Neuropsychiatric Symptoms in Parkinson's Disease

Efficacy and safety of acupuncture therapy for neuropsychiatric symptoms among patients with Parkinson's disease: A systematic review and meta-analysis

OBJECTIVE

To systematically evaluate the efficacy and safety of acupuncture therapy for neuropsychiatric symptoms in patients with Parkinson's disease.

METHODS

We searched eight databases from their inception until 14 April 2024, including PubMed, Cochrane Library, Embase, Web of Science, SinoMed, China National Knowledge Infrastructure, China Science and Technology Periodical Database, and Wanfang Database. The search aimed to find randomized controlled trials assessing the effectiveness of acupuncture for neuropsychiatric symptoms in patients with Parkinson's disease. Literature screening and data extraction were performed independently by the authors. Meta-analysis was conducted using RevMan V.5.3 software, and Stata 17.0 software was used for detecting publication bias and performing sensitivity analysis.

RESULTS

Twenty-eight studies, involving 2148 participants, met the inclusion criteria. The meta-analysis revealed that acupuncture therapy improved depression-related scale scores (standardized mean difference (SMD) = -0.70, 95%CI [-0.98, -0.42], p < 0.00001), anxiety-related scale scores (SMD = -0.78, 95% CI [-1.43, -0.14], p = 0.02), Montreal Cognitive Assessment scores (weighted mean difference (WMD) = 2.74, 95% CI [2.43, 3.05], p < 0.00001), Mini Mental State Examination scores (WMD = 2.36, 95% CI [0.78, 3.94], p = 0.003), Yale-Brown Obsessive Compulsive Scale scores, and Parkinson's Disease Questionnaire-39 scores (WMD = -2.66, 95% CI [-4.83, -0.49], p = 0.02) compared to controls.

CONCLUSION

This review supports the application of acupuncture to reduce the severity of neuropsychiatric symptoms including depression, anxiety, and impulse control disorders, and to improve cognition and quality of life in patients with Parkinson's disease. The adverse effects associated with acupuncture, either alone or as adjunctive therapy, were relatively minor.

Efficacy and safety of acupuncture therapy for Parkinson's disease with neuropsychiatric symptoms: protocol for a systematic review and meta-analysis

INTRODUCTION

Neuropsychiatric symptoms (NPS) are common non-motor symptoms among patients with Parkinson's disease (PD) and significantly impact their overall quality of life detrimentally. Several studies have reported the clinical effect of acupuncture therapy in treating NPS in PD. Therefore, the objective of this systematic review is to evaluate the potential inclusion of acupuncture therapy as an integral component of complementary treatment for PD with NPS.

METHODS AND ANALYSIS

From their inception until 1 December 2023, we will search eight databases, including PubMed, Cochrane Library, Embase, Web of Science, China National Knowledge Infrastructure, China Science Periodical Database, Chinese Citation Database and China Biology Medicine disc for randomised controlled trials examining the effectiveness of acupuncture for PD with NPS. Literature screening and data extraction will be carried out independently by the authors. RevMan V.5.3 software will be used for meta-analysis, while the Cochrane risk-of-bias tool will assess the potential for bias.

ETHICS AND DISSEMINATION

This systematic review protocol does not require ethical approval because it does not include private information or data of participants. This article will be published in a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42022324494.

The effects of medical comorbidity, cognition, and age on patient-reported outcomes in Parkinson's disease

OBJECTIVE

The purpose of this cross-sectional study was to compare the independent contributions of medical comorbidity, cognition, and age on patient-reported outcomes in Parkinson's disease (PD).

METHODS

572 PD patients completed the Patient-Reported Outcome Measurement Information System (PROMIS®)-29 v2.0 Profile (physical function, anxiety, depression, fatigue, sleep disturbance, satisfaction with participation in social roles, pain interference) and PROMIS Global Health (mental health and physical health) scales. Comorbidity was measured with the Cumulative Illness Rating Scale-Geriatric (CIRS-G) and cognition with the Montreal Cognitive Assessment (MoCA). Multiple regression models examined the 9 PROMIS measures as predicted by comorbidity, cognition, and age, adjusting for demographic and clinical characteristics (UPDRS and disease duration).

RESULTS

Comorbidity was associated with poorer outcomes in all nine PROMIS domains. Cognition was associated with two of nine domains: physical function and anxiety. Age was associated with five domains: anxiety, depression, sleep disturbance, satisfaction with participation in social roles, and global mental health. Comorbidity showed greater effects on all nine domains than cognition or age (higher standardized beta coefficients).

CONCLUSION

Medical comorbidity, cognition, and age have different impacts on patient-reported outcomes in PD. Medical comorbidity has a greater impact than either cognition or age on a range of patient-reported physical and mental health domains. Medical comorbidity is an important contributor to the patient's perspective of their physical and mental health.

Neuropsychiatric symptoms in spinocerebellar ataxias and Friedreich ataxia

Apart from its role in motor coordination, the importance of the cerebellum in cognitive and affective processes has been recognized in the past few decades. Spinocerebellar ataxias (SCA) and Friedreich ataxia (FRDA) are rare neurodegenerative diseases of the cerebellum presenting mainly with a progressive loss of gait and limb coordination, dysarthria, and other motor disturbances, but also a range of cognitive and neuropsychiatric symptoms. This narrative review summarizes the current knowledge on neuropsychiatric impairment in SCA and FRDA. We discuss the prevalence, clinical features and treatment approaches in the most commonly reported domains of depression, anxiety, apathy, agitation and impulse dyscontrol, and psychosis. Since these symptoms have a considerable impact on patients' quality of life, we argue that further research is mandated to improve the detection and treatment options of neuropsychiatric co-morbidities in ataxia patients.

Grey matter volume loss in Parkinson's disease psychosis and its relationship with serotonergic gene expression: A meta-analysis

BACKGROUND

Neuroanatomical alterations underlying psychosis in Parkinson's Disease (PDP) remain unclear. We carried out a meta-analysis of MRI studies investigating the neural correlates of PDP and examined its relation with dopaminergic and serotonergic receptor gene expression.

METHODS

PubMed, Web of Science and Embase were searched for MRI studies (k studies = 10) of PDP compared to PD patients without psychosis (PDnP). Seed-based d Mapping with Permutation of Subject Images and multiple linear regression analyses was used to examine the relationship between pooled estimates of grey matter volume (GMV) loss in PDP and D1/D2 and 5-HT1a/5-HT2a receptor gene expression estimates from Allen Human Brain Atlas.

RESULTS

We observed lower grey matter volume in parietal-temporo-occipital regions (PDP n = 211, PDnP, n = 298). GMV loss in PDP was associated with local expression of 5-HT1a (b = 0.109, p = 0.012) and 5-HT2a receptors (b= -0.106, p = 0.002) but not dopaminergic receptors.

CONCLUSION

Widespread GMV loss in the parieto-temporo-occipital regions may underlie PDP. Association between grey matter volume and local expression of serotonergic receptor genes may suggest a role for serotonergic receptors in PDP.

Evaluation of betulinic acid effects on pain, memory, anxiety, catalepsy, and oxidative stress in animal model of Parkinson's disease

Parkinson's disease (PD) is known for motor impairments. Betulinic acid (BA) is a natural compound with antioxidant activity. The present study addresses the question of whether BA affects motor and non-motor dysfunctions and molecular changes in the rat model of PD. The right medial forebrain bundle was lesioned by injection of 6-hydroxydopamine in Male Wistar rats (10-12 weeks old, 270-320 g). Animals were divided into Sham, PD, 3 treated groups with BA (0.5, 5, and 10 mg/kg, IP), and a positive control group received L-dopa (20 mg/kg, P.O) for 7 days. rigidity, anxiety, analgesia, and memory were assessed by bar test, open-field, elevated plus-maze (EPM), tail-flick, and shuttle box. Additionally, the malondialdehyde (MDA), Superoxide dismutase (SOD), glutathione peroxidase (GPx) activity, Brain-derived neurotrophic factor (BDNF) and Interleukin 10 (IL10) levels in the whole brain were measured. BA significantly reversed the 6-hydroxydopamine-induced motor and memory complication in the bar test and shuttle box. It modified anxiety-like behavior neither in open-field nor in EPM. It only decreased the time spent in open arms. Moreover, no significant changes were found in the tail-flick between treatment and sham groups. On the other hand, the level of MDA & IL10 were decreased, while the activity of GPx levels of SOD & BDNF in the rats' brains was increased. Our results showed that BA as a free radical scavenger can account for a possible promise as a good therapeutic agent for motor and non-motor complications in PD however further studies may be needed.

Stigma, self-compassion, and psychological distress among people with Parkinson's

PURPOSE

People with Parkinson's disease (hereafter Parkinson's) can experience stigma through the attitudes and actions of others (enacted stigma) and through anticipation of enacted stigma and internalisation of negative stereotypes (felt stigma). Self-compassion may protect against the impact of stigma. This study aimed to investigate the relationships between self-compassion, stigma, and psychological distress among people with Parkinson's.

METHODS

A total of 130 people with Parkinson's completed questionnaires measuring self-compassion, enacted and felt stigma, and depression, anxiety, and stress. Correlation, mediation, and moderation models were used to investigate relationships between variables.

RESULTS

All variables correlated significantly in the expected directions. Felt stigma mediated the relationship between self-compassion and the three outcome variables - depression, anxiety, and stress. Self-compassion did not moderate the relationship between enacted stigma and distress and suggested enacted stigma was associated with distress, regardless of levels of self-compassion.

CONCLUSIONS

Self-compassion and both enacted and felt stigma are important predictors of distress for people with Parkinson's. Part of the relationship between lower self-compassion and psychological distress appears to occur via the internalisation of stigma. These findings may be relevant to the development of individualised and societal interventions with the aim of improving the psychological wellbeing of people with Parkinson's.Implications for rehabilitationSelf-compassion was associated with lower levels of psychological distress (i.e., depression, anxiety, and stress) and self-stigma partially mediated this relationship.Self-compassion did not moderate the relationship between enacted stigma and psychological distress, suggesting enacted stigma increases distress, regardless of self-compassion.The development and assessment of the effectiveness of compassion-focused interventions tailored for people with Parkinson's may be important as well as systemic stigma focused interventions.

Neuropsychiatric Symptom Burden across Neurodegenerative Disorders and its Association with Function

OBJECTIVE

Neuropsychiatric symptoms (NPS) are prevalent in neurodegenerative disorders, however, their frequency and impact on function across different disorders is not well understood. We compared the frequency and severity of NPS across Alzheimer's disease (AD) (either with mild cognitive impairment or dementia), Cerebrovascular disease (CVD), Parkinson's disease (PD), frontotemporal dementia (FTD), and amyotrophic lateral sclerosis (ALS), and explored the association between NPS burden and function.

METHODS

We obtained data from Ontario Neurodegenerative Disease Research Initiative (ONDRI) that included following cohorts: AD (N = 111), CVD (N = 148), PD (N = 136), FTD (N = 50) and ALS (N = 36). We compared the frequency and severity of individual NPS (assessed by the neuropsychiatric inventory questionnaire) across cohorts using generalized estimating equations and analysis of variance. Second, we assessed the relationship of NPS burden with instrumental (iADLs) and basic (ADLs) activities of living across cohorts using multivariate linear regression while adjusting for relevant demographic and clinical covariates.

RESULTS

Frequency of NPS varied across cohorts (χ²₍₄₎ = 34.4, p < .001), with post-hoc tests showing that FTD had the greatest frequency as compared to all other cohorts. The FTD cohort also had the greatest severity of NPS (H₍₄₎ = 34.5, p < .001). Further, there were differences among cohorts in terms of the association between NPS burden and ADLs (F_(4,461) = 3.1, p = 0.02). Post-hoc comparisons suggested that this finding was driven by the FTD group, however, the differences did not remain significant following Bonferroni correction. There were no differences among cohorts in terms of the association between NPS burden and IADLs.

CONCLUSIONS

NPS frequency and severity are markedly greater in FTD as compared to other neurodegenerative diseases. Further, NPS burden appears to be associated differently with function across neurodegenerative disorders, highlighting the need for individualized clinical interventions.

Potential roles of oxidative distress on neurodegeneration in Parkinson's disease with neuropsychiatric symptoms

Background

Neuropsychiatric symptoms (NPSs) belong to a category of non-motor symptoms of Parkinson's disease (PD), which seriously compromise the quality of life and prognosis of PD. This study focused on the correlations between NPSs, free radicals, neuroinflammatory factors, and neuropathological proteins in cerebrospinal fluid (CSF) in patients with PD, aiming to provide insights into the potential mechanisms and therapeutic target for PD with NPSs (PD-NPSs).

Methods

In total, 129 patients with PD were enrolled and assessed by the Neuropsychiatric Symptoms Inventory (NPI); they were divided into the PD-NPSs group (75 patients) and PD with no NPSs (PD-nNPSs) group (54 patients). The levels of hydrogen peroxide (H₂O₂) and nitric oxide (NO), and hydroxyl radical (·OH), anti-oxidative enzyme, neuroinflammatory factors, and neuropathological proteins in CSF from patients with PD were measured. The levels of the above variables were compared between PD-NPSs and PD-nNPSs groups, and correlation analyses among the above variables were conducted.

Results

(1) The levels of H₂O₂ and NO in CSF from the PD-NPSs group were significantly elevated compared with the PD-nNPSs group (p = 0.001), and NPI score positively correlated with the levels of H₂O₂ and NO (r = 0.283, P = 0.001; r = 0.231, P = 0.008). Reversely, total superoxide dismutase (tSOD) activity in CSF from the PD-NPSs group was significantly reduced compared with the PD-nNPSs group (p = 0.011), and negatively correlated with NPI score (r = -0.185, p = 0.036). (2) The tumor necrosis factor (TNF)-α level in CSF from the PD-NPSs group was significantly decreased compared with the PD-nNPSs group (p = 0.002) and negatively correlated with NPI score (r = -0.211, p = 0.016). (3) The total tau (T-tau) level in CSF from the PD-NPSs group was significantly higher than in the PD-nNPSs group (p = 0.014) and positively correlated with the NPI score (r = 0.167, p = 0.060). (4) The levels of H₂O₂ and NO positively correlated with the T-tau level in CSF from the PD-NPSs group (r = 0.183, p = 0.039; r = 0.251, P = 0.004), and the levels of TNF-α and T-tau showed a negative correlation (r = -0.163, p = 0.067).

Conclusion

Oxidative distress characterized by the elevations of H₂O₂ and NO levels may closely correlate with the neurodegeneration in brain regions related to PD-NPSs. Thus, therapeutic antioxidants may become an important target for PD-NPSs therapy.

Use of common spatial patterns for early detection of Parkinson's disease

One of the most common diseases that affects human brain is Parkinson's disease. Detection of Parkinson's disease (PD) poses a serious challenge. Robust methods for feature extraction allowing separation between the electroencephalograms (EEG) of healthy subjects and PD patients are required. We used the EEG records of healthy subjects and PD patients which were subject to auditory tasks. We used the common spatial patterns (CSP) and Laplacian mask as methods to allow robust selection and extraction of features. We used the derived CSP whitening matrix to determine those channels that are the most promising in the terms of differentiating between EEGs of healthy controls and of PD patients. Using the selection of features calculated using the CSP we managed to obtain the classification accuracy of 85% when classifying EEG records belonging to groups of controls or PD patients. Using the features calculated using the Laplacian operator we obtained the classification accuracy of 90%. Diagnosing the PD in early stages using EEG is possible. The CSP proved to be a promising technique to detect informative channels and to separate between the groups. Use of the combination of features calculated using the Laplacian offers good separability between the two groups.

Detailed insight into the pathophysiology and the behavioral complications associated with the Parkinson's disease and its medications

Background

The loss of dopamine neurons in the substantia nigra, as well as other mostly catecholaminergic neurons, causes many of the motor symptoms that define Parkinson's disease. Parkinson's disease is commonly thought of as a movement disorder, the significant prevalence of psychiatric complications such as cognitive impairment, and psychosis suggests it should be considered a neuropsychiatric illness, and all behavioral complications are linked to growing disability and the medication.

Main body

Apart from the disease-induced abnormalities, there are several other side effects of the disease and also from the medication used to prevent the disease. This article focuses on the pathogenesis of Parkinson’s disease and also the behavioral abnormalities caused by the disease and its medication. The study's data were gathered by searching several review articles and research papers from a variety of sources, including Elsevier, PubMed, Research Gate, Journal of Pharmaceutical Science, etc., from the year 1985 to 2021. Parkinson's disease is a neurodegenerative disease caused by a variety of complex processes. It is responsible not just for motor symptoms, but also for a variety of behavioral symptoms that can arise as a result of the disease and/or medication.

Conclusion

Only symptomatic drugs are available; thus, finding treatments that directly address the disease mechanisms causing Parkinson’s disease is essential. To alleviate the disease's burden on patients and their families, better treatments for the neuropsychiatric repercussions of Parkinson's disease are required.

Graphical Abstract

Age-Dependent Neuropsychiatric Symptoms in the NF-κB/c-Rel Knockout Mouse Model of Parkinson’s Disease

Non-motor symptoms are frequently observed in Parkinson’s disease (PD) and precede the onset of motor deficits by years. Among them, neuropsychiatric symptoms, including anxiety, depression, and apathy, are increasingly considered as a major challenge for patients with PD and their caregivers. We recently reported that mice lacking the nuclear factor-κB (NF-κB)/c-Rel protein (c-rel^–/– mice) develop an age-dependent PD-like pathology and phenotype characterized by the onset of non-motor symptoms, including constipation and hyposmia, starting at 2 months of age, and motor deficits at 18 months. To assess whether c-rel^–/– mice also suffer from neuropsychiatric symptoms, in this study we tested different cohorts of wild-type (wt) and c-rel^–/– mice at 3, 6, 12, and 18–20 months with different behavioral tests. Mice lacking c-Rel displayed anxiety and depressive-like behavior starting in the premotor phase at 12 months, as indicated by the analysis with the open field (OF) test and the forced swim test with water wheel (FST), respectively. A deficit in the goal-oriented nesting building test was detected at 18–20 months, suggesting apathetic behavior. Taken together, these results indicate that c-rel^–/– mice recapitulate the onset and the progression of PD-related neuropsychiatric symptoms. Therefore, this animal model may represent a valuable tool to study the prodromal stage of PD and for testing new therapeutic strategies to alleviate neuropsychiatric symptoms.

Functional Covariance Connectivity of Gray and White Matter in Olfactory-Related Brain Regions in Parkinson’s Disease

Before the onset of motor symptoms, Parkinson’s disease (PD) involves dysfunction of the anterior olfactory nucleus and olfactory bulb, causing olfactory disturbance, commonly resulting in hyposmia in the early stages of PD. Accumulating evidence has shown that blood oxygen level dependent (BOLD) signals in white matter are altered by olfactory disorders and related stimuli, and the signal changes in brain white matter pathways show a certain degree of specificity, which can reflect changes of early olfactory dysfunction in Parkinson’s disease. In this study, we apply the functional covariance connectivity (FCC) method to decode FCC of gray and white matter in olfactory-related brain regions in Parkinson’s disease. Our results show that the dorsolateral prefrontal, anterior entorhinal cortex and fronto-orbital cortices in the gray matter have abnormal connectivity with the posterior corona radiata and superior corona radiata in white matter in patients with Parkinson’s hyposmia. The functional covariance connection strength (FCS) of the right dorsolateral prefrontal cortex and white matter, and the covariance connection strength of the left superior corona radiata and gray matter function have potential diagnostic value. These results demonstrate that alterations in FCC of gray and white matter in olfactory-related brain regions can reflect the change of olfactory function in the early stages of Parkinson’s disease, indicating that it could be a potential neuroimaging marker for early diagnosis.

Eye-gaze Strategies During Facial Emotion Recognition in Neurodegenerative Diseases and Links With Neuropsychiatric Disorders

BACKGROUND

Facial emotion recognition (FER) is primarily and severely impaired in individuals with the behavioral variant of frontotemporal dementia (bvFTD) and is often mildy impaired in individuals with Alzheimer disease (AD) or Parkinson disease (PD). Such impairment is associated with inappropriate social behaviors.

OBJECTIVE

To determine whether FER impairment is linked to the use of inappropriate eye-gaze strategies to decode facial emotions, leading to misinterpretation of others' intentions and then to behavioral disorders.

METHOD

We assessed FER in 9 individuals with bvFTD, 23 with AD, and 20 with PD, as well as 22 healthy controls (HC), using the Reading the Mind in the Eyes (RME) Test and the Ekman Faces Test. Eye movements (number and duration of fixations) were recorded with an eye-tracking device. Behavior was assessed using the Neuropsychiatric Inventory.

RESULTS

FER was mildly impaired in the AD and PD groups and severely impaired in the bvFTD group. FER impairment was accompanied by an increase in the number of fixations and a more attracted gaze toward the lower part of one's face. FER impairment and an increase in the number of fixations were positively correlated with behavioral disorders.

CONCLUSION

Our study demonstrated a link between FER impairment, modification of eye-gaze strategies during the observation of emotional faces, and behavioral disorders in individuals with bvFTD and those with AD or PD. These results suggest that an eye-gaze strategy rehabilitation program could have beneficial effects on emotion recognition and behavioral disorders in individuals with these diseases.

Sleep and circadian rhythms in Parkinson's disease and preclinical models

The use of animals as models of human physiology is, and has been for many years, an indispensable tool for understanding the mechanisms of human disease. In Parkinson's disease, various mouse models form the cornerstone of these investigations. Early models were developed to reflect the traditional histological features and motor symptoms of Parkinson's disease. However, it is important that models accurately encompass important facets of the disease to allow for comprehensive mechanistic understanding and translational significance. Circadian rhythm and sleep issues are tightly correlated to Parkinson's disease, and often arise prior to the presentation of typical motor deficits. It is essential that models used to understand Parkinson's disease reflect these dysfunctions in circadian rhythms and sleep, both to facilitate investigations into mechanistic interplay between sleep and disease, and to assist in the development of circadian rhythm-facing therapeutic treatments. This review describes the extent to which various genetically- and neurotoxically-induced murine models of Parkinson's reflect the sleep and circadian abnormalities of Parkinson's disease observed in the clinic.

Plasma Neurofilament Light and p-tau181 and Risk of Psychosis in Parkinson's Disease

BACKGROUND

Neuropsychiatric symptoms are common and important to people with Parkinson's disease (PD), but their etiology is poorly understood. Plasma neurofilament light (NfL) and p-tau181 are biomarkers of neuro-axonal degeneration and tau pathology respectively, which have yet to be explored in association with the affective and psychotic symptoms in PD.

OBJECTIVE

To investigate the relationship between plasma NfL and p-tau181 with the affective and psychotic symptoms in PD.

METHODS

We assessed the baseline concentration of plasma NfL and p-tau181 in a cohort of 108 patients with PD and 38 healthy controls. A subgroup of patients (n = 63) were assessed annually with clinical measures for up to 7 years. Psychotic symptoms were assessed using the Non-Motor Symptom Scale and affective symptoms were measured in the Hospital Anxiety and Depression Scale.

RESULTS

Baseline plasma NfL was a significant predictor of psychotic symptoms longitudinally across the study adjusted for age, Hoehn and Yahr stage, duration of follow up, duration of disease, baseline levodopa and dopamine agonist medication, and baseline cognition: (OR 8.15 [95% CI 1.40-47.4], p = 0.020). There was no association between NfL concentration and the cumulative prevalence of affective symptoms. Plasma p-tau181 concentration was not associated with psychotic or affective symptoms.

CONCLUSION

These findings suggest psychotic symptoms are associated with greater neurodegeneration in PD. Further studies are needed to explore NfL as a potential biomarker for psychosis in PD.

Caregiver Burden in Late-Stage Parkinsonism and Its Associations

BACKGROUND

Patients in the late stages of parkinsonism are highly dependent on others in their self-care and activities of daily living. However, few studies have assessed the physical, psychological and social consequences of caring for a person with late-stage parkinsonism.

PATIENTS AND METHODS

Five hundred and six patients and their caregivers from the Care of Late Stage Parkinsonism (CLaSP) study were included. Patients' motor and non-motor symptoms were assessed using the UPDRS and Non-motor symptom scale (NMSS), Neuropsychiatric inventory (NPI-12), and caregivers' health status using the EQ-5D-3 L. Caregiver burden was assessed by the Zarit Burden Interview (ZBI).

RESULTS

The majority of caregivers were the spouse or life partner (71.2%), and were living with the patient at home (67%). Approximately half of caregivers reported anxiety/depression and pain/discomfort (45% and 59% respectively). The factors most strongly associated with caregiver burden were patients' neuropsychiatric features on the total NPI score (r = 0.38, p < 0.0001), total NMSS score (r = 0.28, p < 0.0001), caring for male patients and patients living at home. Being the spouse, the hours per day assisting and supervising the patient as well as caregivers' EQ-5D mood and pain scores were also associated with higher ZBI scores (all p < 0.001).

CONCLUSION

The care of patients with late stage parkinsonism is associated with significant caregiver burden, particularly when patients manifest many neuropsychiatric and non-motor features and when caring for a male patient at home.

Parkinsonism and dementia

The aim of the present review is to summarize literature data on dementia in parkinsonian disorders. Cognitive decline and the gradual development of dementia are considered to be key features in the majority of parkinsonian conditions. The burden of dementia in everyday life of parkinsonian patients and their caregivers is vast and can be even more challenging to handle than the motor component of the disease. Common pathogenetic mechanisms involve the aggregation and spreading of abnormal proteins like alpha-synuclein, tau or amyloid in cortical and subcortical regions with subsequent dysregulation of multiple neurotransmitter systems. The degree of cognitive deterioration in these disorders is variable and ranges from mild cognitive impairment to severe cognitive dysfunction. There is also variation in the number and type of affected cognitive domains which can involve either a single domain like executive or visuospatial function or multiple ones. Novel genetic, biological fluid or imaging biomarkers appear promising in facilitating the diagnosis and staging of dementia in parkinsonian conditions. A significant part of current research in Parkinson's disease and other parkinsonian syndromes is targeted towards the cognitive aspects of these disorders. Stabilization or amelioration of cognitive outcomes represents a primary endpoint in many ongoing clinical trials for novel disease modifying treatments in this field. This article is part of the Special Issue "Parkinsonism across the spectrum of movement disorders and beyond" edited by Joseph Jankovic, Daniel D. Truong and Matteo Bologna.

Frequency of Non-motor Symptoms in Parkinson's Patients With Motor Fluctuations

Background: Non-motor symptoms (NMS), including neuropsychiatric, sleep, autonomic, and sensory domains, are an integral aspect of the clinical presentation of Parkinson disease (PD) and affect neurocognitive functioning as well as patients' and caregivers' well-being.

Objective: To describe the occurrence of NMS in PD patients with motor fluctuations in real-life condition.

Methods: The present study is a secondary analysis of a previous multinational, multicenter, retrospective-prospective cohort observational study (SYNAPSES). Patients with PD diagnosis and motor fluctuations aged ≥18 years were included. Data collected at the baseline visit were used for this study, and descriptive analyzes were conducted to describe the distribution of NMS in motor-fluctuating PD patients distributed according to different clinical characteristics.

Results: Of the 1,610 patients enrolled, 1,589 were included for the analysis (978 males and 611 females), with a mean age of 68.4 (SD = 9.6). Most patients had at least one NMS (88.5%). Sleep problems and psychiatric symptoms were the most prevalent NMS in motor fluctuating PD patients in all H and Y stages. Psychiatric disorders were more frequent in older patients and in patients with a larger number of years of PD diagnosis, while sleep problems were more preeminent in younger patients and with inferior disease duration.

Conclusions: The present findings further support the high prevalence of NMS in PD patients with motor fluctuations, thus reinforcing the need for assessing them for diagnostic accuracy and for delivering holistic care.

Candidate risk genes for bipolar disorder are highly conserved during evolution and highly interconnected

OBJECTIVES

Bipolar disorder (BPD) is a highly heritable psychiatric disorder whose genetic complexity and pathogenetic mechanisms are still being unraveled. The main goal of this work was to characterize BPD risk-gene candidates (identified by Nurnberger et al., JAMA Psychiatry 71:657, 2014, and Stahl et al., Nat. Genet. 51:793, 2019) with respect to their evolutionary conservation, associated phenotypes, and extent of gene-gene interactions.

METHODS

Database searches and BLAST were used to identify homologous counterparts of human BPD risk genes in C. elegans, zebrafish, and Drosophila. Phenotypes associated with the C. elegans genes were annotated and searched. With GeneMANIA, we characterized and quantified gene-gene interactions among members of the BPD gene set in comparison to randomly chosen gene sets of the same size.

RESULTS

BPD risk genes are highly conserved across species and are enriched for essential genes and genes associated with lethality and altered life span. They are significantly more interactive with each other in comparison to random genes. We identified syntenic blocks of risk genes, which provided potential insights into molecular pathways and co-morbidities associated with BPD including coronary disease, obesity, and decreased life expectancy.

CONCLUSIONS

BPD risk genes appear to be special in terms of their degree of conservation, interconnectedness, and pleiotropic effects that extend beyond a role in brain function. Key hub genes or pleiotropic regulatory components may represent attractive targets for future drug discovery.

Does an association between cigarette smoking and Parkinson's Disease-related psychosis exist? Insights from a large non-demented cohort

BACKGROUND

Parkinson's Disease-related Psychosis (PDP) encompasses a spectrum of symptoms ranging from "minor" hallucinations to formed hallucinations and delusions. Notably, cognitive impairment has been recognized as the strongest risk factor for PDP. Several evidences suggest a possible role of cigarette smoking in both cognition and psychotic syndromes.

OBJECTIVES

To evaluate the possible independent association between cigarette smoking and PDP in a large cohort of non-demented PD patients.

METHODS

A cohort of non-demented PD patients was selected from the FRAGAMP study population. All participants underwent a standardised structured questionnaire to assess demographic, clinical and environmental exposure data. Clinical features were assessed using UPDRS, HY stage, AIMS, MMSE and Hamilton Rating Scale for Depression. Presence of psychotic symptoms was assessed using UPDRS-I.2 score. Diagnosis of PDP was made according to NINDS/NIMH criteria.

RESULTS

Four hundred eighty-five non-demented PD patients were enrolled [292 men (60.2%); mean age ± SD 65.6 ± 9.8]. Among them, 28 (5.8%) had PDP. Multivariate analysis, adjusting by HY stage, MMSE and LED, shown an independent association between PDP and "nightmares-abnormal movements during sleep" and current smoking [adjOR 7.39 (95%CI 1.45-37.69; P-value 0.016)].

CONCLUSIONS

Our findings provide interesting insights about the possible role of current smoking in facilitating the occurrence of psychotic symptoms in PD.

Activation and blockade of dorsal hippocampal serotonin4 receptors produce antidepressant effects in the hemiparkinsonian rats

Depression is a common non-motor symptom in Parkinson's disease (PD). Although serotonin4 (5-HT4) receptors and the dorsal hippocampus (dHIP) are regarded to be involved in the depression, the mechanism underlying the effects of 5-HT4 receptors in the dHIP on PD-related depression should be further investigated. In the present study, unilateral 6-hydroxydopamine lesions of the medial forebrain bundle (MFB) increased the expressions of 5-HT4 receptors and its co-localization with glutamate neurons in the CA1, CA3 and dentate gyrus. Additionally, MFB lesions induced depressive-like behaviors in the sucrose preference and forced swimming tests. The activation or blockade of dHIP 5-HT4 receptors produced antidepressant effects in the MFB lesioned rats but not in control rats. Neurochemical results showed no changes of monoamines levels in the striatum, medial prefrontal cortex (mPFC), lateral habenula (LHb), and ventral hippocampus (vHIP) in control rats after intra-dHIP injection of 5-HT4 receptors agonist BIMU8 (26 μg/rat), antagonist GR 113808 (16 μg/rat) or GR 113808/BIMU8 (26 μg/16 μg/rat). But in the lesioned rats, BIMU8, GR113808 or GR 113808/BIMU8 injection increased dopamine levels in the striatum, mPFC, LHb, and vHIP and increased 5-HT levels in the LHb. Intra-dHIP injection of GR 113808 or GR 113808/BIMU8 also increased the noradrenaline levels in the mPFC and LHb. All these results suggest that activation or blockade dHIP 5-HT4 receptors produce antidepressant effects in the hemiparkinsonian rats, which may be related to the upregulation of 5-HT4 receptors in the dHIP and the changes of monoamines in the limbic and limbic-related brain regions.

Association Between Somatization and Nonmotor Symptoms Severity in People With Parkinson Disease

OBJECTIVE

To assess the frequency of somatization and its association with motor, nonmotor symptoms, and quality of life in persons with Parkinson disease (PD).

METHODS

A cross-sectional case-control study was carried out. Assessments included the List of 90 Symptoms somatic factor (SCL-90-R SOM), Movement Disorder Society Unified Parkinson's Ratings Scale (MDS-UPDRS), Non-Motor Symptom Scale (NMSS), Montreal Cognitive Assessment (MoCA), and Parkinson Questionnaire-8 (PDQ-8).

RESULTS

A total 93 persons with PD and 93 controls were included. Somatization within the PD group was 2 times more frequent compared to the control group (43% vs 21.5%, P = .003). Persons with PD had higher NMSS total scores (48.6 ± 42.6 vs 28.3 ± 30.4, P = .001). Patients with PD with somatization had worst MDS-UPDRS, NMSS, MoCA, and PDQ-8 (all P < .05).

CONCLUSION

Somatization is more frequent in persons with PD compared to healthy controls. Somatization in PD is associated with nonmotor symptoms and worst quality of life.

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.

A randomized controlled double-blind study of rotigotine on neuropsychiatric symptoms in de novo PD

Management of apathy, depression and anxiety in Parkinson’s disease (PD) represents a challenge. Dopamine agonists have been suggested to be effective. This multicenter, randomized (1:1), double-blind study assessed the 6-month effect of rotigotine versus placebo on apathy, depression and anxiety in de novo PD. The primary outcome was the change of apathy, measured with the LARS. The secondary outcomes were the change in depression and anxiety, measured with BDI-2 and STAI-trait and state. Forty-eight drug-naive PD patients were included. The primary outcome was not reached, with a surprisingly high placebo effect on apathy (60%). There was no significant difference in the change of depression at 6 months between rotigotine and placebo. Trait-anxiety was significantly improved by rotigotine compared to placebo (p = 0.04). Compared to placebo, low dose rotigotine significantly improved trait anxiety, but not apathy and depression. The major placebo effect on apathy points towards the importance of a multidisciplinary and tight follow-up in the management of neuropsychiatric symptoms.

Suicide in Parkinson's Disease: A Systematic Review

Psychiatric disorders and suicide have been reported in patients suffering from Parkinson's disease. The aims of the present paper were to determine whether patients with Parkinson's disease have an increased rate of suicide and to identify the clinical features possibly associated with suicide risk in Parkinson's disease. We also reviewed the studies on suicide risk in Parkinson's disease in patients after deep brain stimulation. We performed a Medline, Excerpta Medica, PsycLit, PsycInfo and Index Medicus search to identify all articles published on this topic from 1970 to 2019. The following search terms were used: suicide OR suicide attempt OR suicidal ideation OR suicide risk AND Parkinson's disease AND Parkinson's disease and deep brain stimulation. The studies we identified that assessed the suicide rate associated with Parkinson's disease yielded contrasting results, although an increase in suicidal ideation did emerge. The studies on the effect of deep brain stimulation on suicide risk in Parkinson's disease also reported mixed findings. Psychiatric symptoms, including depression, appear to be associated with suicide risk in patients with Parkinson's disease undergoing medical and after surgical treatment. The studies reviewed suggest that suicidal ideation is increased in Parkinson's disease. Further longitudinal studies designed to assess suicidality in this condition are still needed.

Evaluating rates of reporting symptoms of Parkinson's disease psychosis: provider versus targeted questionnaire

PURPOSE/AIM

A targeted questionnaire may help increase rates of reporting Parkinson's disease psychosis (PDP) symptoms. Despite the need for a rapid patient- and/or caregiver-administered screening tool for PDP symptoms, an appropriate tool is not yet available. This study developed a targeted PDP questionnaire and examined rates of reporting psychosis symptoms in response to the questionnaire compared to rates of reporting symptoms to healthcare providers during a routine visit.

MATERIALS AND METHODS

This was a single-center, cross-sectional observational study of patients at an outpatient neurology practice. Medical charts were screened for eligibility, and patients were contacted by telephone for informed consent.

RESULTS

A total of 25 patients (24%, N = 104) newly reported PDP symptoms in response to the targeted questionnaire. The frequency of reporting new symptoms in response to the questionnaire was statistically significantly greater compared to frequency of reporting symptoms without use of a targeted questionnaire (p < 0.0001).

CONCLUSIONS

A targeted questionnaire increases rates of reporting PDP symptoms, and based on frequency, severity, and distress ratings, may allow for capture of PDP symptoms earlier in the course of the disease. By using a questionnaire, patients reported symptom onset an average of 1.4 years earlier than patients who reported symptoms to their providers according to patient medical records.

Mild Behavioral Impairment in Parkinson's Disease: Data from the Parkinson's Disease Cognitive Impairment Study (PACOS)

Neuropsychiatric symptoms (NPS) have been frequently described in Parkinson's disease (PD), even in the earliest stages of the disease. Recently the construct of mild behavioral impairment (MBI) has been proposed as an at-risk state for incident cognitive decline and dementia. The aim of the present study is to evaluate the prevalence and associated factors of MBI in PD. Cross-sectional data from 429 consecutive PD patients enrolled in the PArkinson's disease COgnitive impairment Study (PACOS) were included in the study. All subjects underwent neuropsychological assessment, according to the MDS Level II criteria. NPS were evaluated with the Neuropsychiatric Inventory. Multivariate logistic regression models were used to evaluate clinical and behavioral characteristics, which are associated with PD-MBI. The latter was ascertained in 361 (84.1%) subjects of whom 155 (36.1%) were newly diagnosed patients (disease duration ≤1 year) and 206 (48.0%) had a disease duration >1 year. Furthermore, 68 (15.9%) out of 429 subjects were PDw (without MBI). Across the MBI domains, Impulse Dyscontrol was significantly more prevalent among PD-MBI with disease duration >1 year than newly diagnosed patients. The frequency of Social Inappropriateness and Abnormal Perception significantly increased throughout the entire PD-MBI sample with increasing Hoehn and Yahr (H&Y) stages. PD-MBI in newly diagnosed PD was significantly associated with H&Y stage (OR 2.35, 95% CI 1.05-5.24) and marginally with antidepressant drug use (OR 2.94, 95% CI 0.91-9.47), while in patients with a disease duration >1 year was associated with UPDRS-ME (OR 3.37, 95% CI 1.41-8.00). The overall MBI frequency in the PACOS sample was 84% and 36% among newly diagnosed patients. The presence of MBI mainly related to motor impairment and disability.

Neuropsychiatric symptoms in Parkinson's disease: association with caregiver distress and disease severity

OBJECTIVES

The condition of caregivers is important to the quality of care received by people with Parkinson's disease (PD), especially at the late disease stages. This study addresses the distress placed on caregivers by participants' neuropsychiatric symptoms at different stages of PD in Taiwan.

METHODS

This prospective study enrolled 108 people with PD. All participants were examined with the Unified Parkinson's Disease Rating Scale (UPDRS), Neuropsychiatric Inventory (NPI), Mini-Mental State Examination (MMSE), Cognitive Abilities Screening Instrument (CASI), and Clinical Dementia Rating (CDR) scale. Caregiver distress was measured using the Neuropsychiatric Inventory Caregiver Distress Scale (NPI-D). Statistical analysis was used to explore the PD-related factors that contribute to caregiver distress.

RESULTS

The mean follow-up interval in the 108 PD participants were 24.0 ± 10.2 months with no participant lost to follow-up due to death. NPI-distress (the sum of NPI caregiver distress scale across the 12 domains of the NPI) was positively correlated with NPI-sum (the total score across the 12 domains of the NPI) (r = 0.787, p < 0.001), CDR (r = 0.403, p < 0.001), UPRDS (r = 0.276, p = 0.004), and disease duration (r = 0.246, p = 0.002), but negatively correlated with CASI (r = -0.237, p = 0.043) and MMSE (r = -0.281, p < 0.001). Multiple linear regression analysis showed that only NPI-sum and disease duration were independently correlated with NPI-distress.

CONCLUSION

The disease duration and NPI-sum are independent predictors of caregiver distress in Taiwanese populations with PD. Early detection and reduction of neuropsychiatric symptoms in people with PD can help decrease caregiver distress.

Neuropsychiatric aspects of Parkinson disease psychopharmacology: Insights from circuit dynamics

Parkinson disease (PD) is a neurodegenerative disorder with a complex pathophysiology characterized by the progressive loss of dopaminergic neurons within the substantia nigra. Persons with PD experience several motoric and neuropsychiatric symptoms. Neuropsychiatric features of PD include depression, anxiety, psychosis, impulse control disorders, and apathy. In this chapter, we will utilize the National Institutes of Mental Health Research Domain Criteria (RDoC) to frame and integrate observations from two prevailing disease constructions: neurotransmitter anomalies and circuit physiology. When there is available evidence, we posit how unified translational observations may have clinical relevance and postulate importance outside of PD. Finally, we review the limited evidence available for pharmacologic management of these symptoms.

[11 C]raclopride positron emission tomography study of dopamine-D2/3 receptor binding in patients with severe major depressive episodes before and after electroconvulsive therapy and compared to control subjects

AIM

The aim of the study was to test: (i) if D₂ /D₃ binding in three functional subsections of striatum is different in patients with severe major depressive episodes than in controls; and (ii) if this difference is normalized after electroconvulsive therapy (ECT).

METHODS

Nine inpatients were examined with positron emission tomography (PET) and the radioligand [¹¹ C]raclopride before and after an average of 8.4 ECT sessions. Treatment response was assessed using the Montgomery-Åsberg Depression Rating Scale. Nine age- and sex-matched controls were examined twice with PET and [¹¹ C]raclopride.

RESULTS

[¹¹ C]raclopride binding was significantly lower in all three subsections of striatum in patients compared to controls (Cohen's d_z , 1.14-1.68; P = 0.003-0.027). Montgomery-Åsberg Depression Ratings decreased significantly after ECT (P < 0.001; Cohen's d_z , 2.9). ECT had no statistically significant effect on [¹¹ C]raclopride binding, although post-ECT binding estimates were more similar to those obtained in controls in all subsections of striatum.

CONCLUSION

Using PET and [¹¹ C]raclopride, we found support for the notion that severe major depressive episodes are associated with significantly lower dopamine D₂ /D₃ binding in all three subsections of striatum compared to controls. We noted no significant effect on D₂ /D₃ binding in the patient group after response to ECT.

Bright light therapy with a head-mounted device for anxiety, depression, sleepiness and fatigue in patients with Parkinson's disease

The beneficial effects of bright light therapy (BLT) on the disabling non-motor symptoms of Parkinson's disease (PD) remain uncertain. The objective of this study was to investigate if daily BLT, with a head-mounted device (Luminette^®), has a beneficial effect on depression, anxiety, daytime sleepiness and fatigue in patients with PD. In this double-blind, placebo-controlled study, 16 patients with PD were randomized to receive either 1 month of BLT or 1 month of placebo therapy, separated by a 2-week washout period, in a crossover fashion. Patients completed questionnaires for the Hospital Anxiety and Depression Scale (HADS), the Epworth Sleepiness Scale (ESS) and the Fatigue Impact Scale (FIS) before and after each treatment period. The primary outcome measures were changed from baseline in scores between treatment groups. No significant changes were observed in the HADS anxiety scores and FIS scores after BLT and after placebo. The ESS scores decreased non-significantly only after BLT. A post hoc analysis of patients who had baseline ESS scores > 11 revealed a significantly greater decrease in ESS scores after BLT than after placebo. Future studies investigating the effect of BLT on sleepiness could focus specifically on patients with high ESS scores.

Cannabidiol increases the nociceptive threshold in a preclinical model of Parkinson's disease

Medications that improve pain threshold can be useful in the pharmacotherapy of Parkinson's disease (PD). Pain is a prevalent PD's non-motor symptom with a higher prevalence of analgesic drugs prescription for patients. However, specific therapy for PD-related pain are not available. Since the endocannabinoid system is expressed extensively in different levels of pain pathway, drugs designed to target this system have promising therapeutic potential in the modulation of pain. Thus, we examined the effects of the 6-hydroxydopamine- induced PD on nociceptive responses of mice and the influence of cannabidiol (CBD) on 6-hydroxydopamine-induced nociception. Further, we investigated the pathway involved in the analgesic effect of the CBD through the co-administration with a fatty acid amide hydrolase (FAAH) inhibitor, increasing the endogenous anandamide levels, and possible targets from anandamide, i.e., the cannabinoid receptors subtype 1 and 2 (CB1 and CB2) and the transient receptor potential vanilloid type 1 (TRPV1). We report that 6-hydroxydopamine- induced parkinsonism decreases the thermal and mechanical nociceptive threshold, whereas CBD (acute and chronic treatment) reduces this hyperalgesia and allodynia evoked by 6-hydroxydopamine. Moreover, ineffective doses of either FAAH inhibitor or TRPV1 receptor antagonist potentialized the CBD-evoked antinociception while an inverse agonist of the CB1 and CB2 receptor prevented the antinociceptive effect of the CBD. Altogether, these results indicate that CBD can be a useful drug to prevent the parkinsonism-induced nociceptive threshold reduction. They also suggest that CB1 and TRPV1 receptors are important for CBD-induced analgesia and that CBD could produce these analgesic effects increasing endogenous anandamide levels.

Physical activity sustains memory retrieval in dopamine-depleted mice previously treated with L-Dopa

The neurodegenerative disorder Parkinson's disease affects motor abilities as well as cognition. The gold standard therapy is L-Dopa, which mainly restores motor skills. Therefore, we require additional interventions to sustain cognitive functions in Parkinson's disease. The lifestyle intervention "physical activity" improves adult hippocampal neurogenesis and memory but so far, its impact has not been investigated in rodent models for Parkinson's disease previously treated with the standard therapy. We hereby asked whether physical activity serves as a pro-neurogenic and -cognitive stimulus in dopamine-depleted mice previously treated with L-Dopa. Therefore, we injected dopamine-depleted mice with L-Dopa/Benserazide followed either by exercise or by a sedentary lifestyle. We analysed adult hippocampal neurogenesis histologically and assessed spatial memory in the Morris water maze. Furthermore, we investigated the hippocampal and striatal monoaminergic cross-talk. Physical activity prevented memory decline and was linked to a slower dopamine turnover but did not enhance neurogenesis in dopamine-depleted mice previously treated with L-Dopa. In conclusion, physical activity did not develop its full pro-neurogenic potential in mice previously treated with L-Dopa but sustained spatial cognition in Parkinson's disease.

Odorants: a tool to provide nonpharmacological intervention to reduce anxiety during normal and pathological aging

Anxiety disorders represent 1 of the most common classes of psychiatric disorders. In the aging population and for patients with age-related pathology, the percentage of people suffering of anxiety is significantly elevated. Furthermore, anxiety carries with it an increased risk for a variety of age-related medical conditions, including cardiovascular disease, stroke, cognitive decline, and increased severity of motor symptoms in Parkinson's disease. A variety of anxiolytic compounds are available but often carry with them disturbing side effects that impact quality of life. Among nonmedicinal approaches to reducing anxiety, odor diffusion and aromatherapy are the most popular. In this review, we highlight the emerging perspective that the use of odorants may reduce anxiety symptoms or at least potentiate the effect of other anxiolytic approaches and may serve as an alternative form of therapy to deal with anxiety symptoms. Such approaches may be particularly beneficial in aging populations with elevated risk for these disorders. We also discuss potential neural mechanisms underlying the anxiolytic effects of odorants based on work in animal models.

Emergent Functional Network Effects in Parkinson Disease

The hallmark pathology underlying Parkinson disease (PD) is progressive synucleinopathy, beginning in caudal brainstem that later spreads rostrally. However, the primarily subcortical pathology fails to account for the wide spectrum of clinical manifestations in PD. To reconcile these observations, resting-state functional connectivity (FC) can be used to examine dysfunction across distributed brain networks. We measured FC in a large, single-site study of nondemented PD (N = 107; OFF medications) and healthy controls (N = 46) incorporating rigorous quality control measures and comprehensive sampling of cortical, subcortical and cerebellar regions. We employed novel statistical approaches to determine group differences across the entire connectome, at the network-level, and for select brain regions. Group differences respected well-characterized network delineations producing a striking "block-wise" pattern of network-to-network effects. Surprisingly, these results demonstrate that the greatest FC differences involve sensorimotor, thalamic, and cerebellar networks, with notably smaller striatal effects. Split-half replication demonstrates the robustness of these results. Finally, block-wise FC correlations with behavior suggest that FC disruptions may contribute to clinical manifestations in PD. Overall, these results indicate a concerted breakdown of functional network interactions, remote from primary pathophysiology, and suggest that FC deficits in PD are related to emergent network-level phenomena rather than focal pathology.

Transcranial direct current stimulation enhances theory of mind in Parkinson's disease patients with mild cognitive impairment: a randomized, double-blind, sham-controlled study

Background

Parkinson’s Disease (PD) with mild cognitive impairment (MCI) (PD-MCI) represents one of the most dreaded complications for patients with PD and is associated with a higher risk of developing dementia. Although transcranial direct current stimulation (tDCS) has been demonstrated to improve motor and non-motor symptoms in PD, to date, no study has investigated the effects of tDCS on Theory of Mind (ToM), i.e., the ability to understand and predict other people’s behaviours, in PD-MCI.

Methods

In this randomized, double-blind, sham-controlled study, we applied active tDCS over the medial frontal cortex (MFC) to modulate ToM performance in twenty patients with PD-MCI. Twenty matched healthy controls (HC) were also enrolled and were asked to perform the ToM task without receiving tDCS.

Results

In the patients with PD-MCI, i) ToM performance was worse than that in the HC, ii) ToM abilities were poorer in those with fronto-executive difficulties, and iii) tDCS over the MFC led to significant shortening of latency for ToM tasks.

Conclusions

We show for the first time that active tDCS over the MFC enhances ToM in patients with PD-MCI, and suggest that non-invasive brain stimulation could be used to ameliorate ToM deficits observed in these patients.

Psychiatric Manifestation in Patients with Parkinson's Disease

Parkinson's disease (PD) is the second most common neurodegenerative disorder. Although its major manifestation is motor symptoms, resulting from the loss of dopaminergic neurons in the substantia nigra, psychiatric symptoms, such as depression, anxiety, hallucination, delusion, apathy and anhedonia, impulsive and compulsive behaviors, and cognitive dysfunction, may also manifest in most patients with PD. Given that the quality of life - and the need for institutionalization - is so highly dependent on the psychiatric well-being of patients with PD, psychiatric symptoms are of high clinical significance. We reviewed the prevalence, risk factors, pathophysiology, and treatment of psychiatric symptoms to get a better understanding of PD for improved management.

Mediating Effect of Mutuality on Health-Related Quality of Life in Patients with Parkinson's Disease

The relationship quality, mutuality, has been identified as a protective factor in family care situations, but its role in mediating health-related quality of life (HRQoL) in patients having Parkinson's disease (PD) is not known. Data on patients' and partners' mutuality (MS), motor signs (UPDRS III), non-motor symptoms (NMSQuest), impaired cognition (IQCODE), dependency in activities of daily life (ADL), and HRQoL (PDQ8) were collected from 51 dyads. Structural equation model with manifest variables was applied to explore if the MS score mediated the effect of UPDRS III, NMSQuest, IQCODE, and dependency in ADL on PDQ8. The results suggest that increasing severity of motor and non-motor symptoms decreases patients' mutuality which leads to worse HRQoL. Partners' mutuality mediated the effect of impaired cognition which in turn decreased patients' mutuality. The findings enhance our understanding of how various symptoms may influence PD patients' HRQoL. This may help clinicians to personalize interventions to provide more effective interventions to improve the lives of patients with PD.

Reliability and Validity of the Geriatric Depression Scale in Italian Subjects with Parkinson's Disease

INTRODUCTION

The Geriatric Depression Scale (GDS) is commonly used to assess depressive symptoms, but its psychometric properties have never been examined in Italian people with Parkinson's disease (PD). The aim of this study was to study the reliability and validity of the Italian version of the GDS in a sample of PD patients.

METHODS

The GDS was administered to 74 patients with PD in order to study its internal consistency, test-retest reliability, construct, and discriminant validity.

RESULTS

The internal consistency of GDS was excellent (α = 0.903), as well as the test-retest reliability (ICC = 0.941 [95% CI: 0.886-0.970]). GDS showed a strong correlation with instruments related to the depression (ρ = 0.880) in PD (ρ = 0.712) and a weak correlation with generic measurement instruments (-0.320 < ρ <-0.217). An area under the curve of 0.892 (95% CI 0.809-0.975) indicated a moderate capability to discriminate depressed patients to nondepressed patient, with a cutoff value between 15 and 16 points that predicts depression (sensitivity = 87%; specificity = 82%).

CONCLUSION

The GDS is a reliable and valid tool in a sample of Italian PD subjects; this scale can be used in clinical and research contexts.

mTOR-Related Brain Dysfunctions in Neuropsychiatric Disorders

The mammalian target of rapamycin (mTOR) is an ubiquitously expressed serine-threonine kinase, which senses and integrates several intracellular and environmental cues to orchestrate major processes such as cell growth and metabolism. Altered mTOR signalling is associated with brain malformation and neurological disorders. Emerging evidence indicates that even subtle defects in the mTOR pathway may produce severe effects, which are evident as neurological and psychiatric disorders. On the other hand, administration of mTOR inhibitors may be beneficial for a variety of neuropsychiatric alterations encompassing neurodegeneration, brain tumors, brain ischemia, epilepsy, autism, mood disorders, drugs of abuse, and schizophrenia. mTOR has been widely implicated in synaptic plasticity and autophagy activation. This review addresses the role of mTOR-dependent autophagy dysfunction in a variety of neuropsychiatric disorders, to focus mainly on psychiatric syndromes including schizophrenia and drug addiction. For instance, amphetamines-induced addiction fairly overlaps with some neuropsychiatric disorders including neurodegeneration and schizophrenia. For this reason, in the present review, a special emphasis is placed on the role of mTOR on methamphetamine-induced brain alterations.

Assessment and Management of Neuropsychiatric Symptoms in Parkinson's Disease

Neuropsychiatric symptoms are highly prevalent in Parkinson's disease and associated with decreased quality of life and adverse health outcomes. In this review, the assessment and management of common neuropsychiatric symptoms are discussed: depression, anxiety, psychosis, cognitive impairment, dementia and apathy. Validated assessment scales are now available for the majority of symptoms. Balancing dopaminergic therapy plays an important role in their management as increasing doses of dopaminergic agents might address depression and anxiety related to 'off' phases, non-motor fluctuations and apathy, while dose reduction might alleviate psychotic symptoms. More targeted treatment is possible through medications utilising different pathways. Although efficacy profiles of individual agents require further exploration, antidepressants as a drug class have shown utility in depression and anxiety in Parkinson's disease. Psychological therapies, especially cognitive behavioural approaches, are effective. Pimavanserin allows the treatment of psychosis in Parkinson's disease without directly affecting the dopaminergic and cholinergic system. The cholinergic system is currently the only target in Parkinson's disease dementia, and antagonists of this system, as are many psychotropic drugs, need to be used with caution. Management of apathy largely relies on non-pharmacological strategies adapted from dementia care, with antidepressants being ineffective and the role of stimulant therapy needing further evaluation.

Frequency of non-motor symptoms in Parkinson's disease presenting to tertiary care centre in Pakistan: an observational, cross-sectional study

OBJECTIVE

To determine the frequency of non-motor symptoms (NMS) in patients of Parkinson's disease (PD) presenting to a movement disorder clinic at a tertiary care centre in Pakistan, and how frequency of NMS is different in male and female patients.

STUDY DESIGN

Observational, cross-sectional study.

SETTING

Tertiary care centre.

PARTICIPANTS

Out of 102 patients, 85 were included. Inclusion criteria were patients with PD diagnosed according to the UK Parkinson's Disease Society Brain Bank Clinical Diagnostic Criteria, age ≥18 years, able to give consent and have no difficulty in answering questions. Exclusion criteria were diseases that resemble PD, stroke, dementia, patients unable to provide information and history of antipsychotic use.

RESULTS

The NMSQuest revealed a mean of nearly seven different NMS per patient. Autonomic problems such as constipation (56%) and nocturia (49%) were the most common NMS, while urinary urgency was reported by 35% of patients. Low mood and feeling sad were reported by 47%, whereas feeling anxious/panicky was reported by 36%. Problem with memory was reported by 45% of patients. Feeling of light-headedness and dizziness was reported by 40% of patients. Problems with sexual relationship were reported by 30% of patients. The most common sleep problem was difficulty falling sleep (29%). Pain not related to the musculoskeletal system was reported by 30% of patients. Loss or change in the ability to taste or smell was reported by 29% of patients. The rest of NMS were less than 25% in frequency. Feeling sad or blue, feeling light-headed/dizzy, unexplained pain, unpleasant sensations in the legs, difficulty in swallowing and faecal incontinence were more common in female participants, while problems with sex were more common in male participants.

CONCLUSION

NMS are quite prevalent in PD in our population. Certain NMS are more common in women as compared with men. There is a need for a large-scale study to look for the association of different NMS with sex.

Investigation of metabolic profile of pimavanserin in rats by ultrahigh-performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry

RATIONALE

Pimavanserin, a selective serotonin 2A receptor inverse agonist, is a promising candidate for treating Parkinson's disease psychosis. Our previous study revealed that there might be the presence of extensive metabolites of pimavanserin in rats. However, the metabolic fate of pimavanserin in vivo remains unknown. Thus, it is essential to develop an efficient method to investigate the metabolic profile of pimavanserin in rats. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) to date has the highest mass measurement accuracy and resolution of any mass spectrometry platform.

METHODS

After a single intragastric administration of pimavanserin at a dose of 50 mg kg^-1 , plasma, bile, urine and feces were collected from rats. A novel and efficient strategy was developed to analyze the metabolic profile of pimavanserin in vivo based on ultrahigh-performance liquid chromatography (UHPLC) coupled with FT-ICR-MS.

RESULTS

A total of 23 metabolites were detected and tentatively identified through comparing their mass spectrometry profiles with those of pimavanserin. These metabolites were found in feces (22), bile (21), rat urine (16) and plasma (15). Results demonstrated that metabolic pathways of pimavanserin in rats included dehydrogenation, demethylation, deethylation, depropylation, debutylation, hydroxylation, dihydroxylation and trihydroxylation.

CONCLUSIONS

A total of 22 phase I metabolites of pimavanserin were detected and tentatively identified. This report presents the first study of screening and identification of the metabolites of pimavanserin. The UHPLC/FT-ICR-MS method is a powerful tool for exploring and identifying metabolites in complex biological samples.

Perceptions of balance and falls following a supervised training intervention - a qualitative study of people with Parkinson's disease

PURPOSE

To explore perceptions of balance and falls among people with mild to moderate Parkinson's disease 3 - 12 months following participation in supervised balance training.

MATERIALS AND METHODS

This qualitative study used in-depth individual interviews for data collection among 13 people with Parkinson's disease. Interviews were systematically analyzed using qualitative content analysis with an inductive approach.

RESULTS

Three main themes arose: Falls - avoided and intended highlights the wide spectrum of fall perceptions, ranging from worse-case scenario to undramatized events; Balance identity incorporates how gradual deterioration in balance served as a reminder of disease progression and how identifying themselves as "aware not afraid" helped certain participants to maintain balance confidence despite everyday activity restriction; Training as treatment recounts how participants used exercise as disease self-management with the aim to maintain independence in daily life. Interpretation of the underlying patterns of these main themes resulted in the overarching theme Training as treatment when battling problems with balance and falls.

CONCLUSIONS

Whereas certain participants expressed a fear of falling which they managed by activity restriction, others described being confident in their balance despite avoidance of balance-challenging activities. Training was used as treatment to self-manage disease-related balance impairments in order to maintain independence in daily life. Implication for Rehabilitation People with Parkinson's disease require early advice about the positive effects of physical activity as well as strategies for self-management in order to ease the psychological and physical burden of progressive balance impairment. Fear of falling should be investigated alongside activity avoidance in this group in order to provide a more accurate insight into the scope of psychological concerns regarding balance and falls in everyday life. Certain people with Parkinson's disease define their balance according to activities they continue to participate in, while others who express fear-related activity avoidance require help to adapt balance-challenging activities in order to maintain balance confidence and avoid physical inactivity.

Psychometric properties of the apathy evaluation scale in patients with Parkinson's disease

Parkinson's disease (PD) frequently entails non-motor symptoms, worsening the course of the disease. Apathy is one of the core neuropsychiatric symptoms that has been investigated in recent years; research is however hampered by the limited availability of well-evaluated apathy scales for these patients. We evaluated the psychometric properties of the Apathy Evaluation Scale (AES) in a sample of PD patients. Psychometric properties, convergent and discriminant validity and sensitivity/specificity were evaluated in patients with (n = 582) or without dementia/depression (n = 339). Internal consistency was high in the entire sample as well as in patients without dementia/depression. Correlations were moderate for convergent validity (UPDRS I item 4: motivation). While apathy could be differentiated from cognitive decline, it was related to depression (Geriatric Depression Scale, GDS-15). The overall classification accuracy based on the UPDRS I item 4 was comparable for AES and GDS scores. The AES exhibits good psychometric properties in PD patients with and without dementia and/or depression. Commonly used screenings on the presence of apathy had low detection rates compared to the AES and reflected both apathetic and depressive symptoms. Psychometric evaluation of available instruments will support further research on the clinical relevance of apathy for disease progression and treatment approaches in PD patients.

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.

Treatment of Nonmotor Symptoms in Parkinson's Disease

Nonmotor symptoms (NMS) are integral to Parkinson's disease (PD) and the management can often be challenging. In spite of the growing evidence that NMS have a key impact on the quality of life of patients and caregivers, most clinical trials still focus on motor symptoms as primary outcomes. As a consequence strong evidence-based treatment recommendations for NMS occurring in PD are spare. In this chapter, the current data addressing the treatment of major NMS such as sleep, cognitive and autonomic dysfunction, and depression and anxiety are described.