How well do we recognise non-motor symptoms in a British Parkinson’s disease population? J Neurol. 2011;258:1513-1517. [PMID: 21394490 DOI: 10.1007/s00415-011-5972-6]

Basal ganglia theta power indexes trait anxiety in people with Parkinson's disease

Neuropsychiatric symptoms are common and disabling in Parkinson's disease, with troublesome anxiety occurring in one-third of patients. Management of anxiety in Parkinson's disease is challenging, hampered by insufficient insight into underlying mechanisms, lack of objective anxiety measurements and largely ineffective treatments. In this study, we assessed the intracranial neurophysiological correlates of anxiety in patients with Parkinson's disease treated with deep brain stimulation (DBS) in the laboratory and at home. We hypothesized that low-frequency (theta-alpha) activity would be associated with anxiety. We recorded local field potentials from subthalamic nucleus or globus pallidus pars interna DBS implants in three Parkinson's disease cohorts: (i) patients with recordings (subthalamic nucleus) performed in hospital at rest via perioperatively externalized leads, without active stimulation, both ON and OFF dopaminergic medication; (ii) patients with recordings (subthalamic nucleus or globus pallidus pars interna) performed at home while resting, via a chronically implanted commercially available sensing-enabled neurostimulator (Medtronic Percept™ device), ON dopaminergic medication, with stimulation both on and off; and (iii) patients with recordings performed at home while engaging in a behavioural task via subthalamic nucleus and globus pallidus pars interna leads and electrocorticography paddles over the premotor cortex connected to an investigational sensing-enabled neurostimulator, ON dopaminergic medication, with stimulation both on and off. Trait anxiety was measured with validated clinical scales in all participants, and state anxiety was measured with momentary assessment scales at multiple time points in the two at-home cohorts. Power in theta (4-8 Hz) and alpha (8-12 Hz) ranges was extracted from the local field potential recordings, and its relationship with anxiety ratings was assessed using linear mixed-effects models. In total, 33 patients with Parkinson's disease (59 hemispheres) were included. Across three independent cohorts, with stimulation off, basal ganglia theta power was positively related to trait anxiety (all P < 0.05). Also in a naturalistic setting, with individuals at home, at rest, with stimulation and medication ON, basal ganglia theta power was positively related to trait anxiety (P < 0.05). This relationship held regardless of the hemisphere and DBS target. There was no correlation between trait anxiety and premotor cortical theta-alpha power. There was no within-patient association between basal ganglia theta-alpha power and state anxiety. We showed that basal ganglia theta activity indexes trait anxiety in Parkinson's disease. Our data suggest that theta could be a possible physiomarker of neuropsychiatric symptoms and specifically of anxiety in Parkinson's disease, potentially suitable for guiding advanced DBS treatment tailored to the needs of the individual patient, including non-motor symptoms.

Basal ganglia theta power indexes trait anxiety in people with Parkinson's disease

Background

Neuropsychiatric symptoms are common and disabling in Parkinson's disease (PD), with troublesome anxiety occurring in one-third of patients. Management of anxiety in PD is challenging, hampered by insufficient insight into underlying mechanisms, lack of objective anxiety measurements, and largely ineffective treatments.In this study, we assessed the intracranial neurophysiological correlates of anxiety in PD patients treated with deep brain stimulation (DBS) in the laboratory and at home. We hypothesized that low-frequency (theta-alpha) activity would be associated with anxiety.

Methods

We recorded local field potentials (LFP) from the subthalamic nucleus (STN) or the globus pallidus pars interna (GPi) DBS implants in three PD cohorts: 1) patients with recordings (STN) performed in hospital at rest via perioperatively externalized leads, without active stimulation, both ON or OFF dopaminergic medication; 2) patients with recordings (STN or GPi) performed at home while resting, via a chronically implanted commercially available sensing-enabled neurostimulator (Medtronic Percept™ device), ON dopaminergic medication, with stimulation both ON or OFF; 3) patients with recordings performed at home while engaging in a behavioral task via STN and GPi leads and electrocorticography paddles (ECoG) over premotor cortex connected to an investigational sensing-enabled neurostimulator, ON dopaminergic medication, with stimulation both ON or OFF.Trait anxiety was measured with validated clinical scales in all participants, and state anxiety was measured with momentary assessment scales at multiple time points in the two at-home cohorts. Power in theta (4-8 Hz) and alpha (8-12 Hz) ranges were extracted from the LFP recordings, and their relation with anxiety ratings was assessed using linear mixed-effects models.

Results

In total, 33 PD patients (59 hemispheres) were included. Across three independent cohorts, with stimulation OFF, basal ganglia theta power was positively related to trait anxiety (all p<0.05). Also in a naturalistic setting, with individuals at home at rest with stimulation and medication ON, basal ganglia theta power was positively related to trait anxiety (p<0.05). This relationship held regardless of the hemisphere and DBS target. There was no correlation between trait anxiety and premotor cortical theta-alpha power. There was no within-patient association between basal ganglia theta-alpha power and state anxiety.

Conclusion

We showed that basal ganglia theta activity indexes trait anxiety in PD. Our data suggest that theta could be a possible physiomarker of neuropsychiatric symptoms and specifically of anxiety in PD, potentially suitable for guiding advanced DBS treatment tailored to the individual patient's needs, including non-motor symptoms.

Experiences of Living With the Nonmotor Symptoms of Parkinson's Disease: A Photovoice Study

BACKGROUND

Nonmotor symptoms (NMSs) are frequently experienced by people with Parkinson's disease (PD) and are often perceived as their most bothersome symptoms. However, these remain poorly understood with suboptimal clinical management. These unmet needs are an important determinant of health-related quality of life (QoL) in PD.

OBJECTIVE

The aim of this study was to gain insights into the experience of living with the NMS of PD in real-time using participatory action methodology.

METHOD

Using the photovoice method, 14 people with PD took photographs to document their experiences of living with the NMS of PD. They composed corresponding written narratives to capture the impact of NMS on their daily activities and QoL. In total, 152 photographs and corresponding narratives were analysed using thematic analysis with an inductive approach.

RESULTS

Four interrelated themes were identified. Emotional well-being and sense of self encompassed a process of adjustment to living with PD. Engaging in valued activities, adopting a positive mindset and utilising coping strategies were thought to enhance confidence and self-esteem. Social support and societal awareness highlighted the importance of supportive relationships and socialising to aid participation and avoid isolation. Barriers to social engagement included the unpredictability of NMS and nonvisible NMS being neglected or misunderstood.

CONCLUSION

Findings demonstrated the far-reaching impact of nonmotor aspects of PD on emotional, occupational and social dimensions. These needs could be addressed through person-centred and comprehensive approaches to care.

PATIENT OR PUBLIC CONTRIBUTION

This study utilised a participatory research approach allowing participants to choose the subjects that mattered to them and how to present their results. Additionally, a group workshop was held with people with PD, their family members and healthcare professionals to guide theme development.

Does a novel community-based outpatient palliative care intervention for Parkinson's disease and related disorders improve care? Qualitative results from patients and care partners

BACKGROUND

Palliative care has the potential to address significant unmet needs in people with Parkinson's disease and related disorders, but models that rely on in-person specialty palliative care teams have limited scalability.

AIM

To describe patient and care partner experiences with a novel, community-based palliative care intervention for Parkinson's disease.

DESIGN

Qualitative study embedded in a randomized clinical trial to document participant experiences with a novel palliative care intervention (community neurologist training and remote team-based specialist palliative care). Transcripts were coded and thematically analyzed through a combination of team-based inductive and deductive coding.

SETTING/PARTICIPANTS

Twenty-eight patients and 33 care partners purposively sampled from participants in a randomized clinical trial of a palliative care intervention for Parkinson's disease and related disorders conducted at nine sites.

RESULTS

Benefits of the intervention included management of a wider range of non-motor symptoms, facilitation of conversations about the future, greater engagement with the health care team, and increased referrals to resources. Participants identified areas of improvement, including uptake of palliative care training by community neurologists, additional prognostic counseling, and clarity and timeliness of communication with the multidisciplinary team.

CONCLUSIONS

Clinicians caring for people with Parkinson's disease and related disorders should screen for non-motor symptoms, provide regular prognostic counseling, and refer to specialty palliative care services earlier in the course of illness. Future interventions should be designed to promote uptake of palliative care training by community neurologists and further optimize referral to and coordination with in-person or remote specialty palliative teams.

Feasibility and Acceptability of a Videoconferencing CBT Intervention for Anxiety in People with Parkinson's Disease

OBJECTIVES

In people with Parkinson's disease (PwPD), non-motor symptoms such as anxiety are common and have negative impacts on their quality of life. There are currently few interventions that address anxiety in PwPD, and access to diagnosis and treatment is often limited for those living in rural areas. The aim of this study was to evaluate the feasibility and acceptability of a telehealth videoconferencing CBT intervention for anxiety in PwPD.

METHODS

A pre- and post-test feasibility study (N = 10) was conducted and evaluated utilizing the RE-AIM framework (Reach, Effectiveness, Adoption, Implementation, and Maintenance).

RESULTS

Lack of access to the internet and videoconferencing technology were identified as barriers to participation. Physical health issues also impacted recruitment and retention. Non-completers were significantly older and less likely to have a carer involved in the intervention. Clinician adoption of the intervention was low while participant acceptability of videoconferencing technology varied and required carer support.

CONCLUSIONS

Providing access to technology and support to overcome technological issues, as well as telehealth training for clinicians, are recommended in future studies to improve recruitment, retention, and implementation.

CLINICAL IMPLICATIONS

Identification of barriers and facilitators provides future studies with the knowledge to tailorize their program to better suit PwPD.

A mouse model of sleep disorders in Parkinson's disease showing distinct effects of dopamine D2-like receptor activation

Excessive daytime sleepiness (EDS) and sleep fragmentation are often observed in Parkinson's disease (PD) patients and are poorly understood despite their considerable impact on quality of life. We examined the ability of a neurotoxin-based mouse model of PD to reproduce these disorders and tested the potential counteracting effects of dopamine replacement therapy. Experiments were conducted in female mice with a unilateral 6-hydroxydopamine lesion of the medial forebrain bundle, leading to the loss of dopamine neurons projecting to the dorsal and ventral striatum. Sham-operated mice were used as control. Electroencephalographic and electromyographic recording was used to identify and quantify awaken, rapid eye movement (REM) and non-REM (NREM) sleep states. PD mice displayed enhanced NREM sleep and reduced wakefulness during the active period of the 24-hour circadian cycle, indicative of EDS. In addition, they also showed fragmentation of NREM sleep and increased slow-wave activity, a marker of sleep pressure. Electroencephalographic analysis of the PD model also revealed decreased density and increased length of burst-like thalamocortical oscillations (spindles). Treatment of PD mice with the dopamine receptor agonist, pramipexole, but not with L-DOPA, counteracted EDS by reducing the number, but not the length, of NREM sleep episodes during the first half of the active period. The present model recapitulates some prominent PD-related anomalies affecting sleep macro- and micro-structure. Based on the pharmacological profile of pramipexole these results also indicate the involvement of impaired dopamine D2/D3 receptor transmission in EDS.

Detecting Parkinson's disease and its cognitive phenotypes via automated semantic analyses of action stories

Action-concept outcomes are useful targets to identify Parkinson's disease (PD) patients and differentiate between those with and without mild cognitive impairment (PD-MCI, PD-nMCI). Yet, most approaches employ burdensome examiner-dependent tasks, limiting their utility. We introduce a framework capturing action-concept markers automatically in natural speech. Patients from both subgroups and controls retold an action-laden and a non-action-laden text (AT, nAT). In each retelling, we weighed action and non-action concepts through our automated Proximity-to-Reference-Semantic-Field (P-RSF) metric, for analysis via ANCOVAs (controlling for cognitive dysfunction) and support vector machines. Patients were differentiated from controls based on AT (but not nAT) P-RSF scores. The same occurred in PD-nMCI patients. Conversely, PD-MCI patients exhibited reduced P-RSF scores for both texts. Direct discrimination between patient subgroups was not systematic, but it yielded best outcomes via AT scores. Our approach outperformed classifiers based on corpus-derived embeddings. This framework opens scalable avenues to support PD diagnosis and phenotyping.

The Parkinson's Disease-Cognitive Rating Scale: Greek Normative Data, Clinical Utility and Cultural Considerations

BACKGROUND

The Parkinson's Disease-Cognitive Rating Scale (PD-CRS) is a comprehensive screening procedure for the evaluation of cognitive impairment in patients with Parkinson's disease (PD).

OBJECTIVES

In the present study we adjusted the PD-CRS for the Greek population, developed normative data and examined its clinical utility for the assessment of cognitive functioning in Greek PD patients. In addition, the correlation of clinical characteristics with cognitive performance in PD patients was examined.

METHODS

Three hundred four community-dwelling healthy adults and 59 patients with PD, completed the adapted PD-CRS.

RESULTS

Healthy adults outperformed the PD patients on the total, the cortical and subcortical scores of the PD-CRS. Normative data indicated effects of both education and age on the PD-CRS. The optimal total PD-CRS cutoff score for the identification of cognitive impairment in a heterogeneous sample of PD patients, with regard to the severity of cognitive difficulties, was 79, yielding a modest sensitivity and specificity. Clinical characteristics of the patients (i.e., disease duration and functional disease burden) were related to poor performance on the PD-CRS.

CONCLUSIONS

The Greek version of the PD-CRS is a useful instrument for the assessment of cognition in PD. Future prospective studies should examine its clinical utility to identify PD-cognitive subtypes (i.e., PD patients with mild cognitive impairment), to monitor cognitive changes, as well as its predictive accuracy for subsequent dementia.

Advance Care Planning and Care Coordination for People With Parkinson's Disease and Their Family Caregivers-Study Protocol for a Multicentre, Randomized Controlled Trial

Background: Parkinson's disease (PD) is a progressive neurodegenerative disease with motor- and non-motor symptoms. When the disease progresses, symptom burden increases. Consequently, additional care demands develop, the complexity of treatment increases, and the patient's quality of life is progressively threatened. To address these challenges, there is growing awareness of the potential benefits of palliative care for people with PD. This includes communication about end-of-life issues, such as Advance Care Planning (ACP), which helps to elicit patient's needs and preferences on issues related to future treatment and care. In this study, we will assess the impact and feasibility of a nurse-led palliative care intervention for people with PD across diverse European care settings.

Methods: The intervention will be evaluated in a multicentre, open-label randomized controlled trial, with a parallel group design in seven European countries (Austria, Estonia, Germany, Greece, Italy, Sweden and United Kingdom). The “PD_Pal intervention” comprises (1) several consultations with a trained nurse who will perform ACP conversations and support care coordination and (2) use of a patient-directed “Parkinson Support Plan-workbook”. The primary endpoint is defined as the percentage of participants with documented ACP-decisions assessed at 6 months after baseline (t1). Secondary endpoints include patients' and family caregivers' quality of life, perceived care coordination, patients' symptom burden, and cost-effectiveness. In parallel, we will perform a process evaluation, to understand the feasibility of the intervention. Assessments are scheduled at baseline (t0), 6 months (t1), and 12 months (t2). Statistical analysis will be performed by means of Mantel–Haenszel methods and multilevel logistic regression models, correcting for multiple testing.

Discussion: This study will contribute to the current knowledge gap on the application of palliative care interventions for people with Parkinson's disease aimed at ameliorating quality of life and managing end-of-life perspectives. Studying the impact and feasibility of the intervention in seven European countries, each with their own cultural and organisational characteristics, will allow us to create a broad perspective on palliative care interventions for people with Parkinson's disease across settings.

Clinical Trial Registration:www.trialregister.nl, NL8180.

Cognitive Determinants of Dysarthria in Parkinson's Disease: An Automated Machine Learning Approach

BACKGROUND

Dysarthric symptoms in Parkinson's disease (PD) vary greatly across cohorts. Abundant research suggests that such heterogeneity could reflect subject-level and task-related cognitive factors. However, the interplay of these variables during motor speech remains underexplored, let alone by administering validated materials to carefully matched samples with varying cognitive profiles and combining automated tools with machine learning methods.

OBJECTIVE

We aimed to identify which speech dimensions best identify patients with PD in cognitively heterogeneous, cognitively preserved, and cognitively impaired groups through tasks with low (reading) and high (retelling) processing demands.

METHODS

We used support vector machines to analyze prosodic, articulatory, and phonemic identifiability features. Patient groups were compared with healthy control subjects and against each other in both tasks, using each measure separately and in combination.

RESULTS

Relative to control subjects, patients in cognitively heterogeneous and cognitively preserved groups were best discriminated by combined dysarthric signs during reading (accuracy = 84% and 80.2%). Conversely, patients with cognitive impairment were maximally discriminated from control subjects when considering phonemic identifiability during retelling (accuracy = 86.9%). This same pattern maximally distinguished between cognitively spared and impaired patients (accuracy = 72.1%). Also, cognitive (executive) symptom severity was predicted by prosody in cognitively preserved patients and by phonemic identifiability in cognitively heterogeneous and impaired groups. No measure predicted overall motor dysfunction in any group.

CONCLUSIONS

Predominant dysarthric symptoms appear to be best captured through undemanding tasks in cognitively heterogeneous and preserved cohorts and through cognitively loaded tasks in patients with cognitive impairment. Further applications of this framework could enhance dysarthria assessments in PD. © 2021 International Parkinson and Movement Disorder Society.

The effect of directional social cues on saccadic eye movements in Parkinson's disease

There is growing interest in how social processes and behaviour might be affected in Parkinson’s disease. A task which has been widely used to assess how people orient attention in response to social cues is the spatial cueing task. Socially relevant directional cues, such as a picture of someone gazing or pointing to the left or the right have been shown to cause orienting of visual attention in the cued direction. The basal ganglia may play a role in responding to such directional cues, but no studies to date have examined whether similar social cueing effects are seen in people with Parkinson’s disease. In this study, patients and healthy controls completed a prosaccade (Experiment 1) and an antisaccade task (Experiment 2) in which the target was preceded by arrow, eye gaze or pointing finger cues. Patients showed increased errors and response times for antisaccades but not prosaccades. Healthy participants made most anticipatory errors on pointing finger cue trials, but Parkinson's patients were equally affected by arrow, eye gaze and pointing cues. It is concluded that Parkinson's patients have a reduced ability to suppress responding to directional cues, but this effect is not specific to social cues.

Annual Prevalence of Use of Potentially Inappropriate Medications for Treatment of Affective Disorders in Parkinson's Disease

OBJECTIVE

To examine the national prevalence of pharmacological treatment of affective disorders in older adults with Parkinson's disease (PD), and determine the prevalence and risk factors for receipt of an American Geriatrics Society Beers Criteria® defined potentially inappropriate medication (PIM) for affective disorder treatment.

DESIGN

Cross-sectional analysis of 2014 Medicare data.

SETTING

Research Identifiable File data from the Centers for Medicare and Medicaid Services.

PARTICIPANTS

Individuals ≥65 years of age with PD whose inpatient, outpatient, and prescription care is administered through the U.S. Medicare Program.

MEASUREMENTS

The 2014 prevalence of affective (i.e., depressive and anxiety) disorders was calculated. We assessed prescription fills for affective disorder treatment and classified prescriptions according to PIM status. Patient and clinician factors associated with PIM prescriptions were determined.

RESULTS

Of 84,323 beneficiaries with PD, 15.1% had prevalent depression only, 7.5% had anxiety only, and 8.5% had comorbid depression and anxiety. Among those with depression only, 80.7% were treated in 2014 (12.8% of treated received at least one PIM). The annual treatment prevalence was 62.9% (75.9% PIM) and 93.1% (63.9% PIM) in the anxiety only and comorbid group, respectively. In most groups, PIM use was less likely among men and those with dementia; geriatricians were less likely to prescribe PIMs.

CONCLUSION

Treatment of affective disorders in persons diagnosed with PD is high. PIM use is also common, particularly in persons with anxiety. Future research will quantify the potential effects of these PIMs on clinical and patient outcomes.

Symptom burden among individuals with Parkinson disease: A national survey

OBJECTIVE

To explore disease burden in Parkinson disease (PD) by evaluating the prevalence of symptoms and key disease milestones (critical events, e.g., hospitalization or frequent falls) and their association with quality of life (QOL) in those with PD.

METHODS

We created and pretested an online needs assessment survey to evaluate the clinical characteristics, QOL, symptom prevalence, and critical event frequency among those with PD. We recruited individuals with self-reported Hoehn and Yahr stage II-V PD through online postings and email through the Davis Phinney Foundation. We used logistic regression to evaluate the association between a large number of uncontrolled symptoms and events on QOL.

RESULTS

A total of 612 individuals (mean age 70.1 years, 49.8% women) completed the survey. Among respondents, 13.6% reported poor QOL. Nearly 20% of respondents reported >3 falls, and 15% of respondents had been hospitalized over the previous 6 months. Participants had an average of 5.1 uncontrolled symptoms, with 86.1% of respondents reporting at least 1 uncontrolled symptom; more than 10% of respondents reported >10 uncontrolled symptoms. Depression, confusion, pain, and bothersome hallucinations were associated with poor QOL among the cohort.

CONCLUSIONS

In this national survey of individuals with PD, we identified poor QOL, frequent critical events, and numerous uncontrolled symptoms among a substantial proportion of respondents. Although motor symptoms were common, only nonmotor symptoms were associated with poor QOL. Many of these symptoms and events are treatable or preventable, highlighting the need for better identification and management to improve QOL among those with PD.

Framing advance care planning in Parkinson disease: Patient and care partner perspectives

OBJECTIVE

Advance care planning (ACP) is a core quality measure in caring for individuals with Parkinson disease (PD) and there are no best practice standards for how to incorporate ACP into PD care. This study describes patient and care partner perspectives on ACP to inform a patient- and care partner-centered framework for clinical care.

METHODS

This is a qualitative descriptive study of 30 patients with PD and 30 care partners within a multisite, randomized clinical trial of neuropalliative care compared to standard care. Participants were individually interviewed about perspectives on ACP, including prior and current experiences, barriers to ACP, and suggestions for integration into care. Interviews were analyzed using theme analysis to identify key themes.

RESULTS

Four themes illustrate how patients and care partners perceive ACP as part of clinical care: (1) personal definitions of ACP vary in the context of PD; (2) patient, relationship, and health care system barriers exist to engaging in ACP; (3) care partners play an active role in ACP; (4) a palliative care approach positively influences ACP. Taken together, the themes support clinician initiation of ACP discussions and interdisciplinary approaches to help patients and care partners overcome barriers to ACP.

CONCLUSIONS

ACP in PD may be influenced by patient and care partner perceptions and misperceptions, symptoms of PD (e.g., apathy, cognitive dysfunction, disease severity), and models of clinical care. Optimal engagement of patients with PD and care partners in ACP should proactively address misperceptions of ACP and utilize clinic teams and workflow routines to incorporate ACP into regular care.

Does outpatient palliative care improve patient-centered outcomes in Parkinson's disease: Rationale, design, and implementation of a pragmatic comparative effectiveness trial

Patients with Parkinson's disease and related disorders (PDRD) and their families have considerable unmet needs including non-motor symptom management, caregiver support, spiritual wellbeing, advance care planning, and end-of-life care. There is increasing interest in applying palliative care (PC) models to better meet these needs. While PC has been shown to improve care and quality of life (QOL) for people with cancer and heart failure, few studies have evaluated the role of PC for people with PDRD. Well-designed clinical trials are needed to optimize the PC approach for PDRD and to influence policy and implementation efforts. We initiated a randomized multicenter comparative effectiveness trial of team-based outpatient PC versus usual care for people with PDRD and their caregivers. The primary aims of this study are to determine the effects of PC on patient QOL and caregiver burden. Qualitative interviews will be utilized to gain additional insights into the impact of PC on participants, the outcomes that matter most to this population, and to find opportunities to refine future interventions and trials. As a novel application of PC, challenges involved in the design of this study include choosing appropriate inclusion criteria, standardizing the intervention, defining usual care, and choosing outcome measures suitable to our research questions. Challenges involved in implementation include participant recruitment, retention, and management of participant burden. We anticipate the results of this trial will have relevance for both clinical care and future clinical research trial design in evaluating models of PC for people with PDRD and other serious illnesses.

How Well Do Caregivers Detect Depression and Anxiety in Patients With Parkinson Disease?

Depression and anxiety are prevalent in Parkinson disease (PD) yet underrecognized in clinical practice. Caregiver reports are frequently utilized to aid in the assessment of neuropsychiatric symptoms but little is known about caregivers' ability to recognize them in patients with PD. This study sought to examine the accuracy of caregiver reports. Eighty patient-caregiver dyads were involved. Accuracy of caregiver recognition was assessed by examining the level of agreement between caregiver ratings on the Neuropsychiatric Inventory and patients' diagnosis of depression and anxiety on the Mini-International Neuropsychiatric Interview (MINI)-Plus. The agreement between caregiver report and MINI-Plus diagnosis was low for both depression (6.3%) and anxiety (17.5%). The presence of depression was overreported, while anxiety was largely underestimated by caregivers. Caregiver distress significantly predicted inaccurate caregiver identification of depression ( R² = .51, P < .001) and anxiety ( R² = .08, P < .05). Results indicate that caregivers may be poor at recognizing depression and anxiety in patients with PD. Utilization of caregiver report should take into account potential biases that affect caregiver judgment.

Low-fat versus ketogenic diet in Parkinson's disease: A pilot randomized controlled trial

Background: Preliminary evidence suggests that diet manipulation may influence motor and nonmotor symptoms in PD, but conflict exists regarding the ideal fat to carbohydrate ratio.

Objectives: We designed a pilot randomized, controlled trial to compare the plausibility, safety, and efficacy of a low‐fat, high‐carbohydrate diet versus a ketogenic diet in a hospital clinic of PD patients.

Methods: We developed a protocol to support PD patients in a diet study and randomly assigned patients to a low‐fat or ketogenic diet. Primary outcomes were within‐ and between‐group changes in MDS‐UPDRS Parts 1 to 4 over 8 weeks.

Results: We randomized 47 patients, of which 44 commenced the diets and 38 completed the study (86% completion rate for patients commencing the diets). The ketogenic diet group maintained physiological ketosis. Both groups significantly decreased their MDS‐UPDRS scores, but the ketogenic group decreased more in Part 1 (−4.58 ± 2.17 points, representing a 41% improvement in baseline Part 1 scores) compared to the low‐fat group (−0.99 ± 3.63 points, representing an 11% improvement) (P < 0.001), with the largest between‐group decreases observed for urinary problems, pain and other sensations, fatigue, daytime sleepiness, and cognitive impairment. There were no between‐group differences in the magnitude of decrease for Parts 2 to 4. The most common adverse effects were excessive hunger in the low‐fat group and intermittent exacerbation of the PD tremor and/or rigidity in the ketogenic group.

Conclusions: It is plausible and safe for PD patients to maintain a low‐fat or ketogenic diet for 8 weeks. Both diet groups significantly improved in motor and nonmotor symptoms; however, the ketogenic group showed greater improvements in nonmotor symptoms. © 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Educational Needs and Considerations for a Visual Educational Tool to Discuss Parkinson's Disease

Background

In our clinical experience, people with Parkinson's disease (PwP) and their caregivers have difficulty understanding the complexities of the disease, which has a multitude of symptoms and involved therapies. We undertook a needs assessment to understand the need for, and to guide the development of, an educational tool.

Methods

We invited PwP, caregivers and health care providers (HCP) from across Canada to participate in an online survey to determine the need and desired content for such a tool.

Results

Respondents included 450 PwP, 335 caregivers, and 96 HCP from across Canada. 86.5% of HCP reported that it was "very important" for patients to understand issues in PD and 84.4% would use a visual aid to explain these issues. Results showed that 81.9-95.7% of caregivers and PwP were not "very satisfied" with the explanations of all domains in PD. Non-motor symptoms and cognitive issues were highly ranked by all groups as difficult to understand or explain. Older PwP (those with PD for less than 5 years and those who reported that their HCP spent less than 15 minutes counselling in each clinic visit) were less likely to fully understand and be satisfied with the explanations of most issues in PD.

Interpretation

There is a need for better patient education when discussing PD issues in the clinical setting. Older PwP that have been recently diagnosed have the greatest educational needs. Potential users indicate that a visual aid would help and non-motor symptoms, particularly cognitive issues, need to be a focus of such a tool.

A systematic review of the literature on disorders of sleep and wakefulness in Parkinson's disease from 2005 to 2015

Sleep disorders are among the most common non-motor manifestations in Parkinson's disease (PD) and have a significant negative impact on quality of life. While sleep disorders in PD share most characteristics with those that occur in the general population, there are several considerations specific to this patient population regarding diagnosis, management, and implications. The available research on these disorders is expanding rapidly, but many questions remain unanswered. We thus conducted a systematic review of the literature published from 2005 to 2015 on the following disorders of sleep and wakefulness in PD: REM sleep behavior disorder, insomnia, nocturia, restless legs syndrome and periodic limb movements, sleep disordered breathing, excessive daytime sleepiness, and circadian rhythm disorders. We discuss the epidemiology, etiology, clinical implications, associated features, evaluation measures, and management of these disorders. The influence on sleep of medications used in the treatment of motor and non-motor symptoms of PD is detailed. Additionally, we suggest areas in need of further research.

Cognitive impairment in patients with Parkinson's disease: A 30-month follow-up study

OBJECTIVE

A longitudinal (30-month) study of the cognitive changes in Parkinson's disease patients and analysis of influencing factors.

METHODS

The cognitive function and related symptoms of 102 patients with idiopathic Parkinson's disease were assessed using the Montreal Cognitive Assessment (MoCA), Mini-Mental State Examination (MMSE), and relevant scales, at baseline and 30-month follow-up. The t-test, nonparametric tests, and regression analyses were used to evaluate cognitive decline and investigate risk factors for cognitive impairment.

RESULTS

From baseline to follow-up, the MMSE and MoCA scores significantly decreased, respectively, from 28.16±2.29 to 26.18±3.64, and from 24.60±4.23 to 21.94±5.47 (both P<0.001). Impairment was observed in multiple cognitive areas, significantly in naming, delayed recall, and orientation (P<0.01). Patients at baseline with postural instability and gait disturbance (PIGD), lower MoCA scores, or depression had a higher risk of cognitive impairment at follow-up (P<0.01).

CONCLUSION

Cognitive impairment is highly prevalent in Parkinson's disease patients, especially for those with lower MoCA scores, PIGD, and depression.

Delineating nonmotor symptoms in early Parkinson's disease and first-degree relatives

Nonmotor symptoms (NMS) are an important prodromal feature of Parkinson's disease (PD). However, their frequency, treatment rates, and impact on health‐related quality of life (HRQoL) in the early motor phase is unclear. Rates of NMS in enriched at‐risk populations, such as first‐degree PD relatives, have not been delineated. We assessed NMS in an early cohort of PD, first‐degree PD relatives and control subjects to address these questions. In total, 769 population‐ascertained PD subjects within 3.5 years of diagnosis, 98 first‐degree PD relatives, and 287 control subjects were assessed at baseline across the following NMS domains: (1) neuropsychiatric; (2) gastrointestinal; (3) sleep; (4) sensory; (5) autonomic; and (6) sexual. NMS were much more common in PD, compared to control subjects. More than half of the PD cases had hyposmia, pain, fatigue, sleep disturbance, or urinary dysfunction. NMS were more frequent in those with the postural instability gait difficulty phenotype, compared to the tremor dominant (mean total number of NMS 7.8 vs. 6.2; P < 0.001). PD cases had worse HRQoL scores than controls (odds ratio: 4.1; P < 0.001), with depression, anxiety, and pain being stronger drivers than motor scores. NMS were rarely treated in routine clinical practice. First‐degree PD relatives did not significantly differ in NMS, compared to controls, in this baseline study. NMS are common in early PD and more common in those with postural instability gait difficulty phenotype or on treatment. Despite their major impact on quality of life, NMS are usually under‐recognized and untreated. © 2015 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

The clinical spectrum of anxiety in Parkinson's disease

Anxiety is common in Parkinson's disease (PD), and contributes to increased disability and poorer quality of life. In spite of its significant impact, the symptomatology, chronology, and neurobiology of anxiety in PD are all poorly understood, and this hinders accurate diagnosis and development of effective treatment strategies. This review investigates and updates literature related to the clinical spectrum of anxiety in PD. The reported prevalence of anxiety in PD varies considerably, with emerging interest in the frequency of the DSM-IV residual category of "Anxiety disorder, not otherwise specified" (Anxiety disorder NOS), which is observed in up to 25% of PD patients. By design, there are no standardized diagnostic criteria for Anxiety disorder NOS, because this is the category applied to individuals who do not meet diagnostic criteria for any other current anxiety disorder. Anxiety rating scales incompletely capture anxiety symptoms that relate specifically to PD symptoms and the complications arising from PD therapy. Consequently, these scales have been deemed inappropriate for use in PD, and there remains a need for the development of a new PD-specific anxiety scale. Research establishing accurate symptom profiles of anxiety in PD is sparse, although characterizing such symptomatology would likely improve clinical diagnosis and facilitate targeted treatment strategies. Research into the neurobiological and psychological underpinnings of anxiety in PD remains inconclusive. Anxiety can precede the onset of PD motor symptoms or can develop after a diagnosis of PD. Further investigations focused on the chronology of anxiety and its relationship to PD diagnosis are required.

Is Dysregulation of the HPA-Axis a Core Pathophysiology Mediating Co-Morbid Depression in Neurodegenerative Diseases?

There is increasing evidence of prodromal manifestation of neuropsychiatric symptoms in a variety of neurodegenerative diseases such as Parkinson's disease (PD) and Huntington's disease (HD). These affective symptoms may be observed many years before the core diagnostic symptoms of the neurological condition. It is becoming more apparent that depression is a significant modifying factor of the trajectory of disease progression and even treatment outcomes. It is therefore crucial that we understand the potential pathophysiologies related to the primary condition, which could contribute to the development of depression. The hypothalamic-pituitary-adrenal (HPA)-axis is a key neuroendocrine signaling system involved in physiological homeostasis and stress response. Disturbances of this system lead to severe hormonal imbalances, and the majority of such patients also present with behavioral deficits and/or mood disorders. Dysregulation of the HPA-axis is also strongly implicated in the pathology of major depressive disorder. Consistent with this, antidepressant drugs, such as the selective serotonin reuptake inhibitors have been shown to alter HPA-axis activity. In this review, we will summarize the current state of knowledge regarding HPA-axis pathology in Alzheimer's, PD and HD, differentiating between prodromal and later stages of disease progression when evidence is available. Both clinical and preclinical evidence will be examined, but we highlight animal model studies as being particularly useful for uncovering novel mechanisms of pathology related to co-morbid mood disorders. Finally, we purpose utilizing the preclinical evidence to better inform prospective, intervention studies.

Effects of the adenosine A2A receptor antagonist on cognitive dysfunction in Parkinson's disease

Parkinson's disease (PD) is primarily characterized by motor abnormalities, but cognitive changes also occur in the early and late stages of the disease process. In PD patients, cognitive dysfunction is associated with reduced quality of life, as well as increased morbidity and mortality, resulting in increases in caregiver burden, and health-related costs. Therefore, safe and effective approaches are needed to treat cognitive dysfunction in PD patients. The underlying pathophysiology of cognitive dysfunction is complex and not fully understood, however. α-Synuclein, amyloid-related proteins, and cholinergic deficits have been reported to partially contribute to cognitive dysfunction. Changes in cortical dopamine (DA) content may also be responsible for early cognitive changes in patients with PD. Certainly, dopaminergic afferents to the frontal cortex degenerate in PD, and there is a reduction of DA content in the prefrontal cortex (PFC). It has also been reported that PFC dopaminergic input plays an important role in working memory performance. Moreover, PFC DA levels and working memory performance are significantly reduced by a 6-hydroxydopamine lesion in the PFC of a rat. Recent findings in the areas of pharmacological manipulation and genetic ablation suggest that the adenosine A2A receptor is also related to cognitive functions, especially working memory. In addition, the blockade of adenosine A2A receptors reverses cognitive dysfunction in PFC-lesioned rats, and this blocking effect may be due to an increase in PFC DA content. Therefore, adenosine A2A receptor antagonists not only improve motor performance, but they may also lead to improved cognitive function in those with PD.

Cognitive impairment in patients with Parkinson's disease: diagnosis, biomarkers, and treatment

Dementia is one of the most common and important aspects of Parkinson's disease and has consequences for patients and caregivers, and has health-related costs. Mild cognitive impairment is also common and frequently progresses to dementia. The underlying mechanisms of dementia associated with Parkinson's disease are only partly known and no mechanism-based treatments are available. Both dysmetabolism of α-synuclein and amyloid-protein and cholinergic deficits contribute to cognitive impairment in Parkinson's disease, and preliminary findings show that imaging and neurophysiological and peripheral biomarkers could be useful in diagnosis and prognosis. Rivastigmine is the only licensed treatment for dementia in Parkinson's disease, but emerging evidence suggests that memantine might also be useful. Whether these or other treatments can delay the progression from mild cognitive impairment to dementia in Parkinson's disease is a key research question.