Minor Hallucinations Research Articles

A pilot feasibility study comparing large language models in extracting key information from ICU patient text records from an Irish population

BackgroundArtificial intelligence, through improved data management and automated summarisation, has the potential to enhance intensive care unit (ICU) care. Large language models (LLMs) can interrogate and summarise large volumes of medical notes to create succinct discharge summaries. In this study, we aim to investigate the potential of LLMs to accurately and concisely synthesise ICU discharge summaries.MethodsAnonymised clinical notes from ICU admissions were used to train and validate a prompting structure in three separate LLMs (ChatGPT, GPT-4 API and Llama 2) to generate concise clinical summaries. Summaries were adjudicated by staff intensivists on ability to identify and appropriately order a pre-defined list of important clinical events as well as readability, organisation, succinctness, and overall rank.ResultsIn the development phase, text from five ICU episodes was used to develop a series of prompts to best capture clinical summaries. In the testing phase, a summary produced by each LLM from an additional six ICU episodes was utilised for evaluation. Overall ability to identify a pre-defined list of important clinical events in the summary was 41.5 ± 15.2% for GPT-4 API, 19.2 ± 20.9% for ChatGPT and 16.5 ± 14.1% for Llama2 (p = 0.002). GPT-4 API followed by ChatGPT had the highest score to appropriately order a pre-defined list of important clinical events in the summary as well as readability, organisation, succinctness, and overall rank, whilst Llama2 scored lowest for all. GPT-4 API produced minor hallucinations, which were not present in the other models.ConclusionDifferences exist in large language model performance in readability, organisation, succinctness, and sequencing of clinical events compared to others. All encountered issues with narrative coherence and omitted key clinical data and only moderately captured all clinically meaningful data in the correct order. However, these technologies suggest future potential for creating succinct discharge summaries.

Exploring the Spectrum of Visual Illusions and Other Minor Hallucinations in Patients with Parkinson's Disease in Lithuania.

Background and Objectives: Parkinson's disease (PD) is associated with various non-motor symptoms, including minor hallucinations, comprising visual illusions and presence and passage hallucinations. Despite their occurrence, even in newly diagnosed PD patients, data regarding the prevalence and characteristics of minor hallucinations, visual illusions in particular, remain limited. The aim of this study was to address this knowledge gap by assessing the prevalence of minor hallucinations in PD patients, with a focus on visual illusions. Materials and Methods: In this prospective pilot study, we enrolled 35 PD patients without dementia and 35 age- and gender-matched PD-unaffected individuals. Cognitive function was assessed using the Montreal Cognitive Assessment, clinical data were collected, and all subjects were assessed via questionnaires regarding 20 types of visual illusions and other minor hallucinations. Results: The prevalence of minor hallucinations was significantly higher among PD patients compared to controls (45.7% vs. 11.4%, p = 0.003). PD patients reported visual illusions and presence hallucinations more frequently than the controls (37.1% vs. 8.6% and 22.9% vs. 2.9%, p = 0.009 and p = 0.028, respectively), with no significant difference in passage hallucinations (20% vs. 8.6%, p = 0.306). In the PD group, the most frequently observed visual illusions were complex visual illusions, kinetopsia, and pelopsia; the latter was also the most common visual illusion in the control group. PD patients experiencing visual illusions were more likely to report presence hallucinations compared to patients without visual illusions (53.8% vs. 4.5%, p = 0.002); no significant differences in other clinical characteristics were found. Conclusions: Minor hallucinations are a common phenomenon among PD patients without dementia, with a higher prevalence than among healthy controls. Visual illusions are the most prevalent type of minor hallucinations, affecting more than a third of PD patients, with complex visual illusions, kinetopsia, and pelopsia being the most frequently reported types.

Pycnogenol® improves cognitive function in post-stroke patients: a 6 month-study.

This pilot study in post-stroke patients evaluated the effects of supplementation with Pycnogenol® on alterations in cognitive functions (COFU) over a period of 6 months, starting 4 weeks after the stroke. The effects of supplementation - possibly acting on residual brain edema, on global cognitive function, attention and on mental performance - were studied. A control group used standard management (SM) and the other group added Pycnogenol®, 150 mg daily to SM. 38 post-stroke patients completed the 6-month-study, 20 in the Pycnogenol® group and 18 in the control group. No side effects were observed with the supplement. The tolerability was very good. The patients included into the two groups were comparable for age, sex and clinical distribution. There were 2 dropouts in the control group, due to non-medical problems. Main COFU parameters (assessed by a cognitive questionnaire) were significantly improved (all single items) with the supplement compared to controls (P<0.05). Additional observations indicate that Pycnogenol® patients experienced significantly less mini-accidents (including falls) than controls (P<0.05). The incidences of (minor) psychotic episodes or conflicts and distress and other problems including rare occurrence of minor hallucinations, were lower with the supplementation than in controls (P<0.05). Single observations concerning daily tasks indicated a better effect of Pycnogenol® compared to controls (P<0.05). Plasma free radicals also decreased significantly with the supplement in comparison to controls (P<0.05). Globally, supplemented subjects had a better recovery than controls. In post-stroke subjects, Pycnogenol® supplementation resulted in better recovery outcome and faster COFU 'normalization' after the stroke in comparison with SM; it can be considered a safe, manageable post-stroke, adjuvant management possibly reducing local brain edema. Nevertheless, more patients and a longer period of evaluation are needed to confirm these results.

Global brain analysis of minor hallucinations in Parkinson's disease using EEG and MRI data.

Visual hallucination is a prevalent psychiatric disorder characterized by the occurrence of false visual perceptions due to misinterpretation in the brain. Individuals with Parkinson's disease often experience both minor and complex visual hallucinations. The underlying mechanism of complex visual hallucinations in Parkinson's patients is commonly attributed to dysfunction in the visual pathway and attention network. However, there is limited research on the mechanism of minor hallucinations. To address this gap, we conducted an experiment involving 13 Parkinson's patients with minor hallucinations, 13 Parkinson's patients without hallucinations, and 13 healthy elderly individuals. We collected and analyzed EEG and MRI data. Furthermore, we utilized EEG data from abnormal brain regions to train a machine learning model to determine whether the abnormal EEG data were associated with minor hallucinations. Our findings revealed that Parkinson's patients with minor hallucinations exhibited excessive activation of cortical excitability, an imbalanced interaction between the attention network and the default network, and disruption in the connection between these networks. These findings is similar to the mechanism observed in complex visual hallucinations. The visual reconstruction of one patient experiencing hallucinations yields results that differ from those observed in subjects without such symptoms. The visual reconstruction results demonstrated significant differences between Parkinson's patients with hallucinations and healthy subjects. This suggests that visual reconstruction techniques may offer a means of evaluating hallucinations.

Parkinson disease psychosis: from phenomenology to neurobiological mechanisms.

Parkinson disease (PD) psychosis (PDP) is a spectrum of illusions, hallucinations and delusions that are associated with PD throughout its disease course. Psychotic phenomena can manifest from the earliest stages of PD and might follow a continuum from minor hallucinations to structured hallucinations and delusions. Initially, PDP was considered to be a complication associated with dopaminergic drug use. However, subsequent research has provided evidence that PDP arises from the progression of brain alterations caused by PD itself, coupled with the use of dopaminergic drugs. The combined dysfunction of attentional control systems, sensory processing, limbic structures, the default mode network and thalamocortical connections provides a conceptual framework to explain how new incoming stimuli are incorrectly categorized, and how aberrant hierarchical predictive processing can produce false percepts that intrude into the stream of consciousness. The past decade has seen the publication of new data on the phenomenology and neurobiological basis of PDP from the initial stages of the disease, as well as the neurotransmitter systems involved in PDP initiation and progression. In this Review, we discuss the latest clinical, neuroimaging and neurochemical evidence that could aid early identification of psychotic phenomena in PD and inform the discovery of new therapeutic targets and strategies.

Functional Brain Networks of Minor and Well-Structured Major Hallucinations in Parkinson's Disease.

Minor hallucinations (mHs) and well-structured major hallucinations (MHs) are common symptoms of Parkinson's disease (PD) psychosis. To investigate the resting-state networks (RSNs) in patients with PD without hallucinations (PD-nH), with mH (PD-mH), and with MH (PD-MH). A total of 73 patients with PD were enrolled (27 PD-nH, 23 PD-mH, and 23 PD-MH). Using seed-based functional connectivity analyses, we investigated the RSNs supposedly related to hallucinations in PD: the default mode network (DMN), executive control network (ECN), dorsal attention network (DAN), ventral attention network (VAN), and visual network (VN). We compared the cognitive function and RSN connectivity among the three groups. In addition, we performed a seed-to-seed analysis to examine the inter-network connectivity within each group using the corresponding RSN seeds. PD-MH group had lower test scores for attention and visuospatial functions compared with those in the other groups. The connectivity of the right intracalcarine cortex within the DAN was lower in the PD-MH group than in the others. The PD-mH and PD-MH groups showed higher connectivity in the left orbitofrontal cortex within DMN compared with the PD-nH group, whereas the connectivity was lower in the right middle frontal gyrus (MFG) within ECN, precuneus cortex within VAN, right middle temporal gyrus and precuneus cortex within DAN, and left MFG within VN. The PD-mH and PD-MH groups showed different inter-network connectivity between the five RSNs, especially regarding DAN connectivity. DAN dysfunction may be a key factor in the progression from mH to MH in patients with PD. © 2023 International Parkinson and Movement Disorder Society.

Clinical Manifestations.

Visual hallucinations (VH) phenomenology in Lewy Body Disease (LBD) is heterogenous, including minor phenomena (passage, presence, illusions) and complex hallucinations. Neural substrates and mechanisms involved are still unclear. Here we investigated grey matter (GM) alterations associated with minor (MVH) and complex VH (CVH). LBD patients (n = 28) with VH and Healthy controls (HC-n = 20) underwent MRI. We administered the North East Visual Hallucinations Interview (NEVHI), a semi-structured interview assessing the phenomenology of VH, their duration and frequency. VH were clustered in MVH and CVH and treated as a patient's trait. First we compared GM volume of LBD and HC. Then, multiple regressions were performed to disclose alterations associated with the duration, frequency and severity of MVH and CVH, including the opposite VH domain, total intracranial volume (TIV) and MMSE as nuisance regressors. We found a decreased GM volume in the bilateral fusiform gyrus (FG), in the left posterior cingulate and in the right inferior frontal gyrus in LBD compared to HC. We also found that CVH duration was negatively associated with GM volume in the left FG. We did not find any association with MVH phenomenology. LBD patients showed GM alterations in ventral-visual-stream, default-mode-network and inhibitory regions compared to HC. Although the LBD versus HC comparison is not specific to VH, the regions identified have been implicated in VH in previous studies suggesting they may represent structural hallmarks of functional alterations in networks contributing to VH. When the association with VH phenomenology was tested, we did not find GM alterations associated with MVH. It is likely that these phenomena might be not associated with structural alterations but with functional alterations within visual networks. CVH were instead associated with decreased GM in FG. The atrophy in the FG may lead to a spontaneous activation of this region that sustain CVH duration, accounting for VH content (D'Antonio et al., 2022). These alterations may represent the predisposing condition to VH in LBD. According to the hodotopic model, VH phenomenology may help identify brain regions implicated and might reveal the substrates for cortical region/network dysfunctions occurring during VH state (ffytche et al., 2008).

FC20: Prevalence, Incidence, and Clinical Features of Lewy Body Dementia in the South Eastern of Spain

Background:Lewy body dementia (LBD) is the second most common degenerative dementia in people over 65 (1,2). LBD is underdiagnosed, with only one third of patients correctly diagnosed in daily clinical practice (3); data on the distribution of the disease are scarce. Our study was designed to measure the incidence, prevalence and clinical characteristics of LBD in south-eastern Spain. Healthcare system in Spain is free and universal.Methods:Prospective epidemiological study of LBD in San Vicente del Raspeig between October 18, 2021, and October 17, 2022. The total population aged 60 or over based on the 2019 census was 11445 inhabitants (5227 males, 6218 females). Diagnosis of LBD was based on 2017 McKeith criteria. Only “probable” cases were registered for greater diagnostic certainty. Incidence was studied for the one-year period. Collected data included gender, age, cardinal symptoms for LBD, abnormal biomarkers, neuropsychiatric symptoms, medical treatment, years from diagnosis and GDS score (Reisberg) in the last visit. Protocol was approved by the ethical committee.Results:Global prevalence was 0.67% among the population over 60. Annual incidence was 3.2/1000 person-year.Mean age of prevalent cases was 78 years (SD 7.5). 68.8% were studied with at least one biomarker (mainly 123I-ioflupane and less frequent polysomnography or MIBG gammagraphy); most suffered 2 or 3 core symptoms (79.2%) (in descending order: parkinsonism, visual hallucinations, rapid eye movement sleep behavior disorder and fluctuations). Two out of five prevalent cases were in an early phase of the disease: 22.1% in mild cognitive impairment (MCI) and 16.9 % in mild dementia. Mean me of disease was 1.9 years (SD 2.2). Other neuropsychiatric symptoms appeared in up to 74% of patients (apathy 18,2%, anxiety 19,5%, depression 23,4%, minor hallucinations 22%, delusions 17%, auditory and tactile hallucinations 1,2%).Conclusions:Prevalence is in line with previous reports. Higher incidence than previously reported may be due to high attention on MCI-LBD and our expertise as a referral Memory Unit. We found a wide dominance of aged women and high prevalence of neuropsychiatric symptoms.

Minor hallucinations in Parkinson's disease with probable rapid eye movement sleep behavior disorder.

Rapid eye movement sleep behavior disorder (RBD) and minor hallucinations (MHs) are prevalent nonmotor symptoms in Parkinson's disease (PD). The purpose of this study was to explore the association of MHs in PD patients with probable RBD (pRBD). This cross-sectional study included 291 patients diagnosed with PD. Patients who scored 6 or higher on the Rapid Eye Movement Behavior Disorder (RBD) Screening Questionnaire were defined as pRBD. A comprehensive evaluation was performed for all patients, including the collection of demographic information, clinical assessment, and MH features. Among the 291 PD patients, 69 (23.7%) had pRBD. MHs were observed in 35 (50.7%) patients with pRBD, significantly higher than 29.7% in patients without RBD (p = 0.015). The main type of MHs in pRBD was presence hallucinations with variable content. Patients with pRBD and MHs tended to be older, had a longer disease duration, and were more likely to take levodopa or dopamine-receptor agonists. Besides, the pRBD with MHs group had higher scores on the Nonmotor Symptoms Questionnaire (NMS-Quest) and Hamilton Anxiety Scale (HAMA). Binary logistic regression analysis revealed that longer disease duration and higher NMS-Quest scores were associated with MHs in PD patients with pRBD. A high prevalence of MHs was observed in PD patients with pRBD. The main type of MHs in pRBD was presence hallucinations. MHs in PD with RBD are mainly associated with disease duration and severity of nonmotor symptoms. These findings provide new insights into the interaction between MHs and RBD.

Minor hallucinations in early Parkinson’s disease: are they benign?

Minor hallucinations in early Parkinson’s disease: are they benign?

Theta oscillations and minor hallucinations in Parkinson’s disease reveal decrease in frontal lobe functions and later cognitive decline

Theta oscillations and minor hallucinations in Parkinson’s disease reveal decrease in frontal lobe functions and later cognitive decline

Risk of Psychosis among those with Parkinson’s disease with and without Minor Hallucinations (P6-11.010)

Risk of Psychosis among those with Parkinson’s disease with and without Minor Hallucinations (P6-11.010)

Clinical features of minor hallucinations in different phenotypes of Parkinson's disease: A cross-sectional study.

Minor hallucinations (MHs) are the most common psychiatric symptom associated with Parkinson's disease (PDPsy), but little is known about their characteristics in different motor phenotypes, especially postural instability gait difficulty (PIGD). The aim of this study was to explore the clinical features of MHs in different subtypes of PD. In this cross-sectional study, 213 patients with Parkinson's disease (PD) were recruited, and the data obtained included comprehensive demographics, motor subtypes, clinical scale scores, and MH contents. Motor subtypes were classified as tremor-dominant (TD), PIGD or indeterminate according to Stebbins' method. A total of 213 PD patients were included: 90 (42.3%) TD patients, 98 (46.0%) PIGD patients and 25 (11.7%) indeterminate. In total, 70 (32.9%) patients experienced MHs. Compared to patients with the TD phenotype, we found that patients with the PIGD phenotype had more severe motor and nonmotor symptoms. They also had a higher incidence of visual illusions (VIs) and a shorter MH latency. Our study demonstrated that compared to patients with the TD phenotype, patients with the PIGD phenotype had a higher incidence of MHs, especially VIs, which may lead to a higher incidence of visual hallucinations (VHs). They also had a shorter latency of MHs than patients with the TD phenotype, suggesting an earlier onset of MHs and a worse prognosis.

The role of attentional control over interference in minor hallucinations in Parkinson’s disease

BackgroundMinor hallucinations in Parkinson's disease are associated with connectivity changes in attentional networks and increased risk of structured hallucinations. However, the clinical translation of these abnormalities in attention processes is not well-defined, and commonly used neuropsychological tests are not able to detect significant deficits in Parkinson's disease patients with isolated minor hallucinations. ObjectivesTo analyze the behavioral and electrophysiological correlates of minor hallucinations in Parkinson's disease during an attentional task assessing response inhibition and interference control. MethodsFifty-five non-demented Parkinson's disease patients with (PD-mH; n = 27) and without minor hallucinations (PD-NH; n = 28) were included in the analysis. An Ericksen flanker task was performed to compare the effect of presenting congruent and incongruent stimuli on accuracy, reaction times and stimulus-locked event-related potentials morphology. ResultsAlthough both groups showed equivalent performance in a standard neuropsychological assessment, in the flanker task accuracy rates were lower in the PD-mH group in incongruent trials (p = 0.005). In the event-related potentials, PD-mH patients showed increased amplitude of the N2 at Fz [t(53); p < 0.05] and decreased amplitude of the P300 at Pz [t(53); p < 0.05] for the incongruent trials. ConclusionsParkinson's disease patients with isolated minor hallucinations were more susceptible to interference mediated by irrelevant stimuli and had less cognitive control for suppressing these interferences. The failure of these systems could precipitate the intrusion and overrepresentation of peripheral irrelevant stimuli perceived as minor hallucinations. The Ericksen flanker task could be used as a sensitive clinical marker of the attentional defects leading to hallucinations in Parkinson's disease.

Teaching Video NeuroImage: Peculiar Hobby Horse Gait in Huntington Disease-like 2.

A 59-year-old woman presented at age 48 years with abnormal hand movements, which became generalized 1 year later, along with a clumsy gait. Two years later, severe apathy and minor auditory hallucinations ensued. Her father died undiagnosed with involuntary movements at age 82 years, and 2 of her 6 sisters have also had a similar clinical picture. Neurologic examination revealed generalized chorea and an unusual dystonic gait pattern remarkably similar to the hobby horse gait, described in DYT-TUBB4A (DYT-4), which is characterized by a toe walking stiff-legged and skipping gait1 (Video 1). Walking backward improved the gait. Diagnostic workup revealed acanthocytes and mild caudate atrophy (Figure 1). A pathogenic 46 CTG/CAG repeat expansion on the JPH3 gene allowed the diagnosis of Huntington disease–like 2, an autosomal dominant Huntington disease phenocopy characterized by chorea, dystonia, and parkinsonism.2 This case expands underlying conditions recognized to cause the HHG (please see the Supplement, [links.lww.com/WNL/B931][1]). [1]: http://links.lww.com/WNL/B931

Elevation of Plasma Homocysteine and Minor Hallucinations in Parkinson's Disease: A Cross-Sectional Study.

Purpose Minor hallucinations (MHs) are the most common psychotic phenomena in Parkinson's disease (PD), and it has important clinical and prognostic implications in PD. Plasma homocysteine (Hcy) has been reported to predict the outcome of PD; whether or not Hcy is associated with MH is not known. We aim to investigate the Hcy level and related factors in patients with PD and MH. Methods We conducted a cross-sectional study and included 99 patients with PD, 34 with MH, and 65 without any hallucinations. The clinical and demographic data of the patients with and without hallucinations were compared. Hcy-related clinical factors were also analyzed. Results The plasma Hcy level was higher in MH patients than in patients without hallucinations, and the result was more pronounced in male patients than in female patients. Differences were also observed when the groups were divided on the basis of levodopa equivalent daily dose and disease duration. The high Hcy concentration was correlated with some symptoms in patients with MH, including motor dysfunction and nonmotor symptoms, such as symptoms of the gastrointestinal tract, angiocarpy, sleep/fatigue, and poor visuospatial/executive function. Conclusions Results indicated a higher plasma Hcy concentration in MH patients than in their counterparts and revealed that Hcy is associated with certain motor and nonmotor symptoms in patients with MH. Hcy may be a marker of MH and have important therapeutic implications in PD.

Visual hallucinations in Lewy body disease: pathophysiological insights from phenomenology

Visual hallucinations (VH) in Lewy body disease (LBD) have a heterogenous phenomenology classified into minor phenomena (MVH) and complex hallucinations (CVH). Mechanisms underpinning VH and their temporal aspects are largely unknown. According to the hodotopic model, we investigated whether changes in distinct cognitive domains and neural networks in the hallucination trait underpin temporal aspects of MVH and CVH in the hallucination state. 35 LBD patients with VH underwent a complete neuropsychological evaluation and resting-state fMRI. North-East-Visual-Hallucinations-Interview was used to assess their typical VH content, duration, and frequency. We found that MVH was not associated with cognitive impairment, while CVH was associated with impairments in visuoperceptual processes, attention and visual abstract reasoning. In seed-to-seed functional connectivity (FC) analysis we identified functional couplings associated with MVH and CVH temporal severity (duration x frequency), duration and frequency. MVH severity was negatively associated with FC between early visual areas (EVA) and ventral-visual-stream regions, and negatively associated with FC between brainstem and EVA, which may be linked to LBD brainstem neuropathology. CVH duration was positively associated with FC between ventral-visual stream and salience network (SN). CVH frequency was negatively associated with FC between DMN and SN. Functional alterations in distinct visual and attentional networks and their dynamic interaction in trait LBD hallucinators are linked to both the phenomenology of state content and its temporal characteristics. Within a network, VH frequency and duration may be linked to different types of functional alterations: increased connectivity leading to sustained activity prolonging VH (duration) and decreased connectivity increasing dysregulated, spontaneous activity (frequency). These findings support the hodotopic hypothesis of VH and may reflect a link between VH phenomenology, LBD neuropathological progression and the involvement of specific neurotransmitter systems.

Clinical Characteristics of Minor Hallucinations in Chinese Parkinson's Disease Patients.

BackgroundPsychotic symptoms are common in Parkinson's disease (PD). However, the clinical characteristics of PD psychosis (PDP) have been rarely reported in Chinese PD patients. We aimed to categorize PDP in a PD cohort and its relationship to other clinical characteristics.MethodsA total of 149 Chinese PD patients were consecutively enrolled, and idiopathic PD patients were recruited in the study. The symptoms of PDP were assessed with the enhanced Scale for the Assessment of Positive Symptoms in PD. Then, the patients were classified into a PD-control group, isolated minor hallucination (MH) group, and complex MH group, and clinical and demographic data of different groups were compared.ResultsParkinson's disease psychosis was present in 40.3% (60/149) of our patients. The most common PDPs were MHs, present in 32.9% (49 of 149) of the cohort. Compared to patients without MHs, patients with MHs were older, had a longer disease duration, a higher levodopa equivalent daily dose, more severe motor symptoms, dyskinesia, a higher rate of rapid eye movement sleep behavior disorders, frontal lobe function impairments, and a higher percentage of cognitive impairment. Logistic regression analysis showed that advanced Hoehn-Yahr stage [odds ratio (OR): 2.697, p = 0.007)] and frontal lobe function impairment (OR: 0.684, p = 0.003) were independent risk factors for MHs.ConclusionMHs were frequent non-motor symptoms in PD patients. It was associated with increased motor and non-motor symptom burdens and reduced quality of life. MHs have been called “minor,” but they have major clinical and prognostic implications and need early screening.

Minor hallucinations in isolated rapid eye movement sleep behavior disorder indicative of early phenoconversion: A preliminary study.

Minor hallucinations (MH) are psychotic symptoms that can occur anywhere between prodromal to early Parkinson's disease and after onset of motor problems. MH include visual illusions, presence hallucinations, and passage hallucinations. Isolated rapid eye movement sleep behavior disorder (RBD) is a harbinger of neurodegenerative diseases. We conducted a retrospective cohort study to investigate the clinical characteristics of isolated RBD with MH and the risk of phenoconversion. We retrospectively analyzed the data of 36 patients with isolated RBD (four females; median age, 75.0years). We defined cases reporting at least one minor hallucination as RBD with MH. Demographic data and cognitive function were compared between patients with and without MH, and Cox proportional hazards models estimated the risk of phenoconversion. We included 10 (27.8%) patients with MH and 26 (72.2%) without MH. Patients with MH were older, had less dopamine transporter accumulation, more severe autonomic dysfunction, more depressive symptoms, and lower verbal fluency and symbol coding test scores than patients without MH. After follow-up (median, 2.50years), 13.9% (5/36) of all patients developed phenoconversion (Parkinson's disease, two patients; dementia with Lewy bodies, three patients). The rate of phenoconversion was significantly higher in patients with MH (40.0% vs. 3.8%, p=.005). The Cox proportional hazards model adjusted for age, sex, and disease duration revealed that MH was a significant risk factor for phenoconversion (hazard ratio, 14.72; 95% confidence interval, 1.35-160.5). Minor hallucinations may be utilized as early clinical markers for prodromal estimation of neurodegenerative diseases.

Prevalence and Risk Factors for Minor Hallucinations in Patients with Parkinson's Disease.

Purpose As the most frequent and earliest type of psychotic phenomenon in Parkinson's disease (PD), minor hallucination (MH) can occur before the onset of motor symptoms. This sensation may be an early predictor of severe psychotic and cognitive states and is often overlooked in clinics. This study was aimed at providing a comprehensive and in-depth understanding of MHs. Patients and Methods. Demographic information was obtained from 262 patients with PD, and a series of clinical assessment questionnaires were provided. According to the result of the Movement Disorders Society Unified Parkinson's Disease Rating Scale Part I, the patients were classified into the MH and nonhallucination (NH) groups. Results MHs were the most common psychotic symptom with 38.9% prevalence. The most frequent MH was visual illusion, especially object misidentification. Three minor phenomena were somewhat consistent in terms of external factors, temporal factors, and content. Disease duration, daily levodopa equivalent dose, and percentage of levodopa and dopamine-receptor agonist use were remarkably greater in the MH group than in the NH group. After covariate control, the MH group had worse life quality and more severe nonmotor symptoms, including poor sleep quality and rapid eye movement sleep behavior disorder (RBD), than the NH group. The binary logistic regression model showed that RBD, sleep quality, and health-related life quality were associated with MHs. Conclusion A high prevalence of MHs was observed in patients with PD. Further studies are needed to confirm and expand the identified clinical factors related to MH, which have potential prognostic and therapeutic implication.