Predictors of anxiety in early-stage Parkinson's disease - Results from the first two years of a prospective cohort study

Modulation of time in Parkinson's disease: a review and perspective on cognitive rehabilitation

Time cognition is an essential function of human life, and the impairment affects a variety of behavioral patterns. Neuropsychological approaches have been widely demonstrated that Parkinson's disease (PD) impairs time cognitive processing. Many researchers believe that time cognitive deficits are due to the basal ganglia, including the striatum or subthalamic nucleus, which is the pathomechanism of PD, and are considered to produce only transient recovery due to medication effects. In this perspective, we focus on a compensatory property of brain function based on the improved time cognition independent of basal ganglia recovery and an overlapping structure on the neural network based on an improved inhibitory system by time cognitive training, in patients with PD. This perspective may lead to restoring multiple functions through single function training.

Impulse control behaviors and apathy commonly co-occur in de novo Parkinson's disease and predict the incidence of levodopa-induced dyskinesia

OBJECTIVE

Impulse control behaviors (ICBs) and apathy are believed to represent opposite motivational expressions of the same behavioral spectrum involving hypo- and hyperdopaminergic status, but this has been recently debated. Our study aims to estimate the co-occurrence of ICBs and apathy in early Parkinson's disease (PD) and to determine whether this complex neuropsychiatric condition is an important marker of PD prognoses.

METHODS

Neuropsychiatric symptoms, clinical data, neuroimaging results, and demographic data from de novo PD patients were obtained from the Parkinson's Progression Markers Initiative, a prospective, multicenter, observational cohort. The clinical characteristics of ICBs co-occurring with apathy and their prevalence were analyzed. We compared the prognoses of the different groups during the 8-year follow-up. Multivariate Cox regression analysis was conducted to predict the development of levodopa-induced dyskinesia (LID) using baseline neuropsychiatric symptoms.

RESULTS

A total of 422 PD patients and 195 healthy controls (HCs) were included. In brief, 87 (20.6 %) de novo PD patients and 37 (19.0 %) HCs had ICBs at baseline. Among them, 23 (26.4 %) de novo PD patients and 3 (8.1 %) HCs had clinical symptoms of both ICBs and apathy. The ICBs and apathy group had more severe non-motor symptoms than the isolated ICBs group. Cox regression analysis demonstrated that the co-occurrence of ICBs and apathy was a risk factor for LID development (HR 2.229, 95 % CI 1.209 to 4.110, p = 0.010).

CONCLUSIONS

Co-occurrence of ICBs and apathy is common in patients with early PD and may help to identify the risk of LID development.

Longitudinal faster anxiety progression of GBA variant carriers in the early Parkinson's disease cohort

Objective

Anxiety symptoms are prevalent neuropsychiatric manifestations in Parkinson's disease (PD) and impact the development of motor complications. Our aim was to evaluate the association of GBA variants with the anxiety development in early PD cohort.

Methods

This cohort study used data from the Parkinson Progression Marker Initiative. The primary outcome anxiety was assessed by State-Trait Anxiety Inventory (STAI). The association between GBA and longitudinal change in the STAI total score was examined using linear mixed-effects model, and the association between GBA and anxiety progression was examined using Cox survival analysis.

Results

A total of 385 patients with PD were included in this study, 39 of them were GBA variant carriers and 346 were idiopathic PD without GBA variants. Patients with GBA variants had faster annual increase in anxiety score (β = 0.44; 95% CI, 0.18 to 0.71; p < 0.001) and were at higher risk of anxiety progression (HR 1.87; 95% CI, 1.03 to 3.41; p = 0.03,). Higher baseline scores for Scales for Outcomes in Parkinson's Disease-Autonomic (SCOPA-AUT), which indicated the autonomic dysfunction, also independently predicted faster increase in anxiety score (β = 0.48; 95%CI, 0.19 to 0.69; p < 0.001) and higher incidence of anxiety development (HR = 1.05; 95% CI, 1.01 to 1.08; p = 0.008).

Interpretation

These findings suggest that longitudinal anxiety symptoms worsening was faster in PD patients who were GBA variant carriers and have dysautonomia, and this association was enhanced if they have both.

Association of Neuropsychiatric Symptom Profiles With Cognitive Decline in Patients With Parkinson Disease and Mild Cognitive Impairment

BACKGROUND AND OBJECTIVES

Neuropsychiatric symptoms (NPS) are closely associated with cognitive decline in patients with Parkinson disease (PD). We investigated which profiles of NPS are associated with the risk of dementia in PD with mild cognitive impairment (PD-MCI).

METHODS

We retrospectively assessed 338 patients with PD-MCI from a single tertiary hospital, who underwent neuropsychological tests and a neuropsychiatric inventory (NPI) questionnaire. We conducted a factor analysis of the dichotomized presence of 12 NPI symptoms, yielding 3 NPI factors: factor 1, mood symptoms; factor 2, hyperactivity-related symptoms; and factor 3, psychotic symptoms. Factor analysis of the severity of NPI symptoms also identified similar NPI factors. The neuropsychiatric correlates of NPI factors were evaluated using general linear models for cognitive tests. Subsequently, we evaluated the hazard ratio (HR) of NPI factors on conversion to dementia.

RESULTS

A higher prevalence factor 1 score was associated with lower scores in the verbal memory (β = -0.15; 95% CI -0.24 to -0.06; p = 0.001) and executive domains (β = -0.16; 95% CI -0.28 to -0.04; p = 0.007), whereas higher severity factor 2 scores were associated with lower scores in the naming (β = -0.16; 95% CI -0.28 to -0.03; p = 0.012), visuospatial (β = -0.24; 95% CI -0.41 to -0.07; p = 0.005), and verbal memory domains (β = -0.15; 95% CI -0.24 to -0.05; p = 0.005). A higher severity factor 3 score was associated with lower scores in the visuospatial domain (β = -0.25; 95% CI -0.46 to -0.07; p = 0.007). Cox regression models demonstrated that the risk of dementia was increased in those with higher prevalence factor 1 (HR = 1.48, 95% CI 1.17-1.88, p = 0.001) and factor 2 scores (HR = 1.27, 95% CI 1.07-1.51, p = 0.007) and severity factor 3 score (HR = 1.52, 95% CI 1.29-1.80, p < 0.001) after adjusting for age, sex, education, disease duration, scores for cognition and parkinsonism, and levodopa equivalent dose.

DISCUSSION

This study demonstrated that a higher burden of NPS is associated with dementia conversion in patients with PD-MCI.

Development of anxiety in early Parkinson's disease: A clinical and biomarker study

BACKGROUND

Anxiety affects approximately 40% of Parkinson's disease (PD) patients. However, little is known about its predictors and development over time.

OBJECTIVE

To identify the clinical factors and biomarkers associated with development of anxiety in patients with newly diagnosed PD, and to test which risk factors predict increases in anxiety over time.

METHODS

Data from the Parkinson's Progression Markers Initiative (PPMI) were utilized. The primary outcome was the State-Trait Anxiety Inventory (STAI). Covariates were demographics, motor and non-motor symptoms, cognitive functions, dopamine transporter imaging data, and cerebrospinal fluid (CSF) biomarkers. We examined the association of risk factors at baseline and over 4 years with changes in anxiety scores over time.

RESULTS

A total of 252 patients met the inclusion criteria (mean age: 61.36 years, SD 9.53). At year 4, 42 patients had developed anxiety. Baseline predictors of increase in anxiety scores were greater autonomic dysfunction, dysexecutive function, CSF t-tau levels, excessive daytime sleepiness, and lower olfactory function scores but not motor scores. Over 4 years, change in anxiety scores correlated with deterioration in overall cognitive function, excessive daytime sleepiness, as well as depression and disability, and to a lesser degree worsening of Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) motor scores and caudate dopaminergic uptake changes.

CONCLUSIONS

These findings suggest that development of anxiety in PD is not primarily based on a dopaminergic deficit in the basal ganglia but related to non-dopaminergic or extrastriatal pathology. Early dysexecutive function predicts development of anxiety but increase in anxiety levels correlates most strongly with more global cognitive decline.

Machine learning within the Parkinson's progression markers initiative: Review of the current state of affairs

The Parkinson's Progression Markers Initiative (PPMI) has collected more than a decade's worth of longitudinal and multi-modal data from patients, healthy controls, and at-risk individuals, including imaging, clinical, cognitive, and 'omics' biospecimens. Such a rich dataset presents unprecedented opportunities for biomarker discovery, patient subtyping, and prognostic prediction, but it also poses challenges that may require the development of novel methodological approaches to solve. In this review, we provide an overview of the application of machine learning methods to analyzing data from the PPMI cohort. We find that there is significant variability in the types of data, models, and validation procedures used across studies, and that much of what makes the PPMI data set unique (multi-modal and longitudinal observations) remains underutilized in most machine learning studies. We review each of these dimensions in detail and provide recommendations for future machine learning work using data from the PPMI cohort.

Predictors of anxiety in Parkinson's disease: results from a 3-year longitudinal cohort study

INTRODUCTION

Anxiety symptoms are the most common neuropsychiatric manifestation of Parkinson's disease (PD), contributing to decreased quality of life. Few longitudinal studies in PD samples have examined correlates of anxiety symptoms over time. Understanding predictor variables may help to identify novel targets for reducing anxiety in PD. The aim of this study was to identify predictors of anxiety symptoms over 3 years in a clinic-based PD cohort.

METHODS

Our cohort included patients with PD at an academic medical center in the Southeastern United States (n = 105). Visits included assessment of motor, psychiatric, and cognitive features, including neuropsychological testing. For our multivariate model, we selected 11 predictor variables with the most existing evidence or theoretical support for an association with anxiety symptoms in PD. Multivariate linear mixed model regression was performed to determine which variables were significantly associated with anxiety symptoms over time.

RESULTS

Over half of participants (57%) met the screening threshold for an anxiety disorder at some point during the study. Independent predictors of anxiety symptoms over time included symptoms of REM sleep behavior disorder (RBD) and dysautonomia.

DISCUSSION

In this PD sample, RBD and dysautonomia symptoms were significantly associated with anxiety symptoms over time. Each of these relationships has been reported in one of two prior longitudinal studies. Unlike prior studies, cognitive impairment was not a significant predictor of anxiety symptoms in our sample. Future research should confirm the direction and mechanisms underlying these relationships, including the potential for anxiety symptom reduction through treatment for RBD and dysautonomia.

Depression in Patients with Parkinson's Disease: Current Understanding of its Neurobiology and Implications for Treatment

Depression is one of the most frequent and burdensome non-motor symptoms in Parkinson’s disease (PD), across all stages. Even when its severity is mild, PD depression has a great impact on quality of life for these patients and their caregivers. Accordingly, accurate diagnosis, supported by validated scales, identification of risk factors, and recognition of motor and non-motor symptoms comorbid to depression are critical to understanding the neurobiology of depression, which in turn determines the effectiveness of dopaminergic drugs, antidepressants and non-pharmacological interventions. Recent advances using in vivo functional and structural imaging demonstrate that PD depression is underpinned by dysfunction of limbic networks and monoaminergic systems, depending on the stage of PD and its associated symptoms, including apathy, anxiety, rapid eye movement sleep behavior disorder (RBD), cognitive impairment and dementia. In particular, the evolution of serotonergic, noradrenergic, and dopaminergic dysfunction and abnormalities of limbic circuits across time, involving the anterior cingulate and orbitofrontal cortices, amygdala, thalamus and ventral striatum, help to delineate the variable expression of depression in patients with prodromal, early and advanced PD. Evidence is accumulating to support the use of dual serotonin and noradrenaline reuptake inhibitors (desipramine, nortriptyline, venlafaxine) in patients with PD and moderate to severe depression, while selective serotonin reuptake inhibitors, repetitive transcranial magnetic stimulation and cognitive behavioral therapy may also be considered. In all patients, recent findings advocate that optimization of dopamine replacement therapy and evaluation of deep brain stimulation of the subthalamic nucleus to improve motor symptoms represents an important first step, in addition to physical activity. Overall, this review indicates that increasing understanding of neurobiological changes help to implement a roadmap of tailored interventions for patients with PD and depression, depending on the stage and comorbid symptoms underlying PD subtypes and their prognosis.

Relationship between sleep disorders and neuropsychiatric symptoms in Parkinson's disease: A narrative review

Aim: The objective of this narrative review was to describe the versatile links between mental status and sleep in patients with Parkinson's disease. Methods: We searched randomized controlled studies, observational studies, meta-analyses, systematic reviews, and case reports written in English in PubMed during 2015 - 2021. Additionally, to ensure the completeness of the review, a second, more in-depth literature search was performed using the same electronic database with the search inquiries of increased specificity. Results: The information on pathophysiology, epidemiology, clinical features and risk factors was extracted and formed the basis for this review. Despite how widespread sleep disorders in Parkinson's disease are, there is no systematic information about their association with neuropsychiatric symptoms, such as depression, anxiety, impulse control disorders, apathy, cognitive impairment and psychosis. In this review, we described relationships between these non-motor symptoms of Parkinson's disease, their timeline occurrence, gap in knowledge and perspectives for further research. We suppose that early treatment of sleep disorders in patients with Parkinson's disease can reduce the incidence and extent of neuropsychiatric symptoms. Conclusion: We have demonstrated multiple, multidirectional relationships between sleep disorders and neuropsychiatric symptoms. However, some of them remain unexplored. The described knowledge can be applied to further study the possibility of influencing neuropsychiatric symptoms through the correction of sleep disorders in patients with different stages of Parkinson's disease.

Six-Year Follow-Up of Dysphagia in Patients with Parkinson's Disease

The current study sought to examine longitudinal changes of dysphagia in Parkinson's disease, identify predictors of dysphagia aggravation and elucidate the influence of dysphagia on other symptoms in Parkinson's disease patients. Forty-eight patients with Parkinson's disease were enrolled. All patients underwent videofluoroscopic study of swallowing evaluation and a battery of neuropsychological assessments at baseline in 2014 and at follow-up in 2020. We used t-tests or Wilcoxon tests for comparative analysis between patients with/without dysphagia and comparative analysis of longitudinal data. We used Spearman's correlation analysis to examine predictors of dysphagia aggravation, and the Wilcoxon test to compare neuropsychological aggravation between patients with/without dysphagia at baseline. Swallowing function, cognitive function, depression, anxiety, and quality of life were aggravated at follow-up. Dysphagia prevalence increased from 27.08 at baseline to 39.58% at follow-up. Spearman's correlation results showed that dysphagia was more likely to become aggravated in male patients compared with female patients (P = 0.0049). Cognitive impairment at baseline was significantly related to dysphagia aggravation (P = 0.042). Patients with dysphagia at baseline exhibited a significantly greater increase in anxiety scores than patients without dysphagia at baseline (P = 0.021). The results revealed that male sex and cognitive impairment predicted worsening dysphagia in Parkinson's disease patients, and suggested that dysphagia may have a negative impact on anxiety in Parkinson's disease patients. The results highlight the importance of swallowing function screening and necessary instrumental checks, such as videofluoroscopic study of swallowing, in Parkinson's disease patients.

Pareidolia in Parkinson's Disease and Multiple System Atrophy

Pareidolia is a visual illusion of meaningful objects that arise from ambiguous forms embedded in visual scenes. Previous studies showed that pareidolias are frequently observed in patients with Parkinson's disease (PD) as well as dementia with Lewy bodies. However, whether pareidolias are useful for differentiating PD from other neurodegenerative parkinsonism disorders including multiple system atrophy (MSA) is unclear. The noise pareidolia test (NPT) was performed in 40 and 48 patients with PD and MSA, respectively. A receiver operating characteristic (ROC) curve analysis was used to evaluate sensitivity and specificity. Results of neuropsychological tests were also compared between patients with PD with and without pareidolias. Visual hallucinations were present in none of the subjects. Pareidolic response in the NPT was observed in 47.5% and 18.8% of patients with PD and MSA, respectively. The number of pareidolic responses in patients with PD was significantly larger compared with patients with MSA (P=0.001). ROC curve analyses showed the sensitivity and specificity at 33% and 98%, respectively. Among patients with PD, those with pareidolias demonstrated higher State-Trait Anxiety Inventory-state (P=0.044) and State-Trait Anxiety Inventory-trait (P=0.044) than those without pareidolias. Pareidolias can be found in patients with PD without visual hallucinations, and the pareidolia test may be a highly specific test for differentiating PD from MSA. Thus, anxiety may be associated with pareidolias in patients with PD.

Anxiety in Parkinson's Disease: Correlation with Depression and Quality of Life

Introduction  Anxiety is common in patients with Parkinson's disease (PD). Its prevalence ranges from 20 to 40% but despite that, the high prevalence anxiety in PD is often undiagnosed and untreated. This research was aimed to study the pattern of anxiety with regard to its prevalence and risk factors and to establish the association of anxiety with depression and quality of life (QOL) in patients with PD. Methods  A total of 105 patients with PD were prospectively observed. Demographic and clinical variables were recorded and patients were assessed for anxiety (the Parkinson anxiety scale [PAS]), depression (geriatric depression scale [GDS]), and QOL (Parkinson's Disease Questionnaire-39 [PDQ-39]). Multiple forward logistic regression analysis was done for parameters showing association with anxiety. Pearson's correlation was used to calculate the strength of association of depression and QOL with anxiety. Results  Anxiety was present in 56 PD patients (53.3%). Episodic anxiety was noted in 50%, avoidance behavior in 35%, and persistent anxiety in 15% of these patients. There was significant association of anxiety with duration of disease ( p = 0.001), severity ( p < 0.005), levodopa equivalent dose (LED; p = 0.001), and tremor phenotype of PD ( p = 0.004). Anxiety coexisted with depression in 50 patients (79.4%), which was statistically significant in our cohort ( p = 0.001). There was significant linear relationship between the PAS and PDQ-39. Conclusion  Anxiety exerts a negative impact on the QOL as revealed by proportionately worsening PDQ-39 and PAS scores. Screening for anxiety will allow efficient delivery of support and treatment to patients with PD and their families.

The Relationship Between Anxiety Disorders and Parkinson's Disease: Clinical and Therapeutic Issues

PURPOSE OF REVIEW

This paper seeks to describe anxiety's different symptomatologic presentations in Parkinson's disease (PD), its longitudinal course and predictors, as well as its motor and non-motor correlates. It also reviews the available screening tools and different treatment modalities.

RECENT FINDINGS

In PD, longitudinal predictors of anxiety are mostly non-motor non-dopaminergic symptoms. The longitudinal course of anxiety is mainly a stable one. The Parkinson Anxiety Scale and the Geriatric Anxiety Scale are the 2 recommended screening tools. A third of PD patients suffer from an anxiety disorder at any time point. It can precede or follow PD motor symptoms. Anxiety is associated with demographic, disease-related motor and non-motor features. There is a lack of studies evaluating psychotropic treatment of anxiety in PD. Adjustment of dopaminergic treatment is indicated when anxiety is associated with motor fluctuations. DBS can be useful as well as CBT and body-mind interventions.

Stopwatch training improves cognitive functions in patients with Parkinson's disease

Parkinson's disease (PD) impairs various cognitive functions, including time perception. Dysfunctional time perception in PD is poorly understood, and no study has investigated the rehabilitation of time perception in patients with PD. We aimed to induce the recovery of time perception in PD patients and investigated the potential relationship between recovery and cognitive functions/domains other than time perception. Sixty patients with PD (27 females) and 20 healthy controls (10 females) were recruited. The participants underwent a feedback training protocol for 4 weeks to improve the accuracy of subjective spatial distance or time duration using a ruler or stopwatch, respectively. They participated in three tests at weekly intervals, each comprising 10 types of cognitive tasks and assessments. After duration feedback training for 1 month, performance on the Go/No-go task, Stroop task, and impulsivity assessment improved in patients with PD, while no effect was observed after distance feedback training. Additionally, the effect of training on duration production correlated with extended reaction time and improved accuracy in the Go/No-go and Stroop tasks. These findings suggest that time perception is functionally linked to inhibitory systems. If the feedback training protocol can modulate and maintain time perception, it may improve various cognitive/psychiatric functions in patients with PD. It may also be useful in the treatment of diseases other than PD that cause dysfunctions in temporal processing.

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.

The longitudinal associations between cognition, mood and striatal dopaminergic binding in Parkinson's Disease

Cognitive decline and mood symptoms are common in Parkinson's disease (PD). Reductions in striatal dopaminergic binding have been associated with worse cognition and mood. We investigated whether this association persists throughout the disease progression in newly diagnosed PD. Four-year data from Parkinson's Progression Markers Initiative (PPMI) were used. Groups consisted of left and right limb dominantly affected PD patients, and controls. Longitudinal relationships between cognition, mood and striatal binding ratios were assessed by repeated measures correlations. Reduced binding was associated with general cognitive decline in controls, reduced processing speed and increased mood symptoms in PD. Anxiety was associated with striatum only in left limb dominantly affected PD. Dominantly affected limb side did not impact striatum and cognition association. There are longitudinal associations between striatum, processing speed and anxiety. Dopamine transporter availability imaging may have some prognostic value for cognition and mood in PD.

Sensory focused exercise improves anxiety in Parkinson's disease: A randomized controlled trial

Anxiety has been implicated as one of the greatest influences on quality of life in Parkinson’s disease (PD). The etiology of anxiety is unclear, although previous work suggests that anxiety may be linked to sensory deficits that cause uncertainty in movement. Thus, the current study examined whether focusing attention on sensory feedback during goal-based exercise has the potential to provide benefits to anxiety in PD. Thirty-five participants with PD were randomized to either a Sensory Attention Focused Exercise (SAFEx) (i.e. internal focus of attention, n = 18) or Sham Exercise control (i.e. external focus of attention, n = 17) and completed 33 one-hour attention-based exercise sessions over 11-weeks. Before and after the program (pre and post), participants completed the Parkinson Anxiety Scale (PAS) questionnaire. The PAS includes three anxiety sections: persistent, episodic, and avoidance. Changes in the total PAS score and within each section of the PAS were subjected to two-factor mixed repeated measures ANCOVA. Significant group by time interactions demonstrated that from pre to post, total PAS scores (p = 0.007) and episodic anxiety scores (p = 0.010) significantly decreased in the SAFEx group only (ΔTotal PAS = -5.2, F_(1,27) = 5.41, p = 0.028, η_p² = 0.17; ΔEpisodic Score = -1.8, F_(1,27) = 6.89, p = 0.014, η_p² = 0.20). In conclusion, focusing attention on sensory feedback while completing goal-based exercises may provide significant benefits to improving anxiety in PD. As such, sensory attention focused exercise may be a critical adjunct therapy for improving anxiety, and ultimately quality of life in people with PD.

Depressive symptoms precede cognitive impairment in de novo Parkinson's disease patients: Analysis of the PPMI cohort

INTRODUCTION

Nonmotor symptoms, including depression, anxiety, apathy, and cognitive dysfunction, are common in Parkinson's disease (PD). Although a link between mood symptoms and cognitive impairment in PD has been theorized vis-à-vis striatal dopamine depletion, studies have been inconsistent regarding the relationship between mood symptoms and cognitive function. Inconsistencies may reflect the cross-sectional nature of previous studies. The current study examined the bidirectional longitudinal relationship between mood and cognition.

METHOD

Data were obtained from 310 individuals newly diagnosed with PD, who were followed up to 4 years (baseline, 1st, 2nd, 3rd, and 4th annual follow-ups). Apathy, anxiety, depressive symptoms, motor severity, and neurocognitive functioning were assessed at each annual assessment. The longitudinal relationship between apathy, anxiety, depressive symptoms, and cognition was analyzed with multilevel models.

RESULTS

Over the 4-year period, more severe depressive symptoms were related to worse performance on tasks of processing speed, verbal learning, and verbal delayed recall. Additionally, there was a significant Depression × Time interaction, suggesting that individuals with more severe depressive symptoms experience more rapid declines in global cognitive functioning and verbal learning. Apathy and anxiety were not significantly related to performance in any cognitive test. Lagged models revealed that changes in depression precede declines in working memory, verbal learning, delayed verbal recall, and global cognition.

CONCLUSION

Findings suggest depressive symptoms may be a harbinger for future cognitive decline among individuals with PD. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Measuring Anxiety in Patients With Early-Stage Parkinson's Disease: Rasch Analysis of the State-Trait Anxiety Inventory

The State-Trait Anxiety Inventory (STAI), composed of two 20-item subscales (STAI-state and STAI-trait), has been increasingly used to assess anxiety symptoms in patients with Parkinson's disease (PD). However, the clinimetric attributes of the STAI under the statistical framework of the item-response theory (IRT) have not been fully elucidated within this population to date. We performed an IRT-based Rasch analysis of the STAI outcomes of patients with de novo PD from the Parkinson's Progression Markers Initiative database. The unidimensionality, Rasch model fit, scale targeting, separation reliability, differential item functioning, and response category utility of the STAI were statistically evaluated. A total of 326 (209 males, 117 females) patients without cognitive dysfunction were enrolled in our study. The original versions of the STAI-state and STAI-trait had acceptable separation reliability but lacked appropriate response category functioning, exhibited scale off-targeting, and several items demonstrated poor fit to the Rasch model. The response categories were reduced from four to three, and the rescored three-point TASI-trait demonstrated a marked improvement in clinimetric properties without a significant impact on unidimensionality and separation reliability. The rescored three-point version of the STAI-state required the additional removal of four misfitting items in order to improve the Rasch model fit. To our knowledge, this is the first study to assess the measurement properties based on the IRT of the STAI in patients with PD. Our Rasch analysis identified the components requiring possible amendments in order to improve the clinimetric attributes of the STAI.

REM behavior disorder predicts motor progression and cognitive decline in Parkinson disease

Objective

To investigate whether REM sleep behavior disorder (RBD) is associated with worse motor and cognitive decline in Parkinson disease (PD)

Methods

Four-hundred twenty-one drug-naive patients with early-stage PD and 196 controls without PD were included in this study. All participants underwent a [123I]FP-CIT SPECT scan, CSF assessment, 3-tesla MRI, and thorough clinical assessments.

Results

At cross-sectional analyses, patients with PD and probable RBD (PD-RBD) had lower CSF β-amyloid 1–42 (Aβ42) levels and higher total tau to Aβ42 CSF ratio, higher nonmotor symptoms burden, and worse scores on neuropsychological tests of processing speed, visuospatial functioning, and delayed recognition memory compared to patients with PD without RBD. At longitudinal analyses, the presence of RBD was associated with faster motor progression (hazard ratio [HR] = 1.368, 95% confidence Interval [CI] = 1.036–1.806; p = 0.027) and cognitive decline (HR = 1.794, 95% CI = 1.163–2.768; p = 0.008) over 60-month follow-up. The presence of RBD was a predictor for motor progression only in patients with PD who had both low α-synuclein levels and low [123I]FP-CIT uptake in the striatum (HR = 2.091, 95% CI = 1.116–3.918; p = 0.021) and a predictor for cognitive decline only in patients with PD who had both low Aβ42 and low α-synuclein levels (HR = 2.810, 95% CI = 1.462–5.400; p = 0.002). In the population of controls without PD, the presence of RBD was not associated with cognitive decline or any baseline pathologic changes.

Conclusion

The presence of RBD in PD is associated with faster motor progression in patients with greater synuclein and dopaminergic pathology, and with higher risk of cognitive decline in patients with greater synuclein and amyloid pathology. Our findings provide an important direction toward understanding phenotypes and their prognosis in PD.

Accuracy of Rating Scales and Clinical Measures for Screening of Rapid Eye Movement Sleep Behavior Disorder and for Predicting Conversion to Parkinson's Disease and Other Synucleinopathies

Rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by repeated episodes of REM sleep-related vocalizations and/or complex motor behaviors. Definite diagnosis of RBD is based on history and polysomnography, both of which are less accessible due to the lack of trained specialists and high cost. While RBD may be associated with disorders like narcolepsy, focal brain lesions, and encephalitis, idiopathic RBD (iRBD) may convert to Parkinson's disease (PD) and other synucleinopathies in more than 80% of patients and it is to date the most specific clinical prodromal marker of PD. Identification of individuals at high risk for development of PD is becoming one of the most important topics for current PD-related research as well as for future treatment trials targeting prodromal PD. Furthermore, concomitant clinical symptoms, such as subtle motor impairment, hyposmia, autonomic dysfunction, or cognitive difficulties, in subjects with iRBD may herald its phenoconversion to clinically manifest parkinsonism. The assessment of these motor and non-motor symptoms in iRBD may increase the sensitivity and specificity in identifying prodromal PD subjects. This review evaluates the diagnostic accuracy of individual rating scales and validated single items for screening of RBD and the role and accuracy of available clinical, electrophysiological, imaging, and tissue biomarkers in predicting the phenoconversion from iRBD to clinically manifest synucleinopathies.

Glucose-Dependent Insulinotropic Polypeptide Mitigates 6-OHDA-Induced Behavioral Impairments in Parkinsonian Rats

In the present study, the effectiveness of glucose-dependent insulinotropic polypeptide (GIP) was evaluated by behavioral tests in 6-hydroxydopamine (6-OHDA) hemi-parkinsonian (PD) rats. Pharmacokinetic measurements of GIP were carried out at the same dose studied behaviorally, as well as at a lower dose used previously. GIP was delivered by subcutaneous administration (s.c.) using implanted ALZET micro-osmotic pumps. After two days of pre-treatment, male Sprague Dawley rats received a single unilateral injection of 6-OHDA into the medial forebrain bundle (MFB). The neuroprotective effects of GIP were evaluated by apomorphine-induced contralateral rotations, as well as by locomotor and anxiety-like behaviors in open-field tests. Concentrations of human active and total GIP were measured in plasma during a five-day treatment period by ELISA and were found to be within a clinically translatable range. GIP pretreatment reduced behavioral abnormalities induced by the unilateral nigrostriatal dopamine (DA) lesion produced by 6-OHDA, and thus may be a novel target for PD therapeutic development.

Clinical Markers of Anxiety Subtypes in Parkinson Disease

OBJECTIVE

The aim of this work was to investigate marker profiles for proposed anxiety subtypes in Parkinson disease (PD).

METHODS

We used the persistent anxiety, episodic anxiety, and avoidance behavior subscales of the Parkinson Anxiety Scale as dependent variables in multivariable linear regression analyses using a cross-sectional data set of 311 patients with PD. Independent variables consisted of a range of demographic, psychiatric, and disease-specific markers.

RESULTS

In the most parsimonious model of persistent anxiety, higher Hamilton Depression Rating Scale scores, a history of anxiety, fewer years of education, lower Mini-Mental State Examination scores, lower Lawton Instrumental Activities of Daily Living scores, female sex, and complications of therapy (higher Unified Parkinson Disease Rating Scale part IV scores) were all associated with more severe persistent anxiety. Markers associated with more severe episodic anxiety included PD-specific disturbances of activities of daily living, complications of therapy, higher Hamilton Depression Rating Scale scores, female sex, and a history of anxiety. Finally, higher Hamilton Depression Rating Scale scores, a history of anxiety, complications of therapy, and longer disease duration were associated with avoidance behavior. After excluding clinically depressed patients with PD, disease severity and longer disease duration were significantly associated with episodic anxiety, but not with persistent anxiety.

CONCLUSION

Persistent anxiety is mainly influenced by nonspecific markers, while episodic anxiety seems to be more PD-specific compared to persistent anxiety and may be more situational or contextual. These results provide support for possible distinct underlying constructs for anxiety subtypes in PD.

Prevalence and risk factors for depression and anxiety in Chinese patients with Parkinson disease

BACKGROUND

Anxiety and depression are common in Parkinson disease and both are important determinants of quality of life in patients. Several risk factors are identified but few research have investigated general and Parkinson's disease (PD)-specific factors comprehensively. The aim of this work was to explore PD-specific and -non-specific risk factors for PD with depression or anxiety.

METHODS

A cross-sectional survey was performed in 403 patients with PD. Multivariate logistic analysis was used to investigate the prevalence and risk factors for the depression and anxiety in PD. The data of patients included demographic information, medicine history, disease duration, age at onset (AAO), family history, anti-parkinsonism drug, modified Hoehn and Yahr staging (H-Y) stage, scales of motor and non-motor symptoms and substantia nigra (SN) echogenic areas.

RESULTS

403 PD patients were recruited in the study. Depression and anxiety were present in 11.17% and 25.81% respectively. Marital status, tumor, higher Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) II score, dyskinesia, higher Hamilton Anxiety Rating Scale (HARS) score and lower the Parkinson's disease sleep scale (PDSS) score were associated with depression in PD. female gender, higher rapid eye movement behavior disorder Questionnaire-Hong Kong (RBD-HK) score, higher Hamilton Deprssion Rating Scale (HAMD) score, higher the scale for outcomes in PD for autonomic symptoms (SCOPA-AUT)score and larger SN echogenic areas were associated with anxiety. Neither depression nor anxiety was related to any anti-parkinsonism drugs.

CONCLUSIONS

The prevalence of depression and anxiety in the current PD patients was 11.17% and 25.81% respectively. Disease of tumor, currently having no partner, severer motor function, dyskinesia, poorer sleep quality and anxiety were risk factors for PD with depression. Female, depression, rapid eye movement behavior disorder (RBD), autonomic dysfunction and larger SN area were risk factors for PD with anxiety.