Cognitive rehabilitation for people with mild to moderate dementia.

Abstract

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.