A profile of neuropsychiatric problems and their relationship to quality of life for Parkinson's disease patients without dementia

Neurocognitive functioning of patients with early-stage Parkinson's disease

Parkinson's disease (PD) is a neurological disorder commonly associated with motor deficits. However, cognitive impairment is also common in patients with PD. Cognitive concerns in PD may affect multiple domains of neurocognition and vary across different stages of the disease. Extant research has focused mainly on cognitive deficits in middle to late stages of PD, whereas few studies have examined the unique cognitive profiles of patients with early-stage PD. This study addressed this gap in the published literature and examined neurocognitive functioning and functional capacity of patients with de novo PD, focusing on the unique pattern of cognitive deficits specific to the early stage of the disease. Results indicated that the pattern of cognitive deficits in patients with PD (n = 55; mean age = 72.93) was significantly different from healthy controls (n = 59; mean age = 71.88). Specifically, tasks related to executive functioning, attention, and verbal memory demonstrated the most pronounced deficits in patients with early-stage PD. Clinical implications of these findings are discussed.

Lateral habenula 5-HT1B receptors are involved in regulation of anxiety-like behaviors in parkinsonian rats

Although the output of the lateral habenula (LHb) controls the activity of midbrain dopaminergic and serotonergic systems, which are implicated in the pathophysiology of anxiety, it is not clear the role of LHb 5-HT1B receptors in regulation of anxiety-like behaviors, particularly in Parkinson's disease-related anxiety. In this study, unilateral 6-hydroxydopamine lesions of the substantia nigra pars compacta in rats induced anxiety-like behaviors, led to decreased normalized δ power and increased normalized θ power in the LHb, and decreased dopamine (DA) level in the prelimbic cortex (PrL) compared with sham rats. Down-regulation of LHb 5-HT1B receptors by RNA interference produced anxiety-like effects, decreased normalized δ power and increased normalized θ power in the LHb in both sham and lesioned rats. Further, intra-LHb injection of 5-HT1B receptor agonist CP93129 induced anxiolytic-like responses, increased normalized δ power and decreased normalized θ power in the LHb, and increased DA and serotonin (5-HT) release in the PrL; conversely, 5-HT1B receptor antagonist SB216641 produced anxiety-like effects, decreased normalized δ power and increased normalized θ power in the LHb, and decreased DA and 5-HT release in the PrL in sham and lesioned rats. Additionally, effects of CP93129 and SB216641 on the behaviors, normalized δ and θ power in the LHb, and DA and 5-HT release in the PrL were decreased in lesioned rats, which were consistent with down-regulation of LHb 5-HT1B receptors after DA depletion. Collectively, these findings suggest that 5-HT1B receptors in the LHb are involved in the regulation of anxiety-like behaviors.

Cognitive and executive impairments in Parkinson's disease psychosis: a Bayesian meta-analysis

BACKGROUND

Cognitive and executive deficits lead to worsening of quality of life and are a risk factor for developing dementia in people with Parkinson's disease (PD) with psychosis (PDP). However, which key cognitive domains are differentially affected in PDP compared with those without (PDnP), remains unclear. Here, we examined this using a Bayesian meta-analytical approach.

METHODS

Searches were conducted on PubMed, Web of Science, SCOPUS, Medline and PsycINFO. Hedges' g effect-size estimates were extracted from eligible studies as a measure of standard mean differences between PDP and PDnP participants. Meta-analyses were conducted separately for each cognitive domain and subdomain, we examined the effect of age, PD medications, PD duration and severity, depression and psychosis severity for all major domains with meta-regressions.

RESULTS

Effect-size estimates suggest worse performance on all major domains (k=105 studies) in PDP compared with PDnP participants, with global cognition (k=103 studies, g=-0.57), processing speed (k=29 studies, g=-0.58), executive functions (k=33, g=-0.56), episodic memory (k=30 studies, g=-0.58) and perception (k=34 studies, g=-0.55) as the most likely affected domains. Age, depression and PD duration had moderating effects on task-related performance across most of the major nine domains.

CONCLUSIONS

We report extensive deficits across nine domains as well as subdomains in PD psychosis, with global cognition, processing speed and executive functions as the most likely impaired. The presence of depression may influence task-related performance in PDP, alongside age and PD duration, but not dose of dopamine replacement treatments.

Structural and Functional Imaging Correlates of Visual Hallucinations in Parkinson's Disease

PURPOSE OF REVIEW

To review recent structural and functional MRI studies of visual hallucinations in Parkinson's disease.

RECENT FINDINGS

Previously, neuroimaging had shown inconsistent findings in patients with Parkinson's hallucinations, especially in studies examining grey matter volume. However, recent advances in structural and functional MRI techniques allow better estimates of structural connections, as well as the direction of connectivity in functional MRI. These provide more sensitive measures of changes in structural connectivity and allow models of the changes in directional functional connectivity to be tested. We identified 27 relevant studies and found that grey matter imaging continues to show heterogeneous findings in Parkinson's patients with visual hallucinations. Newer approaches in diffusion imaging and functional MRI are consistent with emerging models of Parkinson's hallucinations, suggesting shifts in attentional networks. In particular, reduced bottom-up, incoming sensory information, and over-weighting of top-down signals appear to be important drivers of visual hallucinations in Parkinson's disease.

5-HT1B receptors in the basolateral amygdaloid nucleus regulate anxiety-like behaviors through AC-PKA signal pathway in a rat model of Parkinson's disease

BACKGROUND

Parkinson's disease (PD) is commonly accompanied with anxiety, multiple studies indicate that the basolateral amygdaloid nucleus (BLA) is closely related to modulation of anxiety and expresses serotonin_1B (5-HT_1B) receptors, however, effects of BLA 5-HT_1B receptors on anxiety-like behaviors are unclear, particularly in PD-related anxiety.

METHODS

The open-field and elevated plus maze tests were used to examine anxiety-like behaviors. In vivo electrophysiology and microdialysis were performed to observe the firing activity of BLA neurons and GABA, glutamate, dopamine (DA) and 5-HT release in the BLA, respectively. Western blotting was used to analyze protein expression of 5-HT_1B receptors, adenylate cyclase (AC) and phosphorylated protein kinase A at threonine 197 site (p-PKA-Thr197) in the BLA.

RESULTS

Intra-BLA injection of 5-HT_1B receptor agonist CP93129 produced anxiety-like effects and antagonist SB216641 induced anxiolytic-like responses in sham-operated and 6-hydroxydopamine-lesioned rats. Further, pretreatment with AC inhibitor SQ22536 and PKA inhibitor KT5720 blocked the behavioral effects of CP93129, respectively. Intra-BLA injection of CP93129 increased the firing rate of BLA glutamate neurons and decreased GABA/glutamate ratio and DA and 5-HT levels in the BLA of sham-operated and the lesioned rats, while SB216641 induced the opposite effects. Compared with sham-operated rats, effects of CP93129 and SB216641 on behaviors, electrophysiology and microdialysis were decreased in the lesioned rats, which were associated with decreased expression of 5-HT_1B receptors, AC and p-PKA-Thr197 in the BLA.

CONCLUSION

These findings suggest that 5-HT_1B receptor-AC-PKA signal pathway in the BLA is involved in the regulation of PD-related anxiety.

Utility of the 20-Item Noise Pareidolia Task (NPT-20) for Assessing Visuoperceptual Disturbances Associated with Complex Visual Hallucinations in Parkinson's Disease

Background

Complex visual hallucinations (VH) are a common complication of Parkinson's disease (PD). Recent studies have demonstrated relevance of face pareidolia to VH in PD and Lewy body dementia (LBD).

Objective

This study examined utility of the 20-item Noise Pareidolia Task (NPT-20) in assessing visuoperceptual disturbances associated with VH in PD.

Methods

Retrospective chart review included 46 consecutive PD patients who completed NPT-20 during clinical neuropsychological evaluation.

Results

About half the sample (43%) reported VH. PD with VH made significantly more false-positive pareidolia errors on the NPT-20 (p < 0.0001). A cut-off of 2 errors yielded 40% sensitivity, 100% specificity to VH; cut-off of 1 yielded 75% sensitivity, 81% specificity. NPT-20 was not associated with any other clinical or demographic factor. Across groups, NPT-20 evinced moderate correlations with visuospatial functioning and visual memory.

Conclusions

Current findings support utility of the NPT-20 for evaluating visuoperceptual disturbances associated with VH in PD.

Changes in both top-down and bottom-up effective connectivity drive visual hallucinations in Parkinson's disease

Visual hallucinations are common in Parkinson's disease and are associated with a poorer quality of life and a higher risk of dementia. An important and influential model that is widely accepted as an explanation for the mechanism of visual hallucinations in Parkinson's disease and other Lewy body diseases is that these arise due to aberrant hierarchical processing, with impaired bottom-up integration of sensory information and overweighting of top-down perceptual priors within the visual system. This hypothesis has been driven by behavioural data and supported indirectly by observations derived from regional activation and correlational measures using neuroimaging. However, until now, there was no evidence from neuroimaging for differences in causal influences between brain regions measured in patients with Parkinson's hallucinations. This is in part because previous resting-state studies focused on functional connectivity, which is inherently undirected in nature and cannot test hypotheses about the directionality of connectivity. Spectral dynamic causal modelling is a Bayesian framework that allows the inference of effective connectivity-defined as the directed (causal) influence that one region exerts on another region-from resting-state functional MRI data. In the current study, we utilize spectral dynamic causal modelling to estimate effective connectivity within the resting-state visual network in our cohort of 15 Parkinson's disease visual hallucinators and 75 Parkinson's disease non-visual hallucinators. We find that visual hallucinators display decreased bottom-up effective connectivity from the lateral geniculate nucleus to primary visual cortex and increased top-down effective connectivity from the left prefrontal cortex to primary visual cortex and the medial thalamus, as compared with non-visual hallucinators. Importantly, we find that the pattern of effective connectivity is predictive of the presence of visual hallucinations and associated with their severity within the hallucinating group. This is the first study to provide evidence, using resting-state effective connectivity, to support a model of aberrant hierarchical predictive processing as the mechanism for visual hallucinations in Parkinson's disease.

Somatoform Symptoms in Parkinson Disease

BACKGROUND

Co-occurring somatoform symptoms complicate the diagnosis and treatment of Parkinson disease (PD).

OBJECTIVE

To learn more about the relationship between somatoform symptoms and PD by comparing demographic and clinical features across PD groups differing in somatoform symptom severity.

METHOD

Using standardized Brief Symptom Inventory-18 (BSI-18) scores to measure somatoform symptom severity, we assigned 1093 individuals with PD to one of four subgroups using comparisons to normative means: low (M < -½ SD), average (M ± ½ SD), high (M +½ SD to +1 SD), very high (M > +1 SD). We used demographics and disease severity measures to assess each subgroup.

RESULTS

Most of the individuals with PD (56%) had high or very high somatoform symptom levels. Increased somatoform symptom levels were associated with female gender, lower socioeconomic status, greater disease duration, increased PD severity (Total Unified Parkinson's Disease Rating Scale), greater disability (Older Americans Resource and Services Disability subscale), increased BSI-18 Depression and Anxiety subscale scores, lower cognitive function (Mini-Mental State Examination), lower self-efficacy scores (Self-Efficacy to Manage Chronic Disease Scale), lower quality of life scores (SF-12 Health Status Survey), and greater medical comorbidity (Cumulative Illness Rating Scale-Geriatrics) (all comparisons: P < 0.001). We found no significant between-group differences for age, race, or marital status.

CONCLUSION

Somatoform symptom severity in individuals with PD is associated with greater PD severity and disability and is more common in females and in individuals with low socioeconomic status. Greater awareness of somatoform symptoms should help improve PD treatment.

The pathobiological basis of depression in Parkinson disease: challenges and outlooks

Depression, with an estimated prevalence of about 40% is a most common neuropsychiatric disorder in Parkinson disease (PD), with a negative impact on quality of life, cognitive impairment and functional disability, yet the underlying neurobiology is poorly understood. Depression in PD (DPD), one of its most common non-motor symptoms, can precede the onset of motor symptoms but can occur at any stage of the disease. Although its diagnosis is based on standard criteria, due to overlap with other symptoms related to PD or to side effects of treatment, depression is frequently underdiagnosed and undertreated. DPD has been related to a variety of pathogenic mechanisms associated with the underlying neurodegenerative process, in particular dysfunction of neurotransmitter systems (dopaminergic, serotonergic and noradrenergic), as well as to disturbances of cortico-limbic, striato-thalamic-prefrontal, mediotemporal-limbic networks, with disruption in the topological organization of functional mood-related, motor and other essential brain network connections due to alterations in the blood-oxygen-level-dependent (BOLD) fluctuations in multiple brain areas. Other hypothetic mechanisms involve neuroinflammation, neuroimmune dysregulation, stress hormones, neurotrophic, toxic or metabolic factors. The pathophysiology and pathogenesis of DPD are multifactorial and complex, and its interactions with genetic factors, age-related changes, cognitive disposition and other co-morbidities awaits further elucidation.

Predictors of health-related quality of life in Parkinson's disease: the impact of overlap between health-related quality of life and clinical measures

PURPOSE

This study aimed to determine predictors of health-related quality of life (HRQoL) in Parkinson's disease (PD) and to explore their predictive value before and after controlling overlapping items between HRQoL and clinical variables.

METHODS

One hundred and eight PD patients underwent motor, anxiety, depression, apathy, fatigue, and neurocognition assessment. HRQoL was assessed by the Parkinson's Disease Questionnaire-39 (PDQ-39). In order to determine predictors of HRQoL in PD, stepwise multiple regression analyses were performed in two ways: before and after removing the emotional well-being dimension from PDQ-39 to control the overlap between depression and anxiety, and HRQoL.

RESULTS

HRQoL total index was predicted by anxiety, fatigue, motor symptoms, and depression, explaining 26.9%, 7.2%, 2.8%, and 1.9% of the variance. However, after removing overlapping items, HRQoL total index was predicted by fatigue (16.5%), anxiety (6.1%), motor symptoms (3.9%), and neurocognition (2.5%), but not depression. Regarding HRQoL dimensions, mobility and activities of daily living were predicted by fatigue (19.7% and 5%) and UPDRS-III (4% and 10.2%); emotional well-being by fatigue (7.9%); social support by anxiety (12.2%) and UPDRS-III (8.6%); communication by neurocognition (5.3%) and UPDRS-III (3.4%); cognition by anxiety (10.6%) and bodily discomfort by anxiety (23%) and fatigue (4.1%).

CONCLUSION

These findings showed the importance of identifying and controlling overlapping items of HRQoL and clinical measures to perform an accurate interpretation. HRQoL dimensions showed different predictors before and after controlling the overlap. Based on these results fatigue, anxiety, motor symptoms, and neurocognition, but not depression are the main predictors of HRQoL in PD patients.

Changes in dynamic transitions between integrated and segregated states underlie visual hallucinations in Parkinson's disease

Hallucinations are a core feature of psychosis and common in Parkinson's. Their transient, unexpected nature suggests a change in dynamic brain states, but underlying causes are unknown. Here, we examine temporal dynamics and underlying structural connectivity in Parkinson's-hallucinations using a combination of functional and structural MRI, network control theory, neurotransmitter density and genetic analyses. We show that Parkinson's-hallucinators spent more time in a predominantly Segregated functional state with fewer between-state transitions. The transition from integrated-to-segregated state had lower energy cost in Parkinson's-hallucinators; and was therefore potentially preferable. The regional energy needed for this transition was correlated with regional neurotransmitter density and gene expression for serotoninergic, GABAergic, noradrenergic and cholinergic, but not dopaminergic, receptors. We show how the combination of neurochemistry and brain structure jointly shape functional brain dynamics leading to hallucinations and highlight potential therapeutic targets by linking these changes to neurotransmitter systems involved in early sensory and complex visual processing.

Evaluation of the Reliability and Validity of the Alzheimer's Disease-Related Quality of Life Instrument among Older Adults with Cognitive Impairment in Mainland China

The purpose of this study is to examine the reliability and validity of the ADRQL instrument among older adults with cognitive impairment in mainland China. Three hundred older adults with cognitive impairment and their primary family caregivers from Wuhan participated in structured interviews. Cronbach's α and Kuder-Richardson Formula 20 were used to examine internal consistency reliability. Confirmatory factor analysis, Heterotrait-Monotrait ratios, and ordinary least square regression were used to assess the factorial validity, discriminant validity, and criterion validity. The ADRQL had acceptable reliability and validity, which can be used to assess overall quality of life for this population.

Medicare Claims Data Underestimate Hallucinations in Older Adults With Dementia

OBJECTIVE

Administrative claims data are used to study the incidence and outcomes of dementia-related hallucinations, but the validity of International Classification of Diseases (ICD) codes for identifying dementia-related hallucinations is unknown.

METHODS

We analyzed Medicare-linked survey data from 2 nationally representative studies of U.S. older adults (the National Health and Aging Trends Study and the Health and Retirement Study) which contain validated cognitive assessments and a screening question for hallucinations. We identified older adults who had dementia or were permanent nursing home residents, and we combined this with questionnaire responses to define dementia-related hallucinations. Using Medicare claims data, we calculated the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of ICD codes for dementia-related hallucinations overall and within prespecified strata of age, neurologic comorbidity, and health care utilization.

RESULTS

We included 2,337 older adults with dementia in our cohort. Among 3,789 person-years of data, 1,249 (33.0%) had hallucations, and of these 286 had a qualifying ICD code for dementia-related hallucinations or psychosis (sensitivity 22.9%). Of 2,540 person-years of dementia without hallucinations, 284 had a diagnosis code for hallucinations (specificity 88.8%). PPV was 50.2%, and NPV was 70.1%. Sensitivity was greatest (57.0%) among those seeing a psychiatrist. Otherwise, there were no significant differences in sensitivity, specificity, PPV, or NPV by age, neurologic diagnosis, or neurologist care.

CONCLUSION

Dementia-related hallucinations are poorly captured in administrative claims data, and estimates of their prevalence and outcomes using these data are likely to be biased.

Cognition, hallucination severity and hallucination-specific insight in neurodegenerative disorders and eye disease

Introduction: Hallucinations occur across neurodegenerative disorders, with increasing severity, poorer cognition and impaired hallucination-specific insight associated with worse outcomes and faster disease progression. It remains unclear how changes in cognition, temporal aspects of hallucinations, hallucination-specific insight and distress relate to each other.Methods: Extant samples of patients experiencing visual hallucinations were included in the analyses: Parkinson's Disease (n = 103), Parkinson's Disease Dementia (n = 41), Dementia with Lewy Bodies (n = 27) and Eye Disease (n = 113). We explored the relationship between factors of interest with Spearman's correlations and random-effect linear models.Results: Spearman's correlation analyses at the whole-group level showed that higher hallucination-specific insight was related to higher MMSE score (r_s = 0.39, p < 0.001) and less severe hallucinations (r_s = -0.28, p < .01). Linear mixed-models controlling for diagnostic group showed that insight was related to higher MMSE (p < .001), to hallucination severity (p = 0.003), and to VH duration (p = 0.04). Interestingly, insight was linked to the distress component but not the frequency component of severity. No significant relationship was found between MMSE and hallucination severity in these analyses.Conclusion: Our findings highlight the importance of hallucination-specific insight, distress and duration across groups. A better understanding of the role these factors play in VH may help with the development of future therapeutic interventions trans-diagnostically.

Patients with depression in the early stages of Parkinson's disease: A cross-sectional observational study

Background. Depression is one of the most maladaptive manifestations of Parkinson's disease (PD). The relationship between depression and motor, cognitive, and other affective disorders in the early stages of PD remains debatable. Aim. To assess the frequency and severity of depression, to clarify the features of motor, affective disorders, and cognitive functions in patients with depression in the early stages of PD. Materials and methods. We observed 61 patients diagnosed with PD at stages III according to the HoehnYahr scale. The average age was 62.29.6 years, the average duration of PD was 2.51.6 years. Data were analyzed using the Unified PD Scale, the Beck Depression Inventory, the Apathy Scale, the Spielberger Anxiety Inventory, the PD Cognitive Assessment Scale (SCOPA-COG), the digital character substitution test (the symbolsnumbers test), the Montreal the Cognitive Function Assessment Scale (MoCA), the number-to-letter combination test, the Stroop test. Results. Symptoms of depression were detected in 48 (79%) patients with PD; 20 (33%) patients had subdepression, 24 (39%) had moderate and severe depression, and 4 (7%) had severe depression. In patients at stage I PD according to HoehnYahr, the frequency of moderate depression was 28%, at stage II (moderate and severe) 45%, and severe 10%. Patients with depression were characterized by a greater severity of motor symptoms, disturbances in daily activities, anxiety, apathy, as well as a decrease in executive cognitive functions. An inverse correlation was noted between the duration of depressive symptoms and deterioration in performance on tests to assess attention and control cognitive functions. Conclusion. Depression is a characteristic feature of the early stages of PD. Its frequency and severity increase from stage I to stage II of PD. Depression can be considered as an indicator of a more severe course of the disease, the progression of impairments in controlling cognitive functions. The possibility of assessing the prognosis of the course of the disease additionally substantiates the need to diagnose depression in patients with PD in the early stages of the disease.

Longitudinal thalamic white and grey matter changes associated with visual hallucinations in Parkinson's disease

OBJECTIVE

Visual hallucinations are common in Parkinson's disease (PD) and associated with worse outcomes. Large-scale network imbalance is seen in PD-associated hallucinations, but mechanisms remain unclear. As the thalamus is critical in controlling cortical networks, structural thalamic changes could underlie network dysfunction in PD hallucinations.

METHODS

We used whole-brain fixel-based analysis and cortical thickness measures to examine longitudinal white and grey matter changes in 76 patients with PD (15 hallucinators, 61 non-hallucinators) and 26 controls at baseline, and after 18 months. We compared white matter and cortical thickness, adjusting for age, gender, time-between-scans and intracranial volume. To assess thalamic changes, we extracted volumes for 50 thalamic subnuclei (25 each hemisphere) and mean fibre cross-section (FC) for white matter tracts originating in each subnucleus and examined longitudinal change in PD-hallucinators versus non-hallucinators.

RESULTS

PD hallucinators showed white matter changes within the corpus callosum at baseline and extensive posterior tract involvement over time. Less extensive cortical thickness changes were only seen after follow-up. White matter connections from the right medial mediodorsal magnocellular thalamic nucleus showed reduced FC in PD hallucinators at baseline followed by volume reductions longitudinally. After follow-up, almost all thalamic subnuclei showed tract losses in PD hallucinators compared with non-hallucinators.

INTERPRETATION

PD hallucinators show white matter loss particularly in posterior connections and in thalamic nuclei, over time with relatively preserved cortical thickness. The right medial mediodorsal thalamic nucleus shows both connectivity and volume loss in PD hallucinations. Our findings provide mechanistic insights into the drivers of network imbalance in PD hallucinations and potential therapeutic targets.

Blockade of pre-synaptic and post-synaptic GABAB receptors in the lateral habenula produces different effects on anxiety-like behaviors in 6-hydroxydopamine hemiparkinsonian rats

Although the output of the lateral habenula (LHb) controls the activity of midbrain dopaminergic and serotonergic systems, which are implicated in the pathophysiology of anxiety, it is not known how blockade of GABA_B receptors in the region affects anxiety-like behaviors, particularly in Parkinson's disease-related anxiety. In this study, unilateral 6-hydroxydopamine lesions of the substantia nigra pars compacta in rats induced anxiety-like behaviors, led to hyperactivity of LHb neurons and decreased the level of extracellular dopamine (DA) in the basolateral amygdala (BLA) compared to sham-lesioned rats. Intra-LHb injection of pre-synaptic GABA_B receptor antagonist CGP36216 produced anxiolytic-like effects, while the injection of post-synaptic GABA_B receptor antagonist CGP35348 induced anxiety-like responses in both groups. Further, intra-LHb injection of CGP36216 decreased the firing rate of the neurons, and increased the GABA/glutamate ratio in the LHb and release of DA and serotonin (5-HT) in the BLA; conversely, CGP35348 increased the firing rate of the neurons and decreased the GABA/glutamate ratio and release of DA and 5-HT in sham-lesioned and the lesioned rats. However, the doses of the antagonists producing these behavioral effects in the lesioned rats were lower than those in sham-lesioned rats, and the duration of action of the antagonists on the firing rate of the neurons and release of the neurotransmitters was prolonged in the lesioned rats. Collectively, these findings suggest that pre-synaptic and post-synaptic GABA_B receptors in the LHb are involved in the regulation of anxiety-like behaviors, and degeneration of the nigrostriatal pathway up-regulates function and/or expression of these receptors.

Psychiatric Comorbidities Affect the Hospitalization Course of Parkinson's Disease Patients: A Cross-Sectional Inpatient Study

Objectives

We aim to delineate the differences in demographic characteristics and hospitalization outcomes including the severity of illness, hospitalization length of stay (LOS) and cost, utilization of deep brain stimulation (DBS), and disposition in Parkinson’s disease (PD) inpatients with psychiatric comorbidities versus without psychiatric comorbidities.

Methods

We conducted a cross-sectional study using the Nationwide Inpatient Sample (NIS), included 56,844 PD inpatients (age ≥40 years), and subdivided them by inpatients into those without psychiatric comorbidities (N = 38,629) and with psychiatric comorbidities (N = 18,471). We compared the distributions of demographic characteristics and hospitalization outcomes (severity of illness, utilization ofDBS, and disposition) by performing Pearson’s chi-square test, and we measured the differences in continuous variables (i.e., age, LOS, and cost) by using the independent samples t-test. 

Results

A significantly higher proportion of PD inpatients with psychiatric comorbidities were female (44.4%) and white (83%) and had a moderate loss of functioning (48.8%) compared to those without psychiatric comorbidities. PD inpatients with psychiatric comorbidities had an increased mean LOS (4.7 days vs. 3.7 days, P <0.001) but a lower mean cost ($37,445 vs. $ 41,957, P <0.001). Also, there was a significantly lower utilization of DBS in PD inpatients with psychiatric comorbidities (19.2% vs. 26.9%, P <0.001) compared to those without psychiatric comorbidities, and an adverse disposition of transfer to a skilled nursing facility/intermediate care facility (47.1% vs. 39.6%, P <0.001) compared to PD inpatients without psychiatric comorbidities.

Conclusion

Although PD patients with psychiatric comorbidities had a moderate loss of functioning, there was significant underutilization of DBS. Meanwhile, psychiatric comorbidities among PD patients led to increased LOS and transfer to skilled facilities.

Risk factors for minor hallucinations in Parkinson's disease

OBJECTIVES

Minor hallucinations (MHs), including sense of presence, passage hallucinations, and visual illusions, have been reported in Parkinson's disease (PD). Here, we investigated the prevalence and associated risk factors for MHs according to appearance time.

METHODS

Data on the clinical characteristics and the appearance time of MHs for 100 PD patients were collected using a questionnaire and analyzed. MHs were classified into two groups according to the time when MHs appeared: MHs appearing while awake during the daytime (dMHs) and MHs appearing at arousal from sleep during the night or early morning (aMHs).

RESULTS

Thirty-eight patients (38%) experienced MHs. dMHs and aMHs were present in 21 (21%) and 28 patients (28%), respectively. Compared to patients without MHs, patients with dMHs had more severe motor symptoms, longer disease duration, higher levodopa equivalent daily dose (LEDD), and higher rates of cognitive impairment and visual hallucinations during the daytime, whereas patients with aMHs had a higher rate of rapid eye movement sleep behavior disorder (RBD), longer disease duration, higher LEDD, and higher dopamine agonist dosage. Logistic regression analysis showed that cognitive impairment was significantly associated with dMHs (odds ratio (OR) 7.292, p = .001), and that RBD (OR 8.306, p < .001) and LEDD (OR 1.002, p = .049) were significantly associated with aMHs.

CONCLUSIONS

Patients with MHs have different clinical characteristics according to the time when MHs appear. These findings have important clinical and prognostic implications and suggest appropriate therapeutic options for psychotic symptoms.

Mood and emotional disorders associated with parkinsonism, Huntington disease, and other movement disorders

This chapter provides a review of mood, emotional disorders, and emotion processing deficits associated with diseases that cause movement disorders, including Parkinson's disease, Lewy body dementia, multiple system atrophy, progressive supranuclear palsy, corticobasal degeneration, frontotemporal dementia with parkinsonism, Huntington's disease, essential tremor, dystonia, and tardive dyskinesia. For each disorder, a clinical description of the common signs and symptoms, disease progression, and epidemiology is provided. Then the mood and emotional disorders associated with each of these diseases are described and discussed in terms of clinical presentation, incidence, prevalence, and alterations in quality of life. Alterations of emotion communication, such as affective speech prosody and facial emotional expression, associated with these disorders are also discussed. In addition, if applicable, deficits in gestural and lexical/verbal emotion are reviewed. Throughout the chapter, the relationships among mood and emotional disorders, alterations of emotional experiences, social communication, and quality of life, as well as treatment, are emphasized.

Differences in network controllability and regional gene expression underlie hallucinations in Parkinson's disease

Visual hallucinations are common in Parkinson's disease and are associated with poorer prognosis. Imaging studies show white matter loss and functional connectivity changes with Parkinson's visual hallucinations, but the biological factors underlying selective vulnerability of affected parts of the brain network are unknown. Recent models for Parkinson's disease hallucinations suggest they arise due to a shift in the relative effects of different networks. Understanding how structural connectivity affects the interplay between networks will provide important mechanistic insights. To address this, we investigated the structural connectivity changes that accompany visual hallucinations in Parkinson's disease and the organizational and gene expression characteristics of the preferentially affected areas of the network. We performed diffusion-weighted imaging in 100 patients with Parkinson's disease (81 without hallucinations, 19 with visual hallucinations) and 34 healthy age-matched controls. We used network-based statistics to identify changes in structural connectivity in Parkinson's disease patients with hallucinations and performed an analysis of controllability, an emerging technique that allows quantification of the influence a brain region has across the rest of the network. Using these techniques, we identified a subnetwork of reduced connectivity in Parkinson's disease hallucinations. We then used the Allen Institute for Brain Sciences human transcriptome atlas to identify regional gene expression patterns associated with affected areas of the network. Within this network, Parkinson's disease patients with hallucinations showed reduced controllability (less influence over other brain regions), than Parkinson's disease patients without hallucinations and controls. This subnetwork appears to be critical for overall brain integration, as even in controls, nodes with high controllability were more likely to be within the subnetwork. Gene expression analysis of gene modules related to the affected subnetwork revealed that down-weighted genes were most significantly enriched in genes related to mRNA and chromosome metabolic processes (with enrichment in oligodendrocytes) and upweighted genes to protein localization (with enrichment in neuronal cells). Our findings provide insights into how hallucinations are generated, with breakdown of a key structural subnetwork that exerts control across distributed brain regions. Expression of genes related to mRNA metabolism and membrane localization may be implicated, providing potential therapeutic targets.

Cytokine-, Neurotrophin-, and Motor Rehabilitation-Induced Plasticity in Parkinson's Disease

Neuroinflammation and cytokine-dependent neurotoxicity appear to be major contributors to the neuropathology in Parkinson's disease (PD). While pharmacological advancements have been a mainstay in the treatment of PD for decades, it is becoming increasingly clear that nonpharmacological approaches including traditional and nontraditional forms of exercise and physical rehabilitation can be critical adjunctive or even primary treatment avenues. Here, we provide an overview of preclinical and clinical research detailing the biological role of proinflammatory molecules in PD and how motor rehabilitation can be used to therapeutically modulate neuroinflammation, restore neural plasticity, and improve motor function in PD.

On the heterogeneity of depression in Parkinson’s disease

Depression in Parkinson’s disease (PD) is one of the leading manifestations of the disease, which reduces quality of life in patients.

Objective: to compare the clinical features of depression at different stages of PD.

Patients and methods. Examinations were made in 162 PD patients aged 62.14±1.99 years without dementia (PD duration, 5.78±0.58 years; Stage, 2.5±0.6). The Unified PD Rating Scale (UPDRS), the Beck Depression Inventory (BDI), and the Spielberger Inventory, the 16-Item PD Fatigue Scale (PFS-16), and the Starkstein Apathy Scale were examined. Dopaminergic agents (DAAs) were prescribed when movement disorders were insufficiently corrected. Antidepressants were not used during the investigation. The follow-up period was 18 months.

Results and discussion. Depression was detected in 136 (84%) patients. Depression symptoms appeared in 16 (12%) patients within 1–8 years before the onset of motor symptoms (MS), in 37 (27%) in the first 2 years after the onset of MS, in 44 (32%) at Hoehn–Yahr stages 2–3 without motor fluctuations (MFs), and in 39 (29%) at the onset of MF. The most severity of depression was noted in cases of its development at the premotor stage and in the period of MF occurrence. During the follow-up, the manifestations of depression disappeared in 16% of the patients taking a DAA; these were relapsing-remitting in 9%, progressive in 11%, or remained stable in 64%. The patients with depression occurring at the premotor stage had a progressive course of depression and a low DAA efficacy: an increase in severity in 30% of cases despite therapy and a reversal in only 10% of cases (versus 25–45% of those at depression onset in the presence of MS). In cases of depression occurring in the first 2 years after MS onset, its reversal was observed in 45%; the group of patients with depression onset in the presence of MF showed a stable course with slight severity fluctuations in 77.8%.

Conclusion. Depression in PD is a heterogeneous affective disorder. There is a relatively favorable course of depression when the latter occurs in the first two years of MS onset. Along with DAA inefficacy, the more severity of depression is noted when the latter occurs in the premotor phase of PD and at the stage of MF.

Management of psychiatric disorders in Parkinson's disease : Neurotherapeutics - Movement Disorders Therapeutics

Affective disorders (depression and anxiety), psychosis, impulse control disorders, and apathy are common and sometimes disabling psychiatric conditions in Parkinson disease (PD). Psychiatric aspects of PD are associated with numerous adverse outcomes, yet in spite of this and their high frequency, there remains incomplete understanding of epidemiology, presentation, risk factors, neural substrate, and management strategies. Psychiatric features are typically co- or multimorbid, and there is great intra- and interindividual variability in presentation [1]. The neuropathophysiological changes that occur in PD, as well as the association between PD treatment and particular psychiatric disorders, suggest a neurobiological contribution to many psychiatric symptoms. There is evidence that psychiatric disorders in PD are still under-recognized and undertreated, and although psychotropic medication use is common, randomized controlled trials demonstrating efficacy and tolerability are largely lacking. Future research on neuropsychiatric complications in PD should be oriented toward determining modifiable correlates or risk factors, and most importantly, establishing efficacious and well-tolerated treatment strategies.

Genetic risk scores and hallucinations in patients with Parkinson disease

Objective

We examine the hypothesized overlap of genetic architecture for Alzheimer disease (AD), schizophrenia (SZ), and Parkinson disease (PD) through the use of polygenic risk scores (PRSs) with the occurrence of hallucinations in PD.

Methods

We used 2 population-based studies (ParkWest, Norway, and Parkinson's Environment and Gene, USA) providing us with 399 patients with PD with European ancestry and a PD diagnosis after age 55 years to assess the associations between 4 PRSs and hallucinations after 5 years of mean disease duration. Based on the existing genome-wide association study of other large consortia, 4 PRSs were created: one each using AD, SZ, and PD cohorts and another PRS for height, which served as a negative control.

Results

A higher prevalence of hallucinations was observed with each SD increase of the AD-PRS (odds ratio [OR]: 1.37, 95% confidence interval [CI]: 1.03-1.83). This effect was mainly driven by APOE (OR: 1.92, 95% CI: 1.14-3.22). In addition, a suggestive decrease and increase, respectively, in hallucination prevalence were observed with the SZ-PRS and the PD-PRS (OR: 0.77, 95% CI: 0.59-1.01; and OR: 1.29, 95% CI: 0.95-1.76, respectively). No association was observed with the height PRS.

Conclusions

These results suggest that mechanisms for hallucinations in PD may in part be driven by the same genetic architecture that leads to cognitive decline in AD, especially by APOE.

Flickering Stimuli Do Not Reliably Induce Visual Hallucinations in Parkinson's Disease

Visual hallucinations are a common and often distressing feature of Parkinson's disease; they are ephemeral and capricious, making them difficult to study but tend to be more prominent in dim illumination. Flickering stimuli can induce simple hallucinations even in healthy individuals. We tested a stroboscope and an equivalent full-screen flickering stimulus in 16 participants: 7 patients with Parkinson's and habitual visual hallucinations, 6 Parkinson's patients without hallucinations and 3 controls. Both flicker sources induced varied geometrical hallucinations in 4 participants (25%) and complex hallucinations in 1 but neither induced typical Parkinson's-associated hallucinations.

Visual hallucinations in neurological and ophthalmological disease: pathophysiology and management

Visual hallucinations are common in older people and are especially associated with ophthalmological and neurological disorders, including dementia and Parkinson's disease. Uncertainties remain whether there is a single underlying mechanism for visual hallucinations or they have different disease-dependent causes. However, irrespective of mechanism, visual hallucinations are difficult to treat. The National Institute for Health Research (NIHR) funded a research programme to investigate visual hallucinations in the key and high burden areas of eye disease, dementia and Parkinson's disease, culminating in a workshop to develop a unified framework for their clinical management. Here we summarise the evidence base, current practice and consensus guidelines that emerged from the workshop.Irrespective of clinical condition, case ascertainment strategies are required to overcome reporting stigma. Once hallucinations are identified, physical, cognitive and ophthalmological health should be reviewed, with education and self-help techniques provided. Not all hallucinations require intervention but for those that are clinically significant, current evidence supports pharmacological modification of cholinergic, GABAergic, serotonergic or dopaminergic systems, or reduction of cortical excitability. A broad treatment perspective is needed, including carer support. Despite their frequency and clinical significance, there is a paucity of randomised, placebo-controlled clinical trial evidence where the primary outcome is an improvement in visual hallucinations. Key areas for future research include the development of valid and reliable assessment tools for use in mechanistic studies and clinical trials, transdiagnostic studies of shared and distinct mechanisms and when and how to treat visual hallucinations.

Progression of Neuropsychiatric Symptoms over Time in an Incident Parkinson's Disease Cohort (ICICLE-PD)

BACKGROUND

Cross-sectional studies have identified that the prevalence of neuropsychiatric symptoms (NPS) in Parkinson's disease (PD) ranges from 70-89%. However, there are few longitudinal studies determining the impact of NPS on quality of life (QoL) in PD patients and their caregivers. We seek to determine the progression of NPS in early PD.

METHODS

Newly diagnosed idiopathic PD cases (n = 212) and age-matched controls (n = 99) were recruited into a longitudinal study. NPS were assessed using the Neuropsychiatric Inventory with Caregiver Distress scale (NPI-D). Further neuropsychological and clinical assessments were completed by participants, with reassessment at 18 and 36 months. Linear mixed-effects modelling determined factors associated with NPI-D and QoL over 36 months.

RESULTS

Depression, anxiety, apathy and hallucinations were more frequent in PD than controls at all time points (p < 0.05). Higher motor severity at baseline was associated with worsening NPI-D scores over time (β = 0.1, p < 0.05), but not cognition. A higher NPI total score was associated with poorer QoL at any time point (β = 0.3, p < 0.001), but not changed in QoL scores.

CONCLUSION

NPS are significantly associated with poorer QoL, even in early PD. Screening for NPS from diagnosis may allow efficient delivery of better support and treatment to patients and their families.

Pimavanserin versus quetiapine for the treatment of psychosis in Parkinson's disease and dementia with Lewy bodies

INTRODUCTION

Psychosis is common among patients with Parkinson's disease (PD) and dementia with Lewy bodies (DLB). Limited data exist on the most effective therapies.

METHODS

Retrospective cohort study comparing patients with PD or DLB initiated on quetiapine or pimavanserin for psychosis. Primary outcome was time to discontinuation of pimavanserin or quetiapine using Kaplan-Meier survival analysis. We hypothesized the rate of antipsychotic discontinuation would be lower in the pimavanserin group. Subjects were included if the indication for treatment was psychosis and excluded if there was a history of major mental illness or no follow up data were available.

RESULTS

Forty-seven patients were included in the quetiapine cohort and 45 in the pimavanserin cohort. Patients in the pimavanserin cohort were more likely to have a diagnosis of DLB (33% vs. 11%, P = 0.01) and to have been prescribed an antipsychotic previously (62% vs. 6%, P < 0.01); otherwise, the groups were similar. Time to discontinuation analysis, which accounts for efficacy, safety and tolerability, revealed a lower early pimavanserin discontinuation rate and a higher late pimavanserin discontinuation rate (HR < 1 before day 43, HR > 1 after day 43; P = 0.04). There was no difference in mortality in the pimavanserin group compared to the quetiapine group (HR 0.37, 95% CI 0.06 to 2.45; P = 0.88). More individuals had a documented secondary indication for taking quetiapine than pimavanserin (38% vs. 4%; P = 0.001).

CONCLUSION

Accounting for efficacy, safety and tolerability, pimavanserin may be more clinically useful for promptly managing psychosis, while quetiapine may confer additional secondary benefits long-term.

Drug and Disease Effects in Parkinson's Psychosis: Revisiting the Role of Dopamine

Background

Levodopa and dopamine agonists (dopamine replacement therapy [DRT]) are implicated in Parkinson's disease psychosis (PDP), but the relationship between DRT and neurotransmitter dysfunction inherent to PD remains unclear.

Objectives

To examine the relationship between baseline striatal dopamine transporter (DAT) binding in drug‐naïve idiopathic PD, introduction of DRT, or dose change and incident early‐onset PDP.

Methods

Baseline DAT binding was compared between patients with and without incident psychosis (defined here as hallucinations or delusions), controlling for age, sex, baseline cognition, and prospective DRT in the Parkinson's Progression Markers Initiative cohort. Incident illusions were not considered psychosis symptoms.

Results

Of 386 patients, 30 (8%) developed PDP (predominantly hallucinations, mean onset 42 months) and 355 (92%) had either no PDP symptoms (mean follow‐up 64 months) or reported illusions only (111/355, 31%). Incident PDP was associated with reduced baseline striatal DAT binding, controlling for confounders (F_1,377 = 10.9; P = 0.001), but not with a specific DRT regime. A total of 6 patients developed PDP when DRT free. There was no suggestion that PDP onset was coincident with starting levodopa or levodopa dose increase. Incident illusions were not associated with reduced DAT binding.

Conclusion

The findings highlight the role of disease‐related dopamine mechanisms in the pathophysiology of hallucinations in Parkinson's disease alongside medication. It remains to be determined how dopamine mechanisms, medication, and other neurotransmitter systems implicated in PDP interact.

Categorising Visual Hallucinations in Early Parkinson's Disease

BACKGROUND

Visual hallucinations (VHs) are common in Parkinson's disease (PD), with prevalence ranging from 27-50% in cross-sectional cohorts of patients with well-established disease. However, minor hallucinations may occur earlier in the disease process than has been previously reported.

OBJECTIVE

We sought to categorise VHs in a cohort of newly diagnosed PD patients and establish their relationship to other clinical features.

METHODS

Newly diagnosed PD participants (n = 154) were recruited as part of the Incidence of Cognitive Impairment in Cohorts with Longitudinal Evaluation in PD (ICICLE-PD) study. Participants completed the Movement Disorders Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS III), Montreal Cognitive Assessment (MoCA) and Parkinson's Disease Questionnaire (PDQ-39) to assess motor severity, cognition and quality of life (QoL), respectively. VHs were classified using the North East Visual Hallucinations Inventory. Hierarchical regression was used to build predictive models of motor severity, QoL and cognition.

RESULTS

22% (n = 34) of participants experienced recurrent VHs with minor VHs being most frequently reported (64.7% of hallucinators). Complex VHs were present in 32.4% of hallucinating participants. Linear regression showed VHs predicted poorer PDQ-39 and MoCA scores (β= 0.201, p = 0.006 and β= - 0.167, p = 0.01, respectively) but not motor severity (p > 0.05).

CONCLUSIONS

Over a fifth of people with newly diagnosed PD reported recurrent VHs; minor hallucinations were the most common, although a small proportion reported complex VHs. Recurrent VHs were found to be a significant independent predictor of cognitive function and QoL but not motor severity. Our findings highlight the importance of screening for VHs at diagnosis.

Hallucinations, Delusions and Impulse Control Disorders in Parkinson Disease

Psychotic and compulsive symptoms in Parkinson disease are highly prevalent and associated with poor outcomes and greater caregiver burden. When acute, delirium should be ruled out or treated accordingly. When chronic, comorbid systemic illnesses, dementia, and psychiatric disorders should be considered. Reduction and discontinuation of anticholinergics, amantadine, dopamine agonists, and levodopa as tolerated, as well as adjunctive clozapine or quetiapine are frequently effective to manage Parkinson disease psychosis. Pimavanserin appears effective but is not widely available, and more experience is needed. Dopamine agonist discontinuation is usually successful for impulse control disorders, but requires frequent monitoring, documentation, and caregiver involvement.

The Neuropsychiatry of Parkinson Disease: A Perfect Storm

Affective disorders, cognitive decline, and psychosis have long been recognized as common in Parkinson disease (PD), and other psychiatric disorders include impulse control disorders, anxiety symptoms, disorders of sleep and wakefulness, and apathy. Psychiatric aspects of PD are associated with numerous adverse outcomes, yet in spite of this and their frequent occurrence, there is incomplete understanding of epidemiology, presentation, risk factors, neural substrate, and management strategies. Psychiatric features are typically multimorbid, and there is great intra- and interindividual variability in presentation. The hallmark neuropathophysiological changes that occur in PD, plus the association between exposure to dopaminergic medications and certain psychiatric disorders, suggest a neurobiological basis for many psychiatric symptoms, although psychological factors are involved as well. There is evidence that psychiatric disorders in PD are still under-recognized and undertreated and although psychotropic medication use is common, controlled studies demonstrating efficacy and tolerability are largely lacking. Future research on neuropsychiatric complications in PD should be oriented toward determining modifiable correlates or risk factors and establishing efficacious and well-tolerated treatment strategies.

Minor hallucinations in Parkinson disease: A subtle symptom with major clinical implications

OBJECTIVE

Psychosis is one of the most debilitating complications of Parkinson disease (PD). Although research on PD psychosis has been focused on the study of well-structured visual hallucinations (VH), currently accepted National Institute of Neurological Disorders and Stroke-National Institute of Mental Health diagnostic criteria emphasize minor hallucinations (MH) as the most common psychotic phenomena in PD. The objective of this review is to comprehensively describe the clinical and research advances on the understanding of MH and to provide future directions for obtaining further insights into their potential major implications for PD management and prognosis.

METHODS

A PubMed search was done in November 2018 to identify articles on minor psychotic phenomena in PD.

RESULTS

MH often precede the onset of well-structured VH and are associated with other nonmotor symptoms such as REM sleep behavior disorder and depression. The pattern of functional brain connectivity changes associated with MH involve visual-processing areas and attention control networks, which overlap with abnormalities described in patients with well-structured VH. The dysfunction of cortical networks in patients with MH may be an early indicator of a more widespread form of the disease.

CONCLUSION

Although called "minor," MH may have major clinical and prognostic implications. Further research is needed to establish whether MH are associated with a higher risk of disabling psychotic complications, cognitive deterioration, or a more accelerated disease progression. Understanding the early neurobiological underpinnings of MH may provide the background for future studies to identify the progressive dysfunction of neural circuits leading to more severe forms of psychosis in PD.

Impacto dos sintomas de ansiedade na qualidade de vida na doença de Parkinson: uma revisão sistemática

RESUMO Objetivo: Revisar estudos relacionados ao impacto da ansiedade na qualidade de vida em pacientes com doença de Parkinson. Métodos: Trata-se de uma revisão sistemática realizada nos bancos de dados PubMed, Scopus, Web of Science e PsycINFO, com os descritores: “anxiety”, “Parkinson's disease” e “quality of life”. Foram selecionados 20 artigos publicados em inglês e sem limite de tempo. Resultado: A maioria dos estudos demonstrou correlação direta entre ansiedade e qualidade de vida em indivíduos com doença de Parkinson. Apenas dois estudos não encontraram essa associação. A presença de sintomas de ansiedade parece estar relacionada com a gravidade dos sintomas motores, sexo feminino e idade mais jovem, levando a um impacto maior na qualidade de vida. Conclusão: Os artigos analisados mostraram que a ansiedade tem impacto negativo sobre a qualidade de vida de indivíduos com doença de Parkinson.

Assessing the sensitivity and specificity of cognitive screening measures for people with Parkinson's disease

INTRODUCTION

While cognitive impairment is a recognised feature of Parkinson's disease (PD), few studies have evaluated the validity of brief cognitive screening measures compared to a comprehensive neuropsychological assessment. This studies aim was to evaluate the sensitivity and specificity of the Mini-Mental State Examination (MMSE), Modified Mini-Mental State Examination and Dementia Rating Scale (DRS-2) to detect cognitive impairment in individuals with PD.

METHOD

Fifty-eight participants were administered the MMSE, 3MS, DRS-2 and a neuropsychological battery. ROC analyses were conducted to assess their effectiveness in classifying cognitive impairment.

RESULTS

None of the three measures demonstrated good sensitivity or specificity to detect single domain cognitive impairment. For detecting impairment on two or more cognitive domains, the MMSE and DRS-2 yielded excellent sensitivity (88%) and specificity (78% and 76% respectively), at cut-off scores of 28 and 136 respectively. The 3MS demonstrated excellent sensitivity (88%) and good specificity (60%) at cut off score of 94.

CONCLUSION

The MMSE and DRS-2 have excellent discriminant ability to classify multi-domain cognitive impairment in PD, however, their ability to detect more focal cognitive impairment is limited. Given that focal domain may be an indicator that could be useful in early detection of cognitive impairment for people with PD, this finding has implication for the use of these measures as screening tools in clinical practice.

Degeneration of dopaminergic circuitry influences depressive symptoms in Lewy body disorders

Aims

Depression is commonly observed even in prodromal stages of Lewy body disorders (LBD), and is associated with cognitive impairment and a faster rate of cognitive decline. Given the role of dopamine in the development of movement disorders, but also in motivation and reward, we investigated neurodegenerative pathology in dopaminergic circuitry in Parkinson's disease (PD), PD with dementia (PDD) and dementia with Lewy bodies (DLB) patients in relation to depressive symptoms.

Methods

α‐synuclein, hyperphosphorylated tau and amyloid‐beta pathology was assessed in 17 DLB, 14 PDD and 8 PD cases within striatal and midbrain subregions, with neuronal cell density assessed in substantia nigra and ventral tegmental area. Additionally, we used a structural equation modeling (SEM) approach to investigate the extent to which brain connectivity might influence the deposition of pathological proteins within dopaminergic pathways.

Results

A significantly higher α‐synuclein burden was observed in the substantia nigra (P = 0.006), ventral tegmental area (P = 0.011) and nucleus accumbens (P = 0.031) in LBD patients with depression. Significant negative correlations were observed between cell density in substantia nigra with Lewy body (LB) Braak stage (P = 0.013), whereas cell density in ventral tegmental area showed negative correlations with LB Braak stage (P = 0.026) and neurofibrillary tangle Braak stage (P = 0.007).

Conclusions

Dopaminergic α‐synuclein pathology appears to drive depression. Selective targeting of dopaminergic pathways may therefore provide symptomatic relief for depressive symptoms in LBD patients.

Disruption of the default mode network and its intrinsic functional connectivity underlies minor hallucinations in Parkinson's disease

BACKGROUND

Minor hallucinations and well-structured hallucinations are considered in the severity continuum of the psychotic spectrum associated with Parkinson's disease. Although their chronological relationship is largely unknown, the spatial patterns of brain atrophy in these 2 forms of hallucinations partially overlap, suggesting they share similar pathophysiological processes. Functional connectivity studies show that disruption of functional networks involved in perception and attention could be relevant in the emergence of well-structured hallucinations. However, functional neuroimaging studies in patients with isolated minor hallucinations are lacking. The objectives of this study were to explore the structural and functional changes underlying minor hallucinations.

METHODS

We compared patients with (n = 18) and without (n = 14) minor hallucinations using a multimodal structural (gray-matter volume voxel-based morphometry) and functional (seed-to-whole-brain resting-state functional MRI) neuroimaging study.

RESULTS

Coincident with previously described structural changes in well-structured hallucinations in Parkinson's disease, patients with minor hallucinations exhibited gray-matter atrophy with significant voxel-wise differences in visuoperceptual processing areas and core regions of the default mode network. Functional connectivity changes consisted of altered connectivity within the default mode network, reduced negative correlation with task-positive network, and aberrant connectivity between posterior regions of the default mode network and visual-processing areas. These changes are in accordance with the attentional networks hypothesis proposed for well-structured hallucinations.

CONCLUSIONS

Although longitudinal studies are needed to assess the potential role of minor hallucinations as an early clinical biomarker of progression to well-structured hallucinations, the present findings show that the 2 phenomena share similar structural and functional brain correlates. © 2018 International Parkinson and Movement Disorder Society.

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

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

Evaluating psychiatric symptoms in Parkinson's Disease by a clinimetric analysis of the Hopkins Symptom Checklist (SCL-90-R)

Although psychiatric comorbidity in Parkinson's Disease (PD) has often been studied, the individual psychiatric symptoms have rarely been evaluated from a clinimetric point of view in an attempt to measure how much the symptoms have been bothering or distressing the PD patients. The current study is therefore aimed at evaluating from a clinimetric viewpoint the severity of psychiatric symptoms affecting PD patients by using the Hopkins Symptom Checklist (SCL-90-R) to show its measurement-driven construct validity (scalability). The conventional nine SCL-90-R subscales (somatization, obsessive-compulsive, interpersonal sensitivity, depression, anxiety, hostility, phobic anxiety, paranoid ideas, and psychoticism), as well as the clinical most valid subscales from the SCL-28 version (depression, anxiety, interpersonal sensitivity, and neurasthenia) were analysed according to a clinimetric approach by comparing PD patients with a control group from a general population study. Scalability was tested by the non-parametric item response theory model by use of a Mokken analysis. Among the various SCL-90-R or SCL-28 subscales we identified from the clinimetric analysis that the somatization, anxiety, phobic anxiety, psychoticism, and neurasthenia (apathy), as well as the SCL-90-R GSI, were the most impaired psychiatric syndromes reaching a clinically significant effect size above 0.80, whereas the total SCL-28 GSI obtained an effect size of just 0.80. Our clinimetric analysis has shown that patients with PD not only are bothered with diverse somatic symptoms, but also with specific secondary psychiatric comorbidities which are clinically severe markers of impairment in the day-to-day function implying a negative cooping approach.

Influence of Mild Cognitive Impairment, Depression, and Anxiety on the Quality of Life of Patients with Parkinson Disease

Background

Neuropsychiatric symptoms (NPS) and mild cognitive impairment (MCI) are common in Parkinson disease (PD) and have a negative impact on the patient's quality of life (QoL). We aim to describe the effect of NPS and MCI on each other and on QoL.

Methods

Sixteen MCI and 37 non-MCI PD patients completed different self-assessment questionnaires including the Parkinson's Disease Questionnaire (PDQ-39), the Beck Depression Inventory (BD), the Beck Anxiety Inventory (BAI), and the Self-Report Manic Inventory (SRMI). Linear regression with stepwise elimination was used to select the significant predictors of QoL and to control for confounding factors.

Results

The significant linear regression model (R² = 0.68, p ≤ 0.01) revealed significant effects of MCI (p = 0.03), BDI (p ≤ 0.01), BAI (p ≤ 0.01), age (p = 0.03), a trend of SRMI (p = 0.06), and disease duration (p = 0.08) on QoL.

Conclusions

MCI, anxiety, depression, and age decrease QoL in patients with PD. NPS has the main influence in the prediction of QoL in patients with PD, whereas MCI is only of minor importance.

Somatization in Parkinson's Disease: A systematic review

The current systematic review study is aimed at critically analyzing from a clinimetric viewpoint the clinical consequence of somatization in Parkinson's Disease (PD). By focusing on the International Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a comprehensive electronic literature research strategy on ISI Web-of-Science, PsychINFO, PubMed, EBSCO, ScienceDirect, MEDLINE, Scopus, and Google Scholar databases. Out of 2.926 initial records, only a total of 9 studies were identified as clearly relevant and analyzed in this systematic review. The prevalence of somatization in PD has been found to range between 7.0% and 66.7%, with somatoform disorders acting as clinical factor significantly contributing to predict a progressive cognitive impairment. We highlighted that somatization is a highly prevalent comorbidity affecting PD. However, the clinical consequence of such psychiatric symptom should be further evaluated by replacing the clinically inadequate diagnostic label of psychogenic parkinsonism with the psychosomatic concept of persistent somatization as conceived by the Diagnostic Criteria for Psychosomatic Research (DCPR).

Characteristics, correlates, and assessment of psychosis in Parkinson disease without dementia

INTRODUCTION

Considering that psychosis in Parkinson disease (PD) is associated with worse outcomes, including dementia, we aimed to study the characteristics, correlates, and assessment of PD psychosis in those without dementia.

METHODS

101 PD subjects without dementia (Montreal Cognitive Assessment ≥21/30) were recruited to participate in a study of neuropsychiatric symptoms in PD. This study included a baseline standard neurological exam and common PD symptom assessments. Using the Scale for the Assessment of Positive Symptoms (SAPS) and separate assessment of visual illusions and sense of presence, NINDS-NIMH criteria for PD psychosis were applied.

RESULTS

Of the 33 (32.7%) PD subjects who met diagnostic criteria for psychosis in PD, visual illusions were most common (72.7%), followed by visual hallucinations (39.4%). Adjusted for presence of REM sleep behavior disorder (RBD) (p = 0.097), use of dopamine agonists (OR = 3.7, p = 0.012) and greater autonomic symptom burden (OR = 1.1 (per 1-unit change in score on SCOPA-AUT), p = 0.012) were associated with greater risk of psychosis. Use of dopamine agonists (OR = 5.0, p = 0.007), higher MDS-UPDRS Part II score (OR = 1.1, p = 0.010), and presence of RBD (OR = 4.8, p = 0.012) were independent predictors of visual hallucinations and visual illusions. MDS-UPDRS item 1.2 score ≥1 had highly correlated with the SAPS score (r = 0.65, p < 0.0001), but was 42% sensitive and 96% specific for identifying psychosis.

CONCLUSION

This study confirms the association between dopamine agonists and psychosis in PD patients without dementia. The association of RBD, autonomic symptoms, and MDS-UPDRS Part II scores with psychosis underscore its link to brainstem dysfunction and greater PD motor symptom severity.

Quality of Life and Nonmotor Symptoms in Parkinson's Disease

Health-related quality of life (HRQoL) is defined as "the perception and evaluation by patients themselves of the impact caused on their lives by the disease and its consequences." HRQoL is conceptualized as a combination of physical, psychological, and social well-being in the context of a particular disease. Following earlier studies revolving on the impact of the classic motor symptoms of Parkinson's disease on HRQoL, mounting evidence have been produced that nonmotor symptoms (NMS) significantly and independently contribute to worse HRQoL. This holds particularly true for such NMS such as neuropsychiatric disturbances, cognitive impairment, and fatigue, the burden of which might well exceed the effects of the motor symptoms. Nonetheless, there is very sparse evidence on how to manage these NMS and whether targeting NMS would in fact lead to an improvement of HRQoL, which calls for the need of future trials with NMS as primary outcomes.

Psychosis in Parkinson's disease: From the soft signs to the hard science

Patients with Parkinson's disease (PD) may develop a wide spectrum of non-motor symptoms during the course of illness. Psychosis is one such commonly observed non-motor symptoms of PD. Although several studies based on neuroimaging, genetics, retinal imaging, and neuropsychological evaluations have explored the pathogenesis of psychosis in PD; exact neural correlates are yet to be understood. Identification of factors related to psychosis in PD is important, as psychosis has been reported to be associated with higher rates of mortality, caregiver distress, and nursing home placements. This review highlights the potential of the previous studies to gain further insights into the soft signs and hard science related to psychosis in PD. Studies based on neuropsychological evaluations have revealed significant dysfunction in attention, executive and visuospatial functions in patients with PD and psychosis. Neuroimaging studies reveal grey matter atrophy in regions of the brain corresponding to both dorsal and ventral visual pathways, hippocampus, and cholinergic structures. Meanwhile, functional imaging studies suggest existence of an aberrant top-to-bottom visual processing system, which dominates the normal bottom-to-top system in patients with PD and visual hallucinations. Although nucleotide polymorphisms of several genes have been studied in PD patients with psychosis, those on -45C>T polymorphisms of cholecystokinin gene (CCK) have shown the greatest promise because of its association with psychosis in PD. All these taken together, cohesively unfold the current status of research in patients with PD and psychosis. This paper also highlights the missing links and discusses the approach to future research in this field.

The relation of anxiety and cognition in Parkinson's disease

OBJECTIVE

Parkinson's disease (PD) has long been conceptualized as a motor disorder, but nonmotor symptoms also manifest in the disease and significantly reduce quality of life. Anxiety and cognitive dysfunction are prevalent nonmotor symptoms, even in early disease stages, but the relation between these symptoms remains poorly understood. We examined self-reported anxiety and neurocognitive function, indexed by measures of executive function (set-shifting and phonemic fluency), categorical fluency, and attention/working memory. We hypothesized that anxiety would correlate with cognitive performance.

METHOD

The Beck Anxiety Inventory and cognitive tests (Trail Making, Verbal Fluency, Digit Span) were administered to 77 nondemented adults with mild to moderate idiopathic PD (39 men, 38 women; Mage = 62.9 years).

RESULTS

Higher anxiety was associated with more advanced disease stage and severity and with poorer set-shifting when using a derived metric to account for motoric slowing. Depression correlated with greater anxiety and disease severity, but not with cognitive performance.

CONCLUSIONS

Our findings support the association of anxiety with a specific domain of executive function, set-shifting, in nondemented individuals with mild to moderate PD, raising the possibility that treatment of anxiety may alleviate aspects of executive dysfunction in this population. (PsycINFO Database Record

Risk factors for early psychosis in PD: insights from the Parkinson's Progression Markers Initiative

BACKGROUND

Parkinson's Disease (PD) psychosis refers to the spectrum of illusions, formed hallucinations and delusions that occur in PD. Visual hallucinations and illusions are thought to be caused by specific cognitive and higher visual function deficits and patients who develop such symptoms early in the disease course have greater rates of cognitive decline and progression to dementia. To date, no studies have investigated whether such deficits are found prior to the onset of PD psychosis.

METHOD

Here we compare baseline cognitive, biomarker (structural imaging and cerebrospinal fluid) and other PD psychosis risk factor data in patients who go on to develop illusions or hallucinations within 3-4 years of follow-up in the Parkinson's Progression Markers Initiative cohort of newly diagnosed PD.

RESULTS

Of n=423 patients with PD, n=115 (27%) reported predominantly illusions with the median time of onset at 19.5 months follow-up. At study entry these patients had reduced CSF amyloid Aß1-42, lower olfaction scores, higher depression scores and increased REM sleep behaviour disorder symptoms compared to patients without early onset PD psychosis but no differences in cognitive, higher visual or structural imaging measures. A subset of patients with early onset formed hallucinations (n=21) had reduced higher visual function at baseline, cortical thinning in parietal, occipital and frontal cortex and reduced hippocampal volume.

CONCLUSIONS

The findings suggest early onset illusions and formed hallucinations are linked to amyloid pathology in PD and point to a difference in the underlying pathophysiological mechanism of illusions and formed hallucinations, with implications for their respective links to future cognitive decline.