Executive functioning in early stage Parkinson's disease

Background: Cognitive decline is commonly reported in Parkinson’s disease (PD), with some deficits evident even at the onset of PD. Executive functions (EF) are extensively studied in PD and emerge as the domain involving the most profound deficits. Nevertheless, there are some inconsistencies in the literature with regard to the exact pattern of executive deficits and their impact on everyday life in PD. The aim of the literature review presented in this thesis was to synthesise and clarify existing research evidence on EF in early stage PD, and to explore what are the possible factors affecting the consistency of research findings. The empirical studies had three distinct aims: to clarify the pattern of EF deficits in PD; to determine how accurately PwPD appraise potential EF-related difficulties; and to identify how executive deficits impact on people with PD (PwPD) and their families. Method: Studies of EF in PD were systematically reviewed and the findings were synthesised in a series of meta-analyses. Three empirical studies drew on cross-sectional data collected from PwPD and their caregivers, and from healthy older controls. Sixty-five PwPD in mild to moderate stages of PD completed an assessment of EF, awareness, quality of life, and health status, and 43 healthy older controls completed assessment of EF and awareness. Fifty caregivers of PwPD rated the EF of the PwPD and their own burden associated with caring for a PwPD. A sub-group of 34 PwPD, identified as having potential EF deficits, completed a more extensive neuropsychological assessment of executive abilities. Results: The systematic review included 33 studies of EF in early stage PD, and metaanalysis of data from 5 commonly-used tests of EF revealed consistent evidence for executive deficits. The review suggested that the consistency of the research evidence may be improved by more precision in defining EF and more careful selection and interpretation of EF measures. A data-driven analysis examining the pattern of EF impairment distinguished differences between two groups of standard tests of EF, with attentional control tests more frequently compromised than abstract thinking in early stage PD. PwPD were found to be accurate when making general evaluative judgments about their own functioning, but in specific tasks PwPD with executive deficits overestimated their performance in comparison to PwPD without EF deficits and healthy controls. EF-related behavioural difficulties were shown to impact on subjective quality of life in PwPD and on burden in their caregivers. Conclusions: The results of this thesis suggest that EF-related difficulties are frequently present in early stage PD, with attentional control aspects of EF particularly affected, that it may be difficult for PwPD to accurately appraise their own ability to carry out specific activities, and that EF-related difficulties have a significant impact on quality of life in PwPD and their families. A thorough understanding of executive deficits in PD is important in the provision of adequate person-centred care for PwPD and their family members, and could help to inform the development of PD-specific rehabilitative interventions aimed at reducing activity limitation and restrictions on social participation and supporting PwPD in living well with the condition

What are subjective cognitive difficulties and do they matter?

Background subjective cognitive difficulties (SCD) have been associated with a higher risk of developing dementia. However, there is large variation in the way SCD are assessed and in their associations with cognitive functioning. Objective to compare the agreement of different SCD measures in identifying people with SCD and to investigate whether SCD are more strongly associated with cognitive functioning, mood, subjective age or background variables. Methods this cross-sectional study included 206 community-dwelling people aged ≥65. SCD were assessed with individual domain specific questions and a multiple-item scaled measure. Performance on tests of memory, attention, and executive function, and ratings of mood, subjective age and demographic information were recorded. Results there was some classification overlap between the five measures of SCD, however of the 64 people identified as having SCD, only one person appeared in all five measures of SCD and 34 people were classified by one measure only. There were limited associations between SCD and objective cognition, with more consistent associations with mood and subjective age. Conclusions the conflicting evidence regarding whether SCD are related to objective cognition and future risk of dementia may be due to different measures of SCD being employed. Careful consideration and standardisation is recommended regarding the cognitive domains and the reference groups for comparison, the response structure and the classification criteria. Longitudinal studies of SCD that include these considerations are needed to clarify the conceptual utility of SCD

Implementation processes in a cognitive rehabilitation intervention for people with dementia: a complexity-informed qualitative analysis

© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY. Published by BMJ. https://creativecommons.org/licenses/by/4.0/Objectives: Healthcare is often delivered through complex interventions. Understanding how to implement these successfully is important for optimising services. This article demonstrates how the complexity theory concept of ‘self-organisation’ can inform implementation, drawing on a process evaluation within a randomised controlled trial of the GREAT (Goal-oriented cognitive Rehabilitation in Early-stage Alzheimer’s and related dementias: a multi-centre single-blind randomised controlled Trial) intervention which compared a cognitive rehabilitation intervention for people with dementia with usual treatment. Design: A process evaluation examined experiences of GREAT therapists and participants receiving the intervention, through thematic analysis of a focus group with therapists and interviews with participants and their carers. Therapy records of participants receiving the intervention were also analysed using adapted framework analysis. Analysis adopted a critical realist perspective and a deductive-inductive approach to identify patterns in how the intervention operated. Setting: The GREAT intervention was delivered through home visits by therapists, in eight regions in the UK. Participants: Six therapists took part in a focus group, interviews were conducted with 25 participants and 26 carers, and therapy logs for 50 participants were analysed. Intervention: A 16-week cognitive rehabilitation programme for people with mild-to-moderate dementia. Results: ‘Self-organisation’ of the intervention occurred through adaptations made by therapists. Adaptations included simplifying the intervention for people with greater cognitive impairment, and extending it to meet additional needs. Relational work by therapists produced an emergent outcome of ‘social support’. Self-organised aspects of the intervention were less visible than formal components, but were important aspects of how it operated during the trial. This understanding can help to inform future implementation. Conclusions: Researchers are increasingly adopting complexity theory to understand interventions. This study extends the application of complexity theory by demonstrating how ‘self-organisation’ was a useful concept for understanding aspects of the intervention that would have been missed by focusing on formal intervention components. Analysis of self-organisation could enhance future process evaluations and implementation studies. Trial registration number: ISRCTN21027481.Peer reviewedFinal Published versio

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

This is the author accepted manuscript. The final version is available from NIHR Journals Library via the DOI in this record.The published version is available in ORE at http://hdl.handle.net/10871/36867This study was funded by the National Institute for Health Research (NIHR) Health Technology Assessment (HTA) programme; PI Professor L Clare; HTA reference 11/15/04

Cognitive rehabilitation, self-management, psychotherapeutic and caregiver support interventions in progressive neurodegenerative conditions: a scoping review

BACKGROUND: Despite their potentially significant impact, cognitive disability may be overlooked in a number of progressive neurodegenerative conditions, as other difficulties dominate the clinical picture. OBJECTIVE: We examined the extent, nature and range of the research evidence relating to cognitive rehabilitation, self-management, psychotherapeutic and caregiver support interventions in Parkinsonian disorders, multiple sclerosis (MS), frontotemporal dementias (FTD), motor neuron disease and Huntington’s disease. METHODS: Scoping review based on searches of MEDLINE and CINAHL up to 15 March 2016. RESULTS: We included 140 eligible papers. Over half of the studies, and almost all the randomised controlled trials, related to MS, while a number of single case studies described interventions for people with FTD. CR interventions addressed functional ability, communication and interaction, behaviour or memory. The majority of psychotherapy interventions involved cognitive behavioural therapy for depression or anxiety. Self-management interventions were mainly available for people with MS. There were few reports of interventions specific to caregivers. Numerous methodological challenges were identified. CONCLUSIONS: The limited range of studies for all conditions except MS suggests a need firstly to synthesise systematically the available evidence across conditions and secondly to develop well-designed studies to provide evidence about the effectiveness of CR and other psychological interventions

Executive functioning in early stage Parkinson's disease

Background: Cognitive decline is commonly reported in Parkinson’s disease (PD), with some deficits evident even at the onset of PD. Executive functions (EF) are extensively studied in PD and emerge as the domain involving the most profound deficits. Nevertheless, there are some inconsistencies in the literature with regard to the exact pattern of executive deficits and their impact on everyday life in PD. The aim of the literature review presented in this thesis was to synthesise and clarify existing research evidence on EF in early stage PD, and to explore what are the possible factors affecting the consistency of research findings. The empirical studies had three distinct aims: to clarify the pattern of EF deficits in PD; to determine how accurately PwPD appraise potential EF-related difficulties; and to identify how executive deficits impact on people with PD (PwPD) and their families. Method: Studies of EF in PD were systematically reviewed and the findings were synthesised in a series of meta-analyses. Three empirical studies drew on cross-sectional data collected from PwPD and their caregivers, and from healthy older controls. Sixty-five PwPD in mild to moderate stages of PD completed an assessment of EF, awareness, quality of life, and health status, and 43 healthy older controls completed assessment of EF and awareness. Fifty caregivers of PwPD rated the EF of the PwPD and their own burden associated with caring for a PwPD. A sub-group of 34 PwPD, identified as having potential EF deficits, completed a more extensive neuropsychological assessment of executive abilities. Results: The systematic review included 33 studies of EF in early stage PD, and metaanalysis of data from 5 commonly-used tests of EF revealed consistent evidence for executive deficits. The review suggested that the consistency of the research evidence may be improved by more precision in defining EF and more careful selection and interpretation of EF measures. A data-driven analysis examining the pattern of EF impairment distinguished differences between two groups of standard tests of EF, with attentional control tests more frequently compromised than abstract thinking in early stage PD. PwPD were found to be accurate when making general evaluative judgments about their own functioning, but in specific tasks PwPD with executive deficits overestimated their performance in comparison to PwPD without EF deficits and healthy controls. EF-related behavioural difficulties were shown to impact on subjective quality of life in PwPD and on burden in their caregivers. Conclusions: The results of this thesis suggest that EF-related difficulties are frequently present in early stage PD, with attentional control aspects of EF particularly affected, that it may be difficult for PwPD to accurately appraise their own ability to carry out specific activities, and that EF-related difficulties have a significant impact on quality of life in PwPD and their families. A thorough understanding of executive deficits in PD is important in the provision of adequate person-centred care for PwPD and their family members, and could help to inform the development of PD-specific rehabilitative interventions aimed at reducing activity limitation and restrictions on social participation and supporting PwPD in living well with the condition

Implementing a home-based personalised cognitive rehabilitation intervention for people with mild-to-moderate dementia: GREAT into Practice

Evidence-based rehabilitative interventions, if widely implemented, could equip people with dementia and their families to manage life with the condition and reduce the need for health and care services. The aim of this translational study, building on evidence from the GREAT randomised controlled trial, was to develop a foundation for implementing the GREAT Cognitive Rehabilitation intervention in community-based services for people with mild-to-moderate dementia. Methods Key elements of the implementation strategy were identifying and supporting managerial and clinical leadership, conducting collaborative planning and target-setting, training and supporting practitioners, and providing external facilitation. We developed implementation plans with, and trained staff in, 14 organisations. We subsequently worked closely with 11 of these, 10 National Health Service organisations and one private home care provider, to support practitioners to deliver GREAT Cognitive Rehabilitation over a 12-month period. Outcome evaluation examined the perspectives of local steering group members, practitioners and service users, and the reach, effectiveness and cost of the intervention. Results Implementation was disrupted by the COVID-19 pandemic, but six organisations completed at least six months of intervention delivery. Forty-one practitioners, mainly occupational therapists, provided the intervention, and 54 people with dementia completed a course of GREAT Cognitive Rehabilitation. Goal attainment by people with dementia exceeded levels of improvement seen in the original trial. People with dementia, carers, practitioners and steering group members all evaluated the intervention positively, and economic analysis indicated that the intervention could be provided at modest cost. However, we identified a range of mainly organisational barriers that impeded implementation and limited the potential for sustainability. Conclusions GREAT Cognitive Rehabilitation benefits people with dementia, can be delivered effectively at modest cost in routine services, and is viewed positively by people with dementia, family carers and practitioners. To fully realise these benefits and achieve widespread and sustainable implementation, however, requires sufficient resources and a reorientation of service priorities towards preventive and rehabilitative approache