcopenia (odds ratio (OR) = 5.35, 95% CI: 1.27-22.46) and SO (OR = 5.84, 95% CI: 1.26-27.11) were identified as independent risk factors for AD.

CONCLUSIONS

SO was associated with cognitive dysfunction in AD patients. Moreover, the impact of SO on cognitive decline was greater than that of sarcopenia. Early identification and intervention for SO may have a positive effect on the occurrence and progression of AD.

Physical activity and exercise for the prevention and management of mild cognitive impairment and dementia: a collaborative international guideline

BACKGROUND

Physical activity and exercise have been suggested as effective interventions for the prevention and management of mild cognitive impairment (MCI) and dementia, but there are no international guidelines.

OBJECTIVES

To create a set of evidence- and expert consensus-based prevention and management recommendations regarding physical activity (any bodily movement produced by skeletal muscles that results in energy expenditure) and exercise (a subset of physical activity that is planned, structured, repetitive), applicable to a range of individuals from healthy older adults to those with MCI/dementia.

METHODS

Guideline content was developed with input from several scientific and lay representatives' societies. A systematic search across multidisciplinary databases was carried out until October 2021. Recommendations for prevention and management were developed according to the GRADE and complemented by consensus statements from the expert panels.

RECOMMENDATIONS

Physical activity may be considered for the primary prevention of dementia. In people with MCI there is continued uncertainty about the role of physical activity in slowing the conversion to dementia. Mind-body interventions have the greatest supporting evidence. In people with moderate dementia, exercise may be used for maintaining disability and cognition. All these recommendations were based on a very low/low certainty of evidence.

CONCLUSIONS

Although the scientific evidence on the beneficial role of physical activity and exercise in preserving cognitive functions in subjects with normal cognition, MCI or dementia is inconclusive, this panel, composed of scientific societies and other stakeholders, recommends their implementation based on their beneficial effects on almost all facets of health.