Psychotic symptoms in Parkinson's disease patients with dementia

Integrating Clinical Neuropsychology and Psychotic Spectrum Disorders: A Systematic Analysis of Cognitive Dynamics, Interventions, and Underlying Mechanisms

Background and Objectives: The study aims to provide a comprehensive neuropsychological analysis of psychotic spectrum disorders, including schizophrenia, bipolar disorder, and depression. It focuses on the critical aspects of cognitive impairments, diagnostic tools, intervention efficacy, and the roles of genetic and environmental factors in these disorders. The paper emphasizes the diagnostic significance of neuropsychological tests in identifying cognitive deficiencies and their predictive value in the early management of psychosis. Materials and Methods: The study involved a systematic literature review following the PRISMA guidelines. The search was conducted in significant databases like Scopus, PsycINFO, PubMed, and Web of Science using keywords relevant to clinical neuropsychology and psychotic spectrum disorders. The inclusion criteria required articles to be in English, published between 2018 and 2023, and pertinent to clinical neuropsychology's application in these disorders. A total of 153 articles were identified, with 44 ultimately included for detailed analysis based on relevance and publication status after screening. Results: The review highlights several key findings, including the diagnostic and prognostic significance of mismatch negativity, neuroprogressive trajectories, cortical thinning in familial high-risk individuals, and distinct illness trajectories within psychosis subgroups. The studies evaluated underline the role of neuropsychological tests in diagnosing psychiatric disorders and emphasize early detection and the effectiveness of intervention strategies based on cognitive and neurobiological markers. Conclusions: The systematic review underscores the importance of investigating the neuropsychological components of psychotic spectrum disorders. It identifies significant cognitive impairments in attention, memory, and executive function, correlating with structural and functional brain abnormalities. The paper stresses the need for precise diagnoses and personalized treatment modalities, highlighting the complex interplay between genetic, environmental, and psychosocial factors. It calls for a deeper understanding of these neuropsychological processes to enhance diagnostic accuracy and therapeutic outcomes.

Psychotic Symptoms in Patients With Major Neurological Diseases

Neurological diseases often manifest with neuropsychiatric symptoms such as depression, emotional incontinence, anger, apathy and fatigue. In addition, affected patients may also experience psychotic symptoms such as hallucinations and delusions. Various factors contribute to the development of psychotic symptoms, and the mechanisms of psychosis are similar, but still differ among various neurological diseases. Although psychotic symptoms are uncommon, and have been less well investigated, they may annoy patients and their families as well as impair the patients' quality of life and increase the caregiver burden. Therefore, we need to appropriately identify and treat these psychotic symptoms in patients with neurological diseases.

Parkinson's disease and schizophrenia interactomes contain temporally distinct gene clusters underlying comorbid mechanisms and unique disease processes

Genome-wide association studies suggest significant overlaps in Parkinson's disease (PD) and schizophrenia (SZ) risks, but the underlying mechanisms remain elusive. The protein-protein interaction network ('interactome') plays a crucial role in PD and SZ and can incorporate their spatiotemporal specificities. Therefore, to study the linked biology of PD and SZ, we compiled PD- and SZ-associated genes from the DisGeNET database, and constructed their interactomes using BioGRID and HPRD. We examined the interactomes using clustering and enrichment analyses, in conjunction with the transcriptomic data of 26 brain regions spanning foetal stages to adulthood available in the BrainSpan Atlas. PD and SZ interactomes formed four gene clusters with distinct temporal identities (Disease Gene Networks or 'DGNs'1-4). DGN1 had unique SZ interactome genes highly expressed across developmental stages, corresponding to a neurodevelopmental SZ subtype. DGN2, containing unique SZ interactome genes expressed from early infancy to adulthood, correlated with an inflammation-driven SZ subtype and adult SZ risk. DGN3 contained unique PD interactome genes expressed in late infancy, early and late childhood, and adulthood, and involved in mitochondrial pathways. DGN4, containing prenatally-expressed genes common to both the interactomes, involved in stem cell pluripotency and overlapping with the interactome of 22q11 deletion syndrome (comorbid psychosis and Parkinsonism), potentially regulates neurodevelopmental mechanisms in PD-SZ comorbidity. Our findings suggest that disrupted neurodevelopment (regulated by DGN4) could expose risk windows in PD and SZ, later elevating disease risk through inflammation (DGN2). Alternatively, variant clustering in DGNs may produce disease subtypes, e.g., PD-SZ comorbidity with DGN4, and early/late-onset SZ with DGN1/DGN2.

Dementia-related psychosis and the potential role for pimavanserin

Dementia-related psychosis (DRP) is prevalent across dementias and typically manifests as delusions and/or hallucinations. The mechanisms underlying psychosis in dementia are unknown; however, neurobiological and pharmacological evidence has implicated multiple signaling pathways and brain regions. Despite differences in dementia pathology, the neurobiology underlying psychosis appears to involve dysregulation of a cortical and limbic pathway involving serotonergic, gamma-aminobutyric acid ergic, glutamatergic, and dopaminergic signaling. Thus, an imbalance in cortical and mesolimbic excitatory tone may drive symptoms of psychosis. Delusions and hallucinations may result from (1) hyperactivation of pyramidal neurons within the visual cortex, causing visual hallucinations and (2) hyperactivation of the mesolimbic pathway, causing both delusions and hallucinations. Modulation of the 5-HT2A receptor may mitigate hyperactivity at both psychosis-associated pathways. Pimavanserin, an atypical antipsychotic, is a selective serotonin inverse agonist/antagonist at 5-HT2A receptors. Pimavanserin may prove beneficial in treating the hallucinations and delusions of DRP without worsening cognitive or motor function.

Frequency and Characteristics of Psychosis in Parkinson's Disease: A Systematic Review and Meta-Analysis

BACKGROUND

Psychotic symptoms are highly frequent in Parkinson's disease (PD) patients and are associated with poor prognosis. They include hallucinations, delusions, and minor psychotic phenomena, including sense of presence, passage hallucinations, and illusions.

OBJECTIVE

To evaluate the frequency of psychosis in PD patients.

METHODS

A systematic review and meta-analysis of clinical trials, prospective and retrospective cohort studies, case-control studies, and cross-sectional studies reporting the frequency of psychosis, hallucinations, and delusions in PD.

RESULTS

Electronic database search wielded 3536 articles, an additional 91 were identified through citation chaining. Of these, 163 were fully inspected, 57 removed, and 106 included as relevant for neuropsychiatric events frequency, with 32 meeting our inclusion criteria (psychosis and/or specific psychotic phenomena). The pooled frequency of psychosis was 20.7% (95% CI 14.5 to 28.6; I2 = 94%, 15 studies; combined n = 2919). None of the pre-defined meta-regressions or subgroup analyses were statistically significant or helped explain the statistical heterogeneity. The pooled frequency of any form of hallucination was 21.6% (95% CI 14.7 to 30.6; I2 = 95%; 18 studies; combined n = 3161). Duration of PD at baseline and mean baseline Hoehn & Yahr stage helped explain the statistical heterogeneity in the meta-analysis of hallucinations.

CONCLUSION

Based on the available evidence, around a fifth of PD patients experience psychosis or hallucinations. The risk of developing hallucinations is likely moderated by the disease duration, Hoehn & Yahr stage, and the cognitive status.

Delusion and Delirium in Neurodegenerative Disorders: An Overlooked Relationship?

Delusions are part of the neuropsychiatric symptoms that patients suffering from neurodegenerative conditions frequently develop at some point of the disease course and are associated with an increased risk of cognitive and functional decline. Delirium is a syndrome characterized by acute onset of deficits in attention, awareness, and cognition that fluctuate in severity over a short time period. Delusions and delirium are frequently observed in the context of neurodegeneration, and their presence can easily mislead clinicians toward a misdiagnosis of psychiatric disorder further delaying the proper treatment. Risk factors for developing delusion and delirium in neurodegenerative conditions have been investigated separately while the possible interplay between these two conditions has not been explored so far. With this study, we aim to achieve a more comprehensive picture of the relationship between delusions and delirium in neurodegeneration by analyzing prevalence and subtypes of delusions in different neurodegenerative disorders; providing an overview of clinical tools to assess delusions in neurodegenerative patients and how delusions are covered by delirium assessment tools and discussing the possible common pathophysiology mechanisms between delusion and delirium in neurodegenerative patients. A more extensive characterization of the relationship between delusions and delirium may help to understand whether delusions may constitute a risk factor for delirium and may ameliorate the management of both conditions in patients with neurodegenerative disorders.

Visual Hallucinations and Impaired Conscious Visual Perception in Parkinson Disease

Visual hallucinations (VHs) are common in patients with Parkinson disease (PD), especially those with dementia, whereas auditory hallucinations are quite rare. Recent studies have revealed the involvement of several regions along the visual information-processing system that contribute to the pathophysiological mechanism of VHs: the eyes and retina, retinofugal projection, lateral geniculate nucleus, striate cortex, ventral pathways in the temporal cortices, and frontal and parietal cortices. In addition, the concurrent involvement of other systems in the brainstem and basal forebrain further modify VHs in PD. In this review, we discuss the pathophysiological association between the regional involvement of these areas and VHs.

Lewy Body Degenerations as Neuropsychiatric Disorders

Parkinson disease has historically been conceptualized as a movement disorder. In recent decades, nonmotor and neuropsychiatric symptoms have become increasingly recognized as being of paramount importance for patients with Parkinson disease. Neuropsychiatric phenomena dominate the course of the other major Lewy body disease, dementia with Lewy bodies. In this review, we survey the clinical relevance of nonmotor and neuropsychiatric symptoms to the heterogeneous presentations of Lewy body disease and their significance to ongoing research in this area. We consider how the nature of Lewy body neuropathology may help explicate the basis of nonmotor and neuropsychiatric symptoms in these two disorders.

Terminology and assessment tools of psychosis: A systematic narrative review

AIM

Phenomena within the psychosis continuum that varies in frequency/duration/intensity have been increasingly identified. Different terms describe these phenomena, however there is no standardization within the terminology. This review evaluated the definitions and assessment tools of seven terms - (i) 'psychotic experiences'; (ii) 'psychotic-like experiences'; (iii) 'psychotic-like symptoms'; (iv) 'attenuated psychotic symptoms'; (v) 'prodromal psychotic symptoms'; (vi) 'psychotic symptomatology'; and (vii) 'psychotic symptoms'.

METHODS

EMBASE, MEDLINE, and CINAHL were searched during February-March 2019. Inclusion criteria included 1989-2019, full text, human, and English. Papers with no explicit definition or assessment tool, duplicates, conference abstracts, systematic reviews, meta-analyses, or no access were excluded.

RESULTS

A total of 2238 papers were identified and of these, 627 were included. Definitions and assessment tools varied, but some trends were found. Psychotic experiences and psychotic-like experiences were transient and mild, found in the general population and those at-risk. Psychotic-like symptoms were subthreshold and among at-risk populations and non-psychotic mental disorders. Attenuated psychotic symptoms were subthreshold but associated with distress, risk, and help-seeking. Prodromal psychotic symptoms referred to the prodrome of psychotic disorders. Psychotic symptomatology included delusions and hallucinations within psychotic disorders. Psychotic symptoms was the broadest term, encompassing a range of populations but most commonly involving hallucinations, delusions, thought disorder, and disorganization.

DISCUSSION

A model for conceptualizing the required terms is proposed and future directions needed to advance this field of research are discussed.

Neuroepigenetics of Aging and Age-Related Neurodegenerative Disorders

Neurodegenerative diseases are complex, progressive disorders and affect millions of people worldwide, contributing significantly to the global burden of disease. In recent years, research has begun to investigate epigenetic mechanisms for a potential role in disease etiology. In this chapter, we describe the current state of play for epigenetic research into neurodegenerative disorders including Alzheimer's disease, Parkinson's disease and Huntington's disease. We focus on the recent evidence for a potential role of DNA modifications, histone modifications and non-coding RNA in the etiology of these disorders. Finally, we discuss how new technological and bioinformatics advances in the field of epigenetics could further progress our understanding about the underlying mechanisms of neurodegenerative diseases.

Treating Hallucinations and Delusions Associated With Parkinson's Disease Psychosis

PURPOSE OF REVIEW

We discuss features of Parkinson's disease psychosis (PDP) including symptomology and pathophysiology. Treatment options, including non-pharmacologic strategies, dose reduction of offending agents, and the addition of non-dopaminergic antipsychotics, are addressed. The efficacy of second-generation antipsychotics and novel agents is examined.

RECENT FINDINGS

Pimavanserin, a 5-HT_2A/C receptor inverse agonist with no other receptor activity, has shown efficacy and tolerability and is now FDA approved for PDP treatment. Research into novel targets is ongoing. PDP is a morbid complication of Parkinson's disease with complex incompletely understood mechanisms. Treatment is directed towards mitigation of psychosis without worsening of motor features.

Parkinson's disease psychosis: presentation, diagnosis and management

Parkinson's disease is a neurodegenerative disorder characterized by motor and nonmotor symptoms. Psychosis is a common feature of Parkinson's disease. Parkinson's disease psychosis (PDP) encompasses minor phenomena (illusions, passage hallucinations and presence hallucinations), visual and nonvisual hallucinations and delusions. PDP is associated with reduced function and quality of life. The initial management approach should focus on identification and treatment of any contributory medical factors, reduction or discontinuation of medications with potential to induce or worsen psychosis, nonpharmacological strategies and consideration of acetylcholinesterase inhibitor treatment in the setting of dementia. Pimavanserin, quetiapine and clozapine may all be considered for use in PDP. In this review, we discuss the presentation, diagnosis and management of PDP.

Successful Use of Escitalopram for the Treatment of Visual Hallucinations in Patients With Parkinson Disease

INTRODUCTION

Patients with Parkinson disease (PD) frequently experience visual hallucinations (VH). Visual hallucinations are most often viewed as an adverse effect of antiparkinsonian treatment. Possible treatments for this disturbance include a reduction of antiparkinsonian medications, adding atypical antipsychotics, or cholinesterase inhibitors. Some studies demonstrated that selective serotonin reuptake inhibitors may be an optional treatment for patients experiencing psychosis or agitation in dementia. Currently, there is no standard recommended treatment for VH in patients with PD. We present here our clinical experience with escitalopram (selective serotonin reuptake inhibitor) for treating this disturbance.

METHODS

Thirteen patients with PD (8 men and 5 women; age range 67-83 years) experiencing VH were openly treated with escitalopram 10 or 15 mg/d as add-on. Efficacy was assessed at baseline, then after 4 and 8 weeks of treatment using Clinical Global Impression-Severity and Clinical Global Impression-Improvement.

RESULTS

At the end of the 4th week of treatment, of 13 patients, 11 subjects demonstrated improvement, and in only 2 patients were there no changes in their condition. After an additional 4 weeks, 2 of the responders showed very significant improvement, 6 demonstrated much improvement, and 3 patients demonstrated minimal improvement. Only 1 patient showed no change in his condition. One additional patient stopped taking escitalopram after 5 weeks because of an absence of improvement in his state.

CONCLUSIONS

Escitalopram was well tolerated as treatment of VH in PD patients. This medication could be a promising optional therapy for this disturbance; however, further randomized controlled and bigger studies are necessary.

A review of adverse events linked to dopamine agonists in the treatment of Parkinson's disease

INTRODUCTION

Dopamine agonists are highly effective as adjunctive therapy to levodopa in advanced Parkinson's disease. These drugs have rapidly gained popularity as a monotherapy in the early stages of Parkinson's disease for patients less than 65-70 years old since they are about as effective as levodopa but patients demonstrate a lower tendency to develop motor complications. However, dopamine agonists could have peripheral and central side-effects which are often the reason for the discontinuation of the treatment.

AREAS COVERED

This article presents an overview of the efficacy and the potential negative effects related to the use of dopamine agonists in the treatment of Parkinson's disease.

EXPERT OPINION

Beyond the new generation non ergot dopamine agonists, no strong evidences allow the choice of a specific dopamine agonists for Parkinson 's disease treatment and by now dopamine agonists treatment should be tailored on specific adverse events profile.

The epigenetics of aging and neurodegeneration

Epigenetics is a quickly growing field encompassing mechanisms regulating gene expression that do not involve changes in the genotype. Epigenetics is of increasing relevance to neuroscience, with epigenetic mechanisms being implicated in brain development and neuronal differentiation, as well as in more dynamic processes related to cognition. Epigenetic regulation covers multiple levels of gene expression; from direct modifications of the DNA and histone tails, regulating the level of transcription, to interactions with messenger RNAs, regulating the level of translation. Importantly, epigenetic dysregulation currently garners much attention as a pivotal player in aging and age-related neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, and Huntington's disease, where it may mediate interactions between genetic and environmental risk factors, or directly interact with disease-specific pathological factors. We review current knowledge about the major epigenetic mechanisms, including DNA methylation and DNA demethylation, chromatin remodeling and non-coding RNAs, as well as the involvement of these mechanisms in normal aging and in the pathophysiology of the most common neurodegenerative diseases. Additionally, we examine the current state of epigenetics-based therapeutic strategies for these diseases, which either aim to restore the epigenetic homeostasis or skew it to a favorable direction to counter disease pathology. Finally, methodological challenges of epigenetic investigations and future perspectives are discussed.

Mapping cortical atrophy in Parkinson's disease patients with dementia

BACKGROUND

Cognitive impairment is very common in patients with Parkinson's disease (PD). Brain changes accompanying cognitive decline in PD are still not fully established.

METHODS

We applied cortical pattern matching and cortical thickness analyses to the three-dimensional T1-weighted brain MRI scans of 14 age-matched cognitively normal elderly (NC), 12 cognitively normal PD (PDC), and 11 PD dementia (PDD) subjects. We used linear regression models to investigate the effect of diagnosis on cortical thickness. All maps were adjusted for multiple comparisons using permutation testing with a threshold p < 0.01.

RESULTS

PDD showed significantly thinner bilateral sensorimotor, perisylvian, lateral parietal, as well as right posterior cingulate, parieto-occipital, inferior temporal and lateral frontal cortices relative to NC (left p(corrected) = 0.06, right p(corrected) = 0.009). PDD showed significantly thinner bilateral sensorimotor, right frontal and right parietal-occipital cortices relative to PDC (right p(corrected) = 0.05). The absolute difference in cortical thickness between PDD and the other diagnostic groups ranged from 3% to 19%.

CONCLUSION

Our data shows that cognitive decline in PD is associated with cortical atrophy. PDD subjects have the most widespread gray matter atrophy suggesting more cortical involvement as PD patients progress to dementia.

Risk factors for hallucinations in Parkinson's disease: results from a large prospective cohort study

The aim of this study was to identify risk factors for the development of hallucinations in patients with Parkinson's disease (PD). A broad range of motor and nonmotor features was assessed at baseline and during the following 5 years in 386 PD patients. Cross-sectional analyses of baseline data and longitudinal analyses of follow-up data were performed to identify risk factors for hallucinations in PD. Twenty-one percent of the patients had hallucinations at baseline, whereas 46% of the patients without hallucinations at baseline developed this feature during follow-up. Univariate survival analysis showed that older age, female sex, less education, higher age at onset, and more severe motor and cognitive impairment, depression, daytimes sleepiness, autonomic dysfunction, and motor fluctuations and dyskinesias, as well as higher daily levodopa dose, were associated with the risk of developing hallucinations. This largely corresponds with the features that were associated with the presence of hallucinations at baseline. In a stepwise regression model, older age at onset, female sex, excessive daytime sleepiness, autonomic dysfunction, and dyskinesias emerged as independent risk factors for developing hallucinations. Female sex, autonomic dysfunction, motor fluctuations, and dyskinesias have not been reported as risk factors in previous studies. These findings lend support to the notion that hallucinations in PD are caused by a combination of risk factors that are associated with (the interaction between) older age and more advanced disease. The identification of female sex as a risk factor for developing of hallucinations in PD is a new finding and should be verified in future studies.

Epigenetic programming of neurodegenerative diseases by an adverse environment

Experience and environment can critically influence the risk and progression of neurodegenerative disorders. Epigenetic mechanisms, such as miRNA expression, DNA methylation, and histone modifications, readily respond to experience and environmental factors. Here we propose that epigenetic regulation of gene expression and environmental modulation thereof may play a key role in the onset and course of common neurological conditions, including Alzheimer's disease, Parkinson's disease, Huntington's disease, and multiple sclerosis. For example, epigenetic mechanisms may mediate long-term responses to adverse experience, such as stress, to affect disease susceptibility and the course of neurodegenerative events. This review introduces the epigenetic components and their possible role in mediating neuropathological processes in response to stress. We argue that epigenetic modifications will affect neurodegenerative events through altered gene function. The study of epigenetic states in neurodegenerative diseases presents an opportunity to gain new insights into risk factors and pathogenic mechanisms. Moreover, research into epigenetic regulation of disease may revolutionize health care by opening new avenues of personalized, preventive and curative medicine.

Clinical review of treatment options for select nonmotor symptoms of Parkinson's disease

BACKGROUND

Parkinson's disease (PD) is associated with a host of nonmotor symptoms, including psychosis, cognitive impairment, depression, sleep disturbance, swallowing disorders, gastrointestinal symptoms, and autonomic dysfunction. The nonmotor symptoms of PD have the potential to be more debilitating than the motor features of the disorder.

OBJECTIVE

The aim of this article was to review treatment options for the nonmotor manifestations of PD, including pharmacologic and nonpharmacologic interventions.

METHODS

The PubMed and MEDLINE databases were searched for articles published in English between January 1966 and April 2010, using the terms Parkinson's disease, nonmotor, psychosis, hallucination, antipsychotic, cognitive impairment, dementia, depression, sleep disturbance, sleepiness, REM (rapid eye movement) sleep behavior disorder, dysphagia, swallowing disorder, sialorrhea, gastrointestinal, constipation, autonomic dysfunction, orthostatic hypotension, gastroparesis, erectile dysfunction, sexual dysfunction, and urinary dysfunction. Articles were selected for review if they were randomized controlled trials (RCTs), meta-analyses, or evidence-based reviews of treatment of patients with PD, and/or expert opinion regarding the treatment of nonmotor symptoms of PD.

RESULTS

A total of 148 articles, including RCTs, meta-analyses, and evidence-based reviews, were included in this review. The treatment of hallucinations or psychosis in PD should include a stepwise reduction in medications for motor symptoms, followed by the use of quetiapine or clozapine. Dementia may be treated with acetylcholinesterase inhibitors. Evidence is lacking concerning the optimal pharmacologic treatment for depression in PD, with expert opinions indicating selective serotonin reuptake inhibitors as the antidepressants of choice. However, the largest study to date found nortriptyline therapy to be efficacious compared with placebo, whereas paroxetine controlled release was not. A variety of sleep disturbances may plague a person with PD, and treatment must be individualized to the patient's specific sleep disturbance pattern and contributing factors. Swallowing disorders may lead to aspiration and pneumonia, and patients with dysphagia should be referred to a speech therapist for further evaluation and treatment. Orthostasis may be treated with nonpharmacologic interventions as well as pharmacologic treatments (eg, fludrocortisone, midodrine, indomethacin). Other autonomic symptoms are managed in a manner similar to that in patients without PD, although careful attention must be aimed at avoiding dopamine-blocking therapies in the treatment of gastrointestinal dysfunction and gastroparesis.

CONCLUSIONS

Various pharmacologic and nonpharmacologic strategies are available for the management of the nonmotor symptoms of PD. The challenges associated with nonmotor symptoms must not be forgotten in light of the motor symptoms of PD, and treatment of nonmotor symptoms should be encouraged.

Uso terapêutico dos canabinoides em psiquiatria

OBJETIVO: Revisar os principais avanços no potencial uso terapêutico de alguns compostos canabinoides em psiquiatria. MÉTODO: Foi realizada busca nos bancos de dado PubMed, SciELO e Lilacs e identificados estudos e revisões da literatura sobre o uso terapêutico dos canabinoides em psiquiatria, em particular canabidiol, rimonabanto, Δ9-tetraidrocanabinol e seus análogos. RESULTADOS: O canabidiol demonstrou apresentar potencial terapêutico como antipsicótico, ansiolítico, antidepressivo e em diversas outras condições. O Δ9-tetraidrocanabinol e seus análogos demonstraram efeitos ansiolíticos, na dependência de cannabis, bem como adjuvantes no tratamento de esquizofrenia, apesar de ainda carecerem de mais estudos. O rimonabanto demonstrou eficácia no tratamento de sintomas subjetivos e fisiológicos da intoxicação pela cannabis e como adjuvante no tratamento do tabagismo. Os potenciais efeitos colaterais, de induzir depressão e ansiedade limitaram o uso clínico deste antagonista CB1. CONCLUSÃO: Os canabinoides têm demonstrado que podem ter amplo interesse terapêutico em psiquiatria, porém mais estudos controlados são necessários para confirmar estes achados e determinar a segurança destes compostos.

Cannabidiol for the treatment of psychosis in Parkinson's disease

The management of psychosis in Parkinson's disease (PD) has been considered a great challenge for clinicians and there is a need for new pharmacological intervention. Previously an antipsychotic and neuroprotective effect of Cannabidiol (CBD) has been suggested. Therefore, the aim of the present study was to directly evaluate for the first time, the efficacy, tolerability and safety of CBD on PD patients with psychotic symptoms. This was an open-label pilot study. Six consecutive outpatients (four men and two women) with the diagnosis of PD and who had psychosis for at least 3 months were selected for the study. All patients received CBD in flexible dose (started with an oral dose of 150 mg/day) for 4 weeks, in addition to their usual therapy. The psychotic symptoms evaluated by the Brief Psychiatric Rating Scale and the Parkinson Psychosis Questionnaire showed a significant decrease under CBD treatment. CBD did not worsen the motor function and decreased the total scores of the Unified Parkinson's Disease Rating Scale. No adverse effect was observed during the treatment. These preliminary data suggest that CBD may be effective, safe and well tolerated for the treatment of the psychosis in PD.

Perfusion magnetic resonance imaging in psychiatry

INTRODUCTION

Cerebral perfusion imaging using magnetic resonance imaging (MRI) is widely used in the research and clinical fields to assess the profound changes in blood flow related to ischemic events such as acute stroke, chronic steno-occlusive disease, vasospasm, and abnormal vessel formations from congenital conditions or tumoral neovascularity. With continuing improvements in the precision of MRI-based perfusion techniques, it is increasingly feasible to use this tool in the study of the subtle brain perfusion changes occurring in psychiatric illnesses. This article aims to review the existing literature on applications of perfusion MRI in psychiatric disorder and substance abuse research. The article also provides a brief introductory overview of dynamic susceptibility contrast MRI and arterial spin labeling techniques. An outlook of necessary steps to bring perfusion MRI into the realm of clinical psychiatry as a diagnostic tool is brought forth. Opportunities for research in unexplored disorders and with higher field strengths are briefly examined.

METHODS

PubMed, ISI Web of Knowledge & Scopus were used to search the literature and cross reference several neuropsychiatric disorders with a search term construct, including "magnetic resonance imaging," "dynamic susceptibility contrast," "arterial spin labeling," perfusion or "cerebral blood flow" or "cerebral blood volume" or "mean transit time." The list of disorders used in the search included schizophrenia, depression and bipolar disorder, dementia and Alzheimer's disease, Parkinson's disease, posttraumatic stress disorder, autism, Asperger disease, attention deficit, Tourette syndrome, obsessive-compulsive disorder, Huntington's disease, bulimia nervosa, anorexia nervosa, and substance abuse. For each disorder for which perfusion MRI studies were found, a brief overview of the disorder symptoms, treatment, prevalence, and existing models is provided, and previous findings from nuclear medicine-based perfusion imaging are overviewed. Findings of perfusion MRI studies are then summarized, and overlap of findings are discussed. Overarching conclusions are made, or an outlook for future work in the area is offered, where appropriate.

RESULTS

Despite the now fairly broad availability of perfusion MRI, only a limited number of studies were found using this technology. The search produced 13 studies of schizophrenia, 7 studies in major depression, 12 studies in Alzheimer's disease, and 2 studies in Parkinson's disease. Drug abuse and other disorders have mainly been studied with nuclear medicine-based perfusion imaging. The literature concerning the use of perfusion imaging in psychiatry has not been reviewed in the last 5 years or more. The use of MRI for perfusion measurements in psychiatry has not been reviewed in 10 years.

CONCLUSIONS

Although MRI-based perfusion imaging in psychiatry has mainly been used as a research tool, a path is progressively being cleared for its application in clinical diagnostic and treatment monitoring. The precision of perfusion MRI methods now rivals that of nuclear medicine-based perfusion imaging techniques. Because of their noninvasive nature, arterial spin labeling methods have gained popularity in studies of neuropsychiatric disorders such as schizophrenia, depression, Alzheimer's, and Parkinson's diseases. Perfusion imaging measurements have yet to be included within the diagnostic criteria of neuropsychiatric disorders despite having shown to have great discriminant power in specific disorders. As this young methodology continues to improve and research studies demonstrate the correlation of measured perfusion abnormalities to microcirculatory abnormalities and neuropsychiatric symptomatology, the idea of including such a test within diagnostic criteria for certain mental illnesses becomes increasingly plausible.

The safety of dopamine agonists in the treatment of Parkinson's disease

Dopamine agonists are highly effective as adjunctive therapy to levodopa in advanced Parkinson's disease. These drugs have rapidly gained popularity as a monotherapy in the early stages of Parkinson's disease for patients < 65-70 years old, because they are about as effective as levodopa, but patients demonstrate a lower tendency to develop motor complications. However, dopamine agonists could have peripheral and central side effects, which are often the reason for the discontinuation of the treatment. This review focuses on the potential negative effects related to the use of dopamine agonists in the treatment of Parkinson's disease.

Psychosis in Parkinson's disease

Psychosis is common in Parkinson's disease (PD), particularly in its later stages. The symptoms range from comparatively minor illusions, vivid dreams, and occasional, non-disturbing visual hallucinations to frank psychosis. The pathogenesis of psychosis in PD is not fully known. Management of psychosis in PD requires a multidisciplinary approach. Some of the newer atypical antipsychotics are effective against psychosis with no significant worsening of PD. Psychosis in PD is associated with poor quality of life for patients and the carers.

Psychotic symptoms in Parkinson’s disease

Psychotic symptoms are common in Parkinson's disease (PD) and occur in at least 20% of medication-treated patients. Benign visual hallucinations usually appear earlier, while malignant hallucinations, confusional states, delusions, paranoid beliefs, agitation, and delirium become more frequent with disease progression. Virtually all antiparkinsonian drugs may produce psychotic symptoms. Cognitive impairment, increased age, disease duration and severity, depression, and sleep disorders have been consistently identified as independent risk factors for their development. Although the precise pathoetiologic mechanisms remain unknown, we review evidence that links ventral dopaminergic pathway dysfunction (overactivity) together with the involvement of other neurotransmitter system imbalances as likely contributors. The clinical importance of the proposed mechanism is that successful management of psychotic symptoms in PD may rely on a multitarget approach to restore neurotransmitter imbalances rather than focusing exclusively on the dopaminergic dysfunction.

Factors associated with drug-induced visual hallucinations in Parkinson's disease

AIMS

Visual hallucinations are common in medication-treated Parkinson's disease (PD) patients. Although their etiology is unknown several factors seem to be involved in their pathogenesis. The aim of this study was to identify possible risk factors and determine clinical characteristics associated with the development of visual hallucinations in PD.

METHODS

166 consecutive patients fulfilling clinical criteria for PD were studied. During a semi-structured interview, demographic characteristics and clinical variables were recorded. Motor, cognitive and psychiatric status was also assessed. Patients with and without visual hallucinations were compared using non-parametric tests, and logistic regression was applied to significant data.

RESULTS

During the month before evaluation 20.4% of our patients experienced visual hallucinations (11.4% benign, 9% malignant). Logistic regression analysis identified three factors independently associated with visual hallucinations: long duration of Parkinson's disease, dementia, and disease severity as measured by the UPDRS total score.

CONCLUSIONS

Our findings indicate that apart from well established risk factors such as cognitive impairment and disease duration, disease severity is also important for the development of visual hallucinations in PD. Furthermore, the presence of bradykinesia and instability, the absence of tremor and the severity of rigidity and bradykinesia (limb and axial) may act as cofactors.

Double-blind, placebo-controlled, unforced titration parallel trial of quetiapine for dopaminergic-induced hallucinations in Parkinson's disease

We completed a single site, double-blind, placebo-controlled, parallel design study of quetiapine for hallucinations in PD. Thirty-one subjects with PD and prominent visual hallucinations and Mini-Mental State Examination score >21 were randomly assigned in a 2:1 drug to placebo ratio, up to 200 mg daily of quetiapine or matching placebo given in two doses. They were seen at 3 weeks (100 mg/day) and 12 weeks (200 mg/day, with optional dose reduction). Evaluation included the Unified Parkinson's Disease Rating Scale (UPDRS), the Baylor PD Hallucination Questionnaire, and a battery of neuropsychological tests. The demographics between subjects randomized to drug (n = 21) vs. placebo (n = 10) were similar. The final dose of active drug was 200 (n = 11), 150 (n = 2), 100 (n = 3), and 75 (n = 1) mg per day. All placebo subjects were on the equivalent of 200 mg per day. The UPDRS Activities of Daily Living and Motor scores did not significantly change compared to placebo. Compared to placebo, there were no significant changes in our hallucination questionnaire, the Brief Psychiatric Rating Scale (BPRS), or question 12 (hallucination item) of the BPRS. There were no significant changes on any of the neuropsychological measures. Adverse events on drug included sedation (n = 9), but no drug-related adverse events precipitated discontinuation and none were rated as serious. Quetiapine, up to 200 mg daily, was well tolerated and did not worsen UPDRS scores; however, there was no significant improvement in psychosis rating scales compared to placebo. Larger doses of drug and greater sample sizes might be considered in future studies.

Psychiatric aspects of Parkinson's disease--an update

In patients with Parkinson's disease (PD) disturbances of mental state constitute some of the most difficult treatment challenges of advanced disease, often limiting effective treatment of motor symptoms and leading to increased disability and poor quality of life. This article provides an update on the current knowledge of these complications and the use of old and new drugs in their management. Mental state alterations in PD include depression, anxiety, cognitive impairment, apathy, and treatment-related psychiatric symptoms. The latter range from vivid dreams and hallucinations to delusions, manic symptoms, hypersexuality, dopamine dysregulation syndrome and delirium. While some of these symptoms may be alleviated by anti-parkinsonian medication, especially if they are off-period related, treatment-related phenomena are usually exacerbated by increasing the number or dosage of antiparkinsonian drugs. Elimination of exacerbating factors and simplification of drug regimes are the first and most important steps in improvement of such symptoms. However, the advent of atypical antipsychotics such as clozapine has dramatically helped the management of treatment-related psychiatric complications in PD. In patients with dementia associated with PD cognitive functioning and behavioural problems appear to respond to cholinesterase inhibitors, such as rivastigmine or donepezil. Depression is a common problem in early as well as advanced PD, and selective serotonin reuptake inhibitors, reboxetine, and tricyclic antidepressants have been reported to be effective and well tolerated antidepressants. Randomised, controlled studies are required to assess the differential efficacy and tolerability of antidepressants in patients with PD, including the newer antidepressants with serotonergic and noradrenergic properties.

Pharmacologic management of psychosis in the elderly: a critical review

OBJECTIVE

Psychotic symptoms are seen in numerous psychiatric illnesses afflicting the elderly. This article reviews the efficacy of the pharmacologic management of psychotic symptoms in primary psychotic disorders, affective disorders, and neurodegenerative disorders.

METHOD

A comprehensive literature review.

RESULTS

Evidence to support the use of pharmacologic interventions to manage psychotic symptoms in elderly patients afflicted with primary psychotic disorders and affective disorders is limited by the absence of randomized, placebo-controlled trials (RCTs). The use of low-dose clozapine is supported by RCTs in Parkinson's disease. The efficacy of risperidone and olanzapine for the treatment of psychotic symptoms has been demonstrated by large RCTs in Alzheimer's disease.

CONCLUSION

There is evidence of the efficacy of antipsychotic medications to manage psychotic symptoms in elderly patients. However, the absence of published evidence from RCTs in primary psychotic and affective disorders, and the limited evidence in the neurodegenerative illnesses, is notable.

Olanzapine treatment for dopaminergic-induced hallucinations

Atypical antipsychotic medications with lower affinities for D2 receptors are considered useful alternatives to treat drug-induced hallucinations in Parkinson's disease (PD). We conducted a double-blind, placebo-controlled, unforced titration, parallel design study (2:1 drug to placebo randomization ratio) using olanzapine (2.5-10 mg/day to effect) in 30 PD patients with drug-induced hallucinations. We performed an extensive battery of neuropsychological tests, the Unified Parkinson's Disease Rating Scale (UPDRS), assessments of on and off time at baseline and at 9 weeks after starting the medication. Sixteen patients on olanzapine (mean dose, 4.6 mg/night) and 11 on placebo completed the study. Compared with placebo, performance on the UPDRS item 2 (thought disorder), and a structured interview for hallucinations, both tended to improve on drug but neither reached statistical significance. A neuropsychological test battery did not show any significant differences. Total on UPDRS motor scores (P < 0.05) and timed tapping (P < 0.01) worsened while on drug compared to placebo. Bradykinesia (P < 0.01) and gait (P < 0.001) items on the UPDRS largely accounted for this deterioration. After completion of the study, 8 of 16 patients randomly assigned to drug continued olanzapine at a mean dose of 2.4 mg/day. However, at the last recorded visit only 5 of 24 (20.8%) of all patients exposed to drug (including those originally randomly assigned to placebo) remained on olanzapine. In patients with PD, low-dose olanzapine did not significantly improve hallucinations but did worsen motor function.

Rivastigmine in the treatment of parkinsonian psychosis and cognitive impairment: preliminary findings from an open trial

This open study assessed the ability of rivastigmine to treat the neuropsychiatric complications of advanced Parkinson's disease. In a group of 12 patients, hallucinations, sleep disturbance, and carer distress were all improved and cognitive performance significantly enhanced by the drug.

Treatment of the special patient with schizophrenia

Special patient populations with schizophrenia have received little attention. These populations include adolescents, the elderly, substance abusers, and patients who are considered treatment-resistant. Interest in these populations is rapidly growing, especially with regard to their treatment with second-generation antipsychotics. This article describes the treatment of special patient populations and summarizes the research that has been done in this field.

Prospective study of hallucinations and delusions in Parkinson's disease

OBJECTIVE

This study was undertaken to determine the prevalence of hallucinations and delusions in Parkinson's disease, to describe such symptoms phenomenologically, and possibly to determine factors associated with their development. In addition, the role of the visual system in relation to visual hallucinations was examined.

METHOD

102 consecutive patients diagnosed with strictly defined Parkinson's disease were examined for the presence of hallucinations and delusions and assessed for visual acuity, cognition, depression using the geriatric depression scale, disease severity as measured by the UPDRS, and other clinical variables.

RESULTS

Of 102 consecutive patients, 29.4% (n=30) had hallucinations or delusions, four (3.9%) were determined to be psychotic due solely to delirium and were excluded from further analysis. Of the 98 remaining patients, 26.5% (n=26) had visual hallucinations. Among these, one patient also had delusions, two had auditory hallucinations, and one had gustatory hallucinations. Visual hallucinations were significantly associated with worse visual acuity, lower cognitive score, higher depression score, and worse disease severity. Hallucinations were not associated with history of psychiatric disease, dose or duration of levodopa or other antiparkinsonian medication treatment, or duration of illness.

CONCLUSIONS

Visual hallucinations are common symptoms in Parkinson's disease and are most likely of multifactorial origin. Although higher doses of levodopa are known to be related clinically to hallucinations in individual patients, the results suggest that several underlying characteristics of patients with Parkinson's disease (disease severity, dementia, depression, worse visual acuity) may be more important determinants of which patients experience hallucinations. The data also provide preliminary evidence that abnormality of the visual system may be related to visual hallucinations in Parkinson's disease, as has been found in other disorders with visual hallucinations.

Clinical Lewy body syndromes

Lewy bodies are spherical, intracytoplasmic, eosinophilic, neuronal inclusions comprising abnormally truncated and phosphorylated intermediate neurofilament proteins, alpha-synuclein, ubiquitin, and associated enzymes. The clinical presentation of LB disease varies according to the site of LB formation and associated neuronal loss. Three main clinicopathological syndromes have been described--movement disorder, autonomic failure, and dementia. Parkinsonism is the most common presentation of LB disease developing in middle life. In older patients, a mixture of cognitive, autonomic, and motor dysfunction is more common. Dementia with LB (DLB) is a relatively recently described clinicopathological syndrome that accounts for up to 20% of all cases of dementia in old age. Patients, typically in their seventh and eighth decades, have LB pathology in cortical neurons as well as in the brain stem. LB disease should be considered in the differential diagnosis of a wide range of clinical presentations including episodic disturbances of consciousness, syncope, sleep disorders, and unexplained delirium.

Spectrum of Parkinson's disease, Parkinson's dementia, and Lewy body dementia

Dementia occurs more commonly in individuals with Parkinson's disease (PD) than in the age-matched general population. Dementia in PD may result from a mixture of cortical and subcortical dementia syndromes caused by a variety of underlying pathologic processes and neurochemical deficits. A primary dementia syndrome has been described that shares several pathologic and clinical characteristics with PD. Dementia with Lewy bodies (DLB) accounts for 15% to 20% of all dementia syndromes in old age, which makes it second only to Alzheimer's disease in prevalence. The relationship between dementia in PD and DLB has not been fully resolved but may be considered useful in terms of neuropathologic substrate, clinical features, and response to treatment.

Neuropsychiatric aspects of Parkinson's disease

Previous studies of the neuropsychiatric aspects of Parkinson"s disease were frequently methodologically inadequate. Small sample sizes, selection bias, lack of diagnostic criteria of Parkinson"s disease, different definitions and assessment of neuropsychiatric symptoms, and lack of control groups seriously questioned the validity of and ability to generalize the results from many studies. During the past decade, however, several of these methodological issues have been addressed. Recent studies have found that mild cognitive impairment is very common, and dementia, depression, and psychotic symptoms develop in a large proportion of patients. Neuropsychiatric symptoms are important determinants of mortality and disease progression, as well as of the patients quality of life and course of disease, caregiver distress, and nursing home admission. Few adequately designed treatment trials have been published, but available evidence suggests that depression and hallucinations may be effectively treated using new antidepressants and atypical antipsychotic agents without worsening of parkinsonism.

Atypical antipsychotics in older adults

Psychotic symptoms are common in older adults and reflect a variety of psychiatric and medical conditions. Antipsychotic drugs form the core of the treatment of these symptoms; however, treatment of the elderly is complicated by a high frequency of comorbid medical illnesses, risk of side effects, and age-related changes in pharmacodynamics and pharmacokinetics. The superior safety and efficacy of atypical antipsychotics makes them first-line agents for managing psychotic patients with schizophrenia. Their uses now extend to other conditions such as schizoaffective disorders, delusional disorder, and mood disorders with psychotic features. Although the drugs have been studied extensively in young subjects, well-designed, double-blind, placebo-controlled studies are relatively lacking in the elderly. Our knowledge of their safety, efficacy and dosage in older adults is based on a few studies with small samples or extrapolated from studies of younger patients. Several psychiatric and medical conditions that are associated with psychotic symptoms in older people are reviewed, as well as how these patients may benefit from treatment with these agents.

Reliability and validity of the Overt Agitation Severity Scale in adult psychiatric inpatients

An instrument, that validly and reliably identifies and measures agitation is required to evaluate environmental modifications, interpersonal strategies, psychopharmacological interventions, directed toward managing these commonly occurring and highly-disabling emotions and behavior. The conceptualization of agitation on a continuum from anxiety to aggression provides a practical framework for guiding clinical practice toward the early identification and intervention of agitation. The results of this study established the reliability and validity of the Overt Agitation Severity Scale (OASS) in measuring agitation severity in young adult psychiatric inpatients based on objectifiable vocalizations and motoric upper and lower body behaviors. The OASS differs from other agitation scales in its ability to capture both the intensity and frequency of observable behavioral manifestations of agitation, as opposed to subjective interpretations and a diffuse range of symptoms and problem behaviors.

Geriatric psychosis

This article reviews diagnostic and treatment issues which merit special consideration in the elderly psychotic patient. Psychoses are serious psychiatric disorders and can present in different forms in the elderly. The important ones include schizophrenia, psychosis in patients with dementia, psychosis in patients with depression and delusional disorder. Typical and atypical antipsychotic medications remain the treatment of choice for psychotic disorders but special considerations are warranted when prescribed to elderly patients. We have highlighted differences between younger and older adults in terms of clinical characteristics and treatment of psychotic disorders.