Physical Activity for Executive Function and Activities of Daily Living in AD Patients: A Systematic Review and Meta-Analysis

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.

Effectiveness of physical activity interventions for core symptoms of autism spectrum disorder: A systematic review and meta-analysis

In this paper, systematic review and meta-analysis were used to demonstrate the effectiveness of physical activity intervention on core symptoms of autism spectrum disorder (ASD). Physical activity intervention for core symptoms of ASD were retrieved by computer from the PubMed Cochrane Library, Web of Science, APA PsycNet, and CNKI database during December 1, 2022. Two researchers evaluated the quality of the included literature and extracted the data. Sixteen studies were eventually included, with a total of 587 patients with ASD. Meta-analysis showed that the core symptoms of ASD patients decreased after physical activity intervention, ES(g) = 0.681(95% CI: 0.380-0.982, p = 0.000), specifically, physical activity improved the reduction of social disorder ES(g) = 0.749(95% CI: 0.524-0.973) and repeated rigid behavior ES(g) = 0.553 (95% CI: -0.079 to 1.186). Subgroup analysis showed that preschool children with ASD who were 3-6 years old, exercised for more than 12 weeks, more than 3 times a week, and exercised for more than 90 min per session had better improvement in core symptoms after participating in physical activity. The conclusion of this paper is that physical activity intervention can improve the core symptoms of ASD, especially the reduction of social disorders and repetitive behaviors.

Effect of Music Interventions on Cognitive Function in Older Adults With Mild Cognitive Impairment: A Systematic Review

The purpose of the current systematic review was to examine the effects of music interventions on cognitive function in older adults with mild cognitive impairment (MCI). A systematic search of CINAHL, PubMed, PsycINFO, and Web of Science databases was performed. Studies examining the effects of music interventions on cognitive function in older adults with MCI were included. Narrative synthesis for cognitive outcomes postintervention was performed. A total of 11 articles met inclusion criteria. Music interventions significantly improved global cognitive function, verbal fluency, executive function, and spatial function in older adults with MCI. Included studies were heterogeneous in terms of the type of intervention, cognitive assessment tool, and intervention duration. Six studies were at risk of bias due to missing data and confounding factors. Our findings suggest that music interventions can be an effective strategy to improve cognitive function for older adults with MCI. However, findings should be interpreted with caution. More rigorous studies with various types of music interventions investigating cognitive domain-specific effects are needed. [Research in Gerontological Nursing, 16(5), 259-268.].

Does Multicomponent Physical Exercise Training Work for Dementia? Exploring the Effects on Cognition, Neuropsychiatric Symptoms, and Quality of Life

OBJECTIVE

To explore the effects of a multicomponent training (MT) physical exercise intervention in the cognitive function, neuropsychiatric symptoms, and quality of life of older adults with major neurocognitive disorder (NCD).

METHODS

Quasi-experimental controlled trial. Thirty-six individuals (25 female) were equally distributed to an exercise group (aged 74.33 ± 5.87 years) or a control group (aged 81.83 ± 6.18 years). The Alzheimer's Disease Assessment Scale - Cognitive (ADAS-Cog), the Neuropsychiatric Inventory (NPI) and the Quality of Life - Alzheimer's Disease (QoL-AD) tests were performed before and after the intervention.

RESULTS

There was no clear interaction effect factor of intervention on ADAS-Cog (B = 1.33, 95% CI: -2.61 - 5.28, P = .513), NPI (B = -8.35, 95% CI: -18.48 - 1.72, P = .115), and QoL-AD (B = 2.87, 95% CI: .01 - 5.73, P = .058).

CONCLUSIONS

The 6-month MT physical exercise intervention did not present evidence of slowing down cognitive decline neither improving neuropsychiatric symptomatology, and quality of life of older adults with major NCD. Future studies with larger samples are needed to better understand the impact of physical exercise interventions using MT methodology on specific cognitive abilities, neuropsychiatric symptoms, and quality of life domains.

Effects of Exercise on Quality of Life in Subjects with Alzheimer's Disease: Systematic Review with Meta-Analysis of Randomized Clinical Trials

Alzheimer's disease is a type of dementia that progressively affects memory, thinking, and behavior. It can interfere with daily activities and lead to a decline in cognitive abilities over time. Exercise-based interventions can complement Alzheimer's disease treatment. Exercise is a valuable tool in all healthcare settings and has shown promise as an effective cognitive improvement intervention for people with cognitive impairments. This systematic review and meta-analysis aimed to analyze the effect of physical exercise on the QoL of subjects with Alzheimer's disease. A search was performed with the help of the electronic databases PubMed and Web of Science. Randomized controlled trials with exercise-based interventions were selected. Four studies met the inclusion criteria, which included interventions based on exercise. The effects were summarized using standardized mean differences (95% confidence intervals) using random-effect models. The results showed that exercise had no significant effect on the QoL of subjects with Alzheimer. Thus, the effect of exercise interventions on the QoL of patients with Alzheimer's disease is not conclusive. More research is needed about this topic and the way in which the QoL is assessed; the necessity to conduct an objective way to assess the QoL in this population is mandatory.

Effects of physical activity interventions on executive function in older adults with dementia: A meta-analysis of randomized controlled trials

BACKGROUND

To date quantitative meta-analysis with large samples to investigate the effects and potential moderators of physical activity (PA) on executive function (EF) in older adults with dementia is insufficient. Therefore, we conducted this meta-analysis.

DESIGN

Meta-analysis of randomized controlled trials (RCTs).

PARTICIPANTS

Old people with Alzheimer's disease (AD) or related dementia of varying types and severity as the primary diagnosis.

METHODS

PubMed, Web of Science, the Cochrane Library and Embase databases were searched for relevant studies published from 01 January, 2010 to 01 March, 2022. The results of executive function were reported in all RCTs. Random-effects meta-analysis was used to calculate the size of effects. Subgroup analyses of three moderators (including the specific sub-domains of EF, exercise prescription variables, and sample characteristics) were performed.

RESULTS

Eighteen RCTs were included with a combined sample size of 1366. Overall, PA interventions improved overall EF (standardized mean difference [SMD]=0.23, 95% confidence interval [CI] 0.05 to 0.41, p<0.05). The EF sub-domain "planning" was significant moderator (SMD=0.31, 95%CI 0.11 to 1.51, p<0.01), but inhibitory control, working memory and cognitive flexibility were not significant. Regarding exercise prescription variables, type of resistance training; moderate intensity; total duration ≤24 weeks and short (once or twice a week) frequency improved overall EF performance. Session length may be a moderator. Regarding sample characteristics, old-old, AD and both dementia and AD had significant benefits.

CONCLUSIONS AND IMPLICATIONS

EF in older adults with AD or related dementia benefited from physical activity, and the benefit was affected by the type, intensity, total duration, frequency of exercise. Physical activity can be an alternative intervention in aging patients with dementia, to improve EF performance or prevent or EF decline.

Impact of dysexecutive syndrome in quality of life in Alzheimer disease: What we know now and where we are headed

Alzheimer's disease (AD) is a common form of dementia that leads to multiple repercussions in the patient's life. This condition's clinical characteristics include loss of memory, temporal and spatial disorientation, language or executive dysfunction, and subsequent decline of social function. Dysexecutive syndrome (DS), the second most frequent neuropsychological dysfunction in AD, affects multiple brain areas and causes cognitive, behavioral, and emotional difficulties. We aimed to analyze the association between DS and AD and elucidate possible lack of evidence that may urge further research on this theme. Especially when dealing with such a disabling disease, where new findings can directly imply a better prognosis.

Developmental links between executive function and emotion regulation in early toddlerhood

Developmental associations between poor executive function (EF) and problem behaviors in toddlerhood indicate that the interplay between cognition and affect begins very early in life (Hughes, Devine, Mesman, & Blair, 2020). However, very few longitudinal studies of toddlers have included direct measures of both EF and emotion regulation (ER). In addition, while models of ER highlight the importance of situational contexts (e.g., Miller, McDonough, Rosenblum, Sameroff, 2005), existing work is limited by a heavy reliance on lab-based observations of mother-child dyads. Addressing these twin gaps, the current study of 197 families included video-based ratings of ER in toddlers' dyadic play with both mothers and fathers at each of two time-points (14- and 24-months), with parallel measures of EF being gathered in each home visit. Our cross-lagged analyses showed that EF at 14 months predicted ER at 24 months, but this association was limited to observations of toddlers with mothers. It was also asymmetric: ER at 14 months did not predict EF at 24 months. These findings support co-regulation models of early ER and highlight the predictive utility of very early individual differences in EF.

Effects of preventive interventions on neuroimaging biomarkers in subjects at-risk to develop Alzheimer's disease: A systematic review

Alzheimer's Disease (AD) is a multifactorial and complex neurodegenerative disorder. Some modifiable risk factors have been associated with an increased risk of appearance of the disease and/or cognitive decline. Preventive clinical trials aiming at reducing one or combined risk factors have been implemented and their potential effects assessed on cognitive trajectories and on AD biomarkers. However, the effect of interventions on surrogate markers, in particular imaging biomarkers, remains poorly understood. We conducted a review of the literature and analyzed 43 interventional studies that included physical exercise, nutrition, cognitive training or multidomain interventions, and assessed various brain imaging biomarkers, to determine the effects of preventive interventions on imaging biomarkers for subjects at-risk to develop AD. Deciphering the global and regional brain effect of each and combined interventions will help to better understand the interplay relationship between multimodal interventions, cognition, surrogate brain markers, and to better design primary and secondary outcomes for future preventive clinical trials. Those studies were pondered using generally-admitted quality criteria to reveal that interventions may affect the brain of patients with cognitive impairment rather than those without cognitive impairment thus indicating that particular care should be taken when selecting individuals for interventions. Additionally, a majority of the studies concurred on the effect of the interventions and particularly onto the frontal brain areas.

The interrelationship between physical activity intensity, cardiorespiratory fitness, and executive function in middle-aged adults: An observational study of office workers

Background

Previous evidence supports a beneficial effect of physical activity on executive function across the whole lifespan. Yet, the interrelationships of the intensities of physical activity, cardiorespiratory fitness, and executive function require further investigation in adults.

Aim

Using unfiltered accelerometry data and high-resolution intensity classification, we sought to estimate the associations of physical activity with cardiorespiratory fitness and executive function in adult office workers.

Methods

We included 343 full-time office workers (mean age: 42.41 years, range of age: 36-49 years). Executive function was assessed using Stroop, Trail making tests (part-B), and 2-back tests, and a composite score was produced to reflect the general executive function performance. Physical activity was assessed using the Actigraph GT3X+-monitor, worn by each participant for seven days at the hip. Raw accelerometry data were processed by the 10 Hz frequency extended method and divided into 22 intensity bins and sleep time. Cardiorespiratory fitness was estimated using the submaximal Ekblom-Bak cycle ergometer test. Data were analyzed using partial least squares regressions.

Results

In adults, cardiorespiratory fitness was closely correlated with a wide range of absolute physical activity intensity patterns. A higher level of executive function in adults was associated with both higher absolute physical activity intensities and cardiorespiratory fitness, which was independent of age, sex, and education levels. A very weak association between intensities, fitness, and executive function was observed in high-fit adults. Among low-fit adults, although a positive association started already toward the upper end of moderate intensity, there still appeared to be an association between intensities, cardiorespiratory fitness, and executive function. That is, cardiorespiratory fitness may mediate the association between absolute physical activity intensities and executive function up to a certain level.

Conclusion

The maintenance of executive function in adulthood was related to both physical activity intensities and cardiorespiratory fitness, while their interrelationship was not equal across fitness levels. It is highly recommended to consider the cardiorespiratory fitness level in future studies that focus on executive functions in aging as well when designing individualized physical activity training programs.

Training Willpower: Reducing Costs and Valuing Effort

The integrative model of effortful control presented in a previous article aimed to specify the neurophysiological bases of mental effort. This model assumes that effort reflects three different inter-related aspects of the same adaptive function. First, a mechanism anchored in the salience network that makes decisions about the effort that should be engaged in the current task in view of costs and benefits associated with the achievement of the task goal. Second, a top-down control signal generated by the mechanism of effort that modulates neuronal activity in brain regions involved in the current task to filter pertinent information. Third, a feeling that emerges in awareness during effortful tasks and reflects the costs associated with goal-directed behavior. The aim of the present article is to complete this model by proposing that the capacity to exert effortful control can be improved through training programs. Two main questions relative to this possible strengthening of willpower are addressed in this paper. The first question concerns the existence of empirical evidence that supports gains in effortful control capacity through training. We conducted a review of 63 meta-analyses that shows training programs are effective in improving performance in effortful tasks tapping executive functions and/or self-control with a small to large effect size. Moreover, physical and mindfulness exercises could be two promising training methods that would deserve to be included in training programs aiming to strengthen willpower. The second question concerns the neural mechanisms that could explain these gains in effortful control capacity. Two plausible brain mechanisms are proposed: (1) a decrease in effort costs combined with a greater efficiency of brain regions involved in the task and (2) an increase in the value of effort through operant conditioning in the context of high effort and high reward. The first mechanism supports the hypothesis of a strengthening of the capacity to exert effortful control whereas the second mechanism supports the hypothesis of an increase in the motivation to exert this control. In the last part of the article, we made several recommendations to improve the effectiveness of interventional studies aiming to train this adaptive function."Keep the faculty of effort alive in you by a little gratuitous exercise every day."James (1918, p. 127).

Physical Activity Improves Cognition and Activities of Daily Living in Adults with Alzheimer’s Disease: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objective: The purpose of this meta-analysis was to examine the effects of physical activity (PA) on cognition and activities of daily living in adults with Alzheimer’s Disease (AD). Methods: Six electronic databases (MEDLINE, CINAHL, PsycArticles, SPORTDiscus, EMBASE and CNKI) were used to search for potential studies from inception until October 2021. Randomized controlled trials (RCTs) investigating the effect of physical activity (PA) on cognition and activities of daily living in AD patients compared to a control condition were included. The effect sizes were synthesized using a random effects model with a 95% confidence interval (CI). Results: Sixteen articles including 945 participants (aged 70 to 88 years, 34.6% male) met the inclusion criteria. The pooled effect sizes demonstrated that PA intervention was associated with significant improvements in global cognition (Standard Mean Difference (SMD) = 0.41, 95% CI [0.24, 0.58], p < 0.01) and activities of daily living (SMD = 0.56, 95% CI [0.32, 0.79], p < 0.01) in AD patients. Subgroup analyses suggested that PA for 3–4 times per week for 30–45 min for more than 12 weeks had a relatively strong effect on improving global cognition in AD patients. The sensitivity analysis showed robust results. Conclusions: The findings from the current meta-analysis suggested that AD patients can improve their global cognition and Activities of Daily Living (ADL) through engaging in aerobic and mixed exercise (aerobic and anaerobic exercise).

The Coaching for Cognition in Alzheimer's (COCOA) trial: Study design

Comprehensive treatment of Alzheimer's disease (AD) requires not only pharmacologic treatment but also management of existing medical conditions and lifestyle modifications including diet, cognitive training, and exercise. We present the design and methodology for the Coaching for Cognition in Alzheimer's (COCOA) trial. AD and other dementias result from the interplay of multiple interacting dysfunctional biological systems. Monotherapies have had limited success. More interventional studies are needed to test the effectiveness of multimodal multi‐domain therapies for dementia prevention and treatment. Multimodal therapies use multiple interventions to address multiple systemic causes and potentiators of cognitive decline and functional loss; they can be personalized, as different sets of etiologies and systems responsive to therapy may be present in different individuals. COCOA is designed to test the hypothesis that coached multimodal interventions beneficially alter the trajectory of cognitive decline for individuals on the spectrum of AD and related dementias (ADRD). COCOA is a two‐arm prospective randomized controlled trial (RCT). COCOA collects psychometric, clinical, lifestyle, genomic, proteomic, metabolomic, and microbiome data at multiple timepoints across 2 years for each participant. These data enable systems biology analyses. One arm receives standard of care and generic healthy aging recommendations. The other arm receives standard of care and personalized data‐driven remote coaching. The primary outcome measure is the Memory Performance Index (MPI), a measure of cognition. The MPI is a summary statistic of the MCI Screen (MCIS). Secondary outcome measures include the Functional Assessment Staging Test (FAST), a measure of function. COCOA began enrollment in January 2018. We hypothesize that multimodal interventions will ameliorate cognitive decline and that data‐driven health coaching will increase compliance, assist in personalizing multimodal interventions, and improve outcomes for patients, particularly for those in the early stages of the AD spectrum.

Effect of Physical Exercise on Cognitive Function of Alzheimer's Disease Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trial

This review aims to systematically review the effects of physical exercise on the cognitive performance of patients with Alzheimer's disease (AD) and its mechanisms of action. Databases such as Web of Science, PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials were searched until December 2021. A randomized controlled trial (RCT) to assess the effect of an exercise intervention (compared with no exercise) on patients with AD. The measures included cognitive function [Mini-Mental State Examination (MMSE), Alzheimer's Disease assessment scale-cognitive (ADAS-Cog), Montreal cognitive assessment scale (MoCA) and Executive Function (EF)]. The methodological quality of the included literature was assessed using the Physiotherapy Evidence Database (PEDro) scale. Twenty-two studies (n = 1647, mean age: 77.1 ± 6.3 years) were included in the systematic review, sixteen of which were included in the meta-analysis. A systematic review and meta-analysis revealed that physical exercise positively affects cognitive performance in older patients with AD. However, the positive effects of the intervention should be interpreted with caution considering the differences in methodological quality, type, frequency, and duration of exercise in the included studies. Future studies should consider the design rigor and specification of RCT protocols.

Exercise interventions in Alzheimer's disease: A systematic review and meta-analysis of randomized controlled trials

AIMS

To assess the potential multi-domain benefits of exercise interventions on patients with Alzheimer's disease (AD), as well as to determine the specific effects of different exercise modalities (aerobic, strength, or combined training).

METHODS

A systematic search was conducted in PubMed and Web of Science until March 2021 for randomized controlled trials assessing the effect of exercise interventions (compared with no exercise) on patients with AD. Outcomes included cognitive function (mini-mental state examination [MMSE] test), physical function (e.g., 6-minute walking test [6MWT]), functional independence (Barthel index), and neuropsychiatric symptoms (Neuropsychiatric Inventory [NPI]). A random-effects meta-analysis was conducted.

RESULTS

28 studies (total n = 1337 participants, average age 79-90 years) were included in the systematic review, of which 21 could be meta-analyzed. Although considerable heterogeneity was found, exercise interventions induced several significant benefits, including in Barthel index (n = 147 patients, mean difference [MD]=8.36 points, 95% confidence interval [CI]=0.63-16.09), 6MWT (n = 369, MD=84 m, 95% CI=44-133)), and NPI (n = 263, MD=-4.4 points, 95% CI=-8.42 to -0.38). Benefits were also found in the MMSE test, albeit significance was only reached for aerobic exercise (n = 187, MD=2.31 points, 95% CI 0.45-4.27).

CONCLUSIONS

Exercise interventions appear to exert multi-domain benefits in patients with AD.

Personalized treatment interventions: nonpharmacological and natural treatment strategies in Alzheimer's disease

Introduction: Alzheimer's disease (AD) is a slow, irreversible, progressive, complex, and fatal neurodegenerative disorder. Available pharmacological treatment, known for almost two decades, does not cure the disease, but only alleviates the symptoms, with various efficacy and different side effects. Therefore, there is an unmet need to find other person-centered or personalized approaches to treat AD.Areas covered: This article describes the application of precision medicine-like approaches utilizing nonpharmacological treatment strategies and the use of natural products in personalized care for patients with AD.Expert opinion: Due to the heterogeneity of disease symptoms, somatic conditions, and patient preferences, there is definitely no "one size fits all" intervention. Therefore, individualized treatment choice is based on dementia stage, medical and psychiatric comorbidity, leading symptoms, patient preferences, and remaining capacity of the patient. In the absence of disease-modifying agents, a patient-centered, multidisciplinary team approach appears to be the best option to alleviate the heavy symptomatic burden in this unfortunate population. Hence, appropriate interventions can be offered along the AD continuum, while a better understanding of personal characteristics might help in establishing optimal individualized treatment, as well as its duration and intensity, to deliver interventions in the most effective ways.