Effect of unawareness on rehabilitation outcome in a randomised controlled trial of multicomponent intervention for patients with mild Alzheimer's disease

Efficacy of Nonpharmacological Interventions in Cognitive Impairment: Systematic Review And Network Meta-Analysis

INTRODUCTION

There is currently no known cure for cognitive impairment, which highlights the need to explore other ways of managing this condition. This topic has recently become an area of active research. However, the availability of nonpharmacological options poses a challenge when trying to determine the best treatment for improving cognitive function.

METHODS

We conducted a systematic review and a Bayesian network meta-analysis to compare the effects of nonpharmacological interventions on global cognition in patients with mild cognitive impairment and dementia. The nonpharmacological interventions were classified as aerobic exercise, strength exercise, multicomponent physical exercise, other physical exercises, tai chi, mind-body exercises, traditional cognitive rehabilitation, computer-based cognitive rehabilitation, occupational therapy, music therapy, physical-cognitive rehabilitation, and reminiscence therapy.

RESULTS

Physical-cognitive rehabilitation emerged as the most effective nonpharmacological intervention for enhancing global cognition in patients with unspecified cognitive impairment and dementia, whereas occupational therapy focused on dual-task interventions was found to be the most effective nonpharmacological intervention for mild cognitive impairment.

CONCLUSION

These results underscore the importance of adopting a dual approach to managing cognitive impairment, integrating both cognitive and physical rehabilitation within the same intervention.

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

OBJECTIVES

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

METHOD

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

RESULTS

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

CONCLUSION

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

Comparison of Cognitive Intervention Strategies for Individuals With Alzheimer's Disease: A Systematic Review and Network Meta-analysis

Accumulating evidence has shown the effectiveness of cognitive interventions, which can be divided into cognitive training (CT), cognitive stimulation (CS), cognitive rehabilitation (CR), and combined interventions (i.e., cognitive interventions combined with other non-pharmacological interventions such as physical exercise), in individuals with Alzheimer's disease (AD). However, the effectiveness of cognitive interventions varies greatly among studies and more comprehensive studies are required. We aimed to evaluate whether the current evidence shows that cognitive interventions are effective at improving cognition, neuropsychiatric symptoms, depression, quality of life, and basic activities of daily living among individuals with possible or probable AD. Randomized controlled trials of all types of cognitive intervention were identified for inclusion in pairwise and network meta-analyses. There was a moderate and statistically significant post-intervention improvement in global cognition among individuals with AD for all types of cognitive intervention compared to control interventions (39 studies, g = 0.43, 95% CI: 0.28 to 0.58, p < 0.01; Q = 102.27, df = 38, p < 0.01; I2 = 61.97%, τ2 = 0.13). Regarding the specific types of cognitive intervention, combined interventions had the highest surface under the cumulative ranking curve (SUCRA) value (90.7%), followed by CT (67.8%), CS (53.4%), and lastly CR (28.9%). Significant effects of cognitive interventions were also found for working memory, verbal memory, verbal fluency, confrontation naming, attention, neuropsychiatric symptoms, basic activities of daily living, and quality of life.

[Conscience des déficits dans le cadre de la maladie d'Alzheimer : représentations et vécu des professionnels soignants]

La qualité des soins apportés aux personnes vivant avec la maladie d'Alzheimer (MA) dépend en partie de la capacité des professionnels à déterminer le degré de conscience de la maladie chez les patients. La présente recherche s'est intéressée aux représentations des soignants concernant la conscience des troubles chez les résidents d'établissements de soins de longue durée présentant un diagnostic de MA. Le pouvoir prédicteur de l'anosognosie sur le fardeau soignant a également été examiné. L'anosognosie des troubles de la construction (r = 0,40, p = 0,0164) et de l'initiation (r = 0,32, p = 0,052) était corrélée au fardeau soignant. Les professionnels se représentaient les résidents comme ayant une conscience altérée de leurs capacités, même en l'absence d'anosognosie. Les scores réels d'anosognosie ne prédisaient pas les estimations soignantes, hormis le score global sous forme de tendance (χ2 = 3,38, p = 0,066). Les soignants surestimaient pourtant les performances cognitives des résidents, telles que mesurées au moyen du protocole Misawareness (prédictions aidants/performances réelles : DC = 12,32, p < 0,0001).

Effects of multisite anodal transcranial direct current stimulation combined with cognitive stimulation in patients with Alzheimer's disease and its neurophysiological correlates: A double-blind randomized clinical trial

OBJECTIVES

We aimed to examine the effects of multisite anodal transcranial direct current stimulation (tDCS) combined with cognitive stimulation (CS) over 2 months on cognitive performance and brain activity, and the relationship between them, in patients with Alzheimer's disease (AD).

METHODS

Patients with AD were randomly assigned to an active tDCS+CS (n=18) or a sham tDCS+CS (n=18) group. Cognitive performance was assessed using the Alzheimer Disease Assessment Scale-cognitive subscale (ADAS-cog) and brain activity using EEG (spectral power and coherence analysis) before and after the intervention. Multisite anodal tDCS (2 mA, 30 min) was applied over six brain regions [left and right dorsolateral prefrontal cortex (F3 and F4), Broca's area (F5), Wernicke's area (CP5), left and right somatosensory association cortex (P3 and P4)] for 24 sessions (three times a week). Both groups performed CS during tDCS.

RESULTS

Anodal tDCS+CS delays cognitive decline (ADAS-cog change) to a greater extent than sham tDCS+CS (-3.4±1.1 vs. -1.7±0.4; p=.03). Bilateral EEG coherence at high and low frequencies was greater for the active tDCS+CS than sham+CS group for most electrode pairs assessed (p < .05). The post-intervention ADAS-cog change score was predictive for EEG coherence at different sites (R²=.59 to .68; p < .05) in the active but not in the sham tDCS+CS group.

CONCLUSION

Anodal tDCS+CS improved overall cognitive function and changed EEG brain activity compared to sham tDCS+CS. Changes in cognitive performance were associated with changes in EEG measures of brain activity. Anodal tDCS+CS appears to be a promising therapeutic strategy to modulate cortical activity and improve cognitive function in patients with AD.

Non-pharmacological Approaches to Apathy and Depression: A Scoping Review of Mild Cognitive Impairment and Dementia

Apathy and depression are frequently observed as behavioral and psychological symptoms of dementia, respectively, and are important for ensuring adequate care. This study aims to explore effective non-pharmacological interventions for apathy and depression with mild cognitive impairment (MCI) and dementia. Five search engines including PubMed, Scopus, CINAHL, PsycInfo, and Web of Science were used to extract relevant studies. Inclusion criteria were studies that involved participants who were diagnosed with MCI or dementia, included quantitative assessments of each symptom, and employed randomized controlled trials. Twenty studies were extracted, with interventions have been conducted in care facilities, the community, and hospitals. Participants in many studies had MCI or mild-to-moderate dementia but were not diagnosed with the subtypes of dementia. Few studies had set apathy and depression as the primary outcomes of non-pharmacological interventions. The findings suggested that emotional and stimulation-oriented approaches to apathy and depression would be useful for people with MCI or mild-to-moderate dementia. It would be helpful for therapists to assess the clinical features of the target symptoms for selecting suitable interventions. Additionally, increasing the number of randomized controlled trials focusing on apathy or depression as primary outcomes would offer a more definite conclusion for future systematic reviews.

The Effect of a Multimodal Occupational Therapy Program with Cognition-Oriented Approach on Cognitive Function and Activities of Daily Living in Patients with Alzheimer's Disease: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Non-pharmacological intervention, which includes a broad range of approaches, may be an alternative treatment for Alzheimer's disease (AD). Multimodal non-pharmacological intervention alleviates cognitive dysfunction and the impairment of activities of daily living (ADL) in AD patients. However, it is still unclear which combination of non-pharmacological interventions is preferred. We selected a non-pharmacological intervention combined with occupational therapy (OT). We investigated the effect of a multimodal OT program with cognition-oriented approach on cognitive dysfunction and impairments of ADL in patients with AD. Four electronic databases were searched from January 2000 to August 2020. The studies were assessed for heterogeneity, quality assessment, effect size and publication bias. A total of seven randomized controlled trials examining multimodal OT programs with cognition-oriented approach in AD patients were included in the meta-analysis. Compared with the control group, the multimodal OT program with cognition-oriented approach group was statistically beneficial for cognitive dysfunction (95% CI: 0.25-0.91). However, compared with the control group, the multimodal OT program with cognition-oriented approach group tended to be beneficial for basic ADL, and instrumental ADL. These results suggest that the multimodal OT program with cognition-oriented approach might be the optimal multimodal non-pharmacological intervention for improving cognitive dysfunction in AD patients.

Does awareness of condition help people with mild-to-moderate dementia to live well? Findings from the IDEAL programme

Background

People living with dementia vary in awareness of their abilities. We explored awareness of the condition and diagnosis in people with mild-to-moderate dementia, and how this relates to quality of life, well-being, life satisfaction, and caregiver stress.

Methods

This study was a cross-sectional exploratory analysis of data from the IDEAL cohort, which recruited people with dementia living at home and available caregivers from 29 research sites in Great Britain. Our study included 917 people with mild-to-moderate dementia and 755 carers. Low and high awareness groups were derived from self-reported responses to a dementia representation measure. Logistic regression was used to explore predictors of awareness of condition and diagnosis using demographic, cognitive, functional and psychological measures, and the relationship with quality of life, well-being and life satisfaction (‘living well’), and caregiver stress.

Results

There were 83 people with low awareness of their condition. The remaining 834 people showed some awareness and 103 of these had high awareness of their condition and diagnosis. Psychosocial factors were stronger predictors of awareness than cognitive and functional ability. Those with higher awareness reported lower mood, and lower scores on indices of living well as well as lower optimism, self-efficacy and self-esteem. Low awareness was more likely in those aged 80y and above, and living in more socially deprived areas. No relationship was seen between caregiver stress and awareness.

Conclusions

Awareness of the condition and diagnosis varies in people with mild-to-moderate dementia and is relevant to the capability to live well. Awareness should be considered in person-centered clinical care.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02468-4.

Measuring Awareness in People With Dementia: Results of a Systematic Scoping Review

BACKGROUND

Awareness of the diagnosis or related changes in functioning varies in people with dementia (PwD), with implications for the well-being of PwD and their carers. Measuring awareness in a clinical setting could facilitate tailored support and optimize involvement in personal health and care decisions. This scoping review aimed to identify validated methods of assessing awareness in dementia and appraise their clinical utility.

METHOD

A systematic search was conducted of English-language publications that measured awareness in PwD, in 6 electronic databases. Search terms included dement*, Alzheimer*, Pick disease, and awareness, unawareness, anosognosia, insight, denial, metacognit*, or discrepanc*.

RESULTS

We screened 30,634 articles, finding 345 articles that met our inclusion criteria. We identified 76 measures, most commonly using a discrepancy questionnaire comparing evaluations of function by PwD and an informant. There were 30 awareness measures developed and validated for use in dementia populations but few designed for general clinical use.

CONCLUSIONS

Although we found a range of clinical indications for measuring awareness, there were few studies investigating clinical applications and few tools designed for clinical purposes. Further investigation and development of a person-centered tool could facilitate health and care choices in mild-to-moderate dementia.

Comparative efficacy of interventions for reducing symptoms of depression in people with dementia: systematic review and network meta-analysis

OBJECTIVE

To describe the comparative efficacy of drug and non-drug interventions for reducing symptoms of depression in people with dementia who experience depression as a neuropsychiatric symptom of dementia or have a diagnosis of a major depressive disorder.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Medline, Embase, the Cochrane Library, CINAHL, PsycINFO, and grey literature between inception and 15 October 2020.

ELIGIBILITY CRITERIA FOR STUDY SELECTION

Randomised trials comparing drug or non-drug interventions with usual care or any other intervention targeting symptoms of depression in people with dementia.

MAIN OUTCOME MEASURES

Pairs of reviewers screened studies, abstracted aggregate level data, and appraised risk of bias with the Cochrane risk of bias tool, which facilitated the derivation of standardised mean differences and back transformed mean differences (on the Cornell scale for depression in dementia) from bayesian random effects network meta-analyses and pairwise meta-analyses.

RESULTS

Of 22 138 citations screened, 256 studies (28 483 people with dementia) were included. Missing data posed the greatest risk to review findings. In the network meta-analysis of studies including people with dementia without a diagnosis of a major depressive disorder who were experiencing symptoms of depression (213 studies; 25 177 people with dementia; between study variance 0.23), seven interventions were associated with a greater reduction in symptoms of depression compared with usual care: cognitive stimulation (mean difference -2.93, 95% credible interval -4.35 to -1.52), cognitive stimulation combined with a cholinesterase inhibitor (-11.39, -18.38 to -3.93), massage and touch therapy (-9.03, -12.28 to -5.88), multidisciplinary care (-1.98, -3.80 to -0.16), occupational therapy (-2.59, -4.70 to -0.40), exercise combined with social interaction and cognitive stimulation (-12.37, -19.01 to -5.36), and reminiscence therapy (-2.30, -3.68 to -0.93). Except for massage and touch therapy, cognitive stimulation combined with a cholinesterase inhibitor, and cognitive stimulation combined with exercise and social interaction, which were more efficacious than some drug interventions, no statistically significant difference was found in the comparative efficacy of drug and non-drug interventions for reducing symptoms of depression in people with dementia without a diagnosis of a major depressive disorder. Clinical and methodological heterogeneity precluded network meta-analysis of studies comparing the efficacy of interventions specifically for reducing symptoms of depression in people with dementia and a major depressive disorder (22 studies; 1829 patients).

CONCLUSIONS

In this systematic review, non-drug interventions were found to be more efficacious than drug interventions for reducing symptoms of depression in people with dementia without a major depressive disorder.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017050130.

The Effect of Cognitive Training in a Day Care Center in Patients with Early Alzheimer's Disease Dementia: A Retrospective Study

OBJECTIVE

This study aimed to evaluate the effect of cognitive training programs on the progression of dementia in patients with early stage Alzheimer's disease dementia (ADD) at the day care center.

METHODS

From January 2015 to December 2018, a total of 119 patients with early ADD were evaluated. All subjects were classified into two groups according to participate in cognitive training program in addition to usual standard clinical care. Changes in scores for minimental status examination-dementia screening (MMSE-DS) and clinical dementia rating-sum of boxes (CDR-SOB) during the 12 months were compared between two groups. Multivariable logistic regression analyses were performed.

RESULTS

As compared to case-subjects (n=43), the MMSE-DS and CDR-SOB scores were significantly worse at 12 months in the control-subjects (n=76). A statistically significant difference between the two groups was observed due to changes in MMSE-DS (p=0.012) and CDR-SOB (p<0.001) scores. Multivariable logistic regression analysis showed that the cognitive training program (odds ratio and 95% confidence interval: 0.225, 0.070-0.725) was independently associated with less progression of ADD.

CONCLUSION

The cognitive training program was associated with benefits in maintaining cognitive function for patients with earlystage ADD that were receiving medical treatment.

Comparison of mortality rate in older adults with and without functional awareness: the Neurological Disorders in Central Spain (NEDICES) population-based study

OBJECTIVES

The main aim of the study was to compare the rates of mortality in older adults with and without functional unawareness (FU). We also tested a possible interaction effect between levels of awareness and education, as a single cognitive reserve proxy, on mortality.

STUDY DESIGN

The study design is a longitudinal population-based cohort study.

METHODS

The Neurological Disorders in Central Spain is epidemiological study to detect main age-associated conditions in people aged 65 years and older. Participants were collected from updated population-based registers of residents in three areas of central Spain. Awareness of functional limitations was established in accordance with the discrepancy between two sources of information on functional impairments: reliable informants versus the participants themselves. Three mutually exclusive groups were formed, namely, Functional Limitation Complaints (FCs), FU, and Functional Awareness (FA). Cox's regression models, adjusted by different covariates, were used to calculate the risk of mortality for each group at 5-year follow-up (vs. reference group without limitations).

RESULTS

Of 1818 selected individuals, 229 (12.5%) showed FA, 254 (13.9%) showed FC, and 96 (5%) were classified as FU. All these groups showed an increased risk of mortality at 5-year follow-up [adjusted hazard ratio (HR) for FC < FU < FA]. However, the association of FU with mortality remained significant only for highly educated individuals.

CONCLUSIONS

Functional impairment was associated with increased mortality rates, regardless of the presence of unawareness. This study extends the role of education in modulating the symptoms and prognosis of individuals at very mild or preclinical dementia stages.

Outcomes tested in non-pharmacological interventions in mild cognitive impairment and mild dementia: a scoping review

OBJECTIVES

Non-pharmacological treatments are an important aspect of dementia care. A wide range of interventions have been trialled for mild dementia and mild cognitive impairment (MCI). However, the variety of outcome measures used in these trials makes it difficult to make meaningful comparisons. The objective of this study is to map trends in which outcome measures are used in trials of non-pharmacological treatments in MCI and mild dementia.

DESIGN

Scoping review.

DATA SOURCES

EMBASE, PsychINFO, Medline and the Cochrane Register of Controlled Trials were searched from inception until February 2018. An additional search was conducted in April 2019 ELIGIBILITY: We included randomised controlled trials (RCTs) testing non-pharmacological interventions for people diagnosed with MCI or mild dementia. Studies were restricted to full RCTs; observational, feasibility and pilot studies were not included.

CHARTING METHODS

All outcome measures used by included studies were extracted and grouped thematically. Trends in the types of outcome measures used were explored by type of intervention, country and year of publication.

RESULTS

91 studies were included in this review. We extracted 358 individual outcome measures, of which 78 (22%) were used more than once. Cognitive measures were the most frequently used, with the Mini-Mental State Examination being the most popular.

CONCLUSIONS

Our findings highlight an inconsistency in the use of outcome measures. Cognition has been prioritised over other domains, despite previous research highlighting the importance of quality of life and caregiver measures. To ensure a robust evidence base, more research is needed to highlight which outcome measures should be used over others.

PROSPERO REGISTRATION NUMBER

CRD42018102649.

Effects of nonpharmacological interventions on functioning of people living with dementia at home: A systematic review of randomised controlled trials

OBJECTIVE

Slowing functional decline could enable people living with dementia to live for longer and more independently in their own homes. We aimed to update previous syntheses examining the effectiveness of nonpharmacological interventions in reducing functional decline (activities of daily living, activity-specific physical functioning, or function-specific goal attainment) in people living in their own homes with dementia.

METHODS

We systematically searched electronic databases from January 2012 to May 2018; two researchers independently rated risk of bias of randomised controlled trials (RCTs) fitting predetermined inclusion criteria using a checklist; we narratively synthesised findings, prioritising studies judged to have a lower risk of bias.

RESULTS

Twenty-nine papers (describing 26 RCTs) met eligibility criteria, of which we judged 13 RCTs to have a lower risk of bias. Study interventions were evaluated in four groups: physical exercise, occupational, multicomponent, and cognition-oriented interventions. Four out of 13 RCTs reported functional ability as a primary outcome. In studies judged to have a lower risk of bias, in-home tailored exercise, individualised cognitive rehabilitation, and in-home activities-focussed occupational therapy significantly reduced functional decline relative to control groups in individual studies. There was consistent evidence from studies at low risk of bias that group-based exercise and reminiscence therapies were ineffective at reducing functional decline.

CONCLUSION

We found no replicated evidence of intervention effectiveness in decreasing functional decline. Interventions associated with slower functional decline in individual trials have been individually delivered and tailored to the needs of the person with dementia. This is consistent with previous findings. Future intervention trials should prioritise these approaches.

Evaluation of the South Korean national long-term care insurance-funded cognitive function training programme for older people with mild dementia

OBJECTIVES

despite the extensive literature on the effectiveness of cognitive training, its effectiveness has not been demonstrated within a population-based long-term care system. To provide cognitive training services to older people with mild dementia, Korea introduced a special dementia rating, as a long-term care grades, in the national long-term care insurance in July 2014. These services are only offered to those with the special dementia rating. This study evaluated the national long-term care insurance-funded cognitive function training programme for older people with mild dementia.

METHODS

data were derived from the Korean National Health Insurance Elderly Cohort database between 2008 and 2015. We compared changes in function between the intervention (n = 352) and control (n = 1952) groups before (2014) and after (2015) introduction of the cognitive function training programme. Difference-in-differences analysis was performed, to compare changes in each score between the intervention and control groups before and after introduction of the cognitive function training programme.

RESULTS

introduction of the cognitive function training programme was associated with significantly less cognitive function decline in the intervention group than in the control groups (β = -3.39; standard errors [SE] = 1.14; P = 0.003). A subgroup analysis revealed that this effect increased in subjects in the youngest group, low income bracket, who had a primary caregiver, who were supported in multiple activities of daily living by the primary caregiver, or who were not living alone.

CONCLUSIONS

introduction of the cognitive function training programme was associated with positive effects on cognitive function.

Rehabilitation for People Living with Dementia: A Scoping Review of Processes and Outcomes

Objectives

The aim of this scoping review was to map intervention studies of rehabilitation for people living with dementia regarding processes and outcomes, with a particular focus on whether the intervention is person-centred, home-based, or organised adopting a multidisciplinary approach and measures outcomes relating to everyday functioning and well-being.

Methods

A systematic search of electronic databases was conducted in PubMed, CINAHL, PsycINFO, Embase, and Cochrane. Studies from 2005 to November 2018 were collected and screened for relevance and quality. Randomised control trials and prospective cohort trials reporting a statistically significant effect on one or more outcome measures were included. Included studies were mapped according to selected processes and outcome measures.

Results

Twenty-six intervention studies were included and mapped. Nineteen of the interventions were person-centred, nine were home-based, and 14 reported a multidisciplinary approach. Twelve of the interventions had activities of daily living as an outcome measure, and 14 had quality of life as an outcome measure.

Conclusion

Person-centredness appears in most rehabilitation interventions for people living with dementia. Other processes and outcomes are heterogeneously described in the research literature. Rehabilitation programmes can be home-based or take place at a centre. Although not exclusive, the organisation of rehabilitation can be multidisciplinary. Fewer than half of the intervention studies measure the impact on activities of daily living and quality of life. Future guidelines must take into account the weak evidence regarding these aspects.

Cognitive training for people with mild to moderate dementia

BACKGROUND

Cognitive impairment, a defining feature of dementia, plays an important role in the compromised functional independence that characterises the condition. Cognitive training (CT) is an approach that uses guided practice on structured tasks with the direct aim of improving or maintaining cognitive abilities.

OBJECTIVES

• To assess effects of CT on cognitive and non-cognitive outcomes for people with mild to moderate dementia and their caregivers.• To compare effects of CT with those of other non-pharmacological interventions, including cognitive stimulation or rehabilitation, for people with mild to moderate dementia and their caregivers.• To identify and explore factors related to intervention and trial design that may be associated with the efficacy of CT for people with mild to moderate dementia and their caregivers.

SEARCH METHODS

We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Group Specialised Register, on 5 July 2018. ALOIS contains records of clinical trials identified through monthly searches of several major healthcare databases and numerous trial registries and grey literature sources. In addition to this, we searched MEDLINE, Embase, PsycINFO, CINAHL, LILACS, Web of Science Core Collection, ClinicalTrials.gov, and the World Health Organization's trials portal, ICTRP, to ensure that searches were comprehensive and up-to-date.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that described interventions for people with mild to moderate dementia and compared CT versus a control or alternative intervention.

DATA COLLECTION AND ANALYSIS

We extracted relevant data from published manuscripts and through contact with trial authors if required. We assessed risk of bias using the Cochrane 'Risk of bias' tool. We divided comparison conditions into active or passive control conditions and alternative treatments. We used a large number of measures and data to evaluate 19 outcomes at end of treatment, as well as 16 outcomes at follow-up in the medium term; we pooled this information in meta-analyses. We calculated pooled estimates of treatment effect using a random-effects model, and we estimated statistical heterogeneity using a standard Chi² statistic. We graded the evidence using GradePro.

MAIN RESULTS

The 33 included trials were published between 1988 and 2018 and were conducted in 12 countries; most were unregistered, parallel-group, single-site RCTs, with samples ranging from 12 to 653 participants. Interventions were between two and 104 weeks long. We classified most experimental interventions as 'straight CT', but we classified some as 'augmented CT', and about two-thirds as multi-domain interventions. Researchers investigated 18 passive and 13 active control conditions, along with 15 alternative treatment conditions, including occupational therapy, mindfulness, reminiscence therapy, and others.The methodological quality of studies varied, but we rated nearly all studies as having high or unclear risk of selection bias due to lack of allocation concealment, and high or unclear risk of performance bias due to lack of blinding of participants and personnel.We used data from 32 studies in the meta-analysis of at least one outcome. Relative to a control condition, we found moderate-quality evidence showing a small to moderate effect of CT on our first primary outcome, composite measure of global cognition at end of treatment (standardised mean difference (SMD) 0.42, 95% confidence interval (CI) 0.23 to 0.62), and high-quality evidence showing a moderate effect on the secondary outcome of verbal semantic fluency (SMD 0.52, 95% CI 0.23 to 0.81) at end of treatment, with these gains retained in the medium term (3 to 12 months post treatment). In relation to many other outcomes, including our second primary outcome of clinical disease severity in the medium term, the quality of evidence was very low, so we were unable to determine whether CT was associated with any meaningful gains.When compared with an alternative treatment, we found that CT may have little to no effect on our first primary outcome of global cognition at end of treatment (SMD 0.21, 95% CI -0.23 to 0.64), but the quality of evidence was low. No evidence was available to assess our second primary outcome of clinical disease severity in the medium term. We found moderate-quality evidence showing that CT was associated with improved mood of the caregiver at end of treatment, but this was based on a single trial. The quality of evidence in relation to many other outcomes at end of treatment and in the medium term was too low for us to determine whether CT was associated with any gains, but we are moderately confident that CT did not lead to any gains in mood, behavioural and psychological symptoms, or capacity to perform activities of daily living.

AUTHORS' CONCLUSIONS

Relative to a control intervention, but not to a variety of alternative treatments, CT is probably associated with small to moderate positive effects on global cognition and verbal semantic fluency at end of treatment, and these benefits appear to be maintained in the medium term. Our certainty in relation to many of these findings is low or very low. Future studies should take stronger measures to mitigate well-established risks of bias, and should provide long-term follow-up to improve our understanding of the extent to which observed gains are retained. Future trials should also focus on direct comparison of CT versus alternative treatments rather than passive or active control conditions.

Neurostimulation Combined With Cognitive Intervention in Alzheimer's Disease (NeuroAD): Study Protocol of Double-Blind, Randomized, Factorial Clinical Trial

Despite advances in the treatment of Alzheimer’s disease (AD), there is currently no prospect of a cure, and evidence shows that multifactorial interventions can benefit patients. A promising therapeutic alternative is the use of transcranial direct current stimulation (tDCS) simultaneously with cognitive intervention. The combination of these non-pharmacological techniques is apparently a safe and accessible approach. This study protocol aims to compare the efficacy of tDCS and cognitive intervention in a double-blind, randomized and factorial clinical trial. One hundred participants diagnosed with mild-stage AD will be randomized to receive both tDCS and cognitive intervention, tDCS, cognitive intervention, or placebo. The treatment will last 8 weeks, with a 12-month follow-up. The primary outcome will be the improvement of global cognitive functions, evaluated by the AD Assessment Scale, cognitive subscale (ADAS-Cog). The secondary outcomes will include measures of functional, affective, and behavioral components, as well as a neurophysiological marker (Brain-derived neurotrophic factor, BDNF). This study will enable us to assess, both in the short and long term, whether tDCS is more effective than the placebo and to examine the effects of combined therapy (tDCS and cognitive intervention) and isolated treatments (tDCS vs. cognitive intervention) on patients with AD.

Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT02772185—May 5, 2016.

Antecedents and consequences of unawareness of memory impairment in dementia

OBJECTIVE

To assess the prevalence, antecedents, and consequences of unawareness of memory impairment in dementia.

METHOD

Persons (n = 1,862) from a geographically defined community without dementia at enrollment subsequently underwent clinical classification (248 with dementia, 611 with mild cognitive impairment, 1,003 with no cognitive impairment), memory testing, and self-appraisal of memory. Memory performance was regressed on self-appraised memory, and the residuals served as an index of memory awareness. After clinical classification, participants completed brief cognitive testing at 3-year intervals for up to 15 years.

RESULTS

When unawareness was defined as a score at or below thresholds ranging from the 15th to 25th percentiles, it was more common in dementia (67%-83%) and mild cognitive impairment (15%-33%) than in no cognitive impairment (2%-6%; all p < .001). A continuous measure of awareness (M = 0.00, SD = 0.61) was reduced by 0.37-unit in mild cognitive impairment (SE = 0.04, p < .001) and 1.04-unit in dementia (SE = 0.06), p < .001) compared with those without cognitive impairment, and these associations were weaker in Black persons than White persons (estimate for dementia by race = 0.37, SE = 0.12, p = .003; estimate for mild cognitive impairment by race = 0.30, SE = 0.08, p < .001). Higher premorbid neuroticism was associated with better memory awareness in dementia. Higher memory awareness was not related to mortality in mild cognitive impairment or dementia but had a marginal association with slower cognitive decline in mild cognitive impairment.

CONCLUSIONS

Unawareness of memory impairment is a common manifestation of dementia, particularly in White persons, but is not strongly related to adverse disease outcomes. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Training working memory updating in Parkinson's disease: A randomised controlled trial

Frontostriatal dysfunction in Parkinson's disease (PD) increases the risk for working memory (WM) impairment and depression, calling for counteractive measures. Computerised cognitive rehabilitation is a promising option, but targeted training protocols are lacking and lab-based training can be demanding due to the repeated visits. This study tested the feasibility and efficacy of home-based computerised training targeting mainly WM updating in PD. Fifty-two cognitively well-preserved PD patients were randomised to a WM training group and an active control group for five weeks of training (three 30-min sessions per week). WM training included three computerised adaptive WM tasks (two updating, one maintenance). The outcomes were examined pre- and post-training with trained and untrained WM tasks, tasks tapping other cognitive domains, and self-ratings of executive functioning and depression. Home-based training was feasible for the patients. The training group improved particularly on the updating training tasks, and showed posttest improvement on untrained WM tasks structurally similar to the trained ones. Moreover, their depression scores decreased compared to the controls. Our study indicates that patients with mild-to-moderate PD can self-administer home-based computerised WM training, and that they yield a similar transfer pattern to untrained WM tasks as has been observed in healthy older adults.

The Proactive Self in Space: How Egocentric and Allocentric Spatial Impairments Contribute to Anosognosia in Alzheimer's Disease

In addition to impairments in episodic and spatial memory, anosognosia (i.e., loss of awareness of the deficient aspect of own cognitive functioning) may be considered an important cognitive marker of Alzheimer's disease (AD). However, although a growing body of interesting models have been proposed to explain this early symptom, what is still missing is a unifying framework of all the characteristic signs occurring in patients with AD that may guide the search for its causal neuropathological process and, ultimately, the etiological process. This contribution will first show how anosognosia may be related to the above-mentioned episodic and spatial memory impairment through a unifying framework of all these characteristic signs, i.e., the continuous interaction between different spatial representations. Second, we hypothesize that a break in the interaction between different spatial representations, as we suggest occurs in AD, may contribute significantly both to the early impairments in spatial and episodic memory, and to a deficient self-awareness since it may interfere with the capacity of the brain to detect predictive errors.

Cognitive Training Interventions for Patients with Alzheimer's Disease: A Systematic Review

BACKGROUND

Cognitive training (CT) refers to guided cognitive exercises designed to improve specific cognitive functions, as well as enhance performance in untrained cognitive tasks. Positive effects of CT on cognitive functions in healthy elderly people and persons with mild cognitive impairment have been reported, but data regarding the effects of CT in patients with dementia is unclear.

OBJECTIVE

We systematically reviewed the current evidence from randomized controlled trials (RCTs) to find out if CT improves or stabilizes cognition and/or everyday functioning in patients with mild and moderate Alzheimer's disease.

RESULTS

Altogether, 31 RCTs with CT as either the primary intervention or part of a broader cognitive or multi-component intervention were found. A positive effect was reported in 24 trials, mainly on global cognition and training-specific tasks, particularly when more intensive or more specific CT programs were used. Little evidence of improved everyday functioning was found.

CONCLUSIONS

Despite some positive findings, the inaccurate definitions of CT, inadequate sample sizes, unclear randomization methods, incomplete datasets at follow-up and multiple testing may have inflated the results in many trials. Future high quality RCTs with appropriate classification and specification of cognitive interventions are necessary to confirm CT as an effective treatment option in Alzheimer's disease.

Interaction Effect of Awareness and Educational Attainment on the Benefits of Multicomponent Intervention for Persons with Mild Alzheimer's Disease

OBJECTIVE

The study investigated the effect of education on cognitive outcome following a multicomponent intervention program (MIP) for people with Alzheimer's disease (AD), also exploring the additional effect of level of awareness.

METHODS

Fifty-five participants with mild AD were randomized to an MIP (intervention group; IG) or a waiting-list (WL) group. They were further stratified into 4 groups by educational attainment (high vs. low) and level of awareness (aware [IGU-] vs. unaware [IGU+]). MIP efficacy in the different groups was measured using the mean change scores (MCSs) in the Cognitive subscale of Alzheimer's disease Assessment Scale, with pre- and post-treatment testing.

RESULTS

A negative correlation was found between educational level and the MCS in the IG, whereas the correlation in the WL group was positive. Moreover, an interaction effect emerged between education and awareness. Here, in the group of aware individuals, those with high education benefited more from the intervention than those with low education. This difference was not observed in the unawareness group.

CONCLUSION

Higher education may diminish the progression of cognitive decline after MIP, but this potentially depends on the level of awareness.

Influence of Educational Attainment on Cognition-Based Intervention Programs for Persons with Mild Alzheimer's Disease

OBJECTIVES

This research retrospectively analyzed the effect of education on cognitive interventions carried out in patients with mild Alzheimer's disease (AD).

METHODS

The total sample consisted of 75 patients with mild AD receiving treatment with cholinesterase inhibitors. The participants were divided into two groups: cognitive intervention (IG; n=45) and waiting list (WLG; n=30). Patients in the IG received either the Big Brain Academy (n=15) or the Integrated Psychostimulation Program (n=30) during 12 weeks. The influence of education on intervention effect was analyzed comparing mean change scores of the two study groups in the cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-cog), stratified by educational level. The potential effect of age, sex, cognitive status, and type of intervention was examined using post hoc stratification analyses.

RESULTS

Higher education was associated with faster cognitive decline in the WLG (effect size=0.51; p<.01). However, cognitive evolution was not influenced by education in the IG (effect size=0.12; p=.42).

CONCLUSIONS

Our results suggest that cognitive intervention might delay accelerated cognitive decline in higher educated individuals with mild AD.