Psychiatric syndromes in Parkinson's disease

The clinical diagnosis of Parkinson's disease

After more than 200 years since its initial description, the clinical diagnosis of Parkinson's disease (PD) remains an often-challenging endeavor, with broad implications that are fundamental for clinical management. Despite major developments in understanding it's pathogenesis, pathological landmarks, non-motor features and potential paraclinical clues, the most accepted diagnostic criteria remain solidly based on a combination of clinical signs. Here, we review this process, discussing its history, clinical criteria, differential diagnoses, ancillary diagnostic testing, and the role of non-motor and pre-motor signs and symptoms.

The effects of treatment with pimavanserin on activities of daily living in patients with Parkinson's disease psychosis: a 16-week, single-arm, open-label study

Background

More than half of patients with Parkinson's disease will experience psychosis symptoms in the form of hallucinations or delusions at some point over the course of their disease. These symptoms can significantly impact patients' health-related quality of life, cognitive abilities, and activities of daily living (ADLs) and function. Clinical assessment of how psychosis impacts these measures is crucial; however, few studies have assessed this sufficiently, in part due to a lack of appropriate scales for comprehensively assessing function.

Objective

The objective was to assess how symptoms of Parkinson's disease psychosis (PDP) impact ADLs and function, cognitive function, and health-related quality of life.

Design

To address this unmet need, we utilized a modified version of the Functional Status Questionnaire (mFSQ) to measure the impact of psychosis on ADLs and function in patients with PDP treated with pimavanserin, a US Food and Drug Administration-approved medication to treat hallucinations and delusions associated with PDP.

Methods

Eligible patients entered a 16-week, single-arm, open-label study of oral pimavanserin (34 mg) taken once daily. The primary endpoint was change from baseline to Week 16 on the mFSQ. Secondary endpoints included the Movement Disorders Society-modified Unified Parkinson's Disease Rating Scale (MDS-UPDRS) I and II; Schwab and England ADL; Clinical Global Impression-Severity of Illness (CGI-S), Clinical Global Impression-Improvement (CGI-I), and Patient Global Impression-Improvement (PGI-I), and were also measured as change from baseline to Week 16 using mixed-effects model for repeated measures (MMRM) and least-squares mean (LSM).

Results

Our results in a proof-of-concept, 16-week, open-label clinical study in 29 patients demonstrated that an improvement in psychosis symptoms following treatment with pimavanserin was associated with improvements in multiple measures of ADLs and function. Notably, a significant improvement was found on the primary endpoint, change from baseline to Week 16 in mFSQ score [LSM [SE] 14.0 [2.50], n = 17; 95% CI (8.8, 19.3); p < 0.0001].

Conclusion

These findings highlight the potential for improvement in function with improvement of psychosis symptoms in patients with PDP and suggest that the mFSQ may be a measurement tool to evaluate the level of improvement in function.

Trial registration

ClinicalTrials.gov Identifier: NCT04292223.

Dimensions of apathy in Parkinson's disease

INTRODUCTION

Apathy is one of the most common neuropsychiatric manifestations in Parkinson's disease (PD). Recent proposals consider apathy as a multidimensional construct, which can manifest in behavioral, cognitive, emotional, and/or social dimensions. Apathy also overlaps conceptually and clinically with other non-motor comorbidities, particularly depression. Whether all of these dimensions are applicable to the apathetic syndrome experienced by people with PD is unclear. In the present study, we investigated the multidimensional pattern of apathy associated with PD, using the recently developed Apathy Motivation Index (AMI) which probes behavioral, emotional, and social apathy dimensions. We then examined the relationship between these dimensions and other features of PD commonly associated with apathy, including depression, anxiety, cognition, and motor state.

METHODS

A total of 211 participants were identified from the New Zealand Brain Research Institute (NZBRI) longitudinal PD cohort. One hundred eight patients and 45 controls completed the AMI, administered as an online questionnaire, and additional assessments including neuropsychiatric, neuropsychological, and motor scores. The pattern of dimensional apathy in PD was assessed using a repeated-measured analysis of variance, while simple linear regressions were performed to evaluate relationships between these dimensions and other variables.

RESULTS

We found a significant interaction between group (PD versus control) and apathy subscale, driven mainly by higher levels of social and behavioral-but not emotional-apathy in those with PD. This result was strikingly similar to a previous study investigating social apathy in PD. Distinct patterns of dimensional apathy were associated with depression and anxiety, with social and behavioral apathy positively associated with depression, and emotional apathy negatively associated with anxiety.

CONCLUSION

This work provides further evidence for a distinct pattern of apathy in people with PD in which deficits manifest in some-but not all-dimensions of motivated behavior. It emphasizes the importance of considering apathy as a multidimensional construct in clinical and research settings.

Targeting G Protein-Coupled Receptors in the Treatment of Parkinson's Disease

Parkinson's disease (PD) is a progressive neurodegenerative disease characterized in part by the deterioration of dopaminergic neurons which leads to motor impairment. Although there is no cure for PD, the motor symptoms can be treated using dopamine replacement therapies including the dopamine precursor L-DOPA, which has been in use since the 1960s. However, neurodegeneration in PD is not limited to dopaminergic neurons, and many patients experience non-motor symptoms including cognitive impairment or neuropsychiatric disturbances, for which there are limited treatment options. Moreover, there are currently no treatments able to alter the progression of neurodegeneration. There are many therapeutic strategies being investigated for PD, including alternatives to L-DOPA for the treatment of motor impairment, symptomatic treatments for non-motor symptoms, and neuroprotective or disease-modifying agents. G protein-coupled receptors (GPCRs), which include the dopamine receptors, are highly druggable cell surface proteins which can regulate numerous intracellular signaling pathways and thereby modulate the function of neuronal circuits affected by PD. This review will describe the treatment strategies being investigated for PD that target GPCRs and their downstream signaling mechanisms. First, we discuss new developments in dopaminergic agents for alleviating PD motor impairment, the role of dopamine receptors in L-DOPA induced dyskinesia, as well as agents targeting non-dopamine GPCRs which could augment or replace traditional dopaminergic treatments. We then discuss GPCRs as prospective treatments for neuropsychiatric and cognitive symptoms in PD. Finally, we discuss the evidence pertaining to ghrelin receptors, β-adrenergic receptors, angiotensin receptors and glucagon-like peptide 1 receptors, which have been proposed as disease modifying targets with potential neuroprotective effects in PD.

Choroid plexus epithelium and its role in neurological diseases

Choroid plexus epithelial cells can secrete cerebrospinal fluid into the ventricles, serving as the major structural basis of the selective barrier between the neurological system and blood in the brain. In fact, choroid plexus epithelial cells release the majority of cerebrospinal fluid, which is connected with particular ion channels in choroid plexus epithelial cells. Choroid plexus epithelial cells also produce and secrete a number of essential growth factors and peptides that help the injured cerebrovascular system heal. The pathophysiology of major neurodegenerative disorders like Alzheimer's disease, Parkinson's disease, as well as minor brain damage diseases like hydrocephalus and stroke is still unknown. Few studies have previously connected choroid plexus epithelial cells to the etiology of these serious brain disorders. Therefore, in the hopes of discovering novel treatment options for linked conditions, this review extensively analyzes the association between choroid plexus epithelial cells and the etiology of neurological diseases such as Alzheimer's disease and hydrocephalus. Finally, we review CPE based immunotherapy, choroid plexus cauterization, choroid plexus transplantation, and gene therapy.

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

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

Antidepressant-Like Properties of Intrastriatal Botulinum Neurotoxin-A Injection in a Unilateral 6-OHDA Rat Model of Parkinson's Disease

Parkinson’s patients often suffer from depression and anxiety, for which there are no optimal treatments. Hemiparkinsonian (hemi-PD) rats were used to test whether intrastriatal Botulinum neurotoxin-A (BoNT-A) application could also have antidepressant-like properties in addition to the known improvement of motor performance. To quantify depression- and anxiety-like behavior, the forced swim test, tail suspension test, open field test, and elevated plus maze test were applied to hemi-PD rats injected with BoNT-A or vehicle. Furthermore, we correlated the results in the forced swim test, open field test, and elevated plus maze test with the rotational behavior induced by apomorphine and amphetamine. Hemi-PD rats did not show significant anxiety-like behavior as compared with Sham 6-OHDA- + Sham BoNT-A-injected as well as with non-injected rats. However, hemi-PD rats demonstrated increased depression-like behaviors compared with Sham- or non-injected rats; this was seen by increased struggling frequency and increased immobility frequency. Hemi-PD rats intrastriatally injected with BoNT-A exhibited reduced depression-like behavior compared with the respective vehicle-receiving hemi-PD animals. The significant effects of intrastriatally applied BoNT-A seen in the forced swim test are reminiscent of those found after various antidepressant drug therapies. Our data correspond with the efficacy of BoNT-A treatment of glabellar frown lines in treating patients with major depression and suggest that also intrastriatal injected BoNT-A may have some antidepressant-like effect on hemi-PD.

Human moral decision-making through the lens of Parkinson's disease

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic neurons in the basal ganglia (BG) and thalamocortical circuitry. While defective motor control has long been considered the defining symptom of PD, mounting evidence indicates that the BG are fundamentally important for a multitude of cognitive, emotional, and motivational processes in addition to motor function. Here, we review alterations in moral decision-making in people with PD, specifically in the context of deceptive behavior. We report that PD patients exhibit two opposite behavioral patterns: hyper- and hypo-honesty. The hyper-honest subgroup engages in deception less often than matched controls, even when lying is associated with a monetary payoff. This behavioral pattern seems to be linked to dopaminergic hypo-activity, implying enhanced harm avoidance, risk aversion, non-impulsivity, and reduced reward sensitivity. On the contrary, the hypo-honest subgroup-often characterized by the additional diagnosis of impulse control disorders (ICDs) and dopamine dysregulation syndrome (DDS)-deceives more often than both PD patients without ICDs/DDS and controls. This behavioral pattern appears to be associated with dopaminergic hyperactivity, which underpins enhanced novelty-seeking, risk-proneness, impulsivity, and reward sensitivity. We posit that these two complementary behavioral patterns might be related to dysfunction of the dopaminergic reward system, leading to reduced or enhanced motivation to deceive. Only a few studies have directly investigated moral decision-making in PD and other neurodegenerative disorders affecting the BG, and further research on the causal role of subcortical structures in shaping moral behavior is needed.

The Impact of Air Pollution on Neurodegenerative Diseases

BACKGROUND

With the development of industrialization in human society, ambient pollutants are becoming more harmful to human health. Epidemiological and toxicological studies indicate that a close relationship exists between particulate matter with a diameter ≤2.5 µm (PM2.5) and neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD). To further confirm the relationship, we focus on possible relevant mechanisms of oxidative stress and neuroinflammation underlying the association between PM2.5 and neurodegenerative diseases in the review.

METHODS

A literature search was performed on the studies about PM2.5 and neurodegenerative diseases via PubMed. A total of 113 articles published were selected, and 31 studies were included.

RESULTS

PM2.5 can enter the central nervous system through 2 main pathways, the blood-brain barrier and olfactory neurons. The inflammatory response and oxidative stress are 2 primary mechanisms via which PM2.5 leads to toxicity in the brain. PM2.5 abnormally activates microglia, inducing the neuroinflammatory process. Inflammatory markers such as IL-1β play an essential role in neurodegenerative diseases such as AD and PD. Moreover, the association between lipid mechanism disorders related to PM2.5 and neurodegenerative diseases has been gaining momentum.

CONCLUSIONS

In conclusion, PM2.5 could significantly increase the risk of neurological disorders, such as AD and PD. Furthermore, any policy aimed at reducing air-polluting emissions and increasing air quality would be protective in human beings.

Depressive symptoms effect subjective sleep quality in Chinese patients with Parkinson's disease

OBJECTIVES

The objective of this paper was aimed to estimate the influence of depressive symptoms on subjective sleep quality in Chinese PD patients.

PATIENTS AND METHODS

A sample of 491 PD patients was collected and studied in the present study. Depressive symptoms were assessed using the Hamilton Rating Scale for Depression (HAMD). PD severity was assessed using Hoehn and Yahr (H-Y) staging, and motor symptoms were measured with the Unified PD Rating Scale (UPDRS) part III. The Montreal Cognitive Assessment (MOCA) was used to evaluate the global Cognitive status and PD Sleep Scale (PDSS) was used to quantify sleep quality. Three linear regression models were built to check factors associated with caregiver burden, one for the total sample and two for subgroups stratified by the presence of cognitive disturbance.

RESULTS

In our sample, 29.9% of patients suffer from sleep disturbance. The most frequent depressive symptoms were helplessness (81.5%), depressed mood (57.8%), and general somatic symptoms (55.4%) for entire sample. Patients with cognitive disturbance (n = 274; 55.8% of sample) presented more depressive symptoms than patients without cognitive disturbance. Patients suffer poorer sleep quality when patients experience depression with cognitive disturbance. On linear regression models, the main determinants of subjective quality for the total sample were NMS-depression/anxiety/anhedonia, HAMD-anxiety/somatization, disease severity, age and HAMD-loss of weight. For patients with cognitive disturbance, the significant determinants were NMS-depression/anxiety/anhedonia, HAMD-anxiety/somatization, motor symptoms, HAMD-loss of weight and gender. For patients without cognitive disturbance, the significant determinants were NMS-depression/anxiety/anhedonia, disease severity and HAMD-anxiety/somatization.

CONCLUSION

Depressive symptoms in PD are highly associated with and are determinants of subjective sleep quality, and are more prevalent in patients with cognitive disturbance. Detailed assessment and specific interventions aimed at depression and dementia could alleviate sleep disorder.

Relationships between activity and well-being in people with parkinson's disease

OBJECTIVES

The complex symptomatology of Parkinson' disease (PD) usually goes along with reduced physical activity. Previous studies have indicated positive effects of activating therapies on patients' well-being. This study, therefore, examined how activity in daily life is related to patients' subjective condition.

MATERIALS AND METHODS

Twenty-one PD patients rated their condition every two hours during two routine days and documented the duration and type of their activities (based on the PRISCUS-Physical Activity Questionnaire) during the respective time intervals. They were furthermore assessed regarding motor and nonmotor symptoms, personality factors, and coping strategies.

RESULTS

Patients spent on average 8.59 ± 2.93 hr per day at physical rest and 5.47 ± 2.93 hr physically active. We found highly significant associations between positive condition ratings (such as happiness, motivation, and concentration) and the duration of subsequent physical activities (adj.r²  = .689) as well as between the duration of these activities and a subsequent improvement in the subjective condition (adj.r²  = .545). This was strongest in patients using active coping strategies and showing agreeable and conscientious personality traits (adj.r²  = .380). Nonmotor symptom severity was weakly inversely related to the daily amount of activities (adj.r²  = .273), whereas no significant association with motor symptom severity was found.

CONCLUSIONS

The results suggest a feedback process between a positive subjective condition and physical activities in PD patients. This appears to depend on the use of active coping strategies and nonmotor symptoms rather than on motor symptom severity. The results should encourage physicians to address the importance of everyday physical activities and to provide patients with behavioral advice.

Apathy in Patients with Parkinson's Disease Correlates with Alteration of Left Fronto-Polar Electroencephalographic Connectivity

Introduction: Quantitative electroencephalography (QEEG) brain frequency and network analyses are known to differentiate between disease stages in Parkinson's disease (PD) and are possible biomarkers. They correlate with cognitive decline. Little is known about changes in brain networks in relation to apathy.

Objective/Aims: To analyze changes in brain network connectivities related to apathy.

Methods: 40 PD patients (14 PD with mild cognitive deficits and 26 PD with normal cognition) were included. All patients had extensive neuropsychological testing; apathy was evaluated using the apathy evaluation score (AES, median 24.5, range 18–39). Resting state EEG was recorded with 256 electrodes and analyzed using fully automated Matlab® code (TAPEEG). For estimation of the connectivities between brain regions, PLI (phase lag index) was used, enhanced by a microstates segmentation.

Results: After correction for multiple comparisons, significant correlations were found for single alpha2-band connectivities with the AES (p-values < 0.05). Lower connectivities, mainly involving the left fronto-polar region, were related to higher apathy scores.

Conclusions: In our sample of patients with PD, apathy correlates with a network alteration mainly involving the left fronto-polar region. This might be due to dysfunction of the cortico-basal loop, modulating motivation.

Atypical antipsychotic therapy in Parkinson's disease psychosis: A retrospective study

OBJECTIVE

Parkinson's disease psychosis (PDP) is a frequent complication of idiopathic Parkinson's disease (iPD) with significant impact on quality of life and association with poorer outcomes. Atypical antipsychotic drugs (APDs) are often used for the treatment of PDP; however, their use is often complicated by adverse drug reactions (ADRs). In this study, we present patients with PDP who were treated with the most commonly used atypical antipsychotic agents and review their respective ADRs.

METHODS

A retrospective study was carried out to include a total of 45 patients with iPD who visited a movement disorders clinic between 2006 and 2015. All PDP patients treated with atypical APDs were included in the analysis for their specific ADRs.

RESULTS

Forty-five iPD patients (mean age of onset: 62.67 ± 9.86 years) were included, of those 10 patients had psychosis (mean age of onset: 76.80 ± 4.61 years). Of the 45 patients, 22.2% were found to have psychotic symptoms, of whom 70% had hallucinations, 20% had delusions, and 10% illusions. Seventy percent of psychotic symptoms occurred after ten or more years from diagnosis of iPD. PDP patients were treated with quetiapine, olanzapine, and risperidone separately or in combination, all of which were found to have certain ADRs.

LIMITATIONS

This study was limited by its retrospective study design and small sample size and with likely selection bias.

CONCLUSIONS

The prevalence of PDP is relatively high in older patients with iPD. The uses of the currently available atypical APDs in this patient population are often complicated by ADRs. The selective 5-HT _2A inverse agonist, pimavanserin, could be a better alternative in the treatment of PDP.

Does apolipoprotein A1 predict microstructural changes in subgenual cingulum in early Parkinson?

Higher plasma cholesterol levels are associated with lower Parkinson's disease (PD) risk. Apolipoprotein A-1 (ApoA-1) is a surface marker of brain HDL-like particles associated with the time of PD onset. Clinical correlates of serum Apolipoprotein A1 levels with structural brain connectivity in PD-related disorders remains unclear. Here, we applied a novel diffusion-weighted imaging approach [Diffusion Magnetic Resonance Imaging (MRI) Connectometry] to explore the association between ApoA-1 and structural brain connectivity in PD. Participants involved in this research were recruited from Parkinson's Progression Markers Initiative (PPMI). Diffusion MRI connectometry was conducted using a multiple regression against apoA-1 for 36 patients with DTI measurements available in the baseline visit. Fiber results of the connectometry were then reconstructed for each patient, and diffusion parameters were extracted and regressed against apoA-1 levels. Connectometry results revealed the subgenual cingulum to be associated with ApoA-1, with different FDR yields. This result was further supported by significant negative correlation of Quantitative Anisotropic (QA) of left subgenual cingulum (Pearson's coefficient = -0.398, p = 0.020) and Generalized Fractional Anisotropic (GFA) of right subgenual cingulum (Pearson's coefficient -0.457, p = 0.007) with plasma apoA-1 levels, in a multiple regression model with age and sex. The subgenual cingulum encompasses fibers from the anterior cingulate cortex and anterior thalamus. These structures are involved in PD-associated psychosis and executive cognitive decline. We demonstrated for the first time that apoA-1, as a blood marker, can predict microstructural changes in white matter regions in PD patients with undisturbed cognition and mild motor disability.

Depressive symptoms in Parkinson's disease correlate with cortical atrophy over time

INTRODUCTION

Depressive symptoms are very common in patients with Parkinson's disease (PD) and have a significant impact on the quality of life.

METHODS

The present study analyzed the correlations between over-time changes in depressive symptoms and gray matter parameters of cortical thickness and subcortical volumes in non-demented PD patients.

RESULTS

A significant correlation was observed, between increased scores for depression over time and lower cortical thickness over time in the right temporo-parietal junction, right occipital medial region, right dorsolateral prefrontal cortex, right posterior cingulate region, left middle temporal as well as left supplementary motor area. Furthermore, the presence of depressive symptoms at baseline predicted increased cortical thinning over time in the left middle temporal, left anterior cingulate, right posterior cingulate and right parahippocampal cortices. Finally, a statistically significant negative correlation has been revealed between the thalamus' volume changes over time and the change in depressive symptoms scores. All other analyzed subcortical structures didn't reveal any significant correlations.

CONCLUSION

These results suggest that depressive symptoms in PD patients are associated with gray matter cortical thinning and thalamus volume shrinkage over time and higher scores of depressive symptoms at baseline correlate with a higher rate of cortical thinning longitudinally. The present study highlights the importance of addressing depressive symptoms in PD patients early in the disease.

Psychiatric Conditions in Parkinson Disease: A Comparison With Classical Psychiatric Disorders

Psychiatric conditions often complicate the outcome of patients affected by Parkinson disease (PD), but they differ from classical psychiatric disorders in terms of underlying biological mechanisms, clinical presentation, and treatment response. The purpose of the present review is to illustrate the biological and clinical aspects of psychiatric conditions associated with PD, with particular reference to the differences with respect to classical psychiatric disorders. A careful search of articles on main databases was performed in order to obtain a comprehensive review about the main psychiatric conditions associated with PD. A manual selection of the articles was then performed in order to consider only those articles that concerned with the topic of the review. Psychiatric conditions in patients with PD present substantial differences with respect to classical psychiatric disorders. Their clinical presentation does not align with the symptom profiles represented by Diagnostic and Statistical Manual for Mental Disorders and International Classification of Diseases. Furthermore, psychiatry treatment guidelines are of poor help in managing psychiatric symptoms of patients with PD. Specific diagnostic tools and treatment guidelines are needed to allow early diagnosis and adequate treatment of psychiatric conditions in comorbidity with PD.

Impact of Current Antipsychotic Medications on Comparative Mortality and Adverse Events in People With Parkinson Disease Psychosis

OBJECTIVES

To establish the mortality risk and adverse events associated with the use of atypical antipsychotic medications in people with Parkinson disease psychosis (PDP) in a clinically defined trial cohort.

DESIGN

Post hoc analysis of data from a multicenter, open-label extension study of pimavanserin comparing people taking and not taking current antipsychotics.

SETTING

Primary and secondary care medical centers in the United States, Canada, Europe, and India.

PARTICIPANTS

A total of 459 people with PDP enrolled in the extension study. Participants were between ages 30 and 80 years, and had an established diagnosis of idiopathic Parkinson disease and moderate to severe psychosis.

INTERVENTIONS

Participants were categorized into 2 groups: those receiving concomitant antipsychotic medications ("concurrent APD") and those who did not take antipsychotic medications at any time during the study ("no APD"). Participants were receiving 40 mg pimavanserin daily in addition to concurrent antipsychotics and Parkinson disease medications.

MAIN OUTCOME MEASURES

Safety assessments at 2 weeks; 1, 3, 6, 9, and 12 months; and every 6 months thereafter, including evaluation of adverse events (AEs), vital signs, weight, physical examinations, 12-lead electrocardiograms, clinical laboratory tests (serum chemistry, hematology, and urinalysis), and the Unified Parkinson's Disease Rating Scale Parts II and III (UPDRS-II+III, activities of daily living and motor impairment, respectively). Differences between participants taking and not taking current antipsychotics were evaluated using incidence rate ratios (IRRs) with 95% confidence intervals (CIs).

RESULTS

There was significant increase in the mortality rate for participants taking concurrent antipsychotics compared with the group not taking antipsychotic medications (IRR 4.20, 95% CI 2.13-7.96). Participants who received a concurrent antipsychotic were also significantly more likely to experience overall a serious AE (IRR 2.95, 95% CI 2.02-4.24), any antipsychotic-related event (IRR 1.66, 95% CI 1.18-2.29), cognition-related events (IRR 2.70, 95% CI 1.19-5.58), infections (IRR 1.97, 95% CI 1.17-3.16), and edema (IRR 2.61, 95% CI 1.09-5.59). The risk of falls, stroke, sedation, orthostatic hypotension, and thromboembolic events was also increased in these individuals but this was not significant.

CONCLUSIONS

This study highlights a significant risk of mortality, and severe AEs in patients with Parkinson disease receiving atypical antipsychotics. This is similar to or greater than the risks seen in people with Alzheimer disease, although with a less clear-cut risk of stroke and a longer delay to increased mortality.

Non-motor signs in Parkinson's disease: a review

During the past decade the view of Parkinson's disease (PD) as a motor disorder has changed significantly and currently it is recognized as a multisystem process with diverse non-motor signs (NMS). In addition to been extremely common, these NMS play a major role in undermining functionality and quality of life. On the other hand, NMS are under recognized by physicians and neglected by patients. Here, we review the most common NMS in PD, including cognitive, psychiatric, sleep, metabolic, and sensory disturbances, discuss the current knowledge from biological, epidemiological, clinical, and prognostic standpoints, highlighting the need for early recognition and management.

Apathy in Parkinson's disease is related to executive function, gender and age but not to depression

Deficits in executive functions occur in up to 93% of patients with Parkinson's disease (PD). Apathy, a reduction of motivation and goal-directed behavior is an important part of the syndrome; affecting both the patients as well as their social environment. Executive functions can be subdivided into three different processes: initiation, shifting and inhibition. We examined the hypotheses, (1) that apathy in patients with Parkinson's disease is only related to initiation and not to shifting and inhibition, and (2) that depression and severity of motor signs correlate with apathy. Fifty-one non-demented patients (19 = female) with PD were evaluated for apathy, depression and executive functions. Executive function variables were summarized with an index variable according to the defined executive processes. Linear regression with stepwise elimination procedure was used to select significant predictors. The significant model (R² = 0.41; p < 0.01) revealed influences of initiation (b = −0.79; p < 0.01), gender (b = −7.75; p < 0.01), age (b = −0.07; p < 0.05) and an age by gender interaction (b = 0.12; p < 0.01) on apathy in Parkinson's disease. Motor signs, depression and level of education did not influence the relation. These results support an association of apathy and deficits of executive function in PD. Initiation strongly correlates with apathy, whereas depression does not. We conclude, that initiation dysfunction in a patient with Parkinson's disease heralds apathy. Apathy and depression can be dissociated. Additionally, apathy is influenced by age and gender: older age correlates with apathy in men, whereas in women it seems to protect against it.

Influence of depressive symptoms on dopaminergic treatment of Parkinson's disease

Introduction: Depressive symptoms are very common in patients with Parkinson’s disease (PD) and have a significant impact on the quality of life. Dopaminergic medication has been shown to have an influence on the development of depressive symptoms.

Materials and methods: The present study analyzed two groups of non-demented patients with PD, with and without depressive symptoms, and reported the correlations between antiparkinsonian medication [specifically levodopa (l-DOPA) and dopaminergic agonists] with depressive symptoms.

Results: A strong statistically significant positive correlation between l-DOPA dosages and the level of depressive symptoms has been revealed, suggesting that higher l-DOPA dosages correlate with a worsening of depressive status. No significant correlation was found with dopamine agonists.

Discussion: The results of this study show that in patients with PD, higher l-DOPA dosages correlate with worse depressive symptoms. From this point of view, PD patients need to be better diagnosed with respect to depressive symptoms and need additional treatment adjustment when clinical manifestations of depression are present. Clinicians must be aware that dopaminergic drugs are not sufficient to alleviate depressive symptoms.

Why psychosis is frequently associated with Parkinson's disease?

Psychosis is a common non-motor symptom of Parkinson's disease whose pathogenesis remains poorly understood. Parkinson's disease in conjunction with psychosis has been shown to induce injury to extracorticospinal tracts as well as within some cortical areas. In this study, Parkinson's disease patients with psychosis who did not receive antipsychotic treatment and those without psychosis underwent diffusion tensor imaging. Results revealed that in Parkinson's disease patients with psychosis, damage to the left frontal lobe, bilateral occipital lobe, left cingulated gyrus, and left hippocampal white-matter fibers were greater than damage to the substantia nigra or the globus pallidus. Damage to white-matter fibers in the right frontal lobe and right cingulate gyrus were also more severe than in the globus pallidus, but not the substantia nigra. Damage to frontal lobe and cingulate gyrus white-matter fibers was more apparent than that to occipital or hippocampal fiber damage. Compared with Parkinson's disease patients without psychosis, those with psychosis had significantly lower fractional anisotropy ratios of left frontal lobe, bilateral occipital lobe, left cingu-lated gyrus, and left hippocampus to ipsilateral substantia nigra or globus pallidus, indicating more severe damage to white-matter fibers. These results suggest that psychosis associated with Par-kinson's disease is probably associated with an imbalance in the ratio of white-matter fibers be-tween brain regions associated with psychiatric symptoms (frontal lobe, occipital lobe, cingulate gyrus, and hippocampus) and those associated with the motor symptoms of Parkinson's disease (the substantia nigra and globus pallidus). The relatively greater damage to white-matter fibers in psychiatric symptom-related brain regions than in extracorticospinal tracts might explain why chosis often occurs in Parkinson's disease patients.

Protective effects of curcumin against rotenone and salsolinol-induced toxicity: implications for Parkinson's disease

Parkinson's disease (PD) is a debilitating neurodegenerative disorder that results from the loss of or damage to dopaminergic cells in the substantia nigra. Exposure to either the pesticide rotenone or the endogenous neurotoxin salsolinol has been shown to mimic this dopaminergic cell loss. In this study, we first sought to determine whether combination of rotenone and salsolinol would result in an additive or synergistic toxicity. For this purpose we utilized SH-SY5Y cells, a human neuroblastoma cell line that is commonly used to model dopaminergic neurodegeneration. We then tested whether curcumin, a natural plant compound with known health benefits including potential neuroprotective properties, could also protect against rotenone and/or salsolinol-induced toxicity. Moreover, since apoptotic mechanism has been implicated in toxicity of these compounds the anti-apoptotic effect of curcumin was also evaluated. Our results indicate a synergistic toxicity of low concentrations of rotenone (1 and 5 µM) and salsolinol (25 and 50 µM) that was associated with apoptosis as determined by cell flow cytometry. There was also an increase in caspase-3 levels. Pretreatment with curcumin (1-µM) dose-dependently attenuated rotenone and/or salsolinol-induced toxicity and the associated apoptosis. These results suggest that exposure to a combination of rotenone and salsolinol may contribute to the pathology of PD, and that curcumin has a therapeutic potential in this disease.

Clinical neurogenetics: behavioral management of inherited neurodegenerative disease

Psychiatric symptoms often manifest years before overt neurologic signs in patients with inherited neurodegenerative disease. The most frequently cited example of this phenomenon is the early onset of personality changes in "presymptomatic" Huntington patients. In some cases the changes in mood and cognition are even more debilitating than their neurologic symptoms. The goal of this article is to provide the neurologist with a concise primer that can be applied in a busy clinic or private practice.

Subjective memory complaints, depressive symptoms and cognition in Parkinson's disease patients

BACKGROUND AND PURPOSE

The goal of this study was to establish the prevalence of subjective memory complaints (SMCs) and depressive symptoms (DS)s and their relation to cognitive functioning in patients with Parkinson's disease (PD).

METHODS

In all, 248 controls and 104 PD patients were included in the study. The PD group was subdivided into three PD subtypes with mild cognitive impairment (MCI) according to the Petersen criteria and three PD subtypes with MCI according to the Litvan criteria.

RESULTS

Substantial SMCs were reported by 7.7% of controls and 16.3% of the PD patients (P < 0.001). A clinically relevant degree of DSs was evident in 16.6% of controls compared with 40.4% in the PD group (P < 0.001). An analysis of variance revealed a statistically significant difference for SMCs across all Petersen groups as well across all Litvan groups. Two-factor analyses of variance with the factors cognitive status (MCI subtype) and depressive state (depressed versus not depressed) and SMCs as dependent variable revealed significant results.

CONCLUSIONS

Approximately 15% of PD patients seeking help in a movement disorder clinic report significant SMCs, with an increasing degree from cognitively healthy PD to PD-MCI. Significant DSs increase SMCs across all cognitive status groups.

[Coexistent depressive and anxiety disorders in neurological diseases: from a perspective of multimorbidity]

The high rate of coexistent emotional disorders in neurological diseases is challenging. As a rule this coexistence comprises a more dramatic subjective suffering, reduced psychological coping, possible negative interferences with somatic treatments and rehabilitation, an impaired quality of life and higher grades of psychosocial disability. It may also lead to an overall increased risk of somatic morbidity and even mortality in the further course of illness. The complex interrelations may be favorably integrated within a biopsychosocial model. Psychological and psychosocial stressors can be appreciated on their own discrete levels but have to be reflected in their neurobiological correlates. Both neurological and emotional disorders frequently share decisive pathogenetic mechanisms, i.e. the underlying process of neurological disease may contribute to major affective problems also in a somatopsychic direction. From a perspective of multimorbidity the prevalence and clinical relevance of coexistent depressive and anxiety disorders, common pathogenetic mechanisms and implications for treatment will be described for stroke and Parkinson's disease, as selected neurological disorders.

Pimavanserin for patients with Parkinson's disease psychosis: a randomised, placebo-controlled phase 3 trial

BACKGROUND

Parkinson's disease psychosis, which includes hallucinations and delusions, is frequent and debilitating in people with Parkinson's disease. We aimed to assess safety and efficacy of pimavanserin, a selective serotonin 5-HT2A inverse agonist, in this population.

METHODS

In our 6 week, randomised, double-blind, placebo-controlled study, we enrolled adults (aged ≥40 years) with Parkinson's disease psychosis. Antipsychotic treatments were not permitted during the study, but controlled antiparkinsonian medication or deep brain stimulation was allowed. Eligible participants entered a 2 week non-pharmacological lead-in phase to limit the placebo response, after which they were randomly allocated (1:1) to receive pimavanserin 40 mg per day or matched placebo. The primary outcome was antipsychotic benefit as assessed by central, independent raters with the Parkinson's disease-adapted scale for assessment of positive symptoms (SAPS-PD) in all patients who received at least one dose of study drug and had a SAPS assessment at baseline and at least one follow-up. We assessed safety and tolerability in all patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, number NCT01174004.

FINDINGS

Between Aug 11, 2010, and Aug 29, 2012, we randomly allocated 199 patients to treatment groups. For 90 recipients of placebo and 95 recipients of pimavanserin included in the primary analysis, pimavanserin was associated with a -5·79 decrease in SAPS-PD scores compared with -2·73 for placebo (difference -3·06, 95% CI -4·91 to -1·20; p=0·001; Cohen's d 0·50). Ten patients in the pimavanserin group discontinued because of an adverse event (four due to psychotic disorder or hallucination within 10 days of start of the study drug) compared with two in the placebo group. Overall, pimavanserin was well tolerated with no significant safety concerns or worsening of motor function.

INTERPRETATION

Pimavanserin may benefit patients with Parkinson's disease psychosis for whom few other treatment options exist. The trial design used in this study to manage placebo response could have applicability to other studies in neuropsychiatric disease.

FUNDING

ACADIA Pharmaceuticals.

Lorcaserin and pimavanserin: emerging selectivity of serotonin receptor subtype-targeted drugs

Serotonin (5-hydroxytryptamine, or 5-HT) receptors mediate a plethora of physiological phenomena in the brain and the periphery. Additionally, serotonergic dysfunction has been implicated in nearly every neuropsychiatric disorder. The effects of serotonin are mediated by fourteen GPCRs. Both the therapeutic actions and side effects of commonly prescribed drugs are frequently due to nonspecific actions on various 5-HT receptor subtypes. For more than 20 years, the search for clinically efficacious drugs that selectively target 5-HT receptor subtypes has been only occasionally successful. This review provides an overview of 5-HT receptor pharmacology and discusses two recent 5-HT receptor subtype-selective drugs, lorcaserin and pimavanserin, which target the 5HT2C and 5HT2A receptors and provide new treatments for obesity and Parkinson's disease psychosis, respectively.

Patients' expectations of deep brain stimulation, and subjective perceived outcome related to clinical measures in Parkinson's disease: a mixed-method approach

OBJECTIVE

To study patients' expectations of subthalamic deep brain stimulation (STN-DBS) and their subjective perceived outcome, by using qualitative and quantitative methods in Parkinson's disease (PD).

METHODS

PD patients were prospectively examined before and 3 months after surgery. Semistructured interviews regarding preoperative expectations and postsurgical subjective perceived outcome were conducted. These were analysed using content analysis. For statistical analyses, patients were classified according to their subjective perceived outcome, resulting in three different subjective outcome groups (negative, mixed, positive outcome). The groups were used for multiple comparisons between and within each group regarding motor impairment, quality of life (QoL), neuropsychiatric status and cognitive functioning, using standard instruments. A logistic regression analysis was conducted to find predictors of subjective negative outcome. Receiver operating characteristic curves were used to analyse cut-off scores for predictive tests.

RESULTS

Of the 30 PD patients participating, 8 had a subjective negative outcome, 8 a mixed and 14 a positive outcome. All groups significantly improved in motor functioning. Patients with subjective negative outcome were characterised by preoperative unrealistic expectations, no postsurgical improvement in QoL, and significantly higher presurgical and postsurgical apathy and depression scores. Higher preoperative apathy and depression scores were significant predictors of negative subjective outcome. Cut-off scores for apathy and depression were identified.

CONCLUSIONS

The mixed-method approach proved useful in examining a patient's subjective perception of STN-DBS outcome. Our results show that significant motor improvement does not necessarily lead to a positive subjective outcome. Moreover, PD patients should be screened carefully before surgery regarding apathy and depression. (DRKS-ID: DRKS00003221).

The neuropsychiatry of hyperkinetic movement disorders: insights from neuroimaging into the neural circuit bases of dysfunction

BACKGROUND

Movement disorders, particularly those associated with basal ganglia disease, have a high rate of comorbid neuropsychiatric illness.

METHODS

We consider the pathophysiological basis of the comorbidity between movement disorders and neuropsychiatric illness by 1) reviewing the epidemiology of neuropsychiatric illness in a range of hyperkinetic movement disorders, and 2) correlating findings to evidence from studies that have utilized modern neuroimaging techniques to investigate these disorders. In addition to diseases classically associated with basal ganglia pathology, such as Huntington disease, Wilson disease, the neuroacanthocytoses, and diseases of brain iron accumulation, we include diseases associated with pathology of subcortical white matter tracts, brain stem nuclei, and the cerebellum, such as metachromatic leukodystrophy, dentatorubropallidoluysian atrophy, and the spinocerebellar ataxias.

CONCLUSIONS

Neuropsychiatric symptoms are integral to a thorough phenomenological account of hyperkinetic movement disorders. Drawing on modern theories of cortico-subcortical circuits, we argue that these disorders can be conceptualized as disorders of complex subcortical networks with distinct functional architectures. Damage to any component of these complex information-processing networks can have variable and often profound consequences for the function of more remote neural structures, creating a diverse but nonetheless rational pattern of clinical symptomatology.