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

Encoding strategy training and self-reported everyday prospective memory in people with Parkinson disease: a randomized-controlled trial

Objective To compare the effects of laboratory-based training in implementation intentions (II; experimental strategy) and verbal rehearsal (VR; control strategy) on self-reported everyday prospective memory among people with Parkinson disease (PD) and to investigate potential correlates of change in self-reported everyday prospective memory in response to this training. Method This was a randomized-controlled trial. Participants with mild to moderate PD without dementia underwent one session of training in either II (n = 25) or VR (n = 27). Then they were instructed to use their strategy as much as possible in their everyday lives to help them remember to do things. The Prospective and Retrospective Memory Questionnaire Prospective Scale (PRMQ-Pro) administered at baseline and one month after training assessed training-related change in self-reported everyday prospective memory. Baseline depressive symptoms, perceptions of the strategy (credibility, expectancy), prospective memory-related awareness, global cognition, and disease severity were correlated to PRMQ-Pro Change scores (post minus pre) to determine their association with response to training. Results The VR group's PRMQ-Pro scores declined from pre to post training, while the II group's remained stable (p = .03). This effect was driven by change in self-cued everyday prospective memory tasks. Higher baseline depressive symptoms, treatment expectancy, and global cognition related to better response to training in the II group (rs ≤ -.40, ps ≤ .05). Conclusions II training may prevent everyday prospective memory decline among people with PD. In addition, people with higher depression, stronger expectations of improvement from strategy training, or better global cognition may benefit the most from II training.

Nonmotor Symptoms and Natural History of Parkinson's Disease: Evidence From Cognitive Dysfunction and Role of Noninvasive Interventions

Parkinson's disease (PD) is a common neurodegenerative disorder, characterized by motor and nonmotor symptoms (NMS). Several subsequent studies substantiate the great functional burden related to NMS, their progression, and negative effect on quality of life in PD. Additional evidence indicates interesting relationships between striatal dopaminergic function and NMS. The basal ganglia are implicated in the modulation and integration of sensory information and pain, bladder function is under control of both inhibitory (D1) and facilitatory (D2) dopaminergic inputs, finally reduced dopaminergic activity in the mesocortical and mesolimbic pathways is involved in the development of several NMS including mood, motivational, and cognitive alterations. Some NMS fluctuate in response to dopaminergic treatment and are relieved by dopamine replacement therapy, other are insensitive to current therapeutic strategies. The relation among the overall disease complications, perhaps the most important for PD patients and family members' well-being and functionality is dementia that affects most PD patients over the course of disease. Specific pharmacological treatment is lacking, and alternative approaches have been implemented to improve everyday functionality and quality of life. The state of the art suggests that cognitive rehabilitation in PD is possible and may either increase performance or preserve cognitive level over the time. However, it is also evident that cognitive abnormalities in PD are heterogeneous and we still do not have biomarkers to detect early patients at risk for dementia. Cognitive dysfunction is one the most prevalent NMS and is a clinically and functionally important disease milestone. Given the available clinical and imaging evidence it is possible to use cognition to model NMS progression and design nonpharmacological interventions. In this chapter we will address the use of cognitive rehabilitation and noninvasive brain stimulation techniques to modulate cognitive performance and rescue connectivity in affected brain circuitry.

Cognitive Training and Noninvasive Brain Stimulation for Cognition in Parkinson's Disease: A Meta-analysis

BACKGROUND

Many people with Parkinson's disease (PD) experience cognitive decline. It is not known whether cognitive training or noninvasive brain stimulation are effective at alleviating cognitive deficits in PD.

OBJECTIVE

To examine cognitive training and non-invasive brain stimulation interventions for cognition in PD.

METHODS

An extensive search was conducted of published and unpublished studies in online databases. Studies were selected if they were controlled trials examining standard (not individualized) or tailored (individualized) cognitive training, repetitive transcranial magnetic stimulation (rTMS), or transcranial direct current stimulation (tDCS) in PD, with outcomes measured by standardized neuropsychological tests.

RESULTS

Fourteen controlled trials met inclusion criteria. For executive function, the pooled effect size (Hedges' g) for cognitive training (standard and tailored combined) was small ( g = 0.42) but statistically significant (95% CI 0.15-0.68). The pooled effect for standard cognitive training (alone) was medium ( g = 0.51) and significant (95% CI 0.16-0.85). For attention/working memory, small pooled effect sizes were found when combining standard and tailored cognitive training ( g = 0.23; 95% CI 0.02-0.44) and for standard cognitive training alone ( g = 0.29; 95% CI 0.04-0.53), both significant. For memory, small but significant pooled effect sizes were also found when combining standard and tailored cognitive training and for standard cognitive training alone.

CONCLUSIONS

The results suggest that standard and tailored cognitive training may improve executive function, attention/working memory, and memory in PD. Future studies must adopt randomized controlled trial designs to explore the therapeutic potential of these interventions.

Dynamics of change in self-reported disability among persons with Parkinson's disease after 2 years of follow-up

Symptoms of Parkinson's disease (PD) progress over time causing significant disability. Yet, change in disability over shorter time periods has not been entirely understood. The purpose of this study was to assess the Self-Assessment Disability Scale (SADS) in persons with Parkinson's disease (PD) after 2 years of follow-up and compare it with the score observed at baseline. Additionally, we aimed at evaluating association of motor and non-motor PD features at baseline with a higher disability after 2 years of follow-up. A total of 120 consecutive persons with PD, who denied falling in the past 6 months, were initially recruited. After 2 years of follow-up, 88 (73.3%) persons with PD were evaluated for SADS. The total disability (SADS) score did not change after follow-up (p = 0.529). We observed increase in difficulty at "Getting out of bed" (p = 0.006), "Getting up out of armchair" (p = 0.013), "Walking about house/flat" (p = 0.003), "Walking outside" (p = 0.010), and "Traveling by public transport" (p = 0.014). After adjusting for several potential confounding factors, falls in the past year (β = 8.32, 95% confidence interval (CI) 1.04-15.59) and higher Unified Parkinson's Disease Rating Scale part 3 at baseline (β = 0.26, 95%CI 0.01-0.51) remained associated with higher PD-related disability. This finding suggests that accumulation of overall PD-related disability tends to occur over a longer time span. Further studies are needed to gradually assess long-term evolution of disability in PD.

Combining social cognitive treatment, cognitive remediation, and functional skills training in schizophrenia: a randomized controlled trial

This study examined the efficacy of an integrative cognitive remediation program (REHACOP) in improving cognition and functional outcome in patients with schizophrenia. The program combines cognitive remediation, social cognitive intervention, and functional skills training. Few studies have attempted this approach. One hundred and eleven patients diagnosed with schizophrenia were randomly assigned to either the cognitive remediation group (REHACOP) or an active control group (occupational activities) for 4 months (three sessions per week, 90 min). Primary outcomes were change on general neurocognitive performance and social cognition, including theory of mind (ToM), emotion perception (EP), attributional style, and social perception (SP). Secondary outcomes included changes on clinical symptoms (Positive and Negative Syndrome Scale) and functional outcome (UCSD Performance-Based Skills Assessment and the Global Assessment of Functioning). The trial was registered with clinicaltrials.gov (NCT02796417). No baseline group differences were found. Significant differences were found in the mean change between the REHACOP group and control group in neurocognition (ηp2=0.138), SP (ηp2=0.082), ToM (ηp2=0.148), EP (ηp2=0.071), negative symptoms (ηp2=0.082), emotional distress (ηp2=0.136), Global Assessment of Functioning (ηp2=0.081), and UCSD Performance-Based Skills Assessment (ηp2=0.154). The combination of cognitive remediation, social cognitive intervention, and functional skills training demonstrated statistically significant and clinically meaningful changes in neurocognition, social cognition, negative, and functional disability.

Global cognitive function and processing speed are associated with gait and balance dysfunction in Parkinson's disease

Background

Our primary objective was to determine the relationship between global cognitive function and specific domains of gait and balance in a cohort of Parkinson’s disease (PD) subjects. In a secondary analysis, we determined whether specific cognitive domains correlated with gait and balance performance.

Methods

Fourteen PD subjects (mean age 61.1 ± 7.8 years) were recruited from the Rush University Medical Center Movement Disorders clinic. Subjects underwent clinical assessment using the motor subsection of the Unified Parkinson’s Disease Rating Scale (UPDRS) followed by quantitative gait and balance assessments using the APDM Mobility Lab™ system (Mobility Lab, APDM Inc., Portland, OR). Subjects completed global cognitive testing using the Mattis Dementia Rating Scale (MDRS) as well as domain specific cognitive measures. Spearman’s rho was used to assess correlations between cognitive measures and gait and balance function, with False Discovery Rate (FDR) correction for multiple comparisons.

Results

Global cognitive function had the strongest correlation with stride velocity (r = 0.816, p = 0.001), turn duration (r = −0.806, p = 0.001), number of steps to turn (r = −0.830, p = 0.001), and mean velocity of postural sway in the medio-lateral direction (r = −0.726, p = 0.005). A significant correlation was found between processing speed and two turning measures (turn duration, r = −0.884, p = 0.001; number of steps to turn, r = −0.954, p < 0.001), but no other associations were found between specific cognitive domains and gait domains.

Conclusions

This pilot study provides preliminary data regarding the association between global cognitive function and pace-related measures of gait, turning, and postural sway. Furthermore, reduced processing speed was found to be associated with difficulty in performing turns.

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.

Parkinson Disease and Dementia

Dementia is a frequent complication of Parkinson disease (PD) with a yearly incidence of around 10% of patients with PD. Lewy body pathology is the most important factor in the development of Parkinson disease dementia (PDD) and there is evidence for a synergistic effect with β-amyloid. The clinical phenotype in PDD extends beyond the dysexecutive syndrome that is often present in early PD and encompasses deficits in recognition memory, attention, and visual perception. Sleep disturbances, hallucinations, neuroleptic sensitivity, and fluctuations are often present. This review provides an update on current knowledge of PDD including aspects of epidemiology, pathology, clinical presentation, management, and prognosis.

Establishing an evidence-base framework for driving rehabilitation in Parkinson's disease: A systematic review of on-road driving studies

BACKGROUND

Individuals with Parkinson's disease (PD) experience problems with on-road driving that can be targeted in driving rehabilitation programs.

OBJECTIVE

To provide a framework for driving rehabilitation in PD by identifying the critical on-road driving impairments and their associated visual, cognitive, and motor deficits.

METHODS

We conducted a systematic review of the literature on on-road driving and naturalistic driving practices in PD. Relevant databases including Pubmed, Medline, PsychINFO, ISI Web of Science, Cochrane library, and ClinicalTrials.gov, were reviewed using the key words Parkinson's disease, on-road driving, naturalistic driving, and their related entry words. On-road driving skills were mapped onto an existing theoretic model of operational, tactical, and strategic levels. The on-road and off-road cognitive, motor, and visual predictors of global on-road driving were summarized.

RESULTS

Twenty-seven studies were included. All but one study were prospective and Class II studies according to the American Academy of Neurology Classification Criteria. Participants were on average 68 years old and in the mild to moderate stages of PD. Drivers with PD were more likely to fail a driving assessment compared to age- and gender-matched controls. Compared with controls, drivers with PD experienced difficulties on all levels of driving skill. However, the compensation strategies on the strategic level showed that drivers with PD were aware of their diminished driving skills on the operational and strategic levels. Operational and tactical on-road driving skills best predicted global on-road driving. A combination of visual, cognitive, and motor deficits underlie impaired on-road driving performance in PD.

CONCLUSION

Driving rehabilitation strategies for individuals with PD should include training of operational and tactical driving skills or indirect comprehensive training program of visual, cognitive, and motor skills.

Neuroanatomical Correlates of Theory of Mind Deficit in Parkinson's Disease: A Multimodal Imaging Study

BACKGROUND

Parkinson's disease (PD) patients show theory of mind (ToM) deficit since the early stages of the disease, and this deficit has been associated with working memory, executive functions and quality of life impairment. To date, neuroanatomical correlates of ToM have not been assessed with magnetic resonance imaging in PD. The main objective of this study was to assess cerebral correlates of ToM deficit in PD. The second objective was to explore the relationships between ToM, working memory and executive functions, and to analyse the neural correlates of ToM, controlling for both working memory and executive functions.

METHODS

Thirty-seven PD patients (Hoehn and Yahr median = 2.0) and 15 healthy controls underwent a neuropsychological assessment and magnetic resonance images in a 3T-scanner were acquired. T1-weighted images were analysed with voxel-based morphometry, and white matter integrity and diffusivity measures were obtained from diffusion weighted images and analysed using tract-based spatial statistics.

RESULTS

PD patients showed impairments in ToM, working memory and executive functions; grey matter loss and white matter reduction compared to healthy controls. Grey matter volume decrease in the precentral and postcentral gyrus, middle and inferior frontal gyrus correlated with ToM deficit in PD. White matter in the superior longitudinal fasciculus (adjacent to the parietal lobe) and white matter adjacent to the frontal lobe correlated with ToM impairment in PD. After controlling for executive functions, the relationship between ToM deficit and white matter remained significant for white matter areas adjacent to the precuneus and the parietal lobe.

CONCLUSIONS

Findings reinforce the existence of ToM impairment from the early Hoehn and Yahr stages in PD, and the findings suggest associations with white matter and grey matter volume decrease. This study contributes to better understand ToM deficit and its neural correlates in PD, which is a basic skill for development of healthy social relationships.

Cognitive training in Parkinson disease: A systematic review and meta-analysis

Objective:

To quantify the effects of cognitive training (CT) on cognitive and behavioral outcome measures in patients with Parkinson disease (PD).

Methods:

We systematically searched 5 databases for randomized controlled trials (RCTs) of CT in patients with PD reporting cognitive or behavioral outcomes. Efficacy was measured as standardized mean difference (Hedges g) of post-training change.

Results:

Seven studies encompassing 272 patients with Hoehn & Yahr Stages 1–3 were included. The overall effect of CT over and above control conditions was small but statistically significant (7 studies: g = 0.23, 95% confidence interval [CI] 0.014–0.44, p = 0.037). True heterogeneity across studies was low (I² = 0%) and there was no evidence of publication bias. Larger effect sizes were noted on working memory (4 studies: g = 0.74, CI 0.32–1.17, p = 0.001), processing speed (4 studies: g = 0.31, CI 0.01–0.61, p = 0.04), and executive function (5 studies: g = 0.30, CI 0.01–0.58, p = 0.042), while effects on measures of global cognition (4 studies), memory (5 studies), visuospatial skills (4 studies), and depression (5 studies), as well as attention, quality of life, and instrumental activities of daily living (3 studies each), were not statistically significant. No adverse events were reported.

Conclusions:

Though still small, the current body of RCT evidence indicates that CT is safe and modestly effective on cognition in patients with mild to moderate PD. Larger RCTs are necessary to examine the utility of CT for secondary prevention of cognitive decline in this population.

Nonpharmacological treatments for patients with Parkinson's disease

Since 2013, a number of studies have enhanced the literature and have guided clinicians on viable treatment interventions outside of pharmacotherapy and surgery. Thirty-three randomized controlled trials and one large observational study on exercise and physiotherapy were published in this period. Four randomized controlled trials focused on dance interventions, eight on treatment of cognition and behavior, two on occupational therapy, and two on speech and language therapy (the latter two specifically addressed dysphagia). Three randomized controlled trials focused on multidisciplinary care models, one study on telemedicine, and four studies on alternative interventions, including music therapy and mindfulness. These studies attest to the marked interest in these therapeutic approaches and the increasing evidence base that places nonpharmacological treatments firmly within the integrated repertoire of treatment options in Parkinson's disease.