Feasibility and acceptance of a nonpharmacological cognitive remediation intervention for patients with Parkinson disease

Cognitive Orientation to Daily Occupational Performance (CO-OP) in Parkinson's: Randomized Trial Findings

BACKGROUND

People with Parkinson's disease (PwPD) experience increasing disability due to progressive motor and non-motor symptoms. Comprehensive rehabilitation approaches are needed to maximize their daily functioning. CO-OP targets daily functioning and has established efficacy in populations with similar symptom profiles.

PURPOSE

To explore the potential of CO-OP for PwPD, a feasibility randomized controlled trial (RCT) was conducted.

METHODS

Consenting PwPD (n = 20) were recruited to a parallel group, assessor masked RCT. Following baseline assessment, participants were randomized to CO-OP (20 sessions:10-weeks) or a waitlist control (WLC; 0 sessions: 10 weeks). Goal attainment, functional and cognitive status, quality of life, self-efficacy, transfer, and maintenance were measured. Data were analyzed using descriptive statistics and multiple regression analysis.

RESULTS

Effort (M = 3.02/5) and enjoyment (M = 3.15/5) ratings; homework completion (M = 91%) and protocol adherence (M = 82%) indicate that CO-OP is feasible. CO-OP was superior to the WLC on Canadian Occupational Performance Measure (COPM) performance (p=<.001), COPM satisfaction (p=<.001), and Performance Quality Rating Scale (PQRS; p=<.001) but not the Goal Attainment Scale (GAS; p = .123).

CONCLUSIONS

Addressing a critical gap in Parkinson's disease management, findings suggest that CO-OP is implementable, feasible, and potentially beneficial for PwPD. Further research is warranted to further establish efficacy.

Efficacy of non-computerized cognitive rehabilitation in Parkinson's disease: A one year follow up study

In this study, we explored the effect of non-computerized cognitive rehabilitation in patients with Parkinson's disease in comparison with an intervention with elements of music therapy after the completion of a three-month program and one year after the end of the intervention. After the initial neuropsychological examination, the respondents were divided into two intervention groups. The experimental group (n = 26) underwent a twelve-week program of cognitive rehabilitation at a frequency of 60 minutes once a week. The control group (n = 27) underwent an intervention program with elements of music therapy at the same frequency. Respondents who underwent the cognitive rehabilitation program improved in the delayed recall from visual memory in the follow-up examination after the end of the cognitive intervention. One year after the end, the effect of cognitive rehabilitation persisted in delayed recall from visual memory and in executive mental flexibility. Cognitive rehabilitation is an effective approach to compensate for cognitive deficits in P D, but other approaches to cognitive stimulation may be equally effective.

Cognitive and executive impairments in Parkinson's disease psychosis: a Bayesian meta-analysis

BACKGROUND

Cognitive and executive deficits lead to worsening of quality of life and are a risk factor for developing dementia in people with Parkinson's disease (PD) with psychosis (PDP). However, which key cognitive domains are differentially affected in PDP compared with those without (PDnP), remains unclear. Here, we examined this using a Bayesian meta-analytical approach.

METHODS

Searches were conducted on PubMed, Web of Science, SCOPUS, Medline and PsycINFO. Hedges' g effect-size estimates were extracted from eligible studies as a measure of standard mean differences between PDP and PDnP participants. Meta-analyses were conducted separately for each cognitive domain and subdomain, we examined the effect of age, PD medications, PD duration and severity, depression and psychosis severity for all major domains with meta-regressions.

RESULTS

Effect-size estimates suggest worse performance on all major domains (k=105 studies) in PDP compared with PDnP participants, with global cognition (k=103 studies, g=-0.57), processing speed (k=29 studies, g=-0.58), executive functions (k=33, g=-0.56), episodic memory (k=30 studies, g=-0.58) and perception (k=34 studies, g=-0.55) as the most likely affected domains. Age, depression and PD duration had moderating effects on task-related performance across most of the major nine domains.

CONCLUSIONS

We report extensive deficits across nine domains as well as subdomains in PD psychosis, with global cognition, processing speed and executive functions as the most likely impaired. The presence of depression may influence task-related performance in PDP, alongside age and PD duration, but not dose of dopamine replacement treatments.

Efficacy and Feasibility of the CO-OP Approach in Parkinson's Disease: RCT Study Protocol

Background. Parkinson's disease (PD) leads to cognitive dysfunction which limits participation and occupational performance. Cognitive Orientation to Daily Occupational Performance (CO-OP) approach is effective in other adult neurological populations and warrants investigation in PD. Purpose. To describe a study protocol evaluating the preliminary efficacy and feasibility of CO-OP approach in PD. Method. A randomised controlled trial (RCT) with adults with PD was assigned to either: CO-OP training-intensive (CO-OP-I, 20 sessions) or waitlist control (WLC) followed by CO-OP-standard (CO-OP-S, 10 sessions). Outcomes. Occupational performance and satisfaction of adults with PD in chosen goals. Measures will be obtained at baseline, post-intervention, and 3-month follow-up. Implications. As the first RCT focused on CO-OP in PD, this trial will provide evidence for the potential of this approach in PD and lay the groundwork for future large-scale trials. Trial Registration. Australian New Zealand Clinical Trials registry, ACTRN12621001483842. Registered November 1, 2021; retrospectively registered 3 months after commencement.

Development and Co-design of NeuroOrb: A Novel “Serious Gaming” System Targeting Cognitive Impairment in Parkinson’s Disease

Whilst Parkinson’s disease (PD) is typically thought of as a motor disease, a significant number of individuals also experience cognitive impairment (CI), ranging from mild-CI to dementia. One technique that may prove effective in delaying the onset of CI in PD is cognitive training (CT); however, evidence to date is variable. This may be due to the implementation of CT in this population, with the motor impairments of PD potentially hampering the ability to use standard equipment, such as pen-and-paper or a computer mouse. This may, in turn, promote negative attitudes toward the CT paradigm, which may correlate with poorer outcomes. Consequently, optimizing a system for the delivery of CT in the PD population may improve the accessibility of and engagement with the CT paradigm, subsequently leading to better outcomes. To achieve this, the NeuroOrb Gaming System was designed, coupling a novel accessible controller, specifically developed for use with people with motor impairments, with a “Serious Games” software suite, custom-designed to target the cognitive domains typically affected in PD. The aim of the current study was to evaluate the usability of the NeuroOrb through a reiterative co-design process, in order to optimize the system for future use in clinical trials of CT in individuals with PD. Individuals with PD (n = 13; mean age = 68.15 years; mean disease duration = 8 years) were recruited from the community and participated in three co-design loops. After implementation of key stakeholder feedback to make significant modifications to the system, system usability was improved and participant attitudes toward the NeuroOrb were very positive. Taken together, this provides rationale for moving forward with a future clinical trial investigating the utility of the NeuroOrb as a tool to deliver CT in PD.

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.

Optimizing Cognitive Training for the Treatment of Cognitive Dysfunction in Parkinson's Disease: Current Limitations and Future Directions

Cognitive dysfunction, primarily involving impairments in executive function, visuospatial function and memory, is one of the most common non-motor symptoms of Parkinson’s disease (PD). Currently, the only pharmacological treatments available for the treatment of cognitive dysfunction in PD provide variable benefit, making the search for potential non-pharmacological therapies to improve cognitive function of significant interest. One such therapeutic strategy may be cognitive training (CT), which involves the repetition of standardized tasks with the aim of improving specific aspects of cognition. Several studies have examined the effects of CT in individuals with PD and have shown benefits in a variety of cognitive domains, but the widespread use of CT in these individuals may be limited by motor impairments and other concerns in study design. Here, we discuss the current state of the literature on the use of CT for PD and propose recommendations for future implementation. We also explore the potential use of more recent integrative, adaptive and assistive technologies, such as virtual reality, which may optimize the delivery of CT in PD.

Identifying key elements to assess patient's acceptability of neurorehabilitation in stroke survivors - a Delphi method

PURPOSE

Assessing patient acceptability of treatment is a clinical concern. No guidance exists to determine the best way to measure acceptability in stroke neurorehabilitation. This study identifies key elements to measure patient's acceptance of stroke neurorehabilitation by establishing expert consensus.

MATERIALS AND METHODS

A four-phase Delphi method with a three-round electronic-based survey was conducted. Experts were considered as stroke survivors or their caregivers and professionals in stroke neurorehabilitation. A twenty-five-item list was sourced from a literature review and discussion with a consumer panel (n = 22). In Round-1 (n = 118) and Round-2 (n = 80), experts ranked the items on a five-point scale. Consensus levels were validated by a Validation group in Round-3 (n = 50). Validity of the results was considered if consensus reached ≥70%, a non-bimodal pattern of response central tendency, SD in Round-2 was lower than that in Round-1, and the agreement scores of responses were similar between all rounds.

RESULTS

In Round-1&2 and Round-3, 77.5% (n = 62) and 74.0% (n = 37) respectively, of the respondents were professionals, 20.0% (n = 16, n = 10 respectively) were either stroke survivors or caregivers, and 2.57% (n = 2) and 6.0% (n = 3) respectively were professionals who themselves were stroke survivors or caregivers. The key elements which met all priori criteria are: Goal setting, Measurable progress, Functional improvement, Challenging, Motivation, Interactive, Communications with health professionals, Knowledge of treatment, and No risks.

CONCLUSIONS

Patient's acceptance is crucial to developing the appropriate neurorehabilitation interventions. Future clinical trials should consider these items when measuring patient's acceptance of stroke neurorehabilitation interventions during the development and evaluation phases.Implications for rehabilitationAssessing patient acceptability of treatment is a clinical concern in stroke neurorehabilitation.This study has identified nine key elements to assess patient acceptability of stroke neurorehabilitation. These key elements are: Goal setting, Measurable progress, Functional improvement, Challenging, Motivation, Interactive, Communications with health professionals, Knowledge of treatment, and No risks.Professionals should consider these elements when measuring patient's acceptance of an intervention during the development, piloting, evaluation, and implementation phases.These findings provide a framework in designing neurorehabilitation programs and clinical trials on acceptance of and adherence to treatment in stroke survivors.

Cognitive training interventions for dementia and mild cognitive impairment in Parkinson's disease

BACKGROUND

Approximately 60% to 80% of people with Parkinson's disease (PD) experience cognitive impairment that impacts on their quality of life. Cognitive decline is a core feature of the disease and can often present before the onset of motor symptoms. Cognitive training may be a useful non-pharmacological intervention that could help to maintain or improve cognition and quality of life for people with PD dementia (PDD) or PD-related mild cognitive impairment (PD-MCI).

OBJECTIVES

To determine whether cognitive training (targeting single or multiple domains) improves cognition in people with PDD and PD-MCI or other clearly defined forms of cognitive impairment in people with PD.

SEARCH METHODS

We searched the Cochrane Dementia and Cognitive Improvement Group Trials Register (8 August 2019), the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, and PsycINFO. We searched reference lists and trial registers, searched relevant reviews in the area and conference proceedings. We also contacted experts for clarifications on data and ongoing trials.

SELECTION CRITERIA

We included randomised controlled trials where the participants had PDD or PD-MCI, and where the intervention was intended to train general or specific areas of cognitive function, targeting either a single domain or multiple domains of cognition, and was compared to a control condition. Multicomponent interventions that also included motor or other elements were considered eligible.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles, abstracts, and full-text articles for inclusion in the review. Two review authors also independently undertook extraction of data and assessment of methodological quality. We used GRADE methods to assess the overall quality of the evidence.

MAIN RESULTS

Seven studies with a total of 225 participants met the inclusion criteria for this review. All seven studies compared the effects of a cognitive training intervention to a control intervention at the end of treatment periods lasting four to eight weeks. Six studies included people with PD living in the community. These six studies recruited people with single-domain (executive) or multiple-domain mild cognitive impairment in PD. Four of these studies identified participants with MCI using established diagnostic criteria, and two included both people with PD-MCI and people with PD who were not cognitively impaired. One study recruited people with a diagnosis of PD dementia who were living in long-term care settings. The cognitive training intervention in three studies targeted a single cognitive domain, whilst in four studies multiple domains of cognitive function were targeted. The comparison groups either received no intervention or took part in recreational activities (sports, music, arts), speech or language exercises, computerised motor therapy, or motor rehabilitation combined with recreational activity. We found no clear evidence that cognitive training improved global cognition. Although cognitive training was associated with higher scores on global cognition at the end of treatment, the result was imprecise and not statistically significant (6 trials, 178 participants, standardised mean difference (SMD) 0.28, 95% confidence interval (CI) -0.03 to 0.59; low-certainty evidence). There was no evidence of a difference at the end of treatment between cognitive training and control interventions on executive function (5 trials, 112 participants; SMD 0.10, 95% CI -0.28 to 0.48; low-certainty evidence) or visual processing (3 trials, 64 participants; SMD 0.30, 95% CI -0.21 to 0.81; low-certainty evidence). The evidence favoured the cognitive training group on attention (5 trials, 160 participants; SMD 0.36, 95% CI 0.03 to 0.68; low-certainty evidence) and verbal memory (5 trials, 160 participants; SMD 0.37, 95% CI 0.04 to 0.69; low-certainty evidence), but these effects were less certain in sensitivity analyses that excluded a study in which only a minority of the sample were cognitively impaired. There was no evidence of differences between treatment and control groups in activities of daily living (3 trials, 67 participants; SMD 0.03, 95% CI -0.47 to 0.53; low-certainty evidence) or quality of life (5 trials, 147 participants; SMD -0.01, 95% CI -0.35 to 0.33; low-certainty evidence). There was very little information on adverse events. We considered the certainty of the evidence for all outcomes to be low due to risk of bias in the included studies and imprecision of the results. We identified six ongoing trials recruiting participants with PD-MCI, but no ongoing trials of cognitive training for people with PDD.

AUTHORS' CONCLUSIONS

This review found no evidence that people with PD-MCI or PDD who receive cognitive training for four to eight weeks experience any important cognitive improvements at the end of training. However, this conclusion was based on a small number of studies with few participants, limitations of study design and execution, and imprecise results. There is a need for more robust, adequately powered studies of cognitive training before conclusions can be drawn about the effectiveness of cognitive training for people with PDD and PD-MCI. Studies should use formal criteria to diagnose cognitive impairments, and there is a particular need for more studies testing the efficacy of cognitive training in people with PDD.

Cognitive Rehabilitation in Parkinson's Disease: A Systematic Review

BACKGROUND

Cognitive impairments are the most common non-motor symptoms in Parkinson's disease (PD). These symptoms have a negative impact on patients' quality of life and daily living activities. This review will focus on published articles that investigated the efficacy of cognitive rehabilitation in PD.

OBJECTIVES

To review the existing literature on the efficacy of cognitive rehabilitation in PD and highlight the most effective form of intervention to prevent cognitive decline. This review will also point out any limitations and provide directions for future research.

METHODS

Published articles available in the Web of Science and PubMed databases up to November 2017 were reviewed for possible inclusion. We identified 15 articles that examined the effects of cognitive rehabilitation in PD and met inclusion criteria.

RESULTS

The main outcomes of this review indicated that, although previous studies used different cognitive rehabilitation methodologies, all studies reported cognitive improvements on at least one cognitive domain. Additionally, the most frequent cognitive domains showing improvements are executive functions and attention.

CONCLUSION

This review reports the outcomes of studies that examined the effectiveness of cognitive rehabilitation in PD. It also points out the limitations of the studies indicating the limited availability of follow up data on the long-term effects of cognitive interventions. The review also highlights the fact that some of the studies did not include a PD group who did not undergo training. There remains, therefore, a need for longitudinal studies to investigate the potential long term benefits of cognitive training. In addition, future investigations should examine whether any disease characteristics such as disease stage, degree of cognitive impairment and/or the dominant side (right/left) or specific motor symptoms (rigidity/tremor) influence treatment efficacy.

Feasibility and Acceptability of Computerised Cognitive Training of Everyday Cognition in Parkinson's Disease

Objectives

We piloted a computerised cognitive training battery in a group of participants with Parkinson's disease without dementia to investigate the relevance of the training to daily life and the feasibility and the acceptability of the tasks. Previous studies of CT have had limited success in the benefits of training, extending to improvements in everyday function. By taking a pragmatic approach and targeting training to the cognitive skills affected by Parkinson's disease (planning, attention, and recollection), whilst using tasks that emulated real-life scenarios, we sought to understand whether participants perceived the training to be effective and to identify the elements of the training that elicited beneficial effects.

Methods

Four participants completed a cognitive training session comprising three distinct tasks 5 days a week over two weeks. Participants completed baseline questionnaires examining health-related quality of life, everyday cognition, and apathy before the training period, after the last session, and two weeks after the last session. An interview was held after participants had completed the training.

Results

The findings indicated that participants felt the training was acceptable, enhanced their awareness, and encouraged them to monitor their thinking abilities. The group interview indicated that the training was feasible; participants felt the tasks had potential to improve everyday performance, but more supporting information should be provided to facilitate this transfer. Responses to the questionnaires reflected these findings, indicating improvement for some participants' cognition and quality of life. Objective measures supported the subjective reports; there were improvements in some but not all domains. Performance on the planning and recollection tasks improved over the training period, and the evidence for improvement on the attention task was mixed.

Conclusion

This study has found that pragmatic computer-based training with real-life outcomes is both feasible and acceptable and should be evaluated more extensively using controlled methods.

The impact of cognitive interventions on cognitive symptoms in idiopathic Parkinson's disease: a systematic review

This systematic review addressed efficacy of cognitive stimulation (CS), cognitive training (CT), and cognitive rehabilitation (CR) to improve cognitive functions in Parkinson's disease (PD) with (PD-MCI) and without mild cognitive impairment (PD-H). Five databases were searched. Twelve CT, four CS, and a combination of CT with CR were found. PD-H benefited from CT or CS compared to active or passive controls in 42.1% of cognitive tests, and in 33.3% of psychological and functional measures. PD-MCI alone, compared with controls, only improved in 6.9% of cognitive measures after CT. PD-H and PD-MCI, alone or together, somehow improved information processing speed, attention, working memory, executive functions, and visual episodic memory. PD-MCI improved better than PD-H in global cognition and planning abilities. The outcomes suggest some efficacy of cognitive interventions in PD. However, small samples, lack of information regarding standardization of interventions, and poor methodological quality limit results validity and prevent firm conclusions.

Personalized Telemedicine for Depression in Parkinson's Disease: A Pilot Trial

High rates of depression are observed in Parkinson's disease, and limited access to care complicates management. The purpose of this pilot project was to evaluate the feasibility and impact of a personalized cognitive-behavioral telemedicine program for depression in Parkinson's disease (dPD). Thirty-four individuals with dPD and their carepartners participated in this pilot study. A 10-module self-help workbook, tailored to the unique needs of the dPD population, was created to be used as either a stand-alone intervention, with minimal therapist support, or a supplement to formal telephone-administered cognitive-behavioral therapy sessions. Improvements in depression, anxiety, quality of life, sleep, negative thoughts, and caregiver burden were observed over the course of the 4-month study, independent of treatment modality (guided self-help vs formal telephone-based psychotherapy). Future research will utilize randomized controlled designs and continue to focus on delivery models that can improve access to this and other evidence-based mental health interventions for dPD.

Effectiveness of ReSET; a strategic executive treatment for executive dysfunctioning in patients with Parkinson's disease

In this multicentre randomised controlled trial (RCT), 43 patients with Parkinson's disease (PD) were randomly allocated to either the experimental condition receiving cognitive rehabilitation including strategy training (ReSET; Strategic Executive Treatment, n = 24) or to the control condition receiving computerised repetitive practice training for attention (Cogniplus, n = 16). We expected that strategy training (ReSET) would be more effective than cognitive training (Cogniplus) in improving patients' everyday life executive functioning. Neuropsychological assessment was administered at baseline, at 2 weeks and 3-5 months post-treatment. Primary outcome measure was the Role Resumption List (RRL). Secondary outcome measures were treatment goal attainment (TGA), Dysexecutive Questionnaire (DEX), Parkinson's Disease Questionnaire (PDQ-39), Zarit Burden Interview (ZBI) and neuropsychological tests. No effects of treatment were found on the primary outcome measure and on neuropsychological tests, except for one test of attention. At 2 weeks and 3-5 months post-treatment, PD patients in both the ReSET and Cogniplus group reported a significant improvement in everyday life executive functioning, as measured with TGA and the DEX-self, with an advantage for ReSET only shortly after treatment. Given these results and that PD patients were able to adhere to these treatments despite their motor symptoms and fatigue (i.e., the drop-out rate was small), we conclude that both strategy training and cognitive training for impairments in EF might be beneficial and feasible for PD patients.

Use, maintenance and dose effects of cognitive speed of processing training in Parkinson's disease

INTRODUCTION

Recent research indicated that cognitive speed of processing training (SPT) improved Useful Field of View (UFOV) among individuals with Parkinson's disease (PD). The effects of SPT in PD have not been further examined. The objectives of the current study were to investigate use, maintenance and dose effects of SPT among individuals with PD.

METHODS

Participants who were randomized to SPT or a delayed control group completed the UFOV at a six-month follow-up visit. Use of SPT was monitored across the six-month study period. Regression explored factors affecting SPT use. Mixed effect models were conducted to examine the durability of training gains among those randomized to SPT (n = 44), and training dose effects among the entire sample (n = 87).

RESULTS

The majority of participants chose to continue to use SPT (52%). Those randomized to SPT maintained improvements in UFOV performance. A significant dose effect of SPT was evident such that more hours of training were associated with greater UFOV performance improvements. The cognitive benefits derived from SPT in PD may be maintained for up to three months.

CONCLUSION

Future research should determine how long gains endure and explore if such training gains transfer.

Feasibility of a cognitive strategy training intervention for people with Parkinson's disease

PURPOSE

To investigate the feasibility of a novel client-centered cognitive strategy training intervention for people with Parkinson's disease (PD).

MATERIALS AND METHODS

This was a case series of seven people with PD without dementia but with subjective cognitive decline. The intervention involved ≥5 treatment sessions at the participant's home. Participant acceptance and engagement were assessed by the Credibility/Expectancy Questionnaire (CEQ), Client Satisfaction Questionnaire (CSQ), enjoyment and effort ratings, and homework completion. Logistical information was tracked, and the Canadian Occupational Performance Measure (COPM) was an exploratory outcome measure. Data analysis was descriptive.

RESULTS

CEQ scores were positive and increased over time. CSQ scores were high (M = 30.8, SD = 0.75), with all participants rating all items positively. Almost all (95%) effort and enjoyment ratings were ≥3 (Much), and homework completion rates averaged 84% (SD = 18). Intervention duration was 6-15 weeks (M = 9.2, SD = 2.8), with treatment sessions averaging 1.7 h (SD = 0.5). Group and most individual COPM ratings improved ≥2 points.

CONCLUSIONS

These findings support the feasibility of the intervention for people with PD. It was acceptable, engaging, and promising in terms of its effect on self-identified functional cognitive problems. Implications for Rehabilitation People with Parkinson's disease (PD) without dementia can experience cognitive decline that negatively impacts function and quality of life. Strategy-based interventions that explicitly train for transfer may mitigate the negative functional consequences of cognitive decline in this population. We developed a client-centered cognitive strategy training intervention for people with PD. This small case series supports its feasibility, indicating that it is acceptable and engaging for people with PD and promising in terms of its effect on self-identified functional cognitive problems.

Cognitive Training in Parkinson's Disease: A Review of Studies from 2000 to 2014

Cognitive deficits are prevalent among patients with Parkinson's disease (PD), in both early and late stages of the disease. These deficits are associated with lower quality of life, loss of independence, and institutionalization. To date, there is no effective pharmacological treatment for the range of cognitive impairments presented in PD. Cognitive training (CT) has been explored as an alternative approach to remediating cognition in PD. In this review we present a detailed summary of 13 studies of CT that have been conducted between 2000 and 2014 and a critical examination of the evidence for the effectiveness and applicability of CT in PD. Although the evidence shows that CT leads to short-term, moderate improvements in some cognitive functions, methodological inconsistencies weaken these results. We discuss several key limitations of the literature to date, propose methods of addressing these questions, and outline the future directions that studies of CT in PD should pursue. Studies need to provide more detail about the cognitive profile of participants, include larger sample sizes, be hypothesis driven, and be clearer about the training interventions and the outcome measures.

A pilot study on the effect of cognitive training on BDNF serum levels in individuals with Parkinson's disease

Parkinson's disease (PD) patients, besides motor dysfunctions, may also display mild cognitive deficits (MCI) which increase with disease progression. The neurotrophin brain-derived neurotrophic factor (BDNF) plays a role in the survival of dopaminergic neurons and in the regulation of synaptic connectivity. Moreover, the brain and peripheral level of this protein may be significantly reduced in PD patients. These data suggest that a cognitive rehabilitation protocol aimed at restoring cognitive deficits in PD patients may also involve changes in this neurotrophin. Thus, in this pilot study we evaluated the effect of a cognitive rehabilitation protocol focused on the training of executive functioning and measured BDNF serum levels in a group of PD patients with mild cognitive impairment, as compared to the effect of a placebo treatment (n = 7/8 group). The results showed that PD patients undergoing the cognitive rehabilitation, besides improving their cognitive performance as measured with the Zoo Map Test, also displayed increased serum BDNF levels as compared to the placebo group. These findings suggest that BDNF serum levels may represent a biomarker of the effects of cognitive rehabilitation in PD patients affected by MCI. However, the functional significance of this increase in PD as well as other neuropathological conditions remains to be determined.

Parkinson's patients' executive profile and goals they set for improvement: Why is cognitive rehabilitation not common practice?

Impairments in executive functions (EF) are the core cognitive impairment in patients with Parkinson's disease (PD). Surprisingly, cognitive rehabilitation is not routinely offered to patients with PD. However, in patients with acquired brain injury (ABI), cognitive rehabilitation, in particular strategic executive training, is common practice and has been shown to be effective. In this study, we determined whether PD patients have different needs and aims with regard to strategic executive training than ABI patients, and whether possible differences might be a reason for not offering this kind of cognitive rehabilitation programme to patients with PD. Patients' needs and aims were operationalised by individually set goals, which were classified into domains of EF and daily life. In addition, patients with PD and ABI were compared on their cognitive, in particular EF, profile. Overall, PD patients' goals and cognitive profile were similar to those of patients with ABI. Therefore, based on the findings of this study, there is no reason to assume that strategic executive training cannot be part of standard therapy in PD. However, when strategic executive training is applied in clinical practice, disease-specific characteristics need to be taken into account.

Improving functional disability and cognition in Parkinson disease: randomized controlled trial

Objectives:

To examine the efficacy of an integrative cognitive training program (REHACOP) to improve cognition, clinical symptoms, and functional disability of patients with Parkinson disease (PD).

Methods:

Forty-two patients diagnosed with PD in Hoehn & Yahr stages 1 to 3 were randomly assigned to either the cognitive training group (REHACOP) or the control group (occupational activities) for 3 months (3 sessions, 60 min/wk). Primary outcomes were change on processing speed, verbal memory, visual memory, executive functioning, and theory of mind. Secondary outcomes included changes on neuropsychiatric symptoms, depression, apathy, and functional disability. The trial was registered with clinicaltrials.gov (NCT02118480).

Results:

No baseline group differences were found. Bootstrapped analysis of variance results showed significant differences in the mean change scores between the REHACOP group and control group in processing speed (0.13 [SE = 0.07] vs −0.15 [SE = 0.09], p = 0.025), visual memory (0.10 [SE = 0.10] vs −0.24 [SE = 0.09], p = 0.011), theory of mind (1.00 [SE = 0.37] vs −0.27 [SE = 0.29], p = 0.013), and functional disability (−5.15 [SE = 1.35] vs 0.53 [SE = 1.49], p = 0.012).

Conclusions:

Patients with PD receiving cognitive training with REHACOP demonstrated statistically significant and clinically meaningful changes in processing speed, visual memory, theory of mind, and functional disability. Future studies should consider the long-term effect of this type of intervention. These findings support the integration of cognitive training into the standard of care for patients with PD.

Classification of evidence:

This study provides Class II evidence that for patients with PD, an integrative cognitive training program improves processing speed, visual memory, theory of mind, and functional disability.

Executive dysfunction in Parkinson's disease: a review

Executive dysfunction can be present from the early stages of Parkinson's disease (PD). It is characterized by deficits in internal control of attention, set shifting, planning, inhibitory control, dual task performance, and on a range of decision-making and social cognition tasks. Treatment with dopaminergic medication has variable effects on executive deficits, improving some, leaving some unchanged, and worsening others. In this review, we start by defining the specific nature of executive dysfunction in PD and describe suitable neuropsychological tests. We then discuss how executive deficits relate to pathology in specific territories of the basal ganglia, consider the impact of dopaminergic treatment on executive function (EF) in this context, and review the changes in EFs with disease progression. In later sections, we summarize correlates of executive dysfunction in PD with motor performance (e.g., postural instability, freezing of gait) and a variety of psychiatric (e.g., depression, apathy) and other clinical symptoms, and finally discuss the implications of these for the patients' daily life.

Treatment of psychosis and dementia in Parkinson's disease

OPINION STATEMENT

Parkinson's disease (PD) has been increasingly recognized as having a multitude of nonmotor symptoms including psychosis, cognitive impairment and dementia, mood disturbances, fatigue, apathy, and sleep disorders. Psychosis and dementia, in particular, greatly affect quality of life for both patients and caregivers and are associated with poor outcomes. Safe and effective treatment options for psychosis and dementia in PD are much needed. Antipsychotics with dopamine-blocking properties can worsen parkinsonian motor features and have been associated with increased morbidity and mortality in elderly, dementia patients. For treating PD psychosis, a first step would be eliminating confounding variables, such as delirium, infections, or toxic-metabolic imbalances, followed by simplifying parkinsonian medications as tolerated. If additional treatment is warranted after such interventions, clozapine or quetiapine can be implemented at the low dose levels typically needed by PD patients. Although quetiapine is easy-to-use in clinical settings, does not require blood count monitoring like clozapine, and is anecdotally beneficial, it remains "investigational" in evidence-based medicine reviews. Though not currently available, the novel 5-HT2a inverse agonist, pimavanserin has shown promise in the treatment of PD psychosis. Current treatments for PD dementia are mostly derived from those utilized in Alzheimer's disease, focusing mainly on cholinesterase inhibitors and memantine, a NMDA receptor antagonist. Rivastigmine, the only Food and Drug Administration approved medication for PD dementia, is a reasonable first choice. Other cholinesterase inhibitors and memantine have not yet achieved recommendation status in evidence-based medicine reviews but are well tolerated in studies of PD dementia patients. At present, there are no approved treatments for mild cognitive impairment in PD, but rasagiline, a selective MAO-B inhibitor, and atomoxetine, a serotonin norepinephrine reuptake inhibitor, have been recently studied. Nonpharmacological interventions, including cognitive therapy, physical activity, music and art therapy, and noninvasive brain stimulation techniques, may be promising options for PD cognitive impairment but await rigorous study.

Nonpharmacological therapies for cognitive enhancement in Parkinson’s disease: applying old interventions in a new setting?

SUMMARY Parkinson’s disease (PD) is a neurodegenerative disorder characterized by motor and non-motor features. Among non-motor features, cognitive impairment and the development of dementia is common. Current pharmacological treatment for cognitive impairment is limited and is only licensed for established dementia. Furthermore, pharmacological treatment may not be tolerated by some patients. Therefore, alternative treatment strategies such as nondrug cognition-enhancing therapies may have a role in PD. This article outlines therapies that have been widely used in non-PD dementia and makes recommendations for how they can be adapted to the PD setting.

Non-pharmacological cognitive intervention for aging and dementia: Current perspectives

In recent years, cognitive difficulties associated with normal aging and dementia have been receiving increased attention from both public and scientific communities. With an increase in overall lifespan, promoting healthy cognition has become a priority and a necessity for minimizing and preventing individual and societal burdens associated with cognitive dysfunctions in the elderly. The general awareness concerning the efficacy of preventive (e.g., lifestyles) and palliative treatment strategies of cognitive impairments, related to either healthy or unhealthy trajectories in cognitive aging, is continuously rising. There are several therapeutic strategies which can be broadly classified as either pharmacological or non-pharmacological/psychosocial. In face of the modest evidence for success of pharmacological treatments, especially for dementia related impairments, psychosocial interventions are progressively considered as a complementary treatment. Despite the relative spread of psychosocial interventions in clinical settings, research in this area is rather scarce with evidence for success of these therapies remaining controversial. In this work we provide an evidence based perspective on cognitive intervention(s) for healthy aging, pre-dementia (mild cognitive impairment), and dementia populations. Current evidence and future directions for improving cognitive functions in the elderly are discussed as well.

Cognition, coping, and outcome in Parkinson's disease

BACKGROUND

Cognitive impairment and depression are common and disabling non-motor symptoms of Parkinson's disease (PD). Previous studies have shown associations between them but the nature of the relationship remains unclear. In chronic illness, problem- or task-oriented coping strategies are associated with better outcome but often require higher level cognitive functioning. The present study investigated, in a sample of patients with PD, the relationships between cognitive function, choice of coping strategies, and a broad index of outcome including depression, anxiety, and health-related quality of life (QoL). It was hypothesized that the coping strategy used could mediate the association between cognition and outcome.

METHODS

347 participants completed the Coping Inventory for Stressful Situations, the Hospital Anxiety and Depression Scale, the Parkinson's Disease Questionnaire-8, the Unified Parkinson's Disease Rating Scale, and the Addenbrooke's Cognitive Examination-Revised. Structural Equation Modeling was used to test the hypothesized model of cognition, coping, and outcome based on a direct association between cognition and outcome and an indirect association mediated by coping.

RESULTS

Overall, poorer cognition predicted less use of task-oriented coping, which predicted worse outcome (a latent variable comprised of higher depression and anxiety and lower QoL). The analyses suggested a small indirect effect of cognition on outcome mediated by coping.

CONCLUSIONS

The findings suggest that patients who fail to employ task-oriented coping strategies may be at greater risk of depression, anxiety, and poor health-related QoL. Even mild to moderate cognitive impairment may contribute to reduced use of task-oriented coping. Suitably adapted cognitive-behavioral approaches may be useful to enable the use of adaptive coping strategies in such patients.

Cognitive rehabilitation for executive dysfunction in Parkinson's disease: application and current directions

Cognitive dysfunction in Parkinson's disease contributes to disability, caregiver strain, and diminished quality of life. Cognitive rehabilitation, a behavioral approach to improve cognitive skills, has potential as a treatment option to improve and maintain cognitive skills and increase quality of life for those with Parkinson's disease-related cognitive dysfunction. Four cognitive rehabilitation programs in individuals with PD are identified from the literature. Characteristics of the programs and outcomes are reviewed and critiqued. Current studies on cognitive rehabilitation in PD demonstrate feasibility and acceptability of a cognitive rehabilitation program for patients with PD, but are limited by their small sample size and data regarding generalization of effects over the long term. Because PD involves progressive heterogeneous physical, neurological, and affective difficulties, future cognitive rehabilitation programs should aim for flexibility and individualization, according to each patient's strengths and deficits.