Test the Best: Classification Accuracies of Four Cognitive Rating Scales for Parkinson's Disease Mild Cognitive Impairment

Preoperative cognitive profile predictive of cognitive decline after subthalamic deep brain stimulation in Parkinson's disease

Cognitive decline represents a severe non-motor symptom of Parkinson's disease (PD) that can significantly reduce the benefits of subthalamic deep brain stimulation (STN DBS). Here, we aimed to describe post-surgery cognitive decline and identify pre-surgery cognitive profile associated with faster decline in STN DBS-treated PD patients. A retrospective observational study of 126 PD patients treated by STN DBS combined with oral dopaminergic therapy followed for 3.54 years on average (SD = 2.32) with repeated assessments of cognition was conducted. Pre-surgery cognitive profile was obtained via a comprehensive neuropsychological examination and data analysed using exploratory factor analysis and Bayesian generalized linear mixed models. On the whole, we observed a mild annual cognitive decline of 0.90 points from a total of 144 points in the Mattis Dementia Rating Scale (95% posterior probability interval [-1.19, -0.62]) with high inter-individual variability. However, true score changes did not reach previously reported reliable change cut-offs. Executive deficit was the only pre-surgery cognitive variable to reliably predict the rate of post-surgery cognitive decline. On the other hand, exploratory analysis of electrode localization did not yield any statistically clear results. Overall, our data and models imply mild gradual average annual post-surgery cognitive decline with high inter-individual variability in STN DBS-treated PD patients. Nonetheless, patients with worse long-term cognitive prognosis can be reliably identified via pre-surgery examination of executive functions. To further increase the utility of our results, we demonstrate how our models can help with disentangling true score changes from measurement error in future studies of post-surgery cognitive changes.

Efficacy and safety of acupuncture therapy for neuropsychiatric symptoms among patients with Parkinson's disease: A systematic review and meta-analysis

OBJECTIVE

To systematically evaluate the efficacy and safety of acupuncture therapy for neuropsychiatric symptoms in patients with Parkinson's disease.

METHODS

We searched eight databases from their inception until 14 April 2024, including PubMed, Cochrane Library, Embase, Web of Science, SinoMed, China National Knowledge Infrastructure, China Science and Technology Periodical Database, and Wanfang Database. The search aimed to find randomized controlled trials assessing the effectiveness of acupuncture for neuropsychiatric symptoms in patients with Parkinson's disease. Literature screening and data extraction were performed independently by the authors. Meta-analysis was conducted using RevMan V.5.3 software, and Stata 17.0 software was used for detecting publication bias and performing sensitivity analysis.

RESULTS

Twenty-eight studies, involving 2148 participants, met the inclusion criteria. The meta-analysis revealed that acupuncture therapy improved depression-related scale scores (standardized mean difference (SMD) = -0.70, 95%CI [-0.98, -0.42], p < 0.00001), anxiety-related scale scores (SMD = -0.78, 95% CI [-1.43, -0.14], p = 0.02), Montreal Cognitive Assessment scores (weighted mean difference (WMD) = 2.74, 95% CI [2.43, 3.05], p < 0.00001), Mini Mental State Examination scores (WMD = 2.36, 95% CI [0.78, 3.94], p = 0.003), Yale-Brown Obsessive Compulsive Scale scores, and Parkinson's Disease Questionnaire-39 scores (WMD = -2.66, 95% CI [-4.83, -0.49], p = 0.02) compared to controls.

CONCLUSION

This review supports the application of acupuncture to reduce the severity of neuropsychiatric symptoms including depression, anxiety, and impulse control disorders, and to improve cognition and quality of life in patients with Parkinson's disease. The adverse effects associated with acupuncture, either alone or as adjunctive therapy, were relatively minor.

Does the Montreal Cognitive Assessment (MoCA) identify cognitive impairment profiles in Parkinson's disease? An exploratory study

An important proportion of patients with Parkinson's Disease (PD) present signs of cognitive impairment, although this is heterogeneous. In an attempt to classify this, the dual syndrome hypothesis distinguishes between two profiles: one defined by attentional and executive problems with damage in anterior cerebral regions, and another with mnesic and visuospatial alterations, with damage in posterior cerebral regions. The Montreal Cognitive Assessment (MoCA) is one of the recommended screening tools, and one of the most used, to assess cognitive impairment in PD. However, its ability to specifically identify these two profiles of cognitive impairment has not been studied. The aim of this study was, therefore, to analyze the capacity of the MoCA to detect cognitive impairment, and also to identify anterior and posterior profiles defined by the dual syndrome hypothesis. For this purpose, 59 patients with idiopathic PD were studied with the MoCA and a neuropsychological battery of tests covering all cognitive domains. Results of logistic regression analysis with ROC (Receiver Operating Characteristic) curves showed that MoCA detected cognitive impairment and identified patients with a profile of anterior/attentional and executive deficit, with acceptable sensibility and specificity. However, it did not identify patients with a posterior/mnesic-visuospatial impairment. We discuss the reasons for the lack of sensitivity of MoCA in this profile, and other possible implications of these results with regards the usefulness of this tool to assess cognitive impairment in PD.

Changes in miR-134-3p expression and zDHHC3-AMPARs axis in association with aluminum neurotoxicity

Aluminum (Al) is a neurotoxic substance associated with cognitive dysfunction and neurodegenerative diseases, such as Alzheimer's disease, but the mechanisms for aluminum neurotoxicity remain to be identified. In this work, we try to investigate a novel potential biomarker of cognitive dysfunction following aluminum exposure and the mechanism involved. Recently, miR-134-3p was reported as a novel regulator of cognitive function. To address this, we investigate the expression level of miR-134-3p in plasma from 280 aluminum factory workers and analyzed the correlation between miRNA-134-3p, blood Al concentration, and Montreal Cognitive Assessment Scale (MoCA scale) score. The results implied that occupational aluminum exposure elevated miR-134-3p expression in the plasma of workers accompanied by cognitive impairment. Our experiment studies using both animal models and PC12 cells validated the upregulation of miR-134-3p caused by aluminum. In addition, we identified that palmitoylation enzyme zDHHC3 was the target of miR-134-3p, and the decreasing AMPAR receptor (AMPAR) trafficking was related to the learning and memory impairment induced by aluminum. More importantly, using transfection and interference approaches in PC12 cells, inhibition of miR-134-3p resulted in a recovery of zDHHC3-AMPARs axis to a certain extent in response to aluminum. In summary, miR-134-3p was found to be involved in aluminum neurotoxicity by targeting zDHHC3-AMPARs axis and could serve as a potential biomarker or helpful target.

Multi-Disease Validation of the RUDAS for Cognitive Screening in Alzheimer's Disease, Parkinson's Disease, and Multiple Sclerosis

BACKGROUND

The Rowland Universal Dementia Assessment Scale (RUDAS) is a cognitive test with favorable diagnostic properties for detecting dementia and a low influence of education and cultural biases.

OBJECTIVE

We aimed to validate the RUDAS in people with Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS).

METHODS

We enrolled one hundred and fifty participants (60 with AD, 30 with PD, 60 with MS, and 120 healthy controls (HC)). All clinical groups completed a comprehensive neuropsychological battery, RUDAS, and standard cognitive tests of each disorder: MMSE, SCOPA-COG, and Symbol Digit Modalities Test. Intergroup comparisons between clinical groups and HC and ROC curves were estimated. Random Forest algorithms were trained and validated to detect cognitive impairment using RUDAS and rank the most relevant scores.

RESULTS

The RUDAS scores were lower in patients with AD, and patients with PD and MS showed cognitive impairment compared to healthy controls. Effect sizes were generally large. The total score was the most discriminative, followed by the memory score. Correlations with standardized neuropsychological tests were moderate to high. Random Forest algorithms obtained accuracies over 80-90% using the RUDAS for diagnosing AD and cognitive impairment associated with PD and MS.

CONCLUSION

Our results suggest the RUDAS is a valid test candidate for multi-disease cognitive screening tool in AD, PD, and MS.

Social decision-making in Parkinson's disease

INTRODUCTION

Parkinson's Disease (PD) commonly affects cognition and communicative functions, including the ability to perceive socially meaningful cues from nonverbal behavior and spoken language (e.g., a speaker's tone of voice). However, we know little about how people with PD use social information to make decisions in daily interactions (e.g., decisions to trust another person) and whether this ability rests on intact cognitive functions and executive/decision-making abilities in nonsocial domains.

METHOD

Non-demented adults with and without PD were presented utterances that conveyed differences in speaker confidence or politeness based on the way that speakers formulated their statement and their tone of voice. Participants had to use these speech-related cues to make trust-related decisions about interaction partners while playing the Trust Game. Explicit measures of social perception, nonsocial decision-making, and related cognitive abilities were collected.

RESULTS

Individuals with PD displayed significant differences from control participants in social decision-making; for example, they showed greater trust in game partners whose voice sounded confident and who explicitly stated that they would cooperate with the participant. The PD patients displayed relative intact social perception (speaker confidence or politeness ratings) and were unimpaired on a nonsocial decision-making task (the Dice game). No obvious relationship emerged between measures of social perception, social decision-making, or cognitive functioning in the PD sample.

CONCLUSIONS

Results provide evidence of alterations in decision-making restricted to social contexts in PD individuals with relatively preserved cognition with minimal changes in social perception. Researchers and practitioners interested in how PD affects social perception and cognition should include assessments that emulate social interactions, as non-interactive tasks may fail to detect the full impact of the disease on those affected.

Linguistic Abnormalities in Isolated Rapid Eye Movement Sleep Behavior Disorder

BACKGROUND

Patients with synucleinopathies frequently display language abnormalities. However, whether patients with isolated rapid eye movement sleep behavior disorder (iRBD) have prodromal language impairment remains unknown.

OBJECTIVE

We examined whether the linguistic abnormalities in iRBD can serve as potential biomarkers for conversion to synucleinopathy, including the possible effect of mild cognitive impairment (MCI), speaking task, and automation of analysis procedure.

METHODS

We enrolled 139 Czech native participants, including 40 iRBD without MCI and 14 iRBD with MCI, compared with 40 PD without MCI, 15 PD with MCI, and 30 healthy control subjects. Spontaneous discourse and story-tale narrative were transcribed and linguistically annotated. A quantitative analysis was performed computing three linguistic features. Human annotations were compared with fully automated annotations.

RESULTS

Compared with control subjects, patients with iRBD showed poorer content density, reflecting the reduction of content words and modifiers. Both PD and iRBD subgroups with MCI manifested less occurrence of unique words and a higher number of n-grams repetitions, indicating poorer lexical richness. The spontaneous discourse task demonstrated language impairment in iRBD without MCI with an area under the curve of 0.72, while the story-tale narrative task better reflected the presence of MCI, discriminating both PD and iRBD subgroups with MCI from control subjects with an area under the curve of up to 0.81. A strong correlation between manually and automatically computed results was achieved.

CONCLUSIONS

Linguistic features might provide a reliable automated method for detecting cognitive decline caused by prodromal neurodegeneration in subjects with iRBD, providing critical outcomes for future therapeutic trials. © 2022 International Parkinson and Movement Disorder Society.

A New Instrument Combines Cognitive and Social Functioning Items for Detecting Mild Cognitive Impairment and Dementia in Parkinson’s Disease

Background

The commonly used screening tests for Parkinson’s disease (PD) are the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE), both of which only focus on cognitive function. A composite assessment that considers both cognitive and social dysfunction in PD would be helpful in detecting mild cognitive impairment (MCI) and PD dementia (PDD).

Objective

We aimed to simplify the commonly used tools and combine cognitive and social functioning tests to detect early MCI and PDD.

Materials and Methods

A total of 166 participants (84 PD patients and 82 healthy) were recruited who completed the MMSE, MoCA, PD social functioning scale (PDSFS), clock drawing test, activities of daily living, comprehensive neuropsychological assessment (e.g., executive, attention, language, memory, and visuospatial functions), and movement disorder society (MDS)-unified PD rating scale. According to the MDS diagnostic criteria, the patients were grouped into PD-nonMCI, PD-MCI, or PDD.

Results

To detect PD-MCI, the optimal cut-off scores for the simplified MoCA and the combined test were 9 and 35. The discrimination values measured by the area under the receiver operating characteristic curve (AUC) of the two tests were 0.767 (p < 0.001) and 0.790 (p < 0.001). When the simplified MoCA was 7 or the combined test 30, the patients would be classified as having PDD. The AUCs of the two tests were 0.846 (p < 0.001) and 0.794 (p = 0.003).

Conclusion

We suggest considering both cognitive and social functions when detecting PD-MCI and PDD.

Distinct patterns of speech disorder in early-onset and late-onset de-novo Parkinson's disease

Substantial variability and severity of dysarthric patterns across Parkinson's disease (PD) patients may reflect distinct phenotypic differences. We aimed to compare patterns of speech disorder in early-onset PD (EOPD) and late-onset PD (LOPD) in drug-naive patients at early stages of disease. Speech samples were acquired from a total of 96 participants, including two subgroups of 24 de-novo PD patients and two subgroups of 24 age- and sex-matched young and old healthy controls. The EOPD group included patients with age at onset below 51 (mean 42.6, standard deviation 6.1) years and LOPD group patients with age at onset above 69 (mean 73.9, standard deviation 3.0) years. Quantitative acoustic vocal assessment of 10 unique speech dimensions related to respiration, phonation, articulation, prosody, and speech timing was performed. Despite similar perceptual dysarthria severity in both PD subgroups, EOPD showed weaker inspirations (p = 0.03), while LOPD was characterized by decreased voice quality (p = 0.02) and imprecise consonant articulation (p = 0.03). In addition, age-independent occurrence of monopitch (p < 0.001), monoloudness (p = 0.008), and articulatory decay (p = 0.04) was observed in both PD subgroups. The worsening of consonant articulation was correlated with the severity of axial gait symptoms (r = 0.38, p = 0.008). Speech abnormalities in EOPD and LOPD share common features but also show phenotype-specific characteristics, likely reflecting the influence of aging on the process of neurodegeneration. The distinct pattern of imprecise consonant articulation can be interpreted as an axial motor symptom of PD.

Improvements in clinical signs of Parkinson's disease using photobiomodulation: a prospective proof-of-concept study

Background

Parkinson’s disease (PD) is a progressive neurodegenerative disease with no cure and few treatment options. Its incidence is increasing due to aging populations, longer disease duration and potentially as a COVID-19 sequela. Photobiomodulation (PBM) has been successfully used in animal models to reduce the signs of PD and to protect dopaminergic neurons.

Objective

To assess the effectiveness of PBM to mitigate clinical signs of PD in a prospective proof-of-concept study, using a combination of transcranial and remote treatment, in order to inform on best practice for a larger randomized placebo-controlled trial (RCT).

Methods

Twelve participants with idiopathic PD were recruited. Six were randomly chosen to begin 12 weeks of transcranial, intranasal, neck and abdominal PBM. The remaining 6 were waitlisted for 14 weeks before commencing the same treatment. After the 12-week treatment period, all participants were supplied with PBM devices to continue home treatment. Participants were assessed for mobility, fine motor skills, balance and cognition before treatment began, after 4 weeks of treatment, after 12 weeks of treatment and the end of the home treatment period. A Wilcoxon Signed Ranks test was used to assess treatment effectiveness at a significance level of 5%.

Results

Measures of mobility, cognition, dynamic balance and fine motor skill were significantly improved (p < 0.05) with PBM treatment for 12 weeks and up to one year. Many individual improvements were above the minimal clinically important difference, the threshold judged to be meaningful for participants. Individual improvements varied but many continued for up to one year with sustained home treatment. There was a demonstrable Hawthorne Effect that was below the treatment effect. No side effects of the treatment were observed.

Conclusions

PBM was shown to be a safe and potentially effective treatment for a range of clinical signs and symptoms of PD. Improvements were maintained for as long as treatment continued, for up to one year in a neurodegenerative disease where decline is typically expected. Home treatment of PD by the person themselves or with the help of a carer might be an effective therapy option. The results of this study indicate that a large RCT is warranted.

Trial registration

Australian New Zealand Clinical Trials Registry, registration number: ACTRN12618000038291p, registered on 12/01/2018.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-021-02248-y.

Face pareidolia is associated with right striatal dysfunction in drug-naïve patients with Parkinson's disease

BACKGROUND AND AIM

Some patients with Parkinson's disease (PD) present with pareidolia, an illusion of a meaningless stimulus as a familiar object known to the observer. Since the striatum is associated with processing of visual information, we investigated correlations of pareidolia with motor symptoms and striatal dopaminergic function.

METHOD

A noise pareidolia test, assessment of motor symptoms using MDS-UPDRS and ¹²³I-Ioflupane SPECT were performed in 58 drug-naïve PD patients. A number of images in which a participant noticed an illusory face (number of illusory responses) were compared with motor assessment scores and uptake of ¹²³I-ioflupane in the striatum.

RESULTS

Of the 58 participants, 22 had at least one illusory response. Mean scores for MDS-UPDRS part III (p<0.05), rigidity (p<0.05), and rigidity on the left side of the body (p<0.01) in patients with pareidolia were significantly higher than those in patients without pareidolia. Uptake of ¹²³I-ioflupane in the right caudate nucleus (p<0.05), anterior putamen (p<0.01), and posterior putamen (p<0.01) in patients with pareidolia was significantly lower than in patients without pareidolia. In the 22 patients with pareidolia, the number of illusory responses was significantly correlated with total scores for MDS-UPDRS part III (r=0.443, p<0.05) and subscores for bradykinesia (r=0.440, p<0.05) and bradykinesia on the left side of the body (r=0.564, p<0.01). The prevalence of pareidolia in left-dominant parkinsonism (16/30 patients) was higher than that in right-dominant parkinsonism (6/28 patients) (p<0.05 by chi-square test).

CONCLUSION

Pareidolia in PD patients is associated with dysfunction in the right striatum.