Comparison of Cognitive Intervention Strategies for Older Adults With Mild to Moderate Alzheimer's Disease: A Bayesian Meta-analytic Review

Combined exercise and cognitive interventions for adults with mild cognitive impairment and dementia: A systematic review and network meta-analysis

BACKGROUND

Exercise and cognitive interventions are beneficial for adults with preclinical and clinical dementia, but it is unclear whether the combination of these two components could generate synergistic benefits and what intervention designs would optimize this effect.

OBJECTIVES

This review aims to compare the effects of combined exercise and cognitive interventions on cognitive, psychological, functional outcomes, and health-related quality of life with the corresponding single approach and control groups in adults with mild cognitive impairment and dementia. It also aims to identify the optimal intervention design and factors affecting treatment effects.

METHODS

A comprehensive search was conducted in ten databases from inception to 23rd November 2022. The methodological quality of studies was evaluated by the Cochrane risk of bias tool. Pairwise meta-analyses were performed to assess the effects of combined interventions relative to the single type of intervention and control groups, with further subgroup analysis to explore the factors affecting treatment effects. Network meta-analyses were used to identify the optimal intervention components.

RESULTS

Twenty-nine randomized controlled trials involving 2910 participants were included. The results of pairwise meta-analyses indicated that combined interventions were superior to exercise in improving response inhibition, working memory, and delayed recall, but were not superior to cognitive interventions in all outcomes. Combined interventions were superior to active/passive controls in improving global cognition, response inhibition, immediate recall, delayed recall, category fluency, processing speed, and visuospatial ability. Influences of the clinical severity of dementia (mild cognitive impairment vs dementia), combination format (sequential vs simultaneous combination), mode of delivery (group-based vs individual-based vs mixed), training duration (short: ≤12 weeks vs medium: 13-24 weeks vs long: >24 weeks), and types of control (active vs passive control) were not detected. The network meta-analysis results indicated that the optimal intervention components varied across different outcomes, with multimodal exercise combining cognitive training demonstrated the greatest effects among all other combined or single component interventions in improving global cognition.

CONCLUSIONS

This review suggests the advantage of combined interventions over exercise with comparable effects when compared with cognitive interventions in the population with mild cognitive impairment and dementia. Full scale multi-arm randomized controlled trials to compare the effects of combined interventions with cognitive interventions are warranted.

Impact of discontinuing non-pharmacological interventions on cognitive impairment in dementia patients by COVID-19 lockdown. A pilot observational, longitudinal, retrospective study carried out in an adult day center in Spain during the COVID-19 pandemic

Background

The lockdown imposed during the COVID-19 pandemic led to social isolation and prevented patients with dementia from receiving a suite of non-pharmacological interventions (NPIs) that prevent cognitive decline. This discontinuation of NPIs could substantially affect the mental health status of people with dementia in social care settings, such as adult day care centers (ADCs).

Propose

The study aimed to evaluate the effects of the COVID-19 lockdown on mental health and cognitive impairment in patients with dementia who could not attend their usual ADCs and did not receive our NPIs, based on World Health Organization (WHO) Guidelines.

Methods

Observational, longitudinal, retrospective study carried out in an adult day center in Spain and reported it in accordance with the Strengthening Reporting of Observational Studies in Epidemiology (STROBE) statement. Cognitive status was assessed using the Mini-Mental State Examination (MMSE) in 80 patients attending the ADC of the "Leonese Association of Dementia Patients" (León, Spain), who had been evaluated with this instrument before the COVID-19 lockdown.

Results

We observed a 0.4-point decrease in MMSE score/month (IQR = 1.4) during lockdown versus a 0.1-point decrease/month (IQR = 0.3) before this period (p = 0.038). Notably, this translated to >10-point decreases in MMSE score/year in 33.8% of participants during lockdown versus 5.5% earlier (p < 0.001). No statistically significant associations (p < 0.05) were found between the individual characteristics of the caregivers and the occurrence of the event.

Conclusion

The reported declines in MMSE scores reveal a significant acceleration of cognitive decline during the period of inactivity. This could suggest that our NPIs, focused on slowing cognitive decline, are beneficial and, therefore, necessary in patients with dementia.

Effects of cognitive stimulation therapy on patients with dementia: An umbrella review of systematic reviews and meta-analyses

BACKGROUND

Dementia is characterized by significant cognitive decline that results in disturbance of daily activities. Increasing number of meta-analyses has examined the efficacy of cognitive stimulation therapy (CST) for dementia. However, there is a lack of comprehensive reports that specifically discuss the strength of evidence to support CST for dementia.

PURPOSE

This study aimed to summarize evidence regarding the efficacy of CST on people with dementia.

DESIGN

Umbrella review of systematic reviews and meta-analyses.

METHODS

We searched Cochrane Library, PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang Data, China Biology Medicine disc (CBMdisc), and VIP databases from inception to December 31, 2022. The methodological quality of the identified studies was assessed using A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2). Studies scoring 9-12 (moderate quality) points or higher were further analyzed using Grades of Recommendations Assessment, Development and Evaluation (GRADE) principles.

RESULTS

A total of 14 systematic reviews and meta-analyses were included in the umbrella review. The methodological quality of most included reviews was rated as moderate according to AMSTAR 2 rating system. In these studies, we summarized the characteristics of the content, providers, frequency, period and setting of CST, and examined eight health outcomes related to CST, including cognition, depression, behavioral symptoms, quality of life (QoL), activities of daily living (ADL), language and communication, anxiety, and memory. Eleven studies with low to high rating of overall confidence (OC) consistently reported that CST could significantly improve cognition of people with dementia, including high-quality supporting evidence. However, the effect of CST on other health outcomes for people with dementia (e.g., depression, behavioral symptoms, QoL, ADL) is inconsistent, with low- to moderate-quality evidence ratings. Compared with the above results, few studies have reported the effects of CST on communication, anxiety, and memory for people with dementia.

CONCLUSIONS

In the future, the design and reporting of systematic reviews and meta-analyses should incorporate high-quality research metrics in accordance with AMSTAR 2 criteria. The current review supports CST as an effective treatment for improving cognitive function in patients with dementia. Multi-component interventions are more effective than single-component interventions and need to be delivered regularly.

REGISTRATION

The protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) database (CRD42022364259).

Air Pollution: A Silent Key Driver of Dementia

In 2017, the Lancet Commission on Dementia Prevention, Intervention, and Care included air pollution in its list of potential risk factors for dementia; in 2018, the Lancet Commission on Pollution concluded that the evidence for a causal relationship between fine particulate matter (PM) and dementia is encouraging. However, few interventions exist to delay or prevent the onset of dementia. Air quality data are becoming increasingly available, and the science underlying the associated health effects is also evolving rapidly. Recent interest in this area has led to the publication of population-based cohort studies, but these studies have used different approaches to identify cases of dementia. The purpose of this article is to review recent evidence describing the association between exposure to air pollution and dementia with special emphasis on fine particulate matter of 2.5 microns or less. We also summarize here the proposed detailed mechanisms by which air pollutants reach the brain and activate the innate immune response. In addition, the article also provides a short overview of existing limitations in the treatment of dementia.

Non-pharmacological interventions for behavioral and psychological symptoms of dementia: A systematic review and network meta-analysis protocol

Introduction

Dementia patients often experience behavioral and psychological symptoms (BPSD), which severely affect their quality of life and activities of daily living. Non-pharmacological interventions are effective in treating BPSD, according to multiple clinical trials and systematic reviews. However, the optimal non-pharmacological treatment remains controversial. Therefore, the study aims to evaluate and compare multiple non-pharmacological methods for treating BPSD in order to identify the optimal non-pharmacological intervention.

Objective

This study aims to perform a systematic review and network meta-analysis of evidence on non-pharmacological interventions in the treatment of BPSD, which may potentially guide future research and clinical decisions.

Methods

In order to select potentially relevant randomized controlled trials (RCTs), 10 academic databases and 3 clinical trial registries will be systematically searched from inception until the 1 October 2022. Two researchers will independently extract information from eligible articles. The primary outcome is the severity of BPSD. Herein, Pairwise and Bayesian network meta-analyses will be conducted utilizing STATA 15.0 and ADDIS 1.16.8. Evidence quality will be assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE).

Results

Results from this study will be published in peer-reviewed journals or conference reports.

Discussion

In this study, we aim to comparatively assess the efficacy of various non-pharmacological treatments for BPSD. Findings from this review will help clinicians to make evidence-based treatment decisions.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/], identifier [CRD42022352095].

Cognitive training for elderly patients with early Alzheimer’s disease in the Qinghai-Tibet Plateau: A pilot study

BACKGROUND

Alzheimer’s disease (AD) influences the social and economic quality of life of older adult patients and their families.

AIM

To explore the efficacy of cognitive training in clinical nursing for patients with early AD residing in the plateau area.

METHODS

This pilot study was conducted in patients with early AD treated in the Geriatric Department of the Qinghai Provincial People’s Hospital between August 2019 and March 2021. The patients were divided into a cognitive training group and a conventional nursing group using the random number table method. Patients in the conventional nursing group received conventional nursing, whereas the patients in the cognitive training group received the new nursing intervention. The mini-mental state examination (MMSE) and activities of daily living (ADL) scales were used to compare the cognitive ability and daily activities, respectively, between the two groups before and after the intervention.

RESULTS

Sixty patients were enrolled in this study, with 30 patients in the cognitive training group and conventional nursing group, respectively. The MMSE and ADL scores were significantly higher in the cognitive training group than in the conventional nursing group after the intervention (MMSE: 25.11 ± 2.02 vs 22.26 ± 1. 23, P = 0.032; ADL: 68.72 ± 4.86 vs 60.16 ± 2.27, P = 0.018).

CONCLUSION

The application of cognitive training in clinical nursing for patients with early AD could improve both their cognitive ability and ADL. This method could be applied in clinical practice to manage cognitive dysfunction in patients with early AD.

A Conceptual View of Cognitive Intervention in Older Adults With and Without Cognitive Decline-A Systemic Review

Background: Dementia is the one of the most common and prominent disease in the elderly person that results in the Cognitive interventions. In this study, we aim to conceptualize the cognitive intervention for older adults with and without cognitive dysfunction and to clarify the heterogeneity existing in this literature field by determining the main variables implicated. Methods: We conducted a study analysis using previous literature highlighting the significant data reporting empirical results from cognitive intervention for healthy older adults and other seniors with different types of dementia. Each paper was reviewed in terms of compensatory cognitive training, cognitive remediation, enrichment, cognitive activation, brain training, cognitive stimulation, cognitive training, and cognitive rehabilitation. The research analysis was performed following rigorous inclusion and exclusion criteria with the purpose of collecting relevant answers to our research questions. Results: We included a total of 168 studies in our review. Our findings indicated heterogeneity regarding methods, concepts, and procedures. Additionally, the values were integrated using different information existing in this field. Conclusion: In conclusion, we highlighted that this is the first review that clarify the discrepancy of various existing definitions, methods, and procedures, as well as the overlapping information in the cognitive interventions.

The Effect of Cognitive Intervention on Cognitive Function in Older Adults With Alzheimer's Disease: A Systematic Review and Meta-Analysis

Cognitive intervention includes cognitive stimulation, cognitive training, and cognitive rehabilitation. This systematic review was performed to re-assess the efficacy of cognitive intervention for the patients with Alzheimer's disease (AD). Twenty studies (2012 participants) were eventually included. For global cognitive function, the combined mean difference (MD) in eight studies was 1.67 (95% Confidence Interval: 0.45, 2.89, p = 0.007; Q = 33.28, df = 8, p < 0.0001, τ² = 2.17, I² = 76%) for the short term. The pooled standardized mean difference (SMD) of six RCTs was 1.61 (95% Confidence Interval: 0.65, 2.56, p = 0.0009; Q = 127.66, df = 6, p < 0.00001, τ² = 1.56, I² = 95%) for the medium term. The pooled SMD of seven studies was 0.79 (95% Confidence Interval: 0.33, 1.25, p = 0.0008; Q = 35.10, df = 7, p < 0.0001, τ² = 0.33, I² = 80%) for the long term. For depression, the pooled SMD of two trials was -0.48 (95% Confidence Interval: -0.71, -0.24; p < 0.0001, I² = 4%) for the short term. Cognitive training may show obvious improvements in global cognitive function whether after short, medium, or long-term interventions and in depression after short term intervention. However, the positive effect of the intervention on general cognitive function or depression did not seem to persist after intervention ended. There is still a lack of reliable and consistent conclusions relevant to the effect of cognitive stimulation and cognitive rehabilitation on observed outcomes, cognitive training for memory or other non-cognitive outcomes. PROSPERO registration number: CRD42019121768.

Effect of early cognitive interventions on delirium in critically ill patients: a systematic review

PURPOSE

A systematic review of the literature was conducted to determine the effects of early cognitive interventions on delirium outcomes in critically ill patients.

SOURCE

Search strategies were developed for MEDLINE, EMBASE, Joanna Briggs Institute, Cochrane, Scopus, and CINAHL databases. Eligible studies described the application of early cognitive interventions for delirium prevention or treatment within any intensive care setting. Study designs included randomized-controlled trials, quasi-experimental trials, and pre/post interventional trials. Two reviewers independently extracted data and assessed risk of bias using Cochrane methodology.

PRINCIPAL FINDINGS

Four hundred and four citations were found. Seven full-text articles were included in the final review. Six of the included studies had an overall serious, high, or critical risk of bias. After application of cognitive intervention protocols, a significant reduction in delirium incidence, duration, occurrence, and development was found in four studies. Feasibility of cognitive interventions was measured in three studies. Cognitive stimulation techniques were described in the majority of studies.

CONCLUSION

The study of early cognitive interventions in critically ill patients was identified in a small number of studies with limited sample sizes. An overall high risk of bias and variability within protocols limit the utility of the findings for widespread practice implications. This review may help to promote future large, multi-centre trials studying the addition of cognitive interventions to current delirium prevention practices. The need for robust data is essential to support the implementation of early cognitive interventions protocols.

A 4-Item Case-Finding Tool to Detect Dementia in Older Persons

OBJECTIVES

Brief cognitive tests are recommended in clinical services outside of specialized memory clinics as case-finding tools to reduce the diagnostic gap of dementia. Although the Montreal Cognitive Assessment (MoCA) is among the most widely used brief tests in specialized memory clinics, its length precludes routine use in nonspecialty clinics. This study investigated whether a small subset of MoCA would suffice to match the performance of the full MoCA in detecting dementia and, hence, be useful in nonspecialty clinics.

DESIGN

Cross-sectional test research.

SETTING

Alzheimer's Disease Centers across the United States.

PARTICIPANTS

Participants age ≥65 years (n = 8773).

MEASURES

Participants completed MoCA and were evaluated for dementia. The study sample was split into 2: the derivation sample (n = 4386) was used to develop a short variant of MoCA that best distinguish dementia (using the best-subset-approach with 10-fold cross-validation), while the validation sample (n = 4387) verified its actual performance using area under the receiver operating characteristic-curve (AUC).

RESULTS

A 4-item cognitive test was identified, comprising Clock-drawing, Tap-at-letter-A, Orientation, and Delayed-recall. It demonstrated excellent performance in distinguishing dementia from nondementia (AUC 94.2%) and was comparable to that of MoCA (AUC 93.8%), even across education subgroups. It explained 85.9% of the variability in MoCA and had scores that could be mapped to MoCA with reasonable precision. At the optimal cut-off score of <10, it demonstrated 87.9% sensitivity and 87.6% specificity in detecting dementia.

CONCLUSIONS AND IMPLICATIONS

Using rigorous methods, this study developed a brief cognitive test that is free of charge, takes <5 minutes to complete, covers the key cognitive domains, and has standardized instructions to allow its administration even by nonphysicians. This brief test is well suited as a case-finding tool in nonspecialty clinics (such as in primary care and geriatric clinics) and may improve care-integration with specialized memory clinics that utilize MoCA.

Non-pharmacological therapeutic strategy options for patients with dementia based on cognitive function-A Bayesian network meta-analysis of randomized controlled trials

Dementia represents one of the most common neurodegenerative disorders in older adults. However, it is still unclear whether non-pharmacological therapies (NPTs) are effective or not and which treatment should be preferred. We applied a series of search strategies to identify eligible randomized controlled trials on 1st October, 2018, investigating the effects of NPTs of dementia in the older persons. Pairwise and network meta-analyses were sequentially performed. A total of 31 trials were included, which enrolled 1895 participants and 7 NPTs. Compared with control group, all the NPTs included were statistically beneficial to cognitive function, and our study indicated Comprehensive Therapy(CT) [the surface under the cumulative ranking curve (SUCRA = 92.42%)] might be the best choice for dementia patients. Our study suggests CT might be the optimal NPT for improving the cognitive function of dementia patients. However, the above conclusions need to be further analyzed.

Cognitive interventions for mild cognitive impairment and dementia: An overview of systematic reviews

PURPOSE

Conducting an overview of systematic reviews (SRs)/Meta analyses (MAs) to assess the effectiveness of cognitive interventions on participants with mild cognitive impairment (MCI) or dementia and evaluate the methodological quality of SRs/MAs.

METHODS

PubMed, EMBASE, Cochrane library, Web of science, China National Knowledge Infrastructure (CNKI) and Chinese Biomedical Databases (CBM) were systematically searched from inception to January 1, 2019 to identify SRs/MAs. Three reviewers independently screened the articles, extracted data and assessed the quality of the included studies according to the Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR-2), the Grading of Recommendations Assessment Development and Evaluation (GRADE) was used to evaluate the quality of evidence.

RESULTS

A total of 22 reviews were included. New meta-analyses (36 RCTs) showed that cognitive interventions were more effective than routine therapies for the alleviation of MCI and dementia symptoms (SMD: 0.62; 95%CI: 0.47, 0.78; I² = 53.9%). The results of AMSTAR-2 showed that the methodological quality of most included studies was critically low, and two reviews were low quality. The lowest score was item 10, none of reviews reported on the sources of funding for the included studies. Followed by the "provide a list of excluded studies and justify the exclusions" item with only one (4.5%) reviews conforming to this item. Results of GRADE manifested that moderate quality evidence was provided in 11 reviews (39.3%), 12 (42.9%) were low quality and 5 (17.8%) were very low.

CONCLUSION

The present SRs/MAs indicated that persons with MCI or dementia could benefit from cognitive interventions. Future trial designs should focus on measuring changes in individual specific cognitive functions. More high-quality evidence is needed to further determine the effectiveness of cognitive interventions.

Developing a Brief Neuropsychological Battery for Early Diagnosis of Cognitive Impairment

OBJECTIVES

Early diagnosis of cognitive impairment is increasingly emphasized in the literature to facilitate timely preventive interventions. Although bedside cognitive tests such as the Montreal Cognitive Assessment (MoCA) are widely used for such early diagnostic purposes, they may not have comparable performance to a full neuropsychological battery (FNB) in diagnosing early cognitive impairment. This study investigated whether a small subset of neuropsychological tests can be added on to MoCA to match its performance to that of the FNB in discriminating mild cognitive impairment and dementia (MCI/dementia) from normal cognition.

DESIGN

Cross-sectional diagnostic study.

SETTING

Alzheimer's Disease Centers across the United States.

PARTICIPANTS

Older participants (≥50 years) who completed MoCA and the FNB (N = 9187).

MEASURES

The study sample was split into two: the derivation sample (n = 1837) was used to develop a brief neuropsychological battery that best discriminated MCI/dementia (using the best-subset approach with 10-fold cross-validation); while the validation sample (n = 7350) verified its actual performance in discriminating MCI/dementia.

RESULTS

A 3-item neuropsychological battery was identified, comprising MoCA, Benson Complex Figure Recall, and Craft Story 21 Delayed Recall. It had excellent performance in discriminating MCI/dementia from normal cognition (area under the receiver operating characteristic curve [AUROC] 90.0%, 95% confidence interval [CI] 89.2%-90.7%), which was comparable to that of the FNB (AUROC 88.4%, 95% CI 87.6%-89.2%). By contrast, MoCA alone had significantly worse AUROC (86.9%, 95% CI 86.0%-87.7%) than that of the FNB.

CONCLUSIONS/IMPLICATIONS

Using rigorous methods, this study developed a brief neuropsychological battery that maintained the brevity of a bedside cognitive test, while rivaling the diagnostic performance of an FNB in early cognitive impairment. This brief battery offers a viable alternative when the FNB is needed but cannot be feasibly administered in nonspecialty clinics. It can have a wider health systems effect of improving patients' access to accurate diagnosis in early cognitive impairment and facilitating timely interventions to delay the progression of cognitive impairment.

The Optimal Short Version of Montreal Cognitive Assessment in Diagnosing Mild Cognitive Impairment and Dementia

OBJECTIVES

While various short variants of the Montreal Cognitive Assessment (MoCA) have been developed, they have not been compared among each other to determine the most optimal variant for routine use. This study evaluated the comparative performance of the short variants in identifying mild cognitive impairment or dementia (MCI/dementia).

DESIGN

Baseline data of a cohort study.

SETTING

Alzheimer's Disease Centers across the United States.

PARTICIPANTS

Participants aged ≥50 years (n = 4606), with median age 70 (interquartile range 65-76).

MEASURES

Participants completed MoCA and were evaluated for MCI/dementia. The various short variants of MoCA were compared in their performance in discriminating MCI/dementia, using areas under the receiver operating characteristic curve (AUCs).

RESULTS

All 7 short variants of MoCA had acceptable performance in discriminating MCI/dementia from normal cognition (AUC 87.7%-91.0%). However, only 2 variants by Roalf et al (2016) and Wong et al (2015) demonstrated comparable performance (AUC 88.4-88.9%) to the original MoCA (AUC 89.3%). Among the participants with higher education, only the variant by Roalf et al had similar AUC to the original MoCA. At the optimal cut-off score of <25, the original MoCA demonstrated 84.4% sensitivity and 76.4% specificity. In contrast, the short variant by Roalf et al had 87.2% sensitivity and 72.1% specificity at its optimal cut-off score of <13.

CONCLUSIONS/IMPLICATIONS

The various short variants may not share similar diagnostic performance, with many limited by ceiling effects among participants with higher education. Only the short variant by Roalf et al was comparable to the original MoCA in identifying MCI or dementia even across education subgroups. This variant is one-third the length of the original MoCA and can be completed in <5 minutes. It provides a viable alternative when it is not feasible to administer the original MoCA in clinical practice and can be especially useful in nonspecialty clinics with large volumes of patients at high risk of cognitive impairment (such as those in primary care, geriatric, and stroke prevention clinics).