Parkinson's disease: the quintessential neuropsychiatric disorder

Neurobiology and clinical features of impulse control failure in Parkinson's disease

Impulse control disorders (ICDs) and other impulsive-compulsive related behaviours are frequent and still under recognized non-motor complications of Parkinson's disease (PD). They result from sensitization of the mesocorticolimbic pathway that arose in predisposed PD patients concomitantly with spreading of PD pathology, non-physiological dopaminergic and pulsatile administration of dopamine replacement therapy (DRT). Neuropsychiatric fluctuations (NPF) reflect the psychotropic effects of dopaminergic drugs and play a crucial role in the emergence of ICDs and behavioral addictions. Dopamine agonists (DA) which selectively target D2 and D3 receptors mostly expressed within the mesocorticolimbic pathway, are the main risk factor to develop ICDs. Neuroimaging studies suggest that dopamine agonists lead to a blunted response of the brain's reward system both during reward delivery and anticipation. Genetic predispositions are crucial for the responsiveness of the mesolimbic system and the development of ICDs with several genes having been identified. Early screening for neuropsychiatric fluctuations, reduction of DA, fractionating levodopa dosage, education of patients and their relatives, are the key strategies for diagnosis and management of ICDs and related disorders.

Behavioural outcomes of subthalamic stimulation and medical therapy versus medical therapy alone for Parkinson's disease with early motor complications (EARLYSTIM trial): secondary analysis of an open-label randomised trial

BACKGROUND

Although subthalamic stimulation is a recognised treatment for motor complications in Parkinson's disease, reports on behavioural outcomes are controversial, which represents a major challenge when counselling candidates for subthalamic stimulation. We aimed to assess changes in behaviour in patients with Parkinson's disease receiving combined treatment with subthalamic stimulation and medical therapy over a 2-year follow-up period as compared with the behavioural evolution under medical therapy alone.

METHODS

We did a parallel, open-label study (EARLYSTIM) at 17 surgical centres in France (n=8) and Germany (n=9). We recruited patients with Parkinson's disease who were disabled by early motor complications. Participants were randomly allocated (1:1) to either medical therapy alone or bilateral subthalamic stimulation plus medical therapy. The primary outcome was mean change in quality of life from baseline to 2 years. A secondary analysis was also done to assess behavioural outcomes. We used the Ardouin Scale of Behavior in Parkinson's Disease to assess changes in behaviour between baseline and 2-year follow-up. Apathy was also measured using the Starkstein Apathy Scale, and depression was assessed with the Beck Depression Inventory. The secondary analysis was done in all patients recruited. We used a generalised estimating equations (GEE) regression model for individual items and mixed model regression for subscores of the Ardouin scale and the apathy and depression scales. This trial is registered with ClinicalTrials.gov, number NCT00354133. The primary analysis has been reported elsewhere; this report presents the secondary analysis only.

FINDINGS

Between July, 2006, and November, 2009, 251 participants were recruited, of whom 127 were allocated medical therapy alone and 124 were assigned bilateral subthalamic stimulation plus medical therapy. At 2-year follow-up, the levodopa-equivalent dose was reduced by 39% (-363·3 mg/day [SE 41·8]) in individuals allocated bilateral subthalamic stimulation plus medical therapy and was increased by 21% (245·8 mg/day [40·4]) in those assigned medical therapy alone (p<0·0001). Neuropsychiatric fluctuations decreased with bilateral subthalamic stimulation plus medical therapy during 2-year follow-up (mean change -0·65 points [SE 0·15]) and did not change with medical therapy alone (-0·02 points [0·15]); the between-group difference in change from baseline was significant (p=0·0028). At 2 years, the Ardouin scale subscore for hyperdopaminergic behavioural disorders had decreased with bilateral subthalamic stimulation plus medical therapy (mean change -1·26 points [SE 0·35]) and had increased with medical therapy alone (1·12 points [0·35]); the between-group difference was significant (p<0·0001). Mean change from baseline at 2 years in the Ardouin scale subscore for hypodopaminergic behavioural disorders, the Starkstein Apathy Scale score, and the Beck Depression Inventory score did not differ between treatment groups. Antidepressants were stopped in 12 patients assigned bilateral subthalamic stimulation plus medical therapy versus four patients allocated medical therapy alone. Neuroleptics were started in nine patients assigned medical therapy alone versus one patient allocated bilateral subthalamic stimulation plus medical therapy. During the 2-year follow-up, two individuals assigned bilateral subthalamic stimulation plus medical therapy and one patient allocated medical therapy alone died by suicide.

INTERPRETATION

In a large cohort with Parkinson's disease and early motor complications, better overall behavioural outcomes were noted with bilateral subthalamic stimulation plus medical therapy compared with medical therapy alone. The presence of hyperdopaminergic behaviours and neuropsychiatric fluctuations can be judged additional arguments in favour of subthalamic stimulation if surgery is considered for disabling motor complications.

FUNDING

German Federal Ministry of Education and Research, French Programme Hospitalier de Recherche Clinique National, and Medtronic.

Improved understanding, detection, and management of neuropsychiatric complications: essential components to the optimal treatment of Parkinson's disease

It has been well established that Parkinson's disease (PD) is not just a movement disorder (Weintraub and Burn, 2011). Fortunately, the past two decades have seen increased attention to the neuropsychiatric aspects of the disease process. Neuropsychiatric symptoms (e.g., mood, sleep, psychosis, and impulse control) are experienced by the overwhelming majority of people living with PD (PWP) and have a detrimental impact on physical and cognitive decline (Pontone et al., 2016), quality of life (van Uem et al., 2016), and caregiving relationships (Santos-García, 2015). As a field, all multidisciplinary providers involved in the care of PWP, inclusive of movement disorder specialists, geriatric psychiatrists, clinical psychologists, social workers, and other allied healthcare providers, must work to improve the recognition and treatment of key non-motor symptoms, such as depression and anxiety, as part of the standard of care (Cohen et al., 2016). Improved detection and management is critical, as the failure to appropriately treat psychiatric complications negatively impacts the overall course of the illness, functional aspects of daily life, and the PWP ability to fully engage in their own self-care (Pontone et al., 2016).

Episodic recognition memory and the hippocampus in Parkinson's disease: A review

Parkinson's disease is a progressive neurodegenerative disorder of aging. The hallmark pathophysiology includes the development of neuronal Lewy bodies in the substantia nigra of the midbrain with subsequent loss of dopaminergic neurons. These neuronal losses lead to the characteristic motor symptoms of bradykinesia, rigidity, and rest tremor. In addition to these cardinal motor symptoms patients with PD experience a wide range of non-motor symptoms, the most important being cognitive impairments that in many circumstances lead to dementia. People with PD experience a wide range of cognitive impairments; in this review we will focus on memory impairment in PD and specifically episodic memory, which are memories of day-to-day events of life. Importantly, these memory impairments severely impact the lives of patients and caregivers alike. Traditionally episodic memory is considered to be markedly dependent on the hippocampus; therefore, it is important to understand the exact nature of PD episodic memory deficits in relation to hippocampal function and dysfunction. In this review, we discuss an aspect of episodic memory called recognition memory and its subcomponents called recollection and familiarity. Recognition memory is believed to be impaired in PD; thus, we discuss what aspects of the hippocampus are expected to be deficient in function as they relate to these recognition memory impairments. In addition to the hippocampus as a whole, we will discuss the role of hippocampal subfields in recognition memory impairments.

Effect of Parkinsonism on Proximal Unstructured Movement Captured by Inertial Sensors

In this study, we endeavour to measure characteristic movements of patients with Parkinson's disease (PD). Our eventual aim is to obtain the severity of these exhibited movements entirely based on measurements conducted in un-clinical environments. Indeed, we investigate the feasibility of capturing such un-structured movements using wearable sensors. In particular, as Bradykinesia and axial Bradykinesia are vital characteristics yet challenging to measure, we design a test system of Inertial Measurement (IM) based wearable sensors in order to capture the affected movements of the back. The study evaluated the characteristics of PD patients during the unstructured activities. Our analysis captured back flexibility based on frequency information of the sensors attached to the human back. Satisfactory classification in each test confirms that this testing system can identify as well as evaluate PD patients using a minimal number of sensors during these unstructured movements. Our objective is to enhance the uptake and promote the use of wearable sensors in longer term monitoring scenarios relevant to non-clinical environments. Thus, we envisage clinicians monitoring the progress due to the treatment of patients residing in their homes assisted by sensors with enhanced wearability.

Informant- and Self-Appraisals on the Psychosis and Hallucinations Questionnaire (PsycH-Q) Enhances Detection of Visual Hallucinations in Parkinson's Disease

Background

Clinicians vary in their ability to elicit and interpret hallucinatory symptoms in patients with Parkinson's disease (PD). There is limited evidence for informant-report measures of PD hallucinations as adjuncts to clinician-rated scales.

Objectives

To determine the utility of an informant version of the validated Psychosis and Hallucinations Questionnaire (PsycH-Q) for assessing the presence and severity of hallucinations in PD; and, to evaluate accuracy of clinician judgements by comparison with informant report and self-report.

Methods

One hundred sixty-three PD patient-informant dyads completed self- and informant-report versions of PsycH-Q and three common questionnaire measures: Neuropsychiatric Inventory Questionnaire; Parkinson's Psychosis Questionnaire; and Scales for Outcomes in Parkinson's disease-Psychiatric Complications. We compared self-ratings and informant ratings across analogous subscales for the presence of hallucinations with clinician interview ratings on MDS-UPDRS as a diagnostic standard.

Results

There was a low level of agreement between dyads (average κ = 0.39; κ range = 0.32-0.47; P < 0.001), and patients indicated the highest prevalence of hallucinations compared to informant or clinician estimates. Clinician interview missed 32% of PsycH-Q hallucinators identified by dyads. Relative to the sample, 22 patients with exclusively clinician-appraised hallucinations had poorer overall quality of life measured by the Parkinson's Disease Questionnaire.

Conclusions

The sole use of clinician-rated scales may underestimate prevalence of PD hallucinations, and there is room for introducing self- and informant-report tools. Nonetheless, clinician appraisals are critical in cases when informant and patient insight might be affected by the impact of illness on quality of life.

Validation of a performance-based assessment of cognitive functional ability in Parkinson's disease

BACKGROUND

Outcome measures that capture functional abilities related to cognition offer the potential to demonstrate real-world effectiveness of cognitive-enhancing treatments. However, distinguishing functional disability related to cognition from that attributed to motor symptoms can be difficult in PD. A performance-based functional assessment allows for direct observation of activity of daily living skills and separation of cognitive from motoric disabilities.

OBJECTIVES

Validate the University of California San Diego Performance-Based Skills Assessment in PD.

METHODS

One hundred PD participants, ranging from normal cognition to dementia, completed the University of California San Diego Performance-Based Skills Assessment, a performance-based measure of cognitively demanding activities of daily living, as well as a neuropsychological battery and motor examination. Cognitive classification was determined by consensus conference, blinded to University of California San Diego Performance-Based Skills Assessment scores. Psychometric properties of the University of California San Diego Performance-Based Skills Assessment, including internal consistency, test-retest and inter-rater reliability, and discriminant validity for dementia, were examined.

RESULTS

The University of California San Diego Performance-Based Skills Assessment demonstrated strong internal consistency (Cronbach's α = 0.82) and test-retest reliability (r = 0.89) and correlated strongly with global cognition (Mattis Dementia Rating Scale: r = 0.80; P < 0.001). University of California San Diego Performance-Based Skills Assessment regression models indicated greater contribution from cognitive explanatory variables (marginal partial: R2  = 0.33) than motor variables (marginal partial: R2  = 0.05), controlling for age, education, disease duration, and l-dopa equivalent dose. Additionally, the University of California San Diego Performance-Based Skills Assessment exhibited strong discriminant validity for dementia (area under the curve = 0.91).

CONCLUSIONS

The University of California San Diego Performance-Based Skills Assessment is a valid measure of functional abilities related to cognition rather than motor symptoms in PD. Furthermore, it reliably distinguishes demented from nondemented participants. The University of California San Diego Performance-Based Skills Assessment may be considered as an outcome measure that combines cognitive and functional abilities in treatment trials for cognitive impairment in PD. © 2018 International Parkinson and Movement Disorder Society.

Amyloid-β and Parkinson's disease

Parkinson's disease (PD) is the second commonest neurodegenerative disorder in the world with a rising prevalence. The pathophysiology is multifactorial but aggregation of misfolded α-synuclein is considered to be a key underpinning mechanism. Amyloid-β (Aβ) and tau deposition are also comorbid associations and especially Aβ deposition is associated with cognitive decline in PD. Some existing evidence suggests that low cerebrospinal fluid (CSF) Aβ₄₂ is predictive of future cognitive impairment in PD. Recent studies also show that CSF Aβ is associated with the postural instability and gait difficulties (PIGD) or the newly proposed cholinergic subtype of PD, a possible risk factor for cognitive decline in PD. The glial-lymphatic system, responsible for convective solute clearance driven by active fluid transport through aquaporin-4 water channels, may be implicated in brain amyloid deposition. A better understanding of the role of this system and more specifically the role of Aβ in PD symptomatology, could introduce new treatment and repurposing drug-based strategies. For instance, apomorphine infusion has been shown to promote the degradation of Aβ in rodent models. This is further supported in a post-mortem study in PD patients although clinical implications are unclear. In this review, we address the clinical implication of cerebral Aβ deposition in PD and elaborate on its metabolism, its role in cognition and motor function/gait, and finally assess the potential effect of apomorphine on Aβ deposition in PD.

Fatigue in Parkinson's disease: A systematic review and meta-analysis

We conducted a systematic review and meta-analysis aimed at establishing robust prevalence estimates and identifying clinical correlates of fatigue in PD. From 2,459 titles and abstracts, we selected 44 relevant studies (n = 7427 patients). Overall, the meta-analysis showed a prevalence of fatigue of 50% in PD. This prevalence estimate, however, was significantly moderated by study heterogeneity in measurement scales and cut-off thresholds. In contrast, demographic features, disease severity, cognitive impairment, and depression did not moderate prevalence estimates. Moreover, fatigue prevalence did not differ between de novo and treated PD patients. Compared to nonfatigued patients, fatigued patients had sligthly higher age (1.44 years), disease duration (0.93 years), l-dopa equivalent daily dose (50.89 units), UPDRS-III (4.99 points), and H & Y (0.33 points), as well as risk of comorbid depression (risk ratio = 1.89) and had a little lower MMSE score (-0.66 points). Fatigue was moderately associated with apathy (Hedges' g = 0.55), anxiety (Hedges' g = 0.67), daytime somnolence (Hedges' g = 0.43), sleep disturbances (Hedges' g = 0.66), and poorer quality of life (Hedges' g = 1.23). Our analyses suggest that fatigue is a frequent, independent nonmotor symptom in PD appearing early and persisting throughout the disease course, and that establishing uniform diagnostic criteria for PD-related fatigue is critical. In addition, several nonmotor symptoms appear to be associated with fatigue and negatively impact quality of life. Pharmacological and nonpharmacological interventions targeting fatigue and associated symptoms may improve quality of life in patients with PD. © 2018 International Parkinson and Movement Disorder Society.

Insights on the age dependent neurodegeneration induced by Monocrotophos, (an organophosphorous insecticide) in Caenorhabditis elegans fed high glucose: Evidence in wild and transgenic strains

The higher susceptibility of high glucose fed C. elegans to Monocrotophos (MCP, an organophosphorus insecticide) - induced dopaminergic (DA) neuronal degeneration was recently demonstrated. Employing this acute exposure model, the impact of MCP on DA degeneration among worms of two age groups (8 and 13 d old) fed control (CO) and high glucose (GF) diet with specific focus on phenotypic alterations, oxidative impairments and associated molecular perturbations employing both wild (N2) and transgenic strains(BZ555 and NL5901) was investigated. In general, 13 d worms exhibited higher susceptibility to MCP intoxication compared to 8 d old worms. Further, MCP-exposure caused an enhanced degree of DA degeneration among glucose fed (GF) worms as evidenced by lower chemotaxis index, reduced long-term memory and increased nonanone repulsion. Biochemical analysis of 13 d GF worms also revealed a significant increase in ROS, protein carbonyls and reduced ADP/ATP ratio. Interestingly, marked increase in degeneration of dopaminergic neurons and increased in α-synuclein content was evident among 13 d GF worms exposed to MCP. Significant alterations in the mRNA expression levels of daf-2, age-1, sir 2.1 and aak-2 among 13 d GF worms was evident. Collectively these findings suggest that high intake of glucose diet aggravates MCP associated dopaminergic neuronal degeneration and the impact of increasing age under such a condition. Moreover it provides an experimental paradigm to explore the molecular targets and mechanism/s underlying the possible relationship between insecticide exposure-associated dopaminergic degeneration in humans under hyperglycemic conditions.

Subthalamic stimulation and neuropsychiatric symptoms in Parkinson's disease: results from a long-term follow-up cohort study

BACKGROUND

Reports on behavioural outcomes after subthalamic nucleus deep brain stimulation in Parkinson's disease are controversial and limited to short-term data. Long-term observation in a large cohort allows a better counselling and management.

METHODS

To determine whether a long-term treatment with subthalamic stimulation induces or reduces impulse control behaviours, neuropsychiatric fluctuations and apathy, 69 patients treated with subthalamic stimulation are prospectively and retrospectively assessed using Ardouin Scale of Behavior in Parkinson's Disease before and after 3-10 years of stimulation.

RESULTS

At a mean follow-up of 6 years, all impulse control disorders and dopaminergic addiction were significantly decreased, apart from eating behaviour and hypersexuality. Neuropsychiatric fluctuations also significantly improved (ON euphoria: 38% of the patients before surgery and 1% after surgery, P<0.01; OFF dysphoria: 39% of the patients before surgery and 10% after surgery, P<0.01). However, apathy increased (25% of the patients after surgery and 3% before, P<0.01). With the retrospective analysis, several transient episodes of depression, apathy, anxiety and impulse control disorders occurred.

CONCLUSIONS

Bilateral subthalamic nucleus stimulation was overall very effective in improving impulse control disorders and neuropsychiatric fluctuations in parkinsonian patients in the long term despite a counteracting frequent apathy. Transient episodes of impulse control disorders still occurred within the follow-up. These findings recommend a close follow-up in parkinsonian patients presenting with neuropsychiatric symptoms before deep brain stimulation surgery.

CLINICAL TRIAL REGISTRATION

NCT01705418;Post-results.

Understandings of psychological difficulties in people with the Huntington's disease gene and their expectations of psychological therapy

OBJECTIVES

This study sought to investigate how people who had tested positive for the Huntington's disease (HD) gene mutation understood and experienced psychological distress and their expectations of psychological therapy.

DESIGN

A qualitative methodology was adopted involving semi-structured interviews and interpretative phenomenological analysis (IPA).

METHOD

A total of nine participants (five women and four men) who had opted to engage in psychological therapy were recruited and interviewed prior to the start of this particular psychological therapeutic intervention. Interviews were transcribed verbatim and analysed using IPA whereby themes were analysed within and across transcripts and classified into superordinate themes.

RESULTS

Three superordinate themes were developed: Attributing psychological distress to HD: 'you're blaming everything on that now'; Changes in attributions of distress over time: 'in the past you'd just get on with it'; and Approaching therapy with an open mind, commitment, and hope: 'a light at the end of the tunnel'.

CONCLUSION

Understandings of psychological distress in HD included biological and psychological explanations, with both often being accepted simultaneously by the same individual but with biomedical accounts generally dominating. Individual experience seemed to reflect a dynamic process whereby people's understanding and experience of their distress changed over time. Psychological therapy was accepted as a positive alternative to medication, providing people with HD with hope that their psychological well-being could be enhanced.

PRACTITIONER POINTS

People with the Huntington's disease gene mutation have largely biomedical understandings of their psychological distress. This largely biomedical understanding does not, however, preclude them for being interested in the potential gains resulting from psychological therapy. The mechanisms of psychological therapy should be explained in detail before therapy and explored along with current attributions of distress.

Striatal changes in Parkinson disease: An investigation of morphology, functional connectivity and their relationship to clinical symptoms

We sought to investigate morphological and resting state functional connectivity changes to the striatal nuclei in Parkinson disease (PD) and examine whether changes were associated with measures of clinical function. Striatal nuclei were manually segmented on 3T-T1 weighted MRI scans of 74 PD participants and 27 control subjects, quantitatively analysed for volume, shape and also functional connectivity using functional MRI data. Bilateral caudate nuclei and putamen volumes were significantly reduced in the PD cohort compared to controls. When looking at left and right hemispheres, the PD cohort had significantly smaller left caudate nucleus and right putamen volumes compared to controls. A significant correlation was found between greater atrophy of the caudate nucleus and poorer cognitive function, and between greater atrophy of the putamen and more severe motor symptoms. Resting-state functional MRI analysis revealed altered functional connectivity of the striatal structures in the PD group. This research demonstrates that PD involves atrophic changes to the caudate nucleus and putamen that are linked to clinical dysfunction. Our work reveals important information about a key structure-function relationship in the brain and provides support for caudate nucleus and putamen atrophy as neuroimaging biomeasures in PD.

Basal ganglia and beyond: The interplay between motor and cognitive aspects in Parkinson's disease rehabilitation

Parkinson's disease (PD) is characterized by motor and cognitive dysfunctions, affecting the motor behaviour. We summarize evidence that the interplay between motor and cognitive approaches is crucial in PD rehabilitation. Rehabilitation is complementary to pharmacological therapy and effective in reducing the PD disturbances, probably acting by inducing neuroplastic effects. The motor behaviour results from a complex integration between cortical and subcortical areas, underlying the motor, cognitive and motivational aspects of movement. The close interplay amongst these areas makes possible to learn, control and express habitual-automatic actions, which are dysfunctional in PD. The physiopathology of PD could be considered the base for the development of effective rehabilitation treatments. As the volitional action control is spared in early-medium stages of disease, rehabilitative approaches engaging cognition permit to achieve motor benefits and appear to be the most effective for PD. We will point out data supporting the relevance of targeting both motor and cognitive aspects in PD rehabilitation. Finally, we will discuss the role of cognitive engagement in motor rehabilitation for PD.

Goal-orientated cognitive rehabilitation for dementias associated with Parkinson's disease-A pilot randomised controlled trial

OBJECTIVE

To examine the appropriateness and feasibility of cognitive rehabilitation for people with dementias associated with Parkinson's in a pilot randomised controlled study.

METHODS

This was a single-blind pilot randomised controlled trial of goal-oriented cognitive rehabilitation for dementias associated with Parkinson's. After goal setting, participants were randomised to cognitive rehabilitation (n = 10), relaxation therapy (n = 10), or treatment-as-usual (n = 9). Primary outcomes were ratings of goal attainment and satisfaction with goal attainment. Secondary outcomes included quality of life, mood, cognition, health status, everyday functioning, and carers' ratings of goal attainment and their own quality of life and stress levels. Assessments were at 2 and 6 months following randomisation.

RESULTS

At 2 months, cognitive rehabilitation was superior to treatment-as-usual and relaxation therapy for the primary outcomes of self-rated goal attainment (d = 1.63 and d = 1.82, respectively) and self-rated satisfaction with goal attainment (d = 2.04 and d = 1.84). At 6 months, cognitive rehabilitation remained superior to treatment-as-usual (d = 1.36) and relaxation therapy (d = 1.77) for self-rated goal attainment. Cognitive rehabilitation was superior to treatment as usual and/or relaxation therapy in a number of secondary outcomes at 2 months (mood, self-efficacy, social domain of quality of life, carers' ratings of participants' goal attainment) and at 6 months (delayed recall, health status, quality of life, carer ratings of participants' goal attainment). Carers receiving cognitive rehabilitation reported better quality of life, health status, and lower stress than those allocated to treatment-as-usual.

CONCLUSIONS

Cognitive rehabilitation is feasible and potentially effective for dementias associated with Parkinson's disease.

Caregiver burden and caregiver appraisal of psychiatric symptoms are not modulated by subthalamic deep brain stimulation for Parkinson's disease

Subthalamic deep brain stimulation is an advanced therapy that typically improves quality of life for persons with Parkinson’s disease (PD). However, the effect on caregiver burden is unclear. We recruited 64 persons with PD and their caregivers from a movement disorders clinic during the assessment of eligibility for subthalamic DBS. We used clinician-, patient- and caregiver-rated instruments to follow the patient–caregiver dyad from pre- to postoperative status, sampling repeatedly in the postoperative period to ascertain fluctuations in phenotypic variables. We employed multivariate models to identify key drivers of burden. We clustered caregiver-rated variables into ‘high’ and ‘low’ symptom groups and examined whether postoperative cluster assignment could be predicted from baseline values. Psychiatric symptoms in the postoperative period made a substantial contribution to longitudinal caregiver burden. The development of stimulation-dependent mood changes was also associated with increased burden. However, caregiver burden and caregiver-rated psychiatric symptom clusters were temporally stable and thus predicted only by their baseline values. We confirmed this finding using frequentist and Bayesian statistics, concluding that in our sample, subthalamic DBS for PD did not significantly influence caregiver burden or caregiver-rated psychiatric symptoms. Specifically, patient–caregiver dyads with high burden and high levels of psychiatric symptoms at baseline were likely to maintain this profile during follow-up. These findings support the importance of assessing caregiver burden prior to functional neurosurgery. Furthermore, they suggest that interventions addressing caregiver burden in this population should target those with greater symptomatology at baseline and may usefully prioritise psychiatric symptoms reported by the caregiver.

Using subthalamic deep brain stimulation (DBS) to treat patients with advanced Parkinson’s disease (PD) does not alleviate caregiver burden. Continuous electrical stimulation of deep brain nuclei has been shown to improve motor symptoms, reduce the need for dopaminergic medication and generally enhance patients’ quality of life. However, DBS can also produce psychiatric side effects, including depression and impulsivity potentially increasing the strain on caregivers. An Australian study led by Philip E. Mosley at Neurosciences Queensland followed the pre- and postoperative status of 64 patients and their caregivers for 26 weeks. They found that DBS did not influence caregiver burden nor caregiver-rated psychiatric symptoms. This study highlights the importance of assessing the well-being of caregivers prior to the patients’ surgery and the need to manage their expectations about the benefits of DBS treatment.

Objective measurement in routine care of people with Parkinson's disease improves outcomes

It is common in medicine to titrate therapy according to target ranges of objectively measured parameters. Objective measurement of motor function is available for Parkinson's Disease (PD), making it possible to optimise therapy and clinical outcomes. In this study, an accelerometry based measurement and predefined target ranges were used to assess motor function in a Northern Tasmania PD cohort managed by a Movement Disorder clinic. Approximately 40% (n = 103) of the total PD population participated in this study and motor scores were within target in 22%. In the 78% above target, changes in oral therapy were recommended in 74%, Advanced Therapy in 12% and treatment was contraindicated in 9%. Following changes in oral therapy, there was a further objective measurement and clinical consultation to establish whether scores had reached target range: if so subjects left the study, otherwise further changes of therapy were recommended (unless contraindications were present). Seventy-seven cases completed the study, with 48% achieving target (including 22% at outset), Advanced Therapy recommended in 19% and contraindications preventing any change in therapy in 17%. In the 43% of cases in whom oral therapy was changed, total UPDRS improved significantly (effect size = 8) as did the PDQ39 in cases reaching target. NMS Quest and MOCA scores also improved significantly. This study shows that many people in a representative cohort of PD would benefit from objective assessment and treatment of their PD features against a target.

Brain oscillations reveal impaired novelty detection from early stages of Parkinson's disease

The identification of reliable biomarkers for early diagnosis and progression tracking of neurodegenerative diseases has become an important objective in clinical neuroscience in the last years. The P3a event-related potential, considered as the neurophysiological hallmark of novelty detection, has been shown to be reduced in Parkinson's disease (PD) and proposed as a sensitive measure for illness duration and severity. Our aim for this study was to explore for the first time whether impaired novelty detection could be observed through phase- and time-locked brain oscillatory activity at early PD. Twenty-seven patients with idiopathic PD at early stages (disease duration <5 years and Hoehn and Yahr stage <3) were included. A healthy control group (n = 24) was included as well. All participants performed an auditory involuntary attention task including frequent and deviant tones while a digital EEG was obtained. A neuropsychological battery was administered as well. Time-frequency representations of power and phase-locked oscillations and P3a amplitudes were compared between groups. We found a significant reduction of power and phase locking of slow oscillations (3-7 Hz) for deviant tones in the PD group compared to controls in the P3a time range (300-550 ms). Also, reduced modulation of late induced (not phase locked) alpha-beta oscillations (400-650 ms, 8-25 Hz) was observed in the PD group after deviant tones onset. The P3a amplitude was predicted by years of evolution in the PD group. Finally, while phase-locked slow oscillations were associated with task behavioral distraction effects, induced alpha-beta activity was related to cognitive flexibility performance. Our results show that novelty detection impairment can be identified in neurophysiological terms from very early stages of PD, and such impairment increases linearly as the disease progresses. Also, induced alpha-beta oscillations underlying novelty detection are related to executive functioning.

The Subthalamic Nucleus: Unravelling New Roles and Mechanisms in the Control of Action

How do we decide what we do? This is the essence of action control, the process of selecting the most appropriate response among multiple possible choices. Suboptimal action control can involve a failure to initiate or adapt actions, or conversely it can involve making actions impulsively. There has been an increasing focus on the specific role of the subthalamic nucleus (STN) in action control. This has been fueled by the clinical relevance of this basal ganglia nucleus as a target for deep brain stimulation (DBS), primarily in Parkinson's disease but also in obsessive-compulsive disorder. The context of DBS has opened windows to study STN function in ways that link neuroscientific and clinical fields closely together, contributing to an exceptionally high level of two-way translation. In this review, we first outline the role of the STN in both motor and nonmotor action control, and then discuss how these functions might be implemented by neuronal activity in the STN. Gaining a better understanding of these topics will not only provide important insights into the neurophysiology of action control but also the pathophysiological mechanisms relevant for several brain disorders and their therapies.

The site of stimulation moderates neuropsychiatric symptoms after subthalamic deep brain stimulation for Parkinson's disease

Deep brain stimulation of the subthalamic nucleus for Parkinson's disease is an established advanced therapy that addresses motor symptoms and improves quality of life. However, it has also been associated with neuropsychiatric symptoms such as impulsivity and hypomania. When significant, these symptoms can be distressing, necessitating psychiatric intervention. However, a comprehensive analysis of neurocognitive and neuropsychiatric outcomes with reference to the site of subthalamic stimulation has not been undertaken. We examined this matter in a consecutive sample of 64 persons with Parkinson's disease undertaking subthalamic deep brain stimulation. Participants were assessed with a battery of neuropsychiatric instruments at baseline and at repeated postoperative intervals. A psychiatrist identified patients with emergent, clinically-significant symptoms due to stimulation. The site of the active electrode contact and a simulated volume of activated tissue were evaluated with reference to putative limbic, associative and motor subregions of the subthalamic nucleus. We studied anatomical correlates of longitudinal neuropsychiatric change and delineated specific subthalamic regions associated with neuropsychiatric impairment. We tested the ability of these data to predict clinically-significant symptoms. Subthalamic stimulation within the right associative subregion was associated with inhibitory errors on the Excluded Letter Fluency task at 6-weeks (p = 0.023) and 13-weeks postoperatively (p = 0.0017). A cluster of subthalamic voxels associated with inhibitory errors was identified in the right associative and motor subregions. At 6-weeks, clinically-significant neuropsychiatric symptoms were associated with the distance of the active contact to the right associative subregion (p = 0.0026) and stimulation within the right associative subregion (p = 0.0009). At 13-weeks, clinically-significant symptoms were associated with the distance to the right (p = 0.0027) and left (p = 0.0084) associative subregions and stimulation within the right associative subregion (p = 0.0026). Discrete clusters of subthalamic voxels associated with high and low likelihood of postoperative neuropsychiatric symptoms were identified in ventromedial and dorsolateral zones, respectively. When a classifier was trained on these data, clinically-significant symptoms were predicted with an accuracy of 79%. These data underscore the importance of accurate electrode targeting, contact selection and device programming to reduce postoperative neuropsychiatric impairment. The ability to predict neuropsychiatric symptoms based on subthalamic data may permit anticipation and prevention of these occurrences, improving safety and tolerability.

•

The site of subthalamic stimulation influences the emergence of neuropsychiatric symptoms.

•

Stimulation in the associative subthalamic subregion leads to disinhibition.

•

Psychiatrically ‘safe’ and ‘unsafe’ regions of the subthalamic nucleus can be identified.

•

Clinically-significant symptoms can be predicted by the site and distribution of stimulation.

•

Electrode placement and stimulation titration are key factors in the tolerability of this therapy.

Fatigue in Parkinson's disease: concepts and clinical approach

Parkinson's disease (PD) is a progressive neurological disorder characterized by a large number of motor and non-motor features. Fatigue is one of the most common and most disabling symptoms among patients with PD, and it has a significant impact on their quality of life. Although fatigue has been recognized for a long time, its pathophysiology remains poorly understood, and there is no evidence to support any therapeutic approach in PD patients. Expert consensus on case definition and diagnostic criteria for PD-related fatigue have been recently published, and although they still need to be adequately validated, they provide a great step forward in the study of fatigue. The goal of this article is to provide relevant information for the identification and management of patients with fatigue.

Pharmacological interventions for psychosis in Parkinson's disease patients

INTRODUCTION

Psychosis is a common problem for people treated for Parkinson's disease. The syndrome is quite stereotypic, with hallucinations being the most common, followed by delusions. While the hallucinations are usually not very bothersome, the delusions are typically paranoid in nature. Treatment is often, but not always, required.

AREAS COVERED

This article reviews the therapeutic approaches of this syndrome focusing on drug treatments used once contributory factors have been removed. This includes a review of the evidence supporting the use of clozapine and, most recently, pimavanserin, the first drug with antipsychotic efficacy that has no effect on dopamine. Treatment with second generation antipsychotic drugs and cholinesterase inhibitors are also reviewed.

EXPERT OPINION

Clozapine and pimavanserin have proven efficacy for Parkinson's disease psychosis (PDP), without impairing motor function. In clozapine's favor are its antipsychotic benefits seen within 1 week and its effectiveness in improving tremor in PD. However, this is counterbalanced by the need for blood monitoring, despite the extremely low doses used, and sedation. Pimanvanserin is well tolerated, without sedation or other significant side effects. Its onset of benefit, however takes 4-6 weeks. While quetiapine is also frequently used, its efficacy is not supported by double blinded, randomized trials.

Effects of dopaminergic depletion and brain atrophy on neuropsychiatric symptoms in de novo Parkinson's disease

BACKGROUND

Neuropsychiatric symptoms impact the patients' quality of life and caregivers' burdens in Parkinson's disease (PD). We aimed to investigate the effects of striatal dopaminergic depletion and brain atrophy on the neuropsychiatric symptoms of patients with PD.

METHODS

Two hundred and seven patients with de novo drug-naïve PD underwent dopamine transporter (DAT) positron emission tomography and brain MRI scanning. In addition, the patients were assessed with caregiver-administered neuropsychiatric inventory (NPI) questionnaires. To evaluate the effects of DAT uptake, subcortical volume and cortical thinning on the patients' neuropsychiatric symptoms, we performed logistic regression and negative binomial regression analyses on the NPI data after controlling for possible confounders.

RESULTS

Frontal cortical thinning was associated with the presence of nighttime behaviour and irritability, and the thinning correlated with the severity of the nighttime behaviour. Temporal cortical thinning was associated with the presence of aggression/agitation, and it correlated with the severity of the aggression/agitation. Subcortical atrophy in the accumbens was associated with the presence of disinhibition and correlated with the severity of the disinhibition. Putamen atrophy and insular thinning were independently associated with the presence of apathy, but only insular thinning correlated with the severity of the apathy. Of the predictors, only frontal cortical thinning correlated with the total NPI score.

CONCLUSIONS

The results of this study suggested that accumbens atrophy and frontotemporal cortical thinning, especially frontal cortical thinning, independently contributed to neuropsychiatric symptoms in patients with PD, while DAT uptake did not affect the neuropsychiatric symptoms.

Health-Related Quality of Life Is Severely Affected in Primary Orthostatic Tremor

Background

Primary orthostatic tremor (POT) is a movement disorder characterized by unsteadiness upon standing still due to a tremor affecting the legs. It is a gradually progressive condition with limited treatment options. Impairments in health-related quality of life (HQoL) seem to far exceed the physical disability associated with the condition.

Methods

A multi-center, mixed-methodology study was undertaken to investigate 40 consecutive patients presenting with POT to four movement disorder centers in France. HQoL was investigated using eight quantitative scales and a qualitative study which employed semi-structured interviews. Qualitative data were analyzed with a combination of grounded-theory approach.

Results

Our results confirm that HQoL in POT is severely affected. Fear of falling was identified as the main predictor of HQoL. The qualitative arm of our study explored our initial results in greater depth and uncovered themes not identified by the quantitative approach.

Conclusion

Our results illustrate the huge potential of mixed methodology in identifying issues influencing HQoL in POT. Our work paves the way for enhanced patient care and improved HQoL in POT and is paradigmatic of this modern approach for investigating HQoL issues in chronic neurological disorders.

Interrelations between cognitive dysfunction and motor symptoms of Parkinson's disease: behavioral and neural studies

Parkinson's disease (PD) is characterized by a range of motor symptoms. Besides the cardinal symptoms (tremor, bradykinesia/akinesia, and rigidity), PD patients also show other motor deficits, including gait disturbance, speech deficits, and impaired handwriting. However, along with these key motor symptoms, PD patients also experience cognitive deficits in attention, executive function, working memory, and learning. Recent evidence suggests that these motor and cognitive deficits of PD are not completely dissociable, as aspects of cognitive dysfunction can impact motor performance in PD. In this article, we provide a review of behavioral and neural studies on the associations between motor symptoms and cognitive deficits in PD, specifically akinesia/bradykinesia, tremor, gait, handwriting, precision grip, and speech production. This review paves the way for providing a framework for understanding how treatment of cognitive dysfunction, for example cognitive rehabilitation programs, may in turn influence the motor symptoms of PD.

Pimavanserin: Potential Treatment For Dementia-Related Psychosis

Psychosis is common across dementia types with a prevalence of 20% to 70%. Currently, no pharmacologic treatment is approved for dementia-related psychosis. Atypical antipsychotics are frequently used to treat these disorders, despite significant safety concerns. Pimavanserin, a selective 5-HT2A inverse agonist/antagonist, was approved in the U.S. for treating hallucinations and delusions associated with Parkinson's disease psychosis (PDP). Patients in the pimavanserin group experienced a significant (p=0.001) improvement in Scale for the Assessment of Positive Symptoms - Parkinson's disease (SAPS-PD) scores vs. placebo. In a subgroup analysis of patients with cognitive impairment (MMSE score ≥21 but ≤24), the observed improvement on the SAPS-PD with pimavanserin (N=50) was also significant (p=0.002) and larger than in the overall study population without an adverse effect on cognition. In a Phase 2 study with pimavanserin in Alzheimer's disease psychosis, pimavanserin significantly (p=0.045) improved psychosis at Week 6 vs. placebo on the NPI-NH Psychosis Score (PS). In a prespecified subgroup of patients with a baseline NPI-NH PS ≥12, a substantively larger treatment effect (p=0.011) was observed vs. participants with NPI-NH PS <12. The results of these studies in cognitively impaired patients with PDP provided the scientific foundation for an ongoing study of pimavanserin for treating patients with dementia-related psychosis associated with the most common neurodegenerative disorders. The study uses a relapse-prevention design with the endpoint of time-to-relapse of psychosis to evaluate the long-term efficacy and safety of pimavanserin as a potential treatment for hallucinations and delusions of dementia-related psychosis.

Hospital care for mental health and substance abuse conditions in Parkinson's disease

OBJECTIVE

The objective of this study was to examine mental health conditions among hospitalized individuals with Parkinson's disease in the United States.

METHODS

This was a serial cross-sectional study of hospitalizations of individuals aged ≥60 identified in the Nationwide Inpatient Sample dataset from 2000 to 2010. We identified all hospitalizations with a diagnosis of PD, alcohol abuse, anxiety, bipolar disorder, depression, impulse control disorders, mania, psychosis, substance abuse, and attempted suicide/suicidal ideation. National estimates of each mental health condition were compared between hospitalized individuals with and without PD. Hierarchical logistic regression models determined which inpatient mental health diagnoses were associated with PD, adjusting for demographic, payer, geographic, and hospital characteristics.

RESULTS

We identified 3,918,703 mental health and substance abuse hospitalizations. Of these, 2.8% (n = 104, 437) involved a person also diagnosed with PD. The majority of mental health and substance abuse patients were white (86.9% of PD vs 83.3% of non-PD). Women were more common than men in both groups (male:female prevalence ratio, PD: 0.78, 0.78-0.79, non-PD: 0.58, 0.57-0.58). Depression (adjusted odds ratio 1.32, 1.31-1.34), psychosis (adjusted odds ratio 1.25, 1.15-1.33), bipolar disorder (adjusted odds ratio 2.74, 2.69-2.79), impulse control disorders (adjusted odds ratio 1.51, 1.31-1.75), and mania (adjusted odds ratio 1.43, 1.18-1.74) were more likely among PD patients, alcohol abuse was less likely (adjusted odds ratio 0.26, 0.25-0.27). We found no PD-associated difference in suicide-related care.

CONCLUSIONS

PD patients have unique patterns of acute care for mental health and substance abuse. Research is needed to guide PD treatment in individuals with pre-existing psychiatric illnesses, determine cross provider reliability of psychiatric diagnoses in PD patients, and inform efforts to improve psychiatric outcomes. © 2016 International Parkinson and Movement Disorder Society.

Lysosomal defects in ATP13A2 and GBA associated familial Parkinson's disease

Genes encoding lysosomal proteins, such as ATP13A2 and GBA, are associated with familial Parkinson's disease (PD). Heterozygous mutations in GBA are strongly associated with familial PD. ATP13A2, which encodes a lysosomal P-type ATPase, has been identified as the causative gene for Kufor-Rakeb syndrome. While lysosomal dysfunction due to these mutations exhibited early onset Parkinsonism, each animal model demonstrated different pathological mechanisms. Clinicogenetic and animal model studies recently identified several lysosomal alterations that play a role in the pathogenesis of PD.

Past, present, and future of Parkinson's disease: A special essay on the 200th Anniversary of the Shaking Palsy

This article reviews and summarizes 200 years of Parkinson's disease. It comprises a relevant history of Dr. James Parkinson's himself and what he described accurately and what he missed from today's perspective. Parkinson's disease today is understood as a multietiological condition with uncertain etiopathogenesis. Many advances have occurred regarding pathophysiology and symptomatic treatments, but critically important issues are still pending resolution. Among the latter, the need to modify disease progression is undoubtedly a priority. In sum, this multiple-author article, prepared to commemorate the bicentenary of the shaking palsy, provides a historical state-of-the-art account of what has been achieved, the current situation, and how to progress toward resolving Parkinson's disease. © 2017 International Parkinson and Movement Disorder Society.

Caregiver Burden in Parkinson Disease: A Critical Review of Recent Literature

Burden is a negative psychological state induced in caregivers by the demands of providing care to a person with an illness or a disability. Managing caregiver burden in Parkinson disease (PD) is significant because informal caregivers make a substantial contribution to the well-being of persons with PD, incurring financial, social, and personal losses. Failure to recognize and manage caregiver burden may lead to burnout and premature institutionalization of the person with PD. We conducted a comprehensive literature review to identify and summarize factors that may amplify burden, including motor and nonmotor symptoms of PD, caregiver psychiatric symptoms, and caregiver coping style. We review instruments designed to sample the construct of burden among caregivers and evaluate interventions that may reduce burden, either by directly targeting caregivers or by treating PD symptoms associated with burden. We aim to provide a concise synopsis of these issues for the clinician or researcher working with this population in order to facilitate recognition of caregiver burden, provide accurate assessment, administer appropriate interventions, and stimulate further research in this area.

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.

Discordance Between Physician Assessment and Patient-Reported Depressive Symptoms in Parkinson Disease

OBJECTIVE

To assess concordance between physician assessment and patient-reported symptoms when screening for depression in Parkinson disease (dPD).

BACKGROUND

Depression in Parkinson disease is highly prevalent (∼40%) and has a significant impact on quality of life and disability, yet physician recognition and treatment remain inadequate.

METHODS

One thousand seventy-six patients with PD completed the Brief Symptom Inventory-18 (BSI-18), a screening questionnaire for psychiatric symptoms, which was compared to item #3 (depression) on the Unified Parkinson's Disease Rating Scale (UPDRS).

RESULTS

The mean BSI-18 depression score was 51.4 (9.7). Of the 170 (16%) patients screening positive for dPD on the BSI-18, 104 (61%) were not recognized as depressed by neurologists on the UPDRS. Factors associated with lower neurologist recognition included male gender, better mental health quality of life, and lack of antidepressant use.

CONCLUSION

More than 60% of patients screening positive for depression on self-report were not recognized by neurologists on the UPDRS. A patient-reported screening tool for depression may improve recognition and management of dPD.

Antipsychotic Use and Physical Morbidity in Parkinson Disease

OBJECTIVE

To determine if antipsychotic (AP) use in Parkinson disease (PD) patients is associated with increased physical morbidity.

METHODS

Veterans Health Administration data (1999-2010) was used to examine physical morbidity risk associated with AP use in idiopathic PD patients with stable recent physical health. We compared 180-day morbidity rates in patients initiating an AP with matched non-AP users who survived for 180 days (matched on age, sex, race, index year, presence and duration of dementia, PD duration, delirium, hospitalization, Charlson Comorbidity Index, and new non-psychiatric medications; covarying for psychosis). Outcomes were 180-day emergency department (ED), and inpatient and outpatient visits.

RESULTS

There were 6,679 matched PD pairs. Any AP use was associated with an increased risk of ED visit (HR: 1.64, 95% CI: 1.51, 1.77), inpatient care (HR: 1.58, 95% CI: 1.46, 1.71), and outpatient visits (IRR: 1.08, 95% CI: 1.05, 1.12). The risk was significantly higher for atypical AP use compared with nonuse for all three morbidity outcomes, and was similar for atypical and typical AP use.

CONCLUSIONS

Any AP use, and atypical AP use, are associated with significantly increased physical morbidity risk in PD patients, as evidenced by increased ED, inpatient, and outpatient visits. These findings, which require replication, extend the risk associated with use of APs in this population from mortality to a broader range of adverse outcomes, and further highlight the need to use APs cautiously in PD patients.

Multiple modality biomarker prediction of cognitive impairment in prospectively followed de novo Parkinson disease

OBJECTIVES

To assess the neurobiological substrate of initial cognitive decline in Parkinson's disease (PD) to inform patient management, clinical trial design, and development of treatments.

METHODS

We longitudinally assessed, up to 3 years, 423 newly diagnosed patients with idiopathic PD, untreated at baseline, from 33 international movement disorder centers. Study outcomes were four determinations of cognitive impairment or decline, and biomarker predictors were baseline dopamine transporter (DAT) single photon emission computed tomography (SPECT) scan, structural magnetic resonance imaging (MRI; volume and thickness), diffusion tensor imaging (mean diffusivity and fractional anisotropy), cerebrospinal fluid (CSF; amyloid beta [Aβ], tau and alpha synuclein), and 11 single nucleotide polymorphisms (SNPs) previously associated with PD cognition. Additionally, longitudinal structural MRI and DAT scan data were included. Univariate analyses were run initially, with false discovery rate = 0.2, to select biomarker variables for inclusion in multivariable longitudinal mixed-effect models.

RESULTS

By year 3, cognitive impairment was diagnosed in 15-38% participants depending on the criteria applied. Biomarkers, some longitudinal, predicting cognitive impairment in multivariable models were: (1) dopamine deficiency (decreased caudate and putamen DAT availability); (2) diffuse, cortical decreased brain volume or thickness (frontal, temporal, parietal, and occipital lobe regions); (3) co-morbid Alzheimer's disease Aβ amyloid pathology (lower CSF Aβ 1-42); and (4) genes (COMT val/val and BDNF val/val genotypes).

CONCLUSIONS

Cognitive impairment in PD increases in frequency 50-200% in the first several years of disease, and is independently predicted by biomarker changes related to nigrostriatal or cortical dopaminergic deficits, global atrophy due to possible widespread effects of neurodegenerative disease, co-morbid Alzheimer's disease plaque pathology, and genetic factors.

Unilateral ultra-brief pulse electroconvulsive therapy for depression in Parkinson's disease

OBJECTIVES

Electroconvulsive therapy (ECT) has demonstrated efficacy in treating core symptoms of Parkinson's disease (PD); however, widespread use of ECT in PD has been limited due to concern over cognitive burden. We investigated the use of a newer ECT technology known to have fewer cognitive side effects (right unilateral [RUL] ultra-brief pulse [UBP]) for the treatment of medically refractory psychiatric dysfunction in PD.

MATERIALS AND METHODS

This open-label pilot study included 6 patients who were assessed in the motoric, cognitive, and neuropsychiatric domains prior to and after RUL UBP ECT. Primary endpoints were changes in total score on the HAM-D-17 and GDS-30 rating scales.

RESULTS

Patients were found to improve in motoric and psychiatric domains following RUL UBP ECT without cognitive side effects, both immediately following ECT and at 1-month follow-up.

CONCLUSIONS

This study demonstrates that RUL UBP ECT is safe, feasible, and potentially efficacious in treating multiple domains of PD, including motor and mood, without clear cognitive side effects.

Parkinson disease

Parkinson disease is the second-most common neurodegenerative disorder that affects 2-3% of the population ≥65 years of age. Neuronal loss in the substantia nigra, which causes striatal dopamine deficiency, and intracellular inclusions containing aggregates of α-synuclein are the neuropathological hallmarks of Parkinson disease. Multiple other cell types throughout the central and peripheral autonomic nervous system are also involved, probably from early disease onwards. Although clinical diagnosis relies on the presence of bradykinesia and other cardinal motor features, Parkinson disease is associated with many non-motor symptoms that add to overall disability. The underlying molecular pathogenesis involves multiple pathways and mechanisms: α-synuclein proteostasis, mitochondrial function, oxidative stress, calcium homeostasis, axonal transport and neuroinflammation. Recent research into diagnostic biomarkers has taken advantage of neuroimaging in which several modalities, including PET, single-photon emission CT (SPECT) and novel MRI techniques, have been shown to aid early and differential diagnosis. Treatment of Parkinson disease is anchored on pharmacological substitution of striatal dopamine, in addition to non-dopaminergic approaches to address both motor and non-motor symptoms and deep brain stimulation for those developing intractable L-DOPA-related motor complications. Experimental therapies have tried to restore striatal dopamine by gene-based and cell-based approaches, and most recently, aggregation and cellular transport of α-synuclein have become therapeutic targets. One of the greatest current challenges is to identify markers for prodromal disease stages, which would allow novel disease-modifying therapies to be started earlier.

Impact of Combined Subthalamic Nucleus and Substantia Nigra Stimulation on Neuropsychiatric Symptoms in Parkinson's Disease Patients

The goal of the study was to compare the tolerability and the effects of conventional subthalamic nucleus (STN) and combined subthalamic nucleus and substantia nigra (STN+SNr) high-frequency stimulation in regard to neuropsychiatric symptoms in Parkinson's disease patients. In this single center, randomized, double-blind, cross-over clinical trial, twelve patients with advanced Parkinson's disease (1 female; age: 61.3 ± 7.3 years; disease duration: 12.3 ± 5.4 years; Hoehn and Yahr stage: 2.2 ± 0.39) were included. Apathy, fatigue, depression, and impulse control disorder were assessed using a comprehensive set of standardized rating scales and questionnaires such as the Lille Apathy Rating Scale (LARS), Modified Fatigue Impact Scale (MFIS), Becks Depression Inventory (BDI-I), Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease Rating Scale (QUIP-RS), and Parkinson's Disease Questionnaire (PDQ-39). Three patients that were initially assigned to the STN+SNr stimulation mode withdrew from the study within the first week due to discomfort. Statistical comparison of data retrieved from patients who completed the study revealed no significant differences between both stimulation conditions in terms of mean scores of scales measuring apathy, fatigue, depression, impulse control disorder, and quality of life. Individual cases showed an improvement of apathy under combined STN+SNr stimulation. In general, combined STN+SNr stimulation seems to be safe in terms of neuropsychiatric side effects, although careful patient selection and monitoring in the short-term period after changing stimulation settings are recommended.

'There was no great ceremony': patient narratives and the diagnostic encounter in the context of Parkinson's

This paper draws on stories of diagnosis that emerged from a broader narrative study exploring the lived experience of Parkinson's (n.37). Despite the life-changing nature of their diagnosis, participants' narratives highlighted considerable shortcomings in the way in which their diagnostic encounter was handled, echoing the findings of previous research in which it has been noted that 'the human significance' of diagnosis was passed over. Building on the literature, this paper provides empirical material that reveals the sensitivities involved at the moment of diagnosis. By examining both the structure and content of participants' narratives, this article discusses the diagnostic encounter in relation to three key concepts that connected many participants' stories: a 'bareness' or lack of 'ceremony', a sense of emotional and physical 'abandonment' and the impact on a person's illness story when faced with a 'hierarchy' of illness. This paper aims to raise awareness of contemporary issues related to the diagnosis of Parkinson's, and invites reflection on how diagnosis might be undertaken in a way that truly acknowledges its human significance.