The effect of combined cognitive intervention and physical exercise on cognitive function in older adults with mild cognitive impairment: a meta-analysis of randomized controlled trials

Components of effective exergame-based training to improve cognitive functioning in middle-aged to older adults - A systematic review and meta-analysis

BACKGROUND

Exergame-based training is currently considered a more promising training approach than conventional physical and/or cognitive training.

OBJECTIVES

This study aimed to provide quantitative evidence on dose-response relationships of specific exercise and training variables (training components) of exergame-based training on cognitive functioning in middle-aged to older adults (MOA).

METHODS

We conducted a systematic review with meta-analysis including randomized controlled trials comparing the effects of exergame-based training to inactive control interventions on cognitive performance in MOA.

RESULTS

The systematic literature search identified 22,928 records of which 31 studies were included. The effectiveness of exergame-based training was significantly moderated by the following training components: body position for global cognitive functioning, the type of motor-cognitive training, training location, and training administration for complex attention, and exercise intensity for executive functions.

CONCLUSION

The effectiveness of exergame-based training was moderated by several training components that have in common that they enhance the ecological validity of the training (e.g., stepping movements in a standing position). Therefore, it seems paramount that future research focuses on developing innovative novel exergame-based training concepts that incorporate these (and other) training components to enhance their ecological validity and transferability to clinical practice. We provide specific evidence-based recommendations for the application of our research findings in research and practical settings and identified and discussed several areas of interest for future research.

PROSPERO REGISTRATION NUMBER

CRD42023418593; prospectively registered, date of registration: 1 May 2023.

Acute Effect of Simultaneous Exercise and Cognitive Tasks on Cognitive Functions in Elderly Individuals with Mild Cognitive Impairment

The increasing prevalence of age-related cognitive decline, alongside the aging global population, underscores the urgent need for innovative and effective preventative strategies. While the advantages of combining physical and cognitive exercises have been recognized as a promising approach to address these socioeconomic challenges, the acute effects of such interventions on cognitive functions remain understudied. This study aimed to investigate whether simultaneous physical and cognitive exercise has a greater beneficial impact on the cognitive functions of older adults with mild cognitive impairment (MCI) than physical exercise alone or reading activities. A total of 44 MCI patients (75% females aged between 65 and 75 years) were randomly assigned to one of three groups: aerobic exercise alone (EG group, n = 15), aerobic combined with cognitive exercises (CEG group, n = 15), or a reading task for controls (CG group, n = 14). Attention, memory, and problem solving were assessed before and after the acute intervention using the Tower of Hanoi, Digit Span, and Stroop tasks, respectively. Statistical analysis revealed that both of the experimental interventions appeared to enhance cognitive function scores (p < 0.05), except for the number of moves in the Tower of Hanoi task, where no improvement was noted. In contrast, no significant differences in any cognitive performance measures were observed following the reading session. Notably, the CEG group exhibited a more pronounced positive impact, especially on working memory. This advantage was specifically evident in the digit span tasks, where significantly greater percentage gains were found in the CEG than in the CG (p = 0.02), while no significant difference existed between the EG and CG. Simultaneous combined exercise has proven to be a more effective method than aerobic physical exercise alone for improving cognitive function. The results of this study are recommended for inclusion in clinical practice guidelines to maintain the mental health of older adults, as simultaneous exercise seems to offer a time-efficient strategy to enhance cognitive performance in adults with MCI.

Compared to exercise, the effects of exercise combined with cognitive training in people with mild cognitive impairment: a network meta-analysis

OBJECTIVES

The study aimed to evaluate the relative effectiveness of exercise combined with cognitive training (E&CT) in improving cognitive function compared to exercise alone.

METHOD

PubMed, Embase, Cochrane Central Register of Controlled Trials, SPORTDiscus, and OpenGrey were systematically searched. Additional screenings were performed by reviewing citations of relevant articles. Studies were included if they met inclusion criteria. Both pairwise and network meta-analyses were performed using a random effects model in Stata 15.0.

RESULTS

Totally, 46 trials from 54 literature (n = 2846) were eligible for inclusion in the meta-analysis. The network meta-analysis indicated that exercise alone was more efficacious than E&CT in improving global cognition and multicomponent exercise exhibited the highest likelihood (SUCRA value= 89.0%) of being the most effective type. Regarding memory function, E&CT presented greater potential than exercise alone, with the interactive modality ranking first (SUCRA value = 88.4%). Multicomponent exercise was identified as the top intervention for enhancing executive function. The overall quality of the included studies was rated as moderate, and the certainty of evidence ranged from low to high.

CONCLUSION

Multicomponent exercise emerged as the optimal intervention for improving global cognition and executive function. Nevertheless, for memory function, the interactive modality of E&CT demonstrated the highest probability of being the most effective choice.

Effects of computerized cognitive training on biomarker responses in older adults with mild cognitive impairment: A scoping review

Background and Aims

Mild cognitive impairment (MCI) is a widespread condition in older individuals, posing significant risk of dementia. However, limited research has been conducted to explore effective interventions and clarify their impact at the neural level. Therefore, this study aimed to investigate the effects of computerized cognitive training (CCT) and explore the associated neural mechanisms in preventing dementia in older individuals with MCI, with a view to inform future intervention efforts.

Methods

We reviewed the effects of CCT on biomarker outcomes in older adults with MCI. The search was conducted for studies published between 2010 and May 10, 2023, using three search engines: PubMed, Scopus, and Cumulative Index to Nursing and Allied Health Literature. The inclusion criteria were as follows: studies that involved participants diagnosed with MCI, included CCT, included quantitative assessment of biomarker results, and conducted randomized controlled trials.

Results

Sixteen studies that used biomarkers, including magnetic resonance imaging, electroencephalography (EEG), functional near-infrared spectroscopy (fNIRS), and blood or salivary biomarkers, were extracted. The results showed that CCT caused changes in structure and function within the main brain network, including the default mode network, and decreased both theta rhythm activity on EEG and prefrontal activity on fNIRS, with improvement in cognitive function. Furthermore, CCT combined with physical exercise showed more significant structural and functional changes in extensive brain regions compared with CCT alone. Virtual reality-based cognitive training improved not only executive function but also instrumental activities of daily living.

Conclusion

CCT causes functional and structural changes in extensive brain regions and improves cognitive function in older adults with MCI. Our findings highlight the potential of individualized intervention methods and biomarker assessment according to the specific causes of MCI. Future research should aim to optimize these personalized therapeutic strategies to maximize the benefits of CCT in older adults with MCI.

Prediction and mediation analysis for treatment responses to combined cognitive and physical training for older adults

Diminished cognitive and physical functions negatively affect the daily functions of individuals. Although combined cognitive and physical training prevents instrumental activities of daily living (IADL) disability in older adults, no predictive model or mediation analysis of IADL after combined training exists. This study aims to employ prediction and mediation analysis to identify the predictors of IADL performance and to elucidate the mediators of the association between baseline global cognition and subsequent IADL performance following combined cognitive and physical training. This study involved 177 participants aged 60 years and older who underwent combined training. Cognitive function was measured with the Montreal Cognitive Assessment (MoCA), Digit Symbol Substitution Test (DSST), Color Trails Test, Word List, and a dual task; physical function with the Timed Up and Go (TUG) test; daily function with the Lawton IADL Scale. We conducted regression analyses to identify the predictors of IADL performance, and mediation analysis to examine whether DSST and TUG mediate the relationship between MoCA and IADL. The pre-intervention DSST and TUG were significant independent predictors of post-intervention IADL. The association between the pre-intervention MoCA and post-intervention IADL was mediated by pre-intervention DSST and TUG. This study highlighted the importance of measuring and improving processing speed and functional mobility before and during interventions to enhance IADL outcomes.Trial registration: NCT03619577, 23/07/2018; NCT04689776, 29/12/2020.

Lecanemab Questions

The recently published results of the 18-month randomized controlled trial of lecanemab, reporting the efficacy of the drug in slowing the progression of early Alzheimer disease, quickly led to approval by the FDA and widespread acceptance of lecanemab treatment. However, there are a number of matters that deserve further consideration. The success of blinding was not assessed, even as infusion reactions and the cerebral pathology underlying amyloid-related imaging abnormalities could have signaled to many participants that they were on drug, potentially exerting a potent placebo effect. The value of the outcome to participants is not defined in the absolute terms necessary for clinical decision-making, and the difference attributable to lecanemab was between 18% and 46% of estimates of the minimal clinically important difference on the Clinical Dementia Rating Scale Sum of Boxes. The attenuation of change on the Alzheimer's Disease Assessment Scale-Cognitive 14 achieved by lecanemab at 18 months was 50% of that achieved by donepezil at 6 months. Lecanemab treatment imposes a high treatment burden. The fact that the burden commences at the initiation of lecanemab treatment, whereas the benefit accrues years later requires us to take into account value discounting over time, which would significantly reduce the benefit/burden ratio. Finally, treatment with monoclonal antibodies to cerebral amyloid has consistently been associated with progressive cerebral atrophy. At the least, these issues should be raised in treatment discussions with patients. They also suggest a need to very seriously reconsider how we evaluate clinical trial results preparatory to translating them into clinical practice. Some suggestions are provided.

Independent Association between Cognitive Frailty and Cardio-Ankle Vascular Index in Community-Dwelling Older Adults

INTRODUCTION

Although arterial stiffness has been suggested to be associated with poor physical function and mild cognitive impairment (MCI), its association with cognitive frailty (CF), a comorbidity of both, is unclear. This study aims to examine the association between CF and arterial stiffness in community-dwelling older adults.

METHODS

A cross-sectional analysis of 511 community-dwelling older adults aged 65 years or older (mean age 73.6 ± 6.2 years, 63.6% women), who participated in a community cohort study (Tarumizu Study, 2019), was conducted. Poor physical function was defined as either slowness (walking speed <1.0 m/s) or weakness (grip strength <28 kg for men and <18 kg for women). MCI was defined by the National Center for Geriatrics and Gerontology Functional Assessment Tool as a decline of at least 1.5 standard deviation from age- and education-adjusted baseline values in any one of the four cognitive domains (memory, attention, executive, and information processing). CF was defined as the combination of poor physical function and MCI. Arterial stiffness was measured using the Cardio-Ankle Vascular Index (CAVI), and the average of the left and right sides (mean CAVI) was used.

RESULTS

Multinomial logistic regression analysis adjusted for covariates was performed with the four groups of robust, poor physical function, MCI, and CF as dependent variables and mean CAVI as an independent variable. Using the robust group as reference, the poor physical function and MCI groups showed no significant relationship with the mean CAVI. The mean CAVI was significantly higher in the CF group (odds ratio 1.62, 95% confidence interval: 1.14-2.29).

CONCLUSION

A significant association was found between CF and the higher CAVI (progression of arterial stiffness). Careful observation and control of CAVI, which is also an indicator of arterial stiffness, may be a potential target for preventive interventions for CF.

Mid-Term and Long-Lasting Psycho-Cognitive Benefits of Bidomain Training Intervention in Elderly Individuals with Mild Cognitive Impairment

Background: This study investigated whether combining simultaneous physical and cognitive training yields superior cognitive outcomes compared with aerobic training alone in individuals with mild cognitive impairment (MCI) and whether these benefits persist after four weeks of detraining. Methods: Forty-four people with MCI (11 males and 33 females) aged 65 to 75 years were randomly assigned to an 8-week, twice-weekly program of either aerobic training (AT group, n = 15), aerobic training combined with cognitive games (ACT group, n = 15), or simply reading for controls (CG group, n = 14). Selective attention (Stroop), problem-solving (Hanoi Tower), and working memory (Digit Span) tasks were used to assess cognitive performances at baseline, in the 4th (W4) and 8th weeks (W8) of training, and after 4 weeks of rest (W12). Results: Both training interventions induced beneficial effects on all tested cognitive performance at W4 (except for the number of moves in the Hanoi tower task) and W8 (all p <0.001), with the ACT group exhibiting a more pronounced positive impact than the AT group (p < 0.05). This advantage was specifically observed at W8 in tasks such as the Stroop and Tower of Hanoi (% gain ≈40% vs. ≈30% for ACT and AT, respectively) and the digit span test (% gain ≈13% vs. ≈10% for ACT and AT, respectively). These cognitive improvements in both groups, with the greater ones in ACT, persisted even after four weeks of detraining, as evidenced by the absence of a significant difference between W8 and W12 (p > 0.05). Concerning neuropsychological assessments, comparable beneficial effects were recorded following both training regimens (all p < 0.05 from pre- to post-intervention). The control group did not show any significant improvement in most of the cognitive tasks. Conclusions: The greater mid-term and long-lasting effects of combined simultaneous physical-cognitive training underscores its potential as a cost-effective intervention for the prevention and management of cognitive decline. While these results are valuable in guiding optimal physical and mental activity recommendations for adults with MCI, further neurophysiological-based studies are essential to offer robust support and deepen our understanding of the mechanisms underlying these promising findings.

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.

Feasibility, usability, and acceptance of "Brain-IT"-A newly developed exergame-based training concept for the secondary prevention of mild neurocognitive disorder: a pilot randomized controlled trial

Background

Exergames provide a promising new approach to implement simultaneous motor-cognitive training, which may support preventing the decline in cognitive functioning in older adults who have a mild neurocognitive disorder (mNCD).

Objectives

To evaluate feasibility, system usability, and acceptance of "Brain-IT", a newly developed training concept combining exergame-based motor-cognitive training and heart rate variability (HRV) guided resonance breathing for the secondary prevention of mNCD.

Methods

A pilot randomized controlled trial (RCT) with an allocation ratio of 2:1 (i.e., intervention:control) was conducted. The control group proceeded with usual care. The intervention group performed a 12-week training according to the "Brain-IT" training concept implemented with the "Senso Flex" (Dividat AG) exergaming system in addition to usual care. Feasibility and usability outcomes were analyzed using descriptive statistics. User acceptance was analyzed qualitatively and using Friedman analysis of variance (ANOVA), as well as Wilcoxon signed-rank tests.

Results

Eighteen participants (77.3 ± 9.8 years; 44.4% females) were included. On average, we recruited 2.2 participants per month, and 35.3% of the individuals contacted were included. The intervention group had an attrition rate of 20% and mean adherence and compliance rates of 85.0 and 84.1%, respectively. The mean system usability score, measured with the system usability scale, was 71.7. High levels of exergame enjoyment, an increase in exergame enjoyment, and internalization of training motivation with large effect sizes (p = 0.03, r = 0.75 and p = 0.03, r = 0.74, respectively), as well as acceptable perceived usefulness, were observed. Preliminary data on the effects of the "Brain-IT" training are promising.

Conclusion

The feasibility and usability of the "Brain-IT" training are acceptable. However, frequent occurrences of technical problems and difficulties in using the exergame training system were identified as barriers to performing the "Brain-IT" training. To optimize feasibility, either improvements or alternative solutions are required in the hardware and software of the exergame used to implement the "Brain-IT" training. The "Brain-IT" training itself was well-accepted by older adults who have mNCD. Therefore, the effectiveness of the "Brain-IT" training concept should be investigated in future studies.

Trial registration

clinicaltrials.gov/ct2/show/NCT04996654.

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

Introduction

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

Method

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

Results

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

Discussion

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

Systematic review registration

PROSPERO, identifier: CRD42022291843.

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.

Effectiveness of lifestyle medicine on cognitive functions in mild cognitive impairments and dementia: A systematic review on randomized controlled trials

Mild cognitive impairment (MCI) and dementia are associated with lifestyle risk factors, making lifestyle medicine a potentially viable intervention for people with MCI and dementia. The present study aims to examine the effectiveness of lifestyle medicine on cognitive functions among people with MCI and dementia, by performing a systematic review and meta-analysis on randomized controlled trials (RCT). A systematic literature search was conducted to extract RCTs adopting lifestyle interventions of diet, exercise, and stress management or emotional well-being. Results showed that 65 studies were eligible. Exercise was the most promising lifestyle intervention that improved various cognitive functions among people with MCI and dementia, and was more effective in MCI than in dementia. Interventions on stress management or emotional well-being did not show a significant effect on people with MCI, and the evidence for people with dementia was insufficient to conclude. Similarly, due to the lack of RCTs on a healthy dietary pattern, the effectiveness of diet interventions was not examined. In conclusion, the exercise component of lifestyle medicine can be an effective and clinically significant intervention for protecting people with MCI and dementia against cognitive declines, especially when served as an early intervention at the stage of MCI.

Effectiveness of an Individualized Exergame-Based Motor-Cognitive Training Concept Targeted to Improve Cognitive Functioning in Older Adults With Mild Neurocognitive Disorder: Study Protocol for a Randomized Controlled Trial

BACKGROUND

Simultaneous motor-cognitive training is considered promising for preventing the decline in cognitive functioning in older adults with mild neurocognitive disorder (mNCD) and can be highly motivating when applied in the form of exergaming. The literature points to opportunities for improvement in the application of exergames in individuals with mNCD by developing novel exergames and exergame-based training concepts that are specifically tailored to patients with mNCD and ensuring the implementation of effective training components.

OBJECTIVE

This study systematically explores the effectiveness of a newly developed exergame-based motor-cognitive training concept (called "Brain-IT") targeted to improve cognitive functioning in older adults with mNCD.

METHODS

A 2-arm, parallel-group, single-blinded randomized controlled trial with a 1:1 allocation ratio (ie, intervention: control), including 34 to 40 older adults with mNCD will be conducted between May 2022 and December 2023. The control group will proceed with the usual care provided by the (memory) clinics where the patients are recruited. The intervention group will perform a 12-week training intervention according to the "Brain-IT" training concept, in addition to usual care. Global cognitive functioning will be assessed as the primary outcome. As secondary outcomes, domain-specific cognitive functioning, brain structure and function, spatiotemporal parameters of gait, instrumental activities of daily living, psychosocial factors, and resting cardiac vagal modulation will be assessed. Pre- and postintervention measurements will take place within 2 weeks before starting and after completing the intervention. A 2-way analysis of covariance or the Quade nonparametric analysis of covariance will be computed for all primary and secondary outcomes, with the premeasurement value as a covariate for the predicting group factor and the postmeasurement value as the outcome variable. To determine whether the effects are substantive, partial eta-squared (η²_p) effect sizes will be calculated for all primary and secondary outcomes.

RESULTS

Upon the initial submission of this study protocol, 13 patients were contacted by the study team. Four patients were included in the study, 2 were excluded because they were not eligible, and 7 were being informed about the study in detail. Of the 4 included patients, 2 already completed all premeasurements and were in week 2 of the intervention period. Data collection is expected to be completed by December 2023. A manuscript of the results will be submitted for publication in a peer-reviewed open-access journal in 2024.

CONCLUSIONS

This study contributes to the evidence base in the highly relevant area of preventing disability because of cognitive impairment, which has been declared a public health priority by the World Health Organization.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05387057; https://clinicaltrials.gov/ct2/show/NCT05387057.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/41173.

Does the combination of exercise and cognitive training improve working memory in older adults? A systematic review and meta-analysis

Background

Cognitive functioning is dependent on working memory and a decline in working memory is the main cause of cognitive aging. Many studies have suggested that physical exercise or cognitive intervention can effectively improve working memory in the elderly. However, it is still unknown whether a combination of exercise and cognitive training (CECT) is more effective than either intervention alone. The present systematic review and meta-analysis were undertaken to evaluate the effect of CECT on working memory in the elderly.

Methods

The review was registered in the International Prospective Systematic Review (PROSPERO, CRD42021290138). Systematic searches were conducted on Web of Science, Elsevier Science, PubMed and Google Scholar. The data were extracted according to the PICOS framework. Comprehensive meta-analysis (CMA) software was used to perform the meta-analysis, moderator analysis and publication bias testing.

Results

The current meta-analysis included 21 randomized controlled trials (RCT). Results showed that CECT had a significantly greater impact on working memory in older adults compared to no intervention groups (SMD = 0.29, 95% CI [0.14-0.44], p < 0.01), with no significant difference between CECT and exercise (SMD = 0.16, 95% CI [-0.04-0.35], p = 0.12) or cognitive intervention alone (SMD = 0.08, 95% CI [-0.13-0.30], p = 0.44). Furthermore, the positive effect of CECT was moderated by intervention frequency and cognitive state.

Conclusions

The CECT can effectively improve working memory of older adults, but the effect of CECT compared to single intervention needs to be further explored.

Gender-specific association of blood lipids and reproductive trajectory with cognitive impairment: A community based cross-sectional study from India

Background

Abnormal blood lipid levels in the general population and adverse reproductive events among women have been associated with cognitive impairment (CI). However, their relationship has not been extensively studied in community settings. Hence, this study aims to explore the association of CI with blood lipid levels in both sexes and reproductive events/trajectory among women.

Methods

A cross-sectional study was conducted among a North Indian rural population. A total of 808 adults were recruited through door-to-door household survey. Data on socio-demographic variables, reproductive profile of women, and cognitive impairment status were collected. Fasting blood sample was collected to estimate serum lipid profile. Multivariate logistic regression was performed to test for association.

Results

The study demonstrated a lack of association between lipid profile and cognitive impairment among males. Surprisingly, low HDL-C among females was found to be protective against moderate/severe cognitive impairment (value of p = 0.049). Further, menopausal women and those having five or higher live births were found to be at higher risk of CI than pre-menopausal women and those with 1-2 live births, respectively.

Conclusion

The present study hints toward a gender-specific association of blood lipid levels with CI. Further, higher live births and menopause appear to be important risk factors for CI among women.

Effects of virtual reality combined cognitive and physical interventions on cognitive function in older adults with mild cognitive impairment: A systematic review and meta-analysis

OBJECTIVE

Combined cognitive and physical interventions based on virtual reality may help delay the progression of MCI to dementia or prevent dementia. However, their efficacy is less well studied compared to pharmaceutical treatments. The purpose of this review was to evaluate the effects of cognitive and physical interventions based on virtual reality on cognitive function (global cognition, memory or executive function/attention) of older adults with mild cognitive impairment.

METHODS

We searched the PubMed, Web of Science, Scopus, Embase, Cochrane Library, PsycINFO, CINAHL and IEEE from inception to 13 May 2021. Only randomized controlled trials which incorporated virtual reality cognitive and physical components targeted to individuals with mild cognitive impairment were eligible. Two researchers independently conducted document retrieval, study selection, data extraction, and methodological quality evaluation.

RESULT

7 randomized controlled trials were included in a total of 8 articles. No studies were rated as having a "high" risk of overall bias. The results of a meta-analysis showed that VR combined cognitive and physical interventions enhanced the global cognitive (MD = 2.66, 95% CI = 1.79-3.54, P = 0.03, I ² = 68%) abilities of older adults with mild cognitive impairment. The meta-analysis indicated that after virtual reality combined cognitive and physical interventions, effects on memory (SMD = -0.03, 95% CI = -0.60 to 0.55, P = 0.78, I ² = 0%) and executive function/attention (SMD = -0.19, 95% CI = -0.74 to 0.36, P = 0.09, I ² = 53%) were not statistically significant.

CONCLUSIONS

The present meta-analysis verifies the potential rehabilitative effects of virtual reality combined cognitive and physical interventions for older adults with mild cognitive impairment. More research is also needed to determine the optimal intensity and timing of interventions in the future.

Combined Tai Chi and cognitive interventions for older adults with or without cognitive impairment: A meta-analysis and systematic review

BACKGROUND AND PURPOSE

Evidence from the field of cognitive interventions indicates that nonpharmaceutical interventions seem more promising in enhancing cognition. The number of clinical trials that examine the cognitive benefits of combined physical exercise with cognitive intervention on older adults has recently increased. Tai Chi (TC) has been recommended as an effective and safe exercise for older adults aged 60 and over. However, there is a lack of conclusion about whether combined TC with cognitive interventions can show more benefits than a single intervention for older adults. Thus, this review aimed to evaluate the effects of combined TC and cognitive interventions on older adults.

METHODS

PubMed, Embase, PsycINFO, and Web of Science were searched for English peer-reviewed papers from inception until November 12, 2021. Data were extracted by two independent reviewers.

RESULTS

A total of 1524 records were generated and nine studies were included. The pooled results showed that combined TC and cognitive interventions showed significantly large gains on memory [standardised mean difference (SMD) = 0.87, 95% confidence interval (CI): (0.01, 1.74), P 0.05], moderate gains on cognition [SMD = 0.74, 95% CI:(0.19, 1.29), P 0.05], and small size effects on balance. No statistically significant difference was found in executive function, depression, risk of falls, or well-being.

CONCLUSION

Combined TC and cognitive interventions have positive effects on improving cognition and balance in older adults, but their superiority over the single intervention, as well as their additional effects on the physical and psychological function, are required further investigation.

Exercise Training for Mild Cognitive Impairment Adults Older Than 60: A Systematic Review and Meta-Analysis

Background:

The prevalence of mild cognitive impairment (MCI) continues to increase due to population aging. Exercise has been a supporting health strategy that may elicit beneficial effects on cognitive function and prevent dementia.

Objective:

This study aimed to examine the effects of aerobic, resistance, and multimodal exercise training on cognition in adults aged > 60 years with MCI.

Methods:

We searched the Cochrane Library, PubMed, and Embase databases and ClinicalTrials.gov (https://clinicaltrials.gov) up to November 2021, with no language restrictions. We included all published randomized controlled trials (RCTs) comparing the effect of exercise programs on cognitive function with any other active intervention or no intervention in participants with MCI aged > 60 years.

Results:

Twelve RCTs were included in this review. Meta-analysis results revealed significant improvements in resistance training on measures of executive function (p < 0.05) and attention (p < 0.05); no significant differences were observed between aerobic exercise and controls on any of the cognitive comparisons.

Conclusion:

Exercise training had a small beneficial effect on executive function and attention in older adults with MCI. Larger studies are required to examine the effects of exercise and the possible moderators.

The Impact of COVID-19 Infection on Cognitive Function and the Implication for Rehabilitation: A Systematic Review and Meta-Analysis

There is mounting evidence that patients with severe COVID-19 disease may have symptoms that continue beyond the acute phase, extending into the early chronic phase. This prolonged COVID-19 pathology is often referred to as 'Long COVID'. Simultaneously, case investigations have shown that COVID-19 individuals might have a variety of neurological problems. The accurate and accessible assessment of cognitive function in patients post-COVID-19 infection is thus of increasingly high importance for both public and individual health. Little is known about the influence of COVID-19 on the general cognitive levels but more importantly, at sub-functions level. Therefore, we first aim to summarize the current level of evidence supporting the negative impact of COVID-19 infection on cognitive functions. Twenty-seven studies were included in the systematic review representing a total of 94,103 participants (90,317 COVID-19 patients and 3786 healthy controls). We then performed a meta-analysis summarizing the results of five studies (959 participants, 513 patients) to quantify the impact of COVID-19 on cognitive functions. The overall effect, expressed in standardized mean differences, is -0.41 [95%CI -0.55; -0.27]. To prevent disability, we finally discuss the different approaches available in rehabilitation to help these patients and avoid long-term complications.

Associations of Multidomain Interventions With Improvements in Cognition in Mild Cognitive Impairment: A Systematic Review and Meta-analysis

IMPORTANCE

Older adults with mild cognitive impairment (MCI) have the highest risk of progressing to dementia. Evidence suggests that nonpharmacological, single-domain interventions can prevent or delay progressive declines, but it is unclear whether greater cognitive benefits arise from multidomain interventions.

OBJECTIVE

To determine whether multidomain interventions, composed of 2 or more interventions, are associated with greater improvements in cognition among older adults with MCI than a single intervention on its own.

DATA SOURCES

MEDLINE, Embase, PsycInfo, AgeLine, CINAHL, and Cochrane Central Register of Controlled Trials were systematically searched from database inception to December 20, 2021.

STUDY SELECTION

Included studies contained (1) an MCI diagnosis; (2) nonpharmacological, multidomain interventions that were compared with a single active control; (3) older adults aged 65 years and older; and (4) randomized clinical trials.

DATA EXTRACTION AND SYNTHESIS

Data were screened and extracted by 3 independent reviewers. Following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, random-effects meta-analyses were used to calculate effect sizes from the standardized mean difference (SMD) and 95% CIs.

MAIN OUTCOMES AND MEASURES

Postintervention cognitive test scores in 7 cognitive domains were compared between single-domain and multidomain groups. Exposure to the intervention was analyzed.

RESULTS

A total of 28 studies published between 2011 and 2021, including 2711 older adults with MCI, reported greater effect sizes in the multidomain group for global cognition (SMD, 0.41; 95% CI, 0.23-0.59; P < .001), executive function (SMD, 0.20; 95% CI, 0.04-0.36; P = .01), memory (SMD, 0.29; 95% CI, 0.14-0.45; P < .001), and verbal fluency (SMD, 0.30; 95% CI, 0.12-0.49; P = .001). The Mini-Mental State Examination (SMD, 0.40; 95% CI, 0.17-0.64; P < .001), category verbal fluency test (SMD, 0.34; 95% CI, 0.13-0.56; P = .002), Trail Making Test-B (SMD, 0.46; 95% CI, 0.13-0.80; P = .007), and Wechsler Memory Scale-Logical Memory I (SMD, 0.47; 95% CI, 0.15-0.80; P < .001) and II (SMD, 0.26; 95% CI, 0.07-0.45; P < .001) favored the multidomain group. Exposure to the intervention varied between studies: the mean (SD) duration was 71.3 (36.0) minutes for 19.8 (14.6) weeks with sessions taking place 2.5 (1.1) times per week, and all interventions lasted less than 1 year.

CONCLUSIONS AND RELEVANCE

In this study, short-term multidomain interventions (<1 year) were associated with improvements in global cognition, executive function, memory, and verbal fluency compared with single interventions in older adults with MCI.

Effects of Traditional Chinese Exercises on Cognitive Function in Older Adults With Mild Cognitive Impairment: A Systematic Review and Meta-Analysis

Background

Recently, considerable research has been conducted to study the effects of traditional Chinese exercises (TCEs) on cognitive function in older adults with MCI. We completed a comprehensive systematic review and meta-analysis to assess the efficacy of TCEs on cognitive function in this population.

Methods

A search strategy based on the PICOS principle was used to find the literatures in the databases of PubMed, Web of Science, MEDLINE, SPORT-Discus, PsycINFO, Cochrane Central Register of Controlled Trials, Ovid. The quality and risk of bias in the studies were independently assessed by two researchers.

Results

Nine trials with 1,290 participants were included. The effect size of TCEs on global cognitive function was small (SMD = 0.29, 95% CI 0.15-0.44, p < 0.001) when compared to the active control and was moderate (SMD = 0.58, 95% CI 0.21-0.94, p = 0.002) compared to the inactive control; statistically significant effects were also found for short-term memory (SMD = 0.22, 95% CI 0.05-0.39, p = 0.013), long-term memory (SMD = 0.53, 95% CI 0.20-0.86, p = 0.002), shifting (SMD = -0.39, 95% CI -0.54 to -0.25, p < 0.001), language ability (SMD = 0.32, 95% CI 0.13-0.51, p = 0.001), visuospatial perception (SMD = 0.31, 95% CI 0.15-0.46, p < 0.001).

Conclusion

This meta-analysis provides clinicians with moderate evidence to recommend that TCEs hold potential to enhance both global cognitive function and multiple domains of cognitive function, which, however, needs to be confirmed and further examined in futures studies. The results of this work provide critical knowledge for the design of future studies implementing TCEs as well as its clinical practice. Future RCTs with rigorous designs are needed to help obtain more definitive conclusions on the effects of TCEs on cognitive function in older adults with MCI.

The estimated prevalence of no reported dementia-related diagnosis in older Americans living with possible dementia by healthcare utilization

BACKGROUND

Screening for dementia in relevant healthcare settings may help in identifying low cognitive functioning for comprehensive cognitive assessments and subsequent dementia treatment after diagnosis.

AIMS

This study sought to estimate the prevalence of no reported dementia-related diagnosis in a nationally-representative sample of older Americans with a cognitive impairment consistent with dementia (CICD) by healthcare utilization.

METHODS

The unweighted analytical sample included 1514 Americans aged ≥ 65 years that were identified as having a CICD without history of stroke, cancers, neurological conditions, or brain damage who participated in at least one-wave of the 2010-2016 waves of the Health and Retirement Study. An adapted Telephone Interview of Cognitive Status assessed cognitive functioning. Those with scores ≤ 6 had a CICD. Dementia-related diagnosis was self-reported. Respondents indicated if they visited a physician, received home healthcare, or experienced an overnight nursing home stay in the previous two years.

RESULTS

The prevalence of no reported dementia-related diagnosis in persons with a CICD who visited a physician was 89.9% (95% confidence interval (CI): 85.4%-93.1%). Likewise, the prevalence of no reported diagnosis in those with a CICD who received home healthcare was 84.3% (CI: 75.1-90.5%). For persons with a CICD that had an overnight nursing home stay, the prevalence of no reported dementia-related diagnosis was 83.0% (CI: 69.1-91.4%).

DISCUSSION

Although the prevalence of no reported dementia-related diagnosis in individuals with a CICD differed across healthcare settings, the prevalence was generally high nonetheless.

CONCLUSIONS

We recommend increased awareness and efforts be given to dementia screenings in various clinical settings.