ETNA3, a clinical randomized study assessing three cognitive-oriented therapies in dementia: rationale and general design

Cognitive rehabilitation for people with mild to moderate dementia

BACKGROUND

Cognitive impairments affect functional ability in people with dementia. Cognitive rehabilitation (CR) is a personalised, solution-focused approach that aims to enable people with mild-to-moderate dementia to manage everyday activities and maintain as much independence as possible.

OBJECTIVES

To evaluate the effects of CR on everyday functioning and other outcomes for people with mild-to-moderate dementia, and on outcomes for care partners. To identify and explore factors that may be associated with the efficacy of CR.

SEARCH METHODS

We searched the Cochrane Dementia and Cognitive Improvement Group Specialised Register, which contains records from MEDLINE, EMBASE, CINAHL, PsycINFO, LILACS, and other clinical trial databases, and grey literature sources. The most recent search was completed on 19 October 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing CR with control conditions and reporting relevant outcomes for the person with dementia and/or the care partner.

DATA COLLECTION AND ANALYSIS

We extracted relevant data from published manuscripts and contacted trial authors if necessary. Within each of the comparisons, we pooled data for each outcome of interest and conducted inverse-variance, random-effects meta-analyses. We evaluated the certainty of the evidence using GRADEpro GDT.

MAIN RESULTS

We identified six eligible RCTs published in English between 2010 and 2022, which together included 1702 participants. The mean age of participants ranged from 76 to 80 and the proportion of male participants was between 29.4% and 79.3%. Most participants, in the studies where the type of dementia was reported, had a diagnosis of Alzheimer's disease (AD; n = 1002, 58.9% of the whole sample, 81.2% of the participants for whom the specific diagnosis was reported). Risk of bias in the individual studies was relatively low. The exception was a high risk of bias in relation to blinding of participants and practitioners, which is not usually feasible with psychosocial interventions.  Our primary outcome of everyday functioning was operationalised in the included studies as goal attainment in relation to activities targeted in the intervention. For our main comparison of CR with usual care, we pooled data for goal attainment evaluated from three perspectives (self-rating of performance, informant rating of performance, and self-rating of satisfaction with performance) at end of treatment and at medium-term follow-up (3 to 12 months). We could also pool data at these time points for 20 and 19 secondary outcomes respectively. The review findings were strongly driven by one large, high-quality RCT.  We found high-certainty evidence of large positive effects of CR on all three primary outcome perspectives at the end of treatment: participant self-ratings of goal attainment (standardised mean difference (SMD) 1.46, 95% confidence interval (CI) 1.26 to 1.66; I2 = 0%; 3 RCTs, 501 participants), informant ratings of goal attainment (SMD 1.61, 95% CI 1.01 to 2.21; I2 = 41%; 3 RCTs, 476 participants), and self-ratings of satisfaction with goal attainment (SMD 1.31, 95% CI 1.09 to 1.54; I2 = 5%; 3 RCTs, 501 participants), relative to an inactive control condition. At medium-term follow-up, we found high-certainty evidence showing a large positive effect of CR on all three primary outcome perspectives: participant self-ratings of goal attainment (SMD 1.46, 95% CI 1.25 to 1.68; I2 = 0%; 2 RCTs, 432 participants), informant ratings of goal attainment (SMD 1.25, 95% CI 0.78 to 1.72; I2 = 29%; 3 RCTs, 446 participants), and self-ratings of satisfaction with goal attainment (SMD 1.19, 95% CI 0.73 to 1.66; I2 = 28%; 2 RCTs, 432 participants), relative to an inactive control condition. For participants at the end of treatment we found high-certainty evidence showing a small positive effect of CR on self-efficacy (2 RCTs, 456 participants) and immediate recall (2 RCTs, 459 participants). For participants at medium-term follow-up we found moderate-certainty evidence showing a small positive effect of CR on auditory selective attention (2 RCTs, 386 participants), and a small negative effect on general functional ability (3 RCTs, 673 participants), and we found low-certainty evidence showing a small positive effect on sustained attention (2 RCTs, 413 participants), and a small negative effect on memory (2 RCTs, 51 participants) and anxiety (3 RCTs, 455 participants).  We found moderate- and low-certainty evidence indicating that at the end of treatment CR had negligible effects on participant anxiety, quality of life, sustained attention, memory, delayed recall, and general functional ability, and at medium-term follow-up on participant self-efficacy, depression, quality of life, immediate recall, and verbal fluency. For care partners at the end of treatment we found low-certainty evidence showing a small positive effect on environmental aspects of quality of life (3 RCTs, 465 care partners), and small negative effects of CR on level of depression (2 RCTs, 32 care partners) and on psychological wellbeing (2 RCTs, 388 care partners).  For care partners at medium-term follow-up we found high-certainty evidence showing a small positive effect of CR on social aspects of quality of life (3 RCTs, 436 care partners) and moderate-certainty evidence showing a small positive effect on psychological aspects of quality of life (3 RCTs, 437 care partners). We found moderate- and low-certainty evidence at the end of treatment that CR had negligible effects on care partners' physical health, psychological and social aspects of quality of life, and stress, and at medium-term follow-up for the physical health aspect of care partners' quality of life and psychological wellbeing.

AUTHORS' CONCLUSIONS

CR is helpful in enabling people with mild or moderate dementia to improve their ability to manage the everyday activities targeted in the intervention. Confidence in these findings could be strengthened if more high-quality studies contributed to the observed effects. The available evidence suggests that CR can form a valuable part of a clinical toolkit to assist people with dementia in overcoming some of the everyday barriers imposed by cognitive and functional difficulties. Future research, including process evaluation studies, could help identify avenues to maximise CR effects and achieve wider impacts on functional ability and wellbeing.

Goal-oriented cognitive rehabilitation for early-stage Alzheimer's and related dementias: the GREAT RCT

BACKGROUND

Cognitive rehabilitation (CR) is an individualised, person-centred intervention for people with mild to moderate dementia that addresses the impact of cognitive impairment on everyday functioning.

OBJECTIVES

To determine whether or not CR is a clinically effective and cost-effective intervention for people with mild to moderate Alzheimer's disease or vascular or mixed dementia, and their carers.

DESIGN

This multicentre randomised controlled trial compared CR with treatment as usual (TAU). Following a baseline assessment and goal-setting to identify areas of everyday functioning that could be improved or better managed, participants were randomised (1 : 1) via secure web access to an independent randomisation centre to receive either TAU or CR and followed up at 3 and 9 months post randomisation.

SETTING

Community.

PARTICIPANTS

Participants had an International Classification of Diseases, Tenth Edition, diagnosis of Alzheimer's disease or vascular or mixed dementia, had mild to moderate cognitive impairment (Mini Mental State Examination score of ≥ 18 points), were stable on medication if prescribed, and had a family carer who was willing to contribute. The exclusion criteria were people with a history of brain injury or other neurological disorder and an inability to speak English. To achieve adequate power, we needed 350 people to complete the trial, with 175 people in each trial arm.

INTERVENTION

Cognitive rehabilitation consisted of 10 therapy sessions over 3 months, followed by four maintenance sessions over 6 months, delivered in participants' homes. The therapists were nine occupational therapists and one nurse.

OUTCOME MEASURES

The primary outcome was self-reported goal attainment at 3 months. Goal attainment was also assessed at 9 months. Carers provided independent ratings of goal attainment at both time points. The secondary outcomes were participant quality of life, mood, self-efficacy and cognition, and carer stress, health status and quality of life. The assessments at 3 and 9 months were conducted by researchers who were blind to the participants' group allocation.

RESULTS

A total of 475 participants were randomised (CR arm, n = 239; TAU arm, n = 236), 427 participants (90%) completed the trial and 426 participants were analysed (CR arm, n = 208, TAU arm, n = 218). At 3 months, there were statistically significant large positive effects for participant-rated goal attainment [mean change in the CR arm: 2.57; mean change in the TAU arm: 0.86; Cohen'sd = 0.97, 95% confidence interval (CI) 0.75 to 1.19], corroborated by carer ratings (Cohen'sd = 1.11, 95% CI 0.89 to 1.34). These effects were maintained at 9 months for both the participant ratings (Cohen's d = 0.94, 95% CI 0.71 to 1.17) and the carer ratings (Cohen's d = 0.96, 95% CI 0.73 to 1.20). There were no significant differences in the secondary outcomes. In the cost-utility analyses, there was no evidence of cost-effectiveness in terms of gains in the quality-adjusted life-years (QALYs) of the person with dementia (measured using the DEMentia Quality Of Life questionnaire utility score) or the QALYs of the carer (measured using the EuroQol-5 Dimensions, three-level version) from either cost perspective. In the cost-effectiveness analyses, by reference to the primary outcome of participant-rated goal attainment, CR was cost-effective from both the health and social care perspective and the societal perspective at willingness-to-pay values of £2500 and above for improvement in the goal attainment measure. There was no evidence on the cost-effectiveness of the self-efficacy measure (the Generalized Self-Efficacy Scale) from either cost perspective.

LIMITATIONS

Possible limitations arose from the non-feasibility of using observational outcome measures, the lack of a general measure of functional ability and the exclusion of people without a carer or with rarer forms of dementia.

CONCLUSIONS

Cognitive rehabilitation is clinically effective in enabling people with early-stage dementia to improve their everyday functioning in relation to individual goals targeted in the therapy sessions.

FUTURE WORK

Next steps will focus on the implementation of CR into NHS and social care services and on extending the approach to people with rarer forms of dementia.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN21027481.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 10. See the NIHR Journals Library website for further project information.

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.