The MoCA: well-suited screen for cognitive impairment in Parkinson disease

Correlation between plasma epidermal growth factor and follow-up cognitive decline in Parkinson's disease

BACKGROUND

Epidermal growth factor (EGF) has been shown to have neuroprotective effects in Parkinson's disease (PD). However, there is a lack of research on the association between plasma EGF levels and cognitive impairments in PD patients.

METHODS

The study included 135 PD patients. Plasma EGF concentrations were measured. PD patients without cognitive impairment were followed up for clinical assessment at an average of 2 ± 0.6 years.

RESULTS

PD patients with cognitive impairment (PD-CI) had lower baseline plasma EGF concentrations compared to PD patients without cognitive impairment. Linear regression analysis demonstrated a significant correlation between baseline plasma EGF concentrations and baseline Montreal Cognitive Assessment (MoCA) and Digit Symbol Substitution Test (DSST) scores in PD patients. However, no significant association was found between plasma EGF concentrations and Hopkins Verbal Learning Test-Delayed Recall (HVLT-DR), Semantic Fluency Test (SFT), Clock Drawing Test (CDT), Trail Making Test (TMT) A, or TMT B scores. Furthermore, logistic regression analysis revealed that baseline plasma EGF concentrations were associated with cognitive decline in PD patients without cognitive impairment in adjusted regression models (HR 0.977, 95% CI 0.955-0.999, p = 0.045), after adjusting for various factors. The area under the curve (AUC) for cognitive decline at follow-up time was 0.704 (95% CI 0.600-0.809), and the optimal cut-point for baseline plasma EGF concentrations was determined to be 49.56 pg/mL, with a sensitivity of 49.3% and specificity of 92.3%.

CONCLUSIONS

In conclusion, our study found a correlation between baseline plasma EGF concentrations and cognitive dysfunction in PD.

One-year practice effects predict long-term cognitive outcomes in Parkinson's disease

Background: Predicting which individuals with Parkinson's disease (PD) will develop cognitive deficits is challenging, but important towards selecting those individuals at higher risk of progression for personalized early intervention and enriching samples for clinical trials of disease modifying agents. Objective: To examine whether practice effects on cognitive tests across one-year are predictive of eventual cognitive impairment (CI) and dementia (PDD) in individuals with PD. Methods: Individuals with PD (n = 549) from the PPMI database who were cognitively intact at baseline were included for analysis. The Montreal Cognitive Assessment (MoCA) was administered at baseline and during annual follow-up visits over at least five years to determine if participants remained intact (MoCA ≥ 26) or developed CI (MoCA ≤ 25) or dementia (MoCA ≤ 21). Participants also completed a neuropsychological battery at baseline and again after a one-year interval. Practice effects on the cognitive tests across one-year were quantified with standardized regression-based change scores using PPMI data from cognitively intact subjects without PD. Results: Based on MoCA scores, 39% of patients developed CI and 10% developed PDD during the study. Linear regressions revealed smaller practice effects across one year in people with PD than in controls. Within the PD group, Cox regression analyses showed that smaller practice effects on tests of various cognitive domains were associated with an increased risk for CI. For PDD, only practice effects on a measure of processing speed significantly predicted cognitive outcomes. Conclusions: These findings demonstrate that practice effects have prognostic value in long-term cognitive outcomes in PD. This has important implications for clinical care and research, as one-year practice effects could help identify individuals at risk for CI and PDD and enrich samples for future clinical trials. Limitations of the present study pertain to the classification of cognitive impairment on the basis of a screening instrument (i.e., the MoCA) without evidence of the absence/presence of functional impairment, and the clinical utility of the one-year interval.

Validation of the International Parkinson and Movement Disorder Society Non-Motor Symptoms Questionnaire (MDS-NMS-Q)

BACKGROUND

The Movement Disorder Society Non-Motor Rating Scale (MDS-NMS) assesses severity and frequency of non-motor symptoms (NMS) in Parkinson's disease (PD) and is rater-administered. The MDS-NMS Questionnaire (MDS-NMS-Q), developed as a briefer (i.e., assessing symptom severity only), self-completed version of the MDS-NMS, is also a 13-domain, 52-symptom instrument with a separate non-motor fluctuations (NMFs) section.

OBJECTIVE

The goal was to validate the MDS-NMS-Q versus the MDS-NMS.

METHODS

A cross-sectional, multi-site, international study was conducted with idiopathic PD patients. After completing the self-administered MDS-NMS-Q unsupervised, patients were assessed with the rater-administered MDS-NMS.

RESULTS

The cohort consisted of 199 PD patients (mean age [±standard deviation (SD)] = 67.19 [±9.95] years; mean age at PD diagnosis [±SD] = 59.27 [±9.54] years); median Hoehn and Yahr stage = 2. Data quality was satisfactory for all 13 MDS-NMS-Q domains. There were no floor or ceiling effects for the total score; individual domains had no appreciable ceiling effects, but variable floor effects (5.0%-71.4%). Internal consistency for most domains was satisfactory, except for the impulse control domain (Cronbach's α ≥0.75 for 10/13 domains). Correlation and concordance between MDS-NMS-Q and MDS-NMS total scores were high (Spearman rank correlation coefficient = 0.86; Kendall's coefficient of concordance = 0.93).

CONCLUSIONS

The MDS-NMS-Q has a strong association and concordance with the MDS-NMS at the total score and domain level. This indicates that the MDS-NMS-Q, allowing self-completion and focusing only on symptom severity, is an acceptable alternative to rater administration assessing both severity and frequency. © 2025 International Parkinson and Movement Disorder Society.

Neuroimaging-based data-driven subtypes of spatiotemporal atrophy due to Parkinson's disease

Parkinson's disease is the second most common neurodegenerative disease. Despite this, there are no robust biomarkers to predict progression, and understanding of disease mechanisms is limited. We used the Subtype and Stage Inference algorithm to characterize Parkinson's disease heterogeneity in terms of spatiotemporal subtypes of macroscopic atrophy detectable on T1-weighted MRI-a successful approach used in other neurodegenerative diseases. We trained the model on covariate-adjusted cortical thicknesses and subcortical volumes from the largest known T1-weighted MRI dataset in Parkinson's disease, Enhancing Neuroimaging through Meta-Analysis consortium Parkinson's Disease dataset (n = 1100 cases). We tested the model by analyzing clinical progression over up to 9 years in openly-available data from people with Parkinson's disease from the Parkinson's Progression Markers Initiative (n = 584 cases). Under cross-validation, our analysis supported three spatiotemporal atrophy subtypes, named for the location of the earliest affected regions as: 'Subcortical' (n = 359, 33%), 'Limbic' (n = 237, 22%) and 'Cortical' (n = 187, 17%). A fourth subgroup having sub-threshold/no atrophy was named 'Sub-threshold atrophy' (n = 317, 29%). Statistical differences in clinical scores existed between the no-atrophy subgroup and the atrophy subtypes, but not among the atrophy subtypes. This suggests that the prime T1-weighted MRI delineator of clinical differences in Parkinson's disease is atrophy severity, rather than atrophy location. Future work on unravelling the biological and clinical heterogeneity of Parkinson's disease should leverage more sensitive neuroimaging modalities and multimodal data.

What does it mean when the pleasant smells come and go? Correlation between UPSIT odor identification status and fluctuation of non-motor symptoms in Parkinson's disease

Parkinson's disease (PD) is characterized by motor and non-motor symptoms, including olfactory dysfunction. Prior studies have shown that olfaction deteriorates with disease progression, however fluctuations in olfaction and related PD symptoms have been less explored. This study aimed to investigate correlations between changes in odor identification ability and PD symptoms. PD patients recruited from Taichung Veterans General Hospital underwent at least two consecutive Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) and University of Pennsylvania Smell Identification Test (UPSIT) evaluations. The patients were grouped based on changes in olfactory identification ability between evaluations, and fluctuations in PD symptoms were compared between groups. Ninety-seven PD patients with 114 complete sets of data were analyzed. Significant divergent results were observed between changes in five MDS-UPDRS non-motor subscores and the conversion status of five pleasant odors, including anxiety vs. bubble gum, apathy vs. banana, dizziness vs. coconut, urination vs. root beer, and dopamine dysregulation syndrome (DDS) vs. grape. Fluctuations in the ability to detect pleasant odors, may have a complex interaction with other non-motor symptoms, including in the neurobehavioral and autonomic domains. Serial monitoring of olfactory function, particularly with pleasant odors, may provide valuable insights for tracking non-motor symptoms in PD and warrants further investigation into their therapeutic implications.

Rigidity in Parkinson's Disease: The Objective Effect of Levodopa

BACKGROUND

Quantitative evidence of levodopa-induced beneficial effects on parkinsonian rigidity in Parkinson's disease (PD) is lacking. Recent research has demonstrated the velocity-dependent nature of objective rigidity in PD and revealed its neural underpinning.

OBJECTIVE

The present study aimed to examine the effect of levodopa on objective rigidity in PD.

METHODS

Eighteen patients with PD underwent clinical and instrumental evaluations of muscle tone in the OFF and ON states. The clinical assessments focused on rigidity in the most affected upper limb. The biomechanical components of objective rigidity were assessed using robot-assisted wrist extensions at seven angular velocities (5-280°/s). Surface electromyography of the flexor carpi radialis muscle enabled the concurrent evaluation of short- and long-latency stretch reflexes (SLR and LLR).

RESULTS

Levodopa improved the clinical scores of rigidity. Biomechanical measurements showed that levodopa reduced the total and neural components of force but had no effect on viscoelastic components. Levodopa reduced the velocity dependence of the LLRs but did not affect the SLRs. Finally, we found significant clinical-instrumental correlations between levodopa-induced changes and biomechanical and neurophysiological measures of objective rigidity in PD.

CONCLUSIONS

Levodopa improved objective rigidity in PD by decreasing its biomechanical neural component as well as the size of LLRs. The beneficial effect of levodopa on biomechanical and neurophysiological features of objective rigidity was related to the specific angular velocity of wrist extensions; that is, the higher the angular velocity, the greater the beneficial impact of levodopa on objective rigidity. These findings allowed the description of a new pathophysiological model of rigidity in PD. © 2025 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Pushing the limit to reach meaningful change: the impact of intensity-driven exercise on clinical outcomes for individuals with Parkinson's disease. A single-subject design

PURPOSE

Parkinson's disease creates an inability to perform previous learned autonomic tasks, such as walking, which worsens with disease progression. Recommendations to incorporate exercise at moderate to high intensities for this population has been established but there is limited knowledge about its impact on clinical based outcomes. The purpose of this research is to investigate the effectiveness of a 6-week intensity-driven walking program on clinical-based outcomes in individuals with PD.

MATERIALS/METHODS

Five individuals with PD were recruited for this single-subject withdrawal design (A-B-A-B) study. 6-minute walk performance and other core neurological measures of gait were collected. Intervention phases incorporated a 30-minute individualized intensity-driven treadmill walking program practiced at 65% or more of ones maximum heart rate. Increased treadmill speed, incline, and resistance were manipulated to reach the target heart rate zone.

RESULTS

6-minute walk test within condition visual analysis demonstrated a therapeutic change during intervention phases and a countertherapeutic change during withdraw periods for all 5 individuals. An abrupt therapeutic effect was demonstrated for all individuals between conditions with the percent of nonoverlapping data ranging from 70-90%. Band method analysis revealed a range of 9-19 sessions two standard deviations above baseline mean performances for all individuals.

CONCLUSION

To achieve sufficient walking performance, gait practiced at higher intensity levels may provide the optimal solution as an adjunct to standard care for individuals with PD who want to improve their walking.

Repetitive transcranial magnetic stimulation elevates the serum levels of neurotrophic factors and serotonin and its metabolites in patients with ischemic stroke

Objective

Repetitive transcranial magnetic stimulation (rTMS) can effectively treat cognitive impairment in stroke patients; however, its mechanism of action remains unclear. The aim of this study was to investigate whether rTMS improves cognitive function by regulating the levels of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), 5-hydroxytryptamine (5-HT), and 5-hydroxyindoleacetic acid (5-HIAA).

Methods

In a 4-week study, 70 patients with ischemic stroke were randomly assigned to two groups: one received rTMS (n = 35) and the other received sham-stimulation (n = 35) in addition to conventional medication and rehabilitation training. Patients in the rTMS group were treated with rTMS at 10 Hz for 20 min per session. The Montreal Cognitive Assessment (MoCA) and response time in the n-back task were used to assess the severity of the disease. Fasting venous blood was collected in the early morning, both before and after the treatment. The peripheral blood levels of BDNF, NGF, 5-HT, and 5-HIAA were measured using the enzyme-linked immunosorbent assay (ELISA).

Results

The levels of BDNF and NGF were higher in the rTMS group than in the sham group (p = 0.017, p = 0.008), after the rTMS treatment, and the levels of 5-HT and 5-HIAA were also elevated in the rTMS group (p = 0.049, p = 0.004). The changes in serum 5-HT and 5-HIAA levels after the rTMS treatment correlated with the changes in the MoCA and response time in the n-back task. There was a positive correlation between the serum 5-HT and BDNF levels (r = 0.4034).

Conclusion

Our results showed that the BDNF, NGF, 5-HT, and 5-HIAA levels were upregulated after the rTMS treatment, which likely contributed to improvements in cognitive function and quality of life in the patients with stroke.

Clinical trial registration

https://www.chictr.org.cn/showproj.html?proj=216761, ChiCTR2400082383.

Investigation of Listening Effort in Tinnitus Patients by Providing Similar Peripheral Auditory Function With Control Group

INTRODUCTION

Previous studies have investigated listening effort in tinnitus patients compared to healthy individuals. These studies reported similar pure tone hearing thresholds between groups but did not investigate possible peripheral auditory dysfunction, which could affect the central auditory system and increase listening effort even when hearing thresholds are within the normal hearing range. This study aimed to investigate the presence of listening effort in tinnitus patients by controlling for peripheral auditory function (PAF).

METHODS

This study included 16 chronic tinnitus patients and 23 matched healthy controls, both with normal hearing thresholds. The subjects were assessed using 0.125-20 kHz pure-tone audiometry, a visual analogue scale (VAS), the Montreal Cognitive Assessment (MoCA), the Tinnitus Handicap Inventory (THI), the matrix test, auditory brainstem response (ABR), and electroencephalography (EEG). EEG alpha band activity was recorded from parietal electrodes (P3, P4, Pz).

RESULTS

The increase in alpha band power during the encoding phase of sentence presentation in tinnitus patients was less than that in the control group. We found higher VAS scores in tinnitus participants. We did not find significant differences in matrix test scores, ABR amplitude, or absolute latency values between groups. The EEG alpha power change and THI did not show a significant correlation.

CONCLUSION

To the best of our knowledge, this is the first study to investigate the listening effort of tinnitus patients and healthy controls using EEG alpha band power while controlling for hearing and PAF. Tinnitus patients may expend more listening-related effort despite having similar PAF to the control group.

A Short Cognitive and Neuropsychiatric Assessment Scale for Progressive Supranuclear Palsy

BACKGROUND

Patients with Progressive Supranuclear Palsy (PSP) suffer from several neuropsychological impairments. These mainly affect the frontal lobe and subcortical brain structures. However, a scale for the assessment of cognitive and neuropsychiatric disability in PSP is still missing.

OBJECTIVES

To create and validate a new scale for cognitive and neuropsychiatric impairment in PSP.

METHODS

The Short Cognitive and Neuropsychiatric (ShoCo) scale was developed containing five items (bradyphrenia, apathy, aphasia, dysexecution and disinhibition). Each item can be categorized into 0 = no deficit, 1 = mild deficit, 2 = moderate deficit and 3 = severe deficit. The total score includes 15 points, 0 meaning no deficit and 15 severe deficits. Cross-sectional and longitudinal data from 201 baseline and 71 follow up patients were analyzed.

RESULTS

Baseline ShoCo scale results were 5.9 ± 2.9. No significant differences between patients with Richardson syndrome (PSP-RS) and variants (vPSP) could be detected in the PSP-ShoCo scale scores (PSP-RS 6.1 ± 3.0, n = 160, vPSP 5.1 ± 2.6, n = 41, P = 0.057). The scale showed good correlation with established scores (eg, Montreal cognitive assessment r = -0.535, P = 0.001). The ShoCo scale showed significant annualized change within the PSP-RS patients (baseline 6.2 ± 2.9, follow up 6.9 ± 3.1, annualized diff. 1.0 ± 3.1, n = 57, P = 0.022).

CONCLUSIONS

The ShoCo scale seems a promising and valid tool to measure specific neuropsychological disabilities of PSP patients in clinical routine and research.

Differences and contributors to global cognitive performance in the underrepresented Latinx Parkinson's disease population

Objective: Despite significant progress in understanding the factors influencing cognitive function in Parkinson's disease (PD), there is a notable gap in data representation for the Latinx population. This study aims to evaluate the contributors to and disparities in cognitive performance among Latinx patients with PD. Methods: A retrospective analysis was conducted based on cross-sectional data encompassing demographic, environmental, motor, and non-motor disease characteristics from the Latin American Research Consortium on the Genetics of PD (LARGE-PD) and the Parkinson's Progression Markers Initiative (PPMI) cohorts. Linear regression multivariable models were applied to identify variables affecting Montreal Cognitive Assessment (MoCA) scores, accounting for age, sex, and years of education. Results: The analysis comprised of 3,054 PD patients (2,041 from LARGE-PD and 1,013 from PPMI) and 1,303 Latinx-controls. Latinx-PD patients (mean age 63.0 ± 11.8, 56.8% male) exhibited a significantly lower average MoCA score (p < .001) compared to white Non-Hispanic PD patients from PPMI (mean age 67.5 ± 9.9, 61.7% male). This difference persisted when comparing the Latinx-PD to the Latinx-controls (mean age 58.7 ± 9.3, 33.2% male; p < .001). Factors significantly associated with better MoCA scores in Latinx-PD included unilateral symptom onset (p = .009), and higher educational attainment (p < .001). Conversely, those associated with worse scores included the use of dopamine agonists (p = .01), previous tobacco use (p = .01), older age (p < .001), and a higher Hoehn and Yahr scale score (p < .001). Conclusions: Latinx-PD patients demonstrated significantly lower cognitive scores compared to their white non-Hispanic PD counterparts and Latinx-controls. These results highlight the importance of interpreting MoCA scores in a nuanced manner within diverse populations.

Neuroanatomical heterogeneity drives divergent cognitive and motor trajectories in Parkinson's disease subtypes

INTRODUCTION

Cognitive symptoms of Parkinson's disease (PD) may initially present subtly, often overshadowed by more noticeable motor symptoms. However, as PD progresses, predicting which individuals will experience significant cognitive decline becomes challenging due to variability, suggesting distinct PD subtypes with varying cognitive trajectories. This study aimed to identify early PD subtypes based on patterns of gray matter atrophy in brain regions associated with cognition and assess their distinct patterns of cognitive change over time. Recognizing PD primarily as a movement disorder, we also evaluated their motor symptoms.

METHODS

We analyzed T1-weighted MRI data, cognitive, and motor scores from 114 de novo PD patients and 120 healthy controls. Multivariate gray matter volumetric distances (MGMV) across frontal, subcortical, parietal, temporal, and occipital regions were computed, and K-means clustering was used to identify PD subtypes. Subsequently, cognitive assessments were compared between subtypes at baseline and 48 months using linear mixed-effects models and reliable change indices. Motor-symptom changes were assessed using linear mixed-effects models.

RESULTS

Two PD subtypes were identified from baseline MRI. Subtype 1 showed significantly higher MGMV in frontal (p < 0.001) and subcortical (p < 0.001) regions, indicating atrophy. At 48 months, subtype 1 had poorer global cognitive performance than subtype 2 (p = 0.005) and faster progression of postural instability and gait disturbance (p = 0.04).

CONCLUSIONS

PD subtypes identified early by distinct frontal and subcortical atrophy patterns exhibited divergent trajectories of cognitive decline and worsening motor symptoms over time, underscoring the neuroanatomical heterogeneity that drives clinical variability in PD.

Exploring the intersection between orthostatic hypotension and daytime sleepiness in Parkinson's disease

INTRODUCTION

Daytime sleepiness, reported in about 50 % of patients with Parkinson's disease (PD), is associated with high morbidity, poor quality of life and increased risk for accidents. While an association between dysautonomia and daytime sleepiness in early, de-novo PD has been reported, our understanding of the role of medications, cognitive status and co-morbidites on this relationship is inadequate.

METHODS

Data were analyzed from the prospective Cincinnati Cohort Biomarkers Program. The primary outcome of interest was excessive daytime sleepiness (EDS), as measured by the Epworth Sleepiness Scale (ESS; ESS score > 10). The primary exposure variable was orthostatic hypotension (OH). Linear and logistic regression analyses followed by moderated graphical network analyses were conducted to explore the complex association between OH and ESS. Edge weight from graphical network analysis indicates the strength of the association.

RESULTS

Data on 453 subjects with PD were analyzed. Median disease duration was 5.8 years and nearly 90 % were H&Y stage <3. OH was not associated with EDS. OH was associated with depression (edge weight, 0.22) in cognitively impaired patients but not in cognitively normal patients. In addition, depression was associated with ESS (edge weight, 0.37; moderation weight, 0.22) in cognitively impaired patients to a greater extent than in cognitively normal patients (edge weight, 0.22).

CONCLUSIONS

OH is not directly associated with daytime sleepiness in early, treated PD. However, OH seems to be associated with ESS via depression in cognitively impaired patients. This complex relationship deserves additional study.

Effectiveness of a home-based computerized cognitive training in Parkinson's disease: a pilot randomized cross-over study

Introduction

Cognitive symptoms are common in Parkinson's Disease (PD), and digital interventions like telerehabilitation other an accessible way to manage these symptoms. This study aimed to assess the effectiveness of a Home-Based Computerized Cognitive Training (HB-CCT) program in individuals with PD using a pilot randomized cross-over design.

Methods

Twenty-five participants (mean age 69.32 ± 7.21 years, mean MDS-UPDRS III 33.76 ± 14.25) with PD and mild cognitive impairment were enrolled. They underwent neuropsychological assessments at three time points (5-week intervals): Baseline, after the HB-CCTi, and after Standard Care. The HB-CCT consisted of the Neurotablet® platform that was used to target cognitive domains such as Attention, Memory, Perception, Executive Functioning and Language. All participants completed both the Neurotablet intervention and Standard Care blocks in a randomized order. After a Shapiro-Wilk test, non-parametric repeated measures analyses of variance (Friedman's test) and post-hoc comparisons corrected with the Benjamini-Hochberg approach were performed to compare the effects on primary and secondary cognitive outcomes over experimental intervention and Standard Care.

Results

The results from the Friedman analysis revealed significant improvements in Word List Immediate Recall, Digit Span Forward and Complex Figure Recall (all p < 0.001) following the HB-CCT, compared to the Baseline. Additionally, Naming performance showed significant improvement after the HB-CCT (p = 0.02). Significant differences were also observed when comparing the HB-CCT with Standard Care, with improved performance in TMT-A (p = 0.02), Phonemic Fluency (p < 0.01), and Digit Span Forward (p < 0.01).

Discussion

These findings suggest that HB-CCT via Neurotablet can effectively enhance specific cognitive abilities in PD, supporting the role of digital, home-based interventions as feasible strategies to mitigate cognitive decline.

Gait ecological assessment in persons with Parkinson's disease engaged in a synchronized musical rehabilitation program

Data on gait parameters during real-life activities and home rehabilitation programs for Persons with Parkinson's disease (PwPDs) are scarce. Although cueing has been shown to improve their gait in laboratory conditions, few studies have applied this technique in at-home rehabilitation programs. Our study aimed to explore the use of a real-time synchronized beat-step music program for at-home rehabilitation. We conducted a 1-month outdoor gait rehabilitation program called BeatPark (30 min/day, 5 days/week), with 25 PwPDs, using real-time synchronized, cued, music, and measurements through the BeatMove application. We demonstrated that real-world walking with BeatMove exhibited improved gait parameters both within and across sessions. These improvements were further confirmed by the Six-Minute Walk Test conducted in silence in the laboratory before and after the program. Measures in real life are unique tools to enhance rehabilitation programs. Future research incorporating a control group will be essential to fully validate these encouraging findings.

BrainFit: improving executive and subjective cognitive functioning in late-life mood disorders - a double-blind randomized active-controlled study evaluating the effect of online cognitive training

Introduction

Unipolar and bipolar mood disorders in older adults are accompanied by cognitive impairment, including executive dysfunction, with a severe impact on daily life. Up and till now, strategies to improve cognitive functioning in late-life mood disorders (LLMD) are sparse. Therefore, we aimed to assess the efficacy of adaptive, computerized cognitive training (CT) on executive and subjective cognitive functioning in LLMD.

Methods

In this double-blind, randomized controlled study we enrolled patients over the age of 50 with partly remitted LLMD. Over 8 weeks, patients participated in 24 45-minute sessions of computerized multi-domain training (CT) or an active control condition (ACC) (nonspecific cognitive activity). The primary outcome was executive functioning based on the interference score on the STROOP task (not incorporated in the training). Secondary outcomes were subjective cognitive functioning, depressive symptoms and quality of life. Outcomes were assessed before and after training (T1) and at a 3-month follow-up (T2) and analyzed with linear mixed-model analyses.

Results

Thirty-eight patients were included in the study, 22 in the experimental CT and 16 in the ACC. Mean age was 67.3 years and 52.6% was female. Linear mixed-model analyses showed small within-group effect sizes, corresponding to no statistically significant improvement of executive functioning or depression severity in either group. In both groups we did observe an improvement on subjective cognitive functioning over time. From T0 to T1 the mean score of the Cognitive Functioning Questionnaire (CFQ) of the CT group decreased from 52.7 to 46.8 points (p=0.003) and the mean CFQ score of the ACC group decreased from 52.7 to 45.7 points (p<0.001). This effect remained in both groups at follow-up (T2); respectively p=0.002 and p<0.001.The patients in the AAC also showed an improvement of quality of life directly after the training (T1); i.e. the mean quality of life scores improved from 53 to 57 points (p=0.011), but this effect did not remain at follow-up.

Conclusions

This study shows no beneficial effect of an 8-week computerized CT on the primary outcome, i.e, executive functioning. Subjective cognitive functioning did improve in both groups, indicating that frequent cognitive training is advantageous. Future studies with more intensive training could be designed to explore this result further.

Clinical trial registration

clinicaltrials.gov, identifier NCT04006756.

Which motor-cognitive abilities underlie the digital Trail-Making Test? Decomposing various test scores to detect cognitive impairment in Parkinson's disease-Pilot study

Since Parkinson's disease (PD) is a heterogeneous disorder with symptoms, such as tremors, gait and speech disturbances, or memory loss, individualized diagnostics are needed to optimize treatment. In their current form, the typical paper-pencil methods traditionally used to track disease progression are too coarse to capture the subtleties of clinical phenomena. For this reason, digital biomarkers that capture, for example, motor function, cognition, and behavior using apps, wearables, and tracking systems are becoming increasingly established. However, given the high prevalence of cognitive impairment in PD, digital cognitive biomarkers to predict mental progression are important in clinical practice. This pilot study aimed to identify those components of our digital version of the TMT (dTMT) that allow discrimination between PD patients with and without cognitive deficits. A total of 30 healthy control (age 66.3 ± 8.61) and 30 participants with PD (age 68.3 ± 9.66) performed the dTMT using a touch-sensitive tablet to capture enhanced performance metrics, such as the speed between and inside circles. The decomposition of cognitive abilities based on integrating additional variables in the dTMT revealed that the Parkinson's disease group was significantly more sensitive to parameters of inhibitory control. In contrast, the mild cognitive impairment group was sensitive to parameters of cognitive flexibility and working memory. The dTMT allows objective, ecologically valid, and long-term cognitive and fine-motor performance tracking, suggesting its potential as a digital biomarker in neurodegenerative disorders.

Cerebrospinal fluid tau and disease progression in early Parkinson's disease: an 8-year longitudinal study

OBJECTIVE

To explore whether CSF phosphorylated tau-181 (P-tau181) and total tau (T-tau) are associated with disease progression in early PD patients.

METHODS

We analyzed 8-year longitudinal clinical data from 368 early, drug-naive PD patients and 185 matched controls from the Parkinson's Progression Markers Initiative cohort. CSF P-tau181 and T-tau were measured over 5 years, while CSF α-synuclein was measured over 3 years. Dopamine transporter (DAT) imaging was performed at baseline and at 1, 2, and 4 years.

RESULTS

PD patients exhibited significantly lower CSF P-tau181, T-tau and P-tau181/T-tau ratio than controls at each visit. Higher baseline CSF P-tau181 predicted greater increases in Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) III (estimate: 0.067, P < 0.001) and Montreal Cognitive Assessment (MoCA) scores (estimate: -0.010, P = 0.009). Similarly, higher baseline CSF T-tau predicted greater increases in MDS-UPDRS III (estimate: 0.005, P < 0.001) and MoCA scores (estimate: -0.001, P = 0.013). Higher baseline P-tau181/T-tau ratio predicted greater increases in MDS-UPDRS III (estimate: 0.552, P < 0.001) but was not significantly associated with changes in MoCA scores (estimate: -0.052, P = 0.114). CSF P-tau181 (estimate = 84.889, P < 0.001), T-tau (estimate = 8.297, P < 0.001) and P-tau181/T-tau ratio (estimate = 263.425, P < 0.001) were positively correlated with CSF α-synuclein but not correlated with striatal DAT uptake.

CONCLUSIONS

Elevated baseline CSF P-tau181, T-tau and P-tau181/T-tau ratio in early PD patients predict accelerated motor deterioration, with P-tau181 and T-tau also predicting cognitive decline, potentially through interactions with α-synuclein. However, the direct role of tau on nigrostriatal dopaminergic degeneration remains uncertain.

Balance and gait disorders in de novo Parkinson's disease: support for early rehabilitation

BACKGROUND

Postural instability is considered a late complication of Parkinson's disease (PD). However, growing evidence shows that balance and gait problems may occur early in the disease.

OBJECTIVE

To describe balance, gait, and falls/near falls in persons with newly diagnosed, untreated PD ("de novo"), and to compare this with persons with mild-moderate PD (Later PD). In addition, we evaluated differences relative to PD subtypes in de novo PD.

METHODS

De novo (n = 54) and Later (n = 58) PD were assessed regarding motor symptoms, balance, gait, and falls/near falls.

RESULTS

At least 25% of de novo PD had impaired reactive balance and/or comfortable gait speed ≤ 1.0 m/s. At least 50% had abnormal dynamic balance. A third reported balance problems during dual-tasking. Five persons (9%) reported falls/near falls. The median (q1-q3) motor symptom score was 21 (14-28) in de novo PD and 13.5 (9-20) in Later PD (p < 0.001). Later PD performed worse on more balance-demanding tests and a higher percentage of individuals reported falls/near falls (p ≤ 0.048). De novo PIGD PD (n = 10) exhibited worse motor symptoms, reactive and dynamic balance, gait speed, mobility, and freezing of gait as compared to the non-PIGD de novo PD (n = 37) (p ≤ 0.049).

CONCLUSION

Balance and gait were impaired in de novo PD and most pronounced in PIGD subtype. In addition, balance difficulties during dual-tasking and falls/near falls were evident during this early stage. The lower scores of motor symptoms in Later PD did not result in better mobility, balance, or less falls/near falls indicating that medications have less effect on these symptoms.

Predictive value of serum neurofilament light chain for cognitive impairment in Parkinson's disease

Background

Neurofilament light chain (NfL) has recently emerged as a key indicator of neurodegeneration. In this study, our hypothesis is that the levels of blood-derived NfL and its accumulation during the Parkinson's disease (PD) progression could serve as a potential biomarker for predicting subsequent cognitive decline. To investigate this, we conducted a study utilizing a large single-center cohort.

Methods

The study included 193 participants, consisting of 106 cognitively normal PD (PD-CN) patients and 87 normal controls (NC) individuals. Serum NfL concentrations were measured. PD patients were followed up for clinical assessment at an average of 2 ± 0.6 years.

Results

The serum NfL levels were significantly higher in PD-CN patients compared to NC. PD-CN patients and NC at follow-up time exhibited higher serum NfL levels compared to those at baseline. PD patients with high serum NfL levels were found to have a higher likelihood of transitioning from normal cognition to mild cognitive impairment (MCI) or dementia (Hazard ratio (HR) 1.107, 95% confidence intervals (CI) 1.010-1.213, p = 0.030). The area under the curve (AUC) for PD-CN conversion to MCI or dementia at follow-up time was determined to be 0.684 (95% CI 0.569-0.799).

Conclusion

In conclusion, our study found that PD patients have significantly higher levels of serum NfL compared to individuals without PD. Furthermore, serum NfL levels increase as PD progresses and can predict cognitive impairment within a 2-year timeframe. Serum NfL may serve as a feasible, non-invasive biomarker of cognitive progression in PD. However, further studies and functional experiments are needed to validate these findings.

The Effect of Sensory Reweighting on Postural Control and Cortical Activity in Parkinson's Disease: A Pilot Study

Objective

To investigate the effects of sensory reweighting on postural control and cortical activity in individuals with Parkinson's disease (PD) compared to age-matched controls using a virtual reality sensory organization test (VR-SOT).

Design

Cross-sectional pilot study.

Setting

University research laboratory.

Participants

Ten participants with idiopathic Parkinson's disease and 11 age- and sex-matched control participants without neurologic disorders.

Interventions

Not applicable.

Main Outcome Measures

Changes in center of pressure (COP) and electroencephalography (EEG) activity (ie, power) in the alpha band and the theta/beta ratio recorded during the VR-SOT were the main outcome variables.

Results

PD participants exhibited greater COP displacement, particularly in the mediolateral direction across sensory conditions. They also showed increased alpha power when relying on visual inputs and increased theta/beta ratio power when depending on somatosensory inputs.

Conclusion

PD affects sensory reweighting mechanisms involved in postural control, as evidenced by greater COP displacement and altered cortical activity. These findings emphasize the potential of EEG and VR-SOT in understanding and monitoring postural control impairments in PD.

Cognitive function in Parkinson's disease: associations with perivascular space in basal ganglia

BACKGROUND

Cognitive impairment is one of the most common symptoms of Parkinson's disease (PD), and may be detectable through changes in neural features visualized by magnetic resonance imaging (MRI). Mild cognitive impairment is a transitional state between normal aging and dementia, and early recognition of Parkinson's disease with mild cognitive impairment (PD-MCI) can help improve the quality of life and treatment for patients. This study investigated the association of enlarged perivascular space (EPVS) and white matter hyperintensity (WMH) with PD-MCI.

AIMS

This study aimed to evaluate whether EPVS and WMH can be used as potential MRI markers for PD-MCI.

METHODS

This retrospective study involved 200 patients with PD who underwent cranial MRI in our hospital from April 2021 to April 2022. Patients were divided into those with no cognitive impairment (PD-NCI) or mild cognitive impairment. Uni- and multivariate logistic regression analyzed associations of EPVS, WMH, and clinicodemographic characteristics with cognitive decline.

RESULTS

Univariate regression identified severe EPVS in basal ganglia, severe WMH, older age, late-onset, male sex, low educational level, longer duration of disease, low triglycerides, low uric acid, and low scores on the Mini-mental State Exam as risk factors for PD-MCI. After adjusting for clinicodemographic risk factors in multivariate regression, low education level and EPVS in basal ganglia remained risk factors for cognitive impairment.

CONCLUSIONS

Severe EPVS in basal ganglia and poor education, but not WMH, are independent risk factors of PD-MCI. Our findings suggest that non-invasive detection of EPVS in basal ganglia by MRI may be a valuable early indicator of cognitive decline in PD patients.

Unraveling the stride: exploring the influence of neurogenic orthostatic hypotension on gait and balance in Parkinson's disease

PURPOSE

Neurogenic orthostatic hypotension (nOH) and gait impairment are frequent sources of disability in Parkinson's disease (PD). However, the impact of nOH on balance and gait features remains unclear. This cross-sectional study aimed to assess the influence of nOH on postural and gait parameters in a cohort of patients with PD by means of wearable inertial sensors.

METHODS

Gait and balance were assessed using Opal inertial sensors. nOH was defined as sustained systolic blood pressure (BP) drop ≥ 20 mmHg or diastolic BP drop ≥ 10 mmHg within 3 min of standing, with a ΔHR/ΔSBP ratio ≤ 0.5 bpm/mmHg. Analysis of covariance was performed to evaluate differences in gait/balance features between patients with and without nOH, adjusting for age, cognitive status, and motor disability. Moreover, we performed the same analysis considering the presence of hemodynamically relevant nOH (orthostatic mean BP ≤ 75 mmHg).

RESULTS

A total of 82 patients were enrolled, 26 with nOH (31.7%), of which 13 presented with hemodynamically relevant nOH. After correcting for confounders, nOH was independently associated with lower gait speed (p = 0.027), shorter stride length (p = 0.033), longer time for postural transitions (p = 0.004), and increased postural sway (p = 0.019). These differences were even more pronounced in patients with hemodynamically relevant nOH. Higher postural sway was associated with a 7.9-fold higher odds of falls (p = 0.040).

CONCLUSIONS

Our study presents an objective demonstration of the independent negative impact of nOH on gait and balance in PD, emphasizing the need for careful detection and management of nOH to mitigate gait and balance disturbances in PD.

Optimal MMSE and MoCA cutoffs for cognitive diagnoses in Parkinson's disease: A data-driven decision tree model

BACKGROUND

Detecting cognitive impairment in Parkinson's disease (PD) is challenging due to diverse manifestations and outdated diagnostic criteria. Cognitive screening tools, as Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA), are adopted worldwide, but despite several cutoffs has been proposed for PD, no consensus has been reached, hindered by limited sample sizes, lack of validation, and inconsistent age- and education-adjustments.

OBJECTIVES

Determine the optimal MMSE and MoCA cutoffs in a large PD cohort, spanning from normal cognition (PD-NC), mild cognitive impairment (PD-MCI) to dementia (PDD), and develop a decision tree model to assist physicians in cognitive workups.

METHODS

Our retrospective Italian multicenter study involves 1780 PD, cognitively diagnosed with a level-II assessment: PD-NC(n = 700), PD-MCI(n = 706), and PDD(n = 374). Optimal cutoffs (for raw scores) were determined through ROC analysis. Then, a machine learning approach-decision trees-was adopted to validate and analyze the possible inclusion of other relevant clinical features.

RESULTS

The decision tree model selected as primary feature a MMSE cutoff ≤24 to predict dementia, and a score ≤ 27 for PD-MCI. To enhance PD-MCIvs.PD-NC accuracy, it also recommends including a MoCA score ≤ 22 for PD-MCI, and > 22 for PD-NC. Age and education were not selected as relevant features for the cognitive workup. Both MoCA and MMSE cutoffs exhibited high sensitivity and specificity in detecting PD cognitive statues.

CONCLUSIONS

For the first time, a clinical decision tree model based on robust MMSE and MoCA cutoffs has been developed, allowing to diagnose PD-MCI and/or PDD with a high accuracy and short administration time.

Psychiatric predictors of quality of life in Parkinson's disease: A three-year longitudinal study

INTRODUCTION

Parkinson's disease (PD) is associated with worsened quality of life (QOL) over time. Few longitudinal studies exist investigating the relationship of psychiatric comorbidities with QOL in people with PD (PwP). We sought to determine specific psychiatric symptoms associated with decreasing QOL in PwP over time.

METHODS

We recruited PwP without dementia from a movement disorders clinic at an academic medical center. Participants were evaluated annually with motor and neuropsychological assessments at each visit. QOL was measured using the Parkinson's Disease Questionnaire-39 (PDQ-39). We assessed psychiatric symptoms, including depression (Beck Depression Inventory II, BDI-II), anxiety (Beck Anxiety Index, BAI), and apathy (Apathy Scale). Psychosis and impulse control disorders (ICDs) were recorded as present or absent. Using random coefficient regression, we analyzed psychiatric features associated with worsened QOL in PwP over three years.

RESULTS

From the 105 participants enrolled at baseline, 67 completed three years of follow up. Mean PDQ-39 scores increased from 16.0 at baseline to 19.8 at year three. In multivariate analysis, higher BDI-II scores, BAI scores, and apathy scores were uniquely associated with worsened QOL over time (p < 0.001 for all measures), while presence of ICDs (p = 0.18) or psychosis (p = 0.10) were not. Changes in the BAI score and the BDI-II score exerted similar effects on the overall PDQ-39 score.

CONCLUSION

Depression, anxiety, and apathy are all associated with worsening quality of life over time in PwP, while presence of ICDs and psychosis are not. Treatment of these symptoms may lead to improved QOL in PwP.

The association of motor reserve and clinical progression in Parkinson's disease

OBJECTIVE

To explore the association of motor reserve (MR) and clinical progression in Parkinson's disease.

METHODS

This longitudinal study using data from the Parkinson's progression markers initiative. Patients with de novo PD who underwent dopamine transporter scans at baseline and finished at least five years clinical follow-up assessments (including motor, cognitive, and non-motor symptoms) were included. The individual MR of PD patients were estimated based on initial motor deficits and striatal dopamine depletion using a residual model. Linear mixed-effects models (LME) were performed to examine the associations of baseline MR and clinical progression.

RESULTS

A total of 303 de novo PD patients were included and the mean follow-up time was 8.95 years. Results of LME models revealed that the baseline MR was associated with motor, cognitive, and non-motor symptoms in PD patients. There was a significant interaction between MR and disease duration for longitudinal changes in motor (p < 0.001), cognitive (p = 0.028) and depression symptoms (p = 0.014). PD patients with lower MR had a more rapid progression to postural instability and cognitive impairment compared with those with higher MR (p = 0.002 and p = 0.001, respectively).

CONCLUSIONS

The baseline MR of PD patients were associated with motor and non-motor symptoms and can predicted disease prognosis, suggesting that the initial MR in PD would be associated with the individual's capacity to cope with neurodegenerative process as well as comprehensive prognosis.

Clinical and cognitive features associated with psychosis in Parkinson's disease: a longitudinal study

Background

Parkinson's disease psychosis (PDPsy) is associated with increased nursing home placement and mortality and is closely linked with cognitive dysfunction.

Objective

Assess the clinical and cognitive features associated with PDPsy in patients without dementia.

Methods

We prospectively recruited people with Parkinson's disease (PwP) without dementia for a 3-year, longitudinal study at an outpatient movement disorders clinic. Participants completed annual visits involving assessment of motor and non-motor symptoms including neuropsychological testing. PDPsy was defined as the recurring presence of visual illusions, sense of presence, hallucinations, or delusions for at least 1 month. Using generalized estimating equations, we conducted two sets of analyses to separately assess the clinical and the cognitive predictors of PDPsy.

Results

We enrolled 105 participants. At baseline, mean age was 67.8 (SD = 8.0), median disease duration was 4.9 years (IQR: 3.4-7.7), and mean MoCA was 24.8 (SD = 2.3). Prevalence of PDPsy increased over 3 years from 31% (n = 32) to 39% (n = 26). Forty-five participants (43%) experienced PDPsy. Visual illusions were most common (70%, n = 84), followed by hallucinations (58.3%, n = 70). In multivariate analysis, of the clinical variables, only depressive symptoms [OR 1.09, 95% CI: (1.03, 1.16), p = 0.004] increased the odds of PDPsy; of the cognitive variables, only Trail Making Test B-A scores [OR 1.43, 95% CI: (1.06, 1.93), p = 0.018] significantly increased the odds of PDPsy.

Conclusions

In PwP without dementia, depressive symptoms were associated with increased risk of PDPsy. Executive/attentional dysfunction was also associated with PDPsy and may mark the transition from isolated minor hallucinations to more complex psychotic symptoms.

Altered gait speed and brain network connectivity in Parkinson's disease

Slow gait speed and disrupted brain network connectivity are common in patients with Parkinson's disease (PD). This study aimed to clarify the relationship between gait speed and clinical characteristics in PD, and explore the underlying brain network mechanisms. Forty-two PD patients and 20 healthy controls (HC) were recruited. Statistical independent component analysis and correlation analysis were employed to investigate underlying neural mechanisms and relationships. PD patients exhibited significantly slower gait speed, which showed a significant negative correlation with postural instability and gait disturbance scores. Network connectivity analysis revealed decreased intranetwork functional connectivity (FC) within visual network (VN) and cerebellum network (CN), but increased internetwork FC between CN and both sensorimotor network (SMN) and frontoparietal network (FPN) in PD patients compared to HC. The slow gait speed PD subgroup demonstrated increased intranetwork FC within SMN and VN, along with decreased FC between VN and both FPN and default mode network. Correlation analyses revealed negative correlation between gait speed and FC of CN and positive correlation to FC of CN-SMN. Our study identified relationships between gait speed and clinical characteristics, and corresponding network connectivity alterations in PD patients, providing insights into the neural mechanisms underlying gait impairments in PD.

Metabolic biomarkers of appetite control in Parkinson's disease patients with and without cognitive impairment

BACKGROUND

Appetite dysregulation in Parkinson's Disease (PD) appears to be linked to physical and cognitive deterioration. PD patients with and without cognitive impairment (CI) were compared to an age-matched control group to explore predictors of appetite control in fasting and post-prandial conditions.

METHODS

Fifty-five patients were recruited and divided into three groups: twenty controls (age: 74 y, BMI: 25.8 kg/m2), nineteen PD patients without CI (72.5 y, 25.1 kg/m2) and sixteen PD patients with CI (74.3 y, 24.0 kg/m2). Self-reported appetite perception and circulating blood metabolic biomarkers were measured in fasting and over a 3-h post-prandial period. Biomarkers included glucose, insulin, tumour necrosis factor alpha (TNF-α), leptin, acyl-ghrelin, total ghrelin, peptide YY (PYY), glucagon like peptide 1 (GLP-1), insulin growth factor 1 (IGF-1), growth factor (GF) and triglycerides. Patients were then provided with a mixed meal to eat ad libitum with the aim to evaluate links between metabolic biomarkers and control of energy intake.

RESULTS

PD patients with CI had a significant lower protein intake (7.4 ± 2.5 g, p = 0.01) compared to controls (21.9 ± 3.1 g) and PD patients without CI (14.3 ± 3.0 g). Post-prandial plasma GLP-1 concentrations were associated with decreased hunger perception (B±SE, -5.3 ± 2.4  mm·h-1, p = 0.04). PYY concentrations were significantly associated with GLP-1 in fasting (r = 0.40, p = 0.005) and post-prandial (r = 0.46, p < 0.001) conditions. In a multivariate model, post-prandial PYY concentrations were a significant predictor of ad libitum energy intake in all subjects (B±SE, -87.5 ± 34.9 kcal, p = 0.01) and in patients with PD (B±SE, -106.8 ± 44.9 kcal, p = 0.04).

CONCLUSIONS

PYY and GLP-1 appeared to influence appetite control in PD patients and their roles merit further investigation.

German Society of Neurology guidelines for the diagnosis and treatment of cognitive impairment and affective disorders in people with Parkinson's disease: new spotlights on diagnostic procedures and non-pharmacological interventions

BACKGROUND AND OBJECTIVE

Cognitive impairment and dementia as well as affective disorders are common and debilitating syndromes that develop in people with Parkinson's disease (PwPD). The authors summarized recommendations for the 2023 updated German guidelines on "Parkinson's disease" from the German Neurological Society (DGN), focusing on the diagnosis and treatment of these disorders.

METHODS

The recommendations were based on literature reviews, other relevant guidelines, and expert opinions.

RESULTS

Measurements to assess cognitive and affective states were reviewed for psychometric properties, use in routine clinical practice, and availability in German. To improve mild cognitive impairment, cognitive training and physical aerobic training are recommended. To treat Parkinson's disease (PD)-related dementia, cognitive stimulation (as a non-pharmacological intervention) and acetylcholinesterase inhibitors (AChEIs, i.e., rivastigmine) are recommended. Cognitive behavioral therapy is recommended to treat depression, anxiety, and fear of progression. Physical interventions are recommended to treat depression, fatigue, and apathy. Optimized dopaminergic treatment is the first-line pharmacological strategy recommended to manage depression, apathy, anhedonia, fatigue, and mood swings. Major depression can be additionally treated using venlafaxine or desipramine, while moderate depression can be treated pharmacologically according to its clinical phenotype (psychomotor retardation or agitation) and comorbidities (e.g., sleep disturbances, pain). Venlafaxine and nortriptyline can be used to treat anhedonia, while citalopram can be used for anxiety.

CONCLUSIONS

In addition to the updated pharmacological treatment options, new insights into recommendations for standardized diagnostics and non-pharmacological interventions were provided for the German health care system. However, more studies are needed to explore the full potential of non-pharmacological interventions to treat and prevent cognitive impairment and affective disorders.

Impact of Dance or Music and Meditation on the Progression of Parkinson Disease With Mild or Moderate Severity: Protocol for a Pilot Randomized Controlled Trial

BACKGROUND

Parkinson disease (PD) is a progressive neurodegenerative disorder characterized by motor dysfunctions and nonmotor symptoms. Current treatments do not alter disease progression, highlighting the need for alternative therapies. Music, dance, and mindfulness meditation have shown the potential to improve symptoms and quality of life in patients with PD.

OBJECTIVE

This study aims to evaluate the effectiveness of dance or music and meditation on PD progression, cognitive functions, mood, behavior, and caregiver burden.

METHODS

This study is a single-blinded, longitudinal, parallel, randomized controlled trial. The participants consist of 30 patients with mild to moderate PD residing in Mumbai, India, who can physically participate in the activities. The exclusion criteria include advanced PD, severe balance issues, age >80 years, and other movement disorders. Participants in the intervention group will engage in dance or music sessions and guided meditation thrice weekly for 6 months. The control group will continue their usual activities and medication. The primary outcome is the progression of PD symptoms, measured using the Unified Parkinson's Disease Rating Scale I-III, and quality of life, measured using the Parkinson's Disease Questionnaire-39. The secondary outcomes include cognitive functions (Mini-Mental State Examination), mood (Beck Depression Inventory and Parkinson Anxiety Scale), mobility (timed up and go and Berg Balance Test), behavioral disorders (Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease Rating Scale), and caregiver burden (Zarit Burden Interview and Parkinson's Disease Questionnaire-Carer).

RESULTS

Data collection was completed in February 2024, with 28 participants finishing the study (intervention group: n=15, 54% and control group: n=13, 46%). Data analysis is underway, with results expected to be published in December 2024.

CONCLUSIONS

This study aims to provide significant insights into the effectiveness of dance or music and meditation in improving the quality of life and slowing the progression of PD. The findings are anticipated to support using these nonpharmaceutical therapies as complementary approaches to managing PD.

TRIAL REGISTRATION

CTRI/2023/03/051064; https://tinyurl.com/2xdus53j.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/59018.

Cholinergic deficiency in Parkinson's disease patients with visual hallucinations

Visual hallucinations can increase the burden of disease for both patients with Parkinson's disease and their caregivers. Multiple neurotransmitters have been implicated in the neuropathology of visual hallucinations, which provide targets for treatment and prevention. In this study, we assessed the association between cholinergic denervation and visual hallucinations in Parkinson's disease in vivo, using PET imaging of the cholinergic system. A total of 38 patients with Parkinson's disease participated in this study. A group of 10 healthy subjects, matched for age, sex and education, was included for comparison. None of the participants used cholinergic drugs. Thirteen patients who had experienced visual hallucinations in the past month (VH+) were compared with 20 patients who had never experienced visual hallucinations in their lives (VH-). Cholinergic system integrity was assessed with PET imaging using 18F-fluoroethoxybenzovesamicol as the tracer. We assessed the differences in tracer uptake between groups by cluster-based analysis and by analysis of predefined regions of interest consisting of the ventral visual stream, the dorsal attentional network, the ventral attentional network and the lateral geniculate nucleus and mediodorsal nucleus of the thalamus. The Parkinson's disease group (n = 38) showed an extensive pattern of decreased tracer uptake throughout the brain compared with the controls (n = 10). Within the Parkinson's disease group, the VH+ group (n = 13) showed a cluster of decreased tracer uptake compared with the VH- group (n = 20), which covered most of the left ventral visual stream and extended towards superior temporal areas. These results were mirrored in the regions of interest-based analysis, in which the VH+ group showed the strongest deficits in the left inferior temporal gyrus and the left superior temporal gyrus compared with the VH- group. Visual hallucinations in Parkinson's disease are associated with a marked cholinergic deficiency in the left ventral visual stream and the left superior temporal lobe, in addition to an extensive global cholinergic denervation in the general Parkinson's disease population.

A fixel-based analysis of white matter reductions early detects Parkinson disease with mild cognitive impairment

BACKGROUND

White matter (WM) tract alterations are early signs of cognitive impairment in Parkinson disease (PD) patients. Fixel-based analysis (FBA) has advantages over traditional diffusion tensor imaging in managing complex and crossing fibers. We used FBA to measure fiber-specific changes in patients with PD mild cognitive impairment (PD-MCI) and PD normal cognition (PD-NC).

METHODS

Seventy-one patients with PD without dementia were included: 39 PD-MCI and 32 PD-NC. All underwent diffusion-weighted imaging, clinical examinations, and tests to evaluate their cognitive function globally and in five cognitive domains. FBA was used to investigate fiber-tract alterations and compare PD-MCI with PD-NC subjects. Correlations with each cognitive test were analyzed.

RESULTS

Patients with PD-MCI were significantly older (p = 0.044), had a higher male-to-female ratio (p = 0.006) and total Unified Parkinson's Disease Rating Scale score (p = 0.001). All fixel-based metrics were significantly reduced within the body of the corpus callosum and superior corona radiata in PD-MCI patients (family-wise error-corrected P value < 0.05) compared with PD-NC patients. The cingulum, superior longitudinal fasciculi, and thalamocortical circuit exhibited predominantly fiber-bundle cross-section (FC) changes. In regression analysis, reduced FC values in cerebellar circuits were associated with poor motor function in PD-MCI patients and poor picture-naming ability in PD-NC patients.

CONCLUSIONS

PD-MCI patients have significant WM alterations compared with PD-NC patients. FBA revealed these changes in various bundle tracts, helping us to better understand specific WM changes that are functionally implicated in PD cognitive decline. FBA is potentially useful in detecting early cognitive decline in PD.

Multidisciplinary care in Parkinson's disease

Parkinson's Disease (PD) is a multifaceted and progressive disorder characterized by a diverse range of motor and non-motor symptoms. The complexity of PD necessitates a multidisciplinary approach to manage both motor symptoms, such as bradykinesia, gait disturbances and falls, and non-motor symptoms, including cognitive dysfunction, sleep disturbances, and mood disorders, which significantly affect patients' quality of life. Pharmacotherapy, particularly dopaminergic replacement therapy, has advanced to alleviate many symptoms. However, these medications can also induce side effects or aggravate symptoms like hallucinations or orthostatic dysfunction, highlighting the need for comprehensive patient management. The optimal care for PD patients involves a team of specialists, including neurologists, physical and occupational therapists, speech-language pathologists, psychologists, and other medical professionals, to address the complex and individualized needs of each patient. Here, we illustrate the necessity of such a multidisciplinary approach in four illustrative PD cases with different disease stages and motor and non-motor complications. The patients were treated in different treatment settings (specialized outpatient clinic, day clinic, inpatient care including neurorehabilitation). The biggest challenge lies in organizing and implementing such comprehensive care effectively across different clinical settings.

Sensitivity of Clock Drawing Test Alone to Screen for Cognitive Impairment in Patients with Parkinson's Disease

Objectives

Cognitive impairment is a prevalent non-motor symptom of Parkinson's disease (PD), significantly impacting patient quality of life. The Clock Drawing Test (CDT) evaluates cognitive abilities, including planning, organization, and executive functions such as attention, memory, and visuospatial skills. This study aimed to determine the sensitivity of the CDT in diagnosing cognitive impairment in PD.

Methods

We reviewed the records of 44 PD patients (16 female, 28 male) diagnosed with dementia (30 patients) or mild cognitive impairment (14 patients) between 2018 and 2022. These patients were compared to 106 visitors to the neurological outpatient clinic, serving as a control group. A separate researcher assessed the patients' CDT scores, maintaining confidentiality of all other patient data except age and education level.

Results

Among the 44 PD patients, two with mild cognitive impairment were rated as normal, while all PD dementia cases were identified solely through the CDT. In the healthy control group, 72 out of 106 individuals reported no cognitive complaints, whereas 34 individuals (32.1%) reported cognitive complaints as assessed by a blind investigator. The CDT demonstrated a positive predictive value of 55.3% and a negative predictive value of 97.3%. Sensitivity was calculated at 95.5%, and specificity was 67.9%.

Conclusion

The findings suggest that the CDT is sensitive in detecting cognitive impairment in PD patients with cognitive deficits. While the CDT serves as an effective rapid screening tool, high scores indicate the absence of cognitive impairment, but low scores alone are insufficient for a definitive diagnosis of dementia. Comprehensive neurological evaluation and detailed cognitive assessment remain essential for confirming dementia diagnoses.

Long-Term Dementia Risk in Parkinson Disease

BACKGROUND AND OBJECTIVES

It is widely cited that dementia occurs in up to 80% of patients with Parkinson disease (PD), but studies reporting such high rates were published over two decades ago, had relatively small samples, and had other limitations. We aimed to determine long-term dementia risk in PD using data from two large, ongoing, prospective, observational studies.

METHODS

Participants from the Parkinson's Progression Markers Initiative (PPMI), a multisite international study, and a long-standing PD research cohort at the University of Pennsylvania (Penn), a single site study at a tertiary movement disorders center, were recruited. PPMI enrolled de novo, untreated PD participants and Penn a convenience cohort from a large clinical center. For PPMI, a cognitive battery is administered annually, and a site investigator makes a cognitive diagnosis. At Penn, a comprehensive cognitive battery is administered either annually or biennially, and a cognitive diagnosis is made by expert consensus. Interval-censored survival curves were fit for time from PD diagnosis to stable dementia diagnosis for each cohort, using cognitive diagnosis of dementia as the primary end point and Montreal Cognitive Assessment (MoCA) score <21 and Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part I cognition score ≥3 as secondary end points for PPMI. In addition, estimated dementia probability by PD disease duration was tabulated for each study and end point.

RESULTS

For the PPMI cohort, 417 participants with PD (mean age 61.6 years, 65% male) were followed, with an estimated probability of dementia at year 10 disease duration of 9% (site investigator diagnosis), 15% (MoCA), or 12% (MDS-UPDRS Part I cognition). For the Penn cohort, 389 participants with PD (mean age 69.3 years, 67% male) were followed, with 184 participants (47% of cohort) eventually diagnosed with dementia. The interval-censored curve for the Penn cohort had a median time to dementia of 15 years (95% CI 13-15); the estimated probability of dementia was 27% at 10 years of disease duration, 50% at 15 years, and 74% at 20 years.

DISCUSSION

Results from two large, prospective studies suggest that dementia in PD occurs less frequently, or later in the disease course, than previous research studies have reported.

Changes in electrophysiological aperiodic activity during cognitive control in Parkinson's disease

Cognitive symptoms in Parkinson's disease are common and can significantly affect patients' quality of life. Therefore, there is an urgent clinical need to identify a signature derived from behavioural and/or neuroimaging indicators that could predict which patients are at increased risk for early and rapid cognitive decline. Recently, converging evidence identified that aperiodic activity of the EEG reflects meaningful physiological information associated with age, development, cognitive and perceptual states or pathologies. In this study, we aimed to investigate aperiodic activity in Parkinson's disease during cognitive control and characterize its possible association with behaviour. Here, we recorded high-density EEG in 30 healthy controls and 30 Parkinson's disease patients during a Simon task. We analysed task-related behavioural data in the context of the activation-suppression model and extracted aperiodic parameters (offset, exponent) at both scalp and source levels. Our results showed lower behavioural performances in cognitive control as well as higher offsets in patients in the parieto-occipital areas, suggesting increased excitability in Parkinson's disease. A small congruence effect on aperiodic parameters in pre- and post-central brain areas was also found, possibly associated with task execution. Significant differences in aperiodic parameters between the resting-state, pre- and post-stimulus phases were seen across the whole brain, which confirmed that the observed changes in aperiodic activity are linked to task execution. No correlation was found between aperiodic activity and behaviour or clinical features. Our findings provide evidence that EEG aperiodic activity in Parkinson's disease is characterized by greater offsets, and that aperiodic parameters differ depending on arousal state. However, our results do not support the hypothesis that the behaviour-related differences observed in Parkinson's disease are related to aperiodic changes. Overall, this study highlights the importance of considering aperiodic activity contributions in brain disorders and further investigating the relationship between aperiodic activity and behaviour.

Large-scale evidence for the validity of remote MoCA administration among people with cerebellar ataxia

Objective: For over half a century, studies of rare diseases using in-person cognitive tools have faced challenges, such as long study periods and small sample sizes (e.g. n = 10). The Montreal Cognitive Assessment (MoCA) was widely employed to assess mild cognitive impairment (MCI). We aimed to validate a modified online version of the MoCA in a large sample of a rare disease (population prevalence < .01%). Method: First, we analyzed 20 previous findings (n = 1,377), comparing the MoCA scores between large groups of neurotypically healthy (NH; n = 837) and cerebellar ataxia (CA; n = 540), where studies were conducted in-person. Second, we administered the MoCA in-person to a group of NH (n = 41) and a large group of CA (n = 103). Third, we administered a video conferencing version of the MoCA to NH (n = 38) and a large group of CA (n = 83). Results: We observed no performance differences between online and in-person MoCA administration in the NH and CA groups (p > .05, η2 = 0.001), supporting reliability. Additionally, our online CA group had lower MoCA scores than the NH group (p < .001, Hedges' g = 0.68). This result is consistent with previous studies, as demonstrated by our forest plot across 20 previous in-person findings, supporting construct validity. Conclusion: The results indicate that an online screening tool is valid in a large sample of individuals with CA. Online testing is not only time and cost-effective, but facilitates disease management and monitoring, ultimately enabling early detection of MCI.

Associations between cognitive screening performance and motor symptoms in Parkinson's disease:a systematic review and meta-analysis

Although the most prominent symptoms of Parkinson's disease (PD) are those impacting movement, cognitive dysfunction is prevalent and often presents early in the disease process. Individuals with cognitive symptoms of PD often complete cognitive screening, making it important to identify factors associated with cognitive screening performance to ensure prompt and accurate detection of cognitive impairments.

Objective

Despite a body of research examining relationships between motor symptoms and cognitive dysfunction in PD, no prior study has undertaken a systematic review of the magnitude of the relationship between motor symptoms and cognitive screening performance in PD.

Methods

This study was a systematic review and meta-analysis of the relationship between cognitive screening performance, as assessed by the Montreal Cognitive Assessment (MoCA), and motor symptoms of PD. After the systematic screening, 20 studies were included, and meta-regressions using mixed-effects models were conducted.

Results

Motor symptoms across included studies were relatively mild, but average MoCA scores were at the established cutoff for risk of dementia in PD. The average disease duration was 5 years. Consistent with hypotheses, more severe motor symptoms were associated with lower MoCA scores (r=-0.22 (95%CI -0.29 to -0.16), p<0.001), indicating worse cognitive functioning.

Conclusion

The results indicate a significant negative correlation between MoCA performance and motor symptoms of PD. Average MoCA scores captured early disease-stage cognitive impairment when motor symptoms remained relatively mild. Serial screening for cognitive impairment beginning early in the disease course may be of benefit to ensure that cognitive dysfunction is detected as it arises.

Effects of Age and Parkinson's Disease on the Relationship between Vocal Fold Abductory Kinematics and Relative Fundamental Frequency

PURPOSE

This study reports on two experiments to examine vocal fold abduction and its relationship with relative fundamental frequency (RFF), considering two attributes that have been shown to elicit group differences in RFF: age (Experiment 1) and Parkinson's disease (PD; Experiment 2).

METHODS

For both experiments, simultaneous acoustic and nasendoscopic recordings were collected as participants produced the utterance, /ifi/. RFF values were computed from the acoustic signal, whereas abduction duration and glottic angle at voicing offset were identified from the laryngoscopic images. In Experiment 1, 50 speakers with typical voices (18-83 years) were analyzed to examine (1A) the effects of speaker age on individual outcome measures (RFF, abduction duration, glottic angle) via Pearson's correlation coefficients, and (1B) the effects of abductory measures and age on RFF via an analysis of covariance. In Experiment 2, 20 speakers with PD and 20 matched controls were analyzed to examine (2A) the effects of group (with/without PD) on outcome measures via an analysis of variance, and (2B) the relationship of RFF with abduction duration, glottic angle, and age when considering group via an analysis of covariance.

RESULTS

Age demonstrated a significant, negative relationship with glottic angle (1A) but was not a significant factor when examining the relationship of vocal fold abduction and RFF (1B). Speaker group (with/without PD) demonstrated a significant effect on measures of RFF and abduction duration (2A) but was not a significant factor when examining the relationship of vocal fold abduction and RFF (2B).

CONCLUSIONS

RFF is sensitive to changes in vocal fold abductory patterns during devoicing, irrespective of speaker age or PD status.

Subthalamic DBS does not restore deficits in corticospinal suppression during movement preparation in Parkinson's disease

OBJECTIVE

Parkinson's disease (PD) patients exhibit changes in mechanisms underlying movement preparation, particularly the suppression of corticospinal excitability - termed "preparatory suppression" - which is thought to facilitate movement execution in healthy individuals. Deep brain stimulation (DBS) of the subthalamic nucleus (STN) being an attractive treatment for advanced PD, we aimed to study the potential contribution of this nucleus to PD-related changes in such corticospinal dynamics.

METHODS

On two consecutive days, we applied single-pulse transcranial magnetic stimulation to the primary motor cortex of 20 advanced PD patients treated with bilateral STN-DBS (ON vs. OFF), as well as 20 healthy control subjects. Motor-evoked potentials (MEPs) were elicited at rest or during movement preparation in an instructed-delay choice reaction time task including left- or right-hand responses. Preparatory suppression was assessed by expressing MEPs during movement preparation relative to rest.

RESULTS

PD patients exhibited a deficit in preparatory suppression when it was probed on the responding hand side, particularly when this corresponded to their most-affected hand, regardless of their STN-DBS status.

CONCLUSIONS

Advanced PD patients displayed a reduction in preparatory suppression which was not restored by STN-DBS.

SIGNIFICANCE

The current findings confirm that PD patients lack preparatory suppression, as previously reported. Yet, the fact that this deficit was not responsive to STN-DBS calls for future studies on the neural source of this regulatory mechanism during movement preparation.

An interplay between cross-cultural and psychometric factors in the Montreal Cognitive Assessment: Experience from the language of a small nation

The present study aimed to test the hypothesis that the total word length on the Memory subtest of the Czech version of the MoCA, which is 12 syllables compared to the English version of 7 syllables, would have a significant effect on Delayed Recall scores compared to the newly created well-balanced version of the test (further MoCA-WLE). In the original Czech version of MoCA, we replaced the 12-syllable word list in the Memory subtest with a 7-syllable list (MoCA-WLE) to make it equivalent to the standard English version in this respect. We analyzed data from 83 participants in the original MoCA group (70.63 ± 7.01 years old, 14.61 ± 3.17 years of education, 30.12% males) and 83 participants in the MoCA-WLE group (70.72 ± 6.95 years old, 14.93 ± 3.48 years of education, 30.12% males). We did not find evidence for a significant word-length effect in the original MoCA versus MoCA-WLE Delayed Recall in either the Mann-Whitney U test (W = 3418.0, p = .932) or multilevel binomial regression (b = 0.10, 95% posterior probability interval [-0.46, 0.68]). The present study shows cross-cultural limits in the adaptation of the test material. The results underline the caveats of such an approach to test adaptation. Fortunately, 12-syllables in the MoCA Memory Czech version versus the original 7-syllable list did not show a detectable word-length effect. We did not find evidence for differential item functioning or cultural item bias. The original MoCA Czech version is psychometrically comparable to the original English version.

The prediction model of fall risk for the elderly based on gait analysis

INTRODUCTION

Early screening and identification are crucial for fall prevention, and developing a new method to predict fall risk in the elderly can address the current lack of objectivity in assessment tools.

METHODS

A total of 132 elderly individuals over 80 years old residing in some nursing homes in Shanghai were selected using a convenient sampling method. Fall history information was collected, and gait data during a 10-meter walk were recorded. Logistic regression was employed to establish the prediction model, and a nomogram was used to assess the importance of the indicators. The Bootstrap method was utilized for internal validation of the model, while the verification set was used for external validation. The predictive performance of the model was evaluated using the area under the ROC curve, calibration curve, and decision curve analysis (DCA) to assess clinical benefits.

RESULTS

The incidence of falls in the sample population was 36.4%. The Tinetti Gait and Balance Test (TGBT) score (OR = 0.832, 95% CI: 0.734,0.944), stride length (OR = 0.007, 95% CI: 0.000,0.104), difference in standing time (OR = 0.001, 95% CI: 0.000,0.742), and mean stride time (OR = 0.992, 95% CI:0.984,1.000) were identified as significant factors. The area under the ROC curve was 0.878 (95% CI: 0.805, 0.952), with a sensitivity of 0.935 and specificity of 0.726. The Brier score was 0.135, and the Hosmer-Lemeshow test (χ2 = 10.650, P = 0.222) indicated a good fit and calibration of the model.

CONCLUSION

The TGBT score, stride length, difference in standing time, and stride time are all protective factors associated with fall risk among the elderly. The developed risk prediction model demonstrates good discrimination and calibration, providing valuable insights for early screening and intervention in fall risk among older adults.

Brain modulation after exergaming training in advanced forms of Parkinson's disease: a randomized controlled study

BACKGROUND

Physical activity combined with virtual reality and exergaming has emerged as a new technique to improve engagement and provide clinical benefit for gait and balance disorders in people with Parkinson's disease (PD).

OBJECTIVE

To investigate the effects of a training protocol using a home-based exergaming system on brain volume and resting-state functional connectivity (rs-FC) in persons with PD.

METHODS

A single blind randomized controlled trial was conducted in people with PD with gait and/or balance disorders. The experimental (active) group performed 18 training sessions at home by playing a custom-designed exergame with full body movements, standing in front of a RGB-D Kinect® motion sensor, while the control group played using the computer keyboard. Both groups received the same training program. Clinical scales, gait recordings, and brain MRI were performed before and after training. We assessed the effects of both training on both the grey matter volumes (GVM) and rs-FC, within and between groups.

RESULTS

Twenty-three patients were enrolled and randomly assigned to either the active (n = 11) or control (n = 12) training groups. Comparing pre- to post-training, the active group showed significant improvements in gait and balance disorders, with decreased rs-FC between the sensorimotor, attentional and basal ganglia networks, but with an increase between the cerebellar and basal ganglia networks. In contrast, the control group showed no significant changes, and rs-FC significantly decreased in the mesolimbic and visuospatial cerebellar and basal ganglia networks. Post-training, the rs-FC was greater in the active relative to the control group between the basal ganglia, motor cortical and cerebellar areas, and bilaterally between the insula and the inferior temporal lobe. Conversely, rs FC was lower in the active relative to the control group between the pedunculopontine nucleus and cerebellar areas, between the temporal inferior lobes and the right thalamus, between the left putamen and dorsolateral prefrontal cortex, and within the default mode network.

CONCLUSIONS

Full-body movement training using a customized exergame induced brain rs-FC changes within the sensorimotor, attentional and cerebellar networks in people with PD. Further research is needed to comprehensively understand the neurophysiological effects of such training approaches. Trial registration ClinicalTrials.gov NCT03560089.

Alzheimer's Disease Related Biomarkers Were Associated with Amnestic Cognitive Impairment in Parkinson's Disease: A Cross-Sectional Cohort Study

BACKGROUND

Cognitive impairment is common in patients with Parkinson's disease (PD) and occurs through multiple mechanisms, including Alzheimer's disease (AD) pathology and the involvement of α-synucleinopathies. We aimed to investigate the pathological biomarkers of both PD and AD in plasma and neuronal extracellular vesicles (EVs) and their association with different types of cognitive impairment in PD patients.

METHODS

A total of 122 patients with PD and 30 healthy controls were included in this cross-sectional cohort study between March 2021 and July 2023. Non-dementia PD patients were divided into amnestic and non-amnestic groups according to the memory domain of a neuropsychological assessment. Plasma and neuronal EV biomarkers, including α-synuclein (α-syn), beta-amyloid (Aβ), total tau (T-tau), phosphorylated tau181 (p-tau181), and glial fibrillary acidic protein (GFAP), were measured using a single-molecule array and a chemiluminescence immunoassay, respectively.

RESULTS

Neuronal EV but not plasma α-syn levels, were significantly increased in PD as compared to healthy controls, and they were positively associated with UPDRS part III scores and the severity of cognitive impairment. A lower plasma Aβ42 level and higher neuronal EV T-tau level were found in the amnestic PD group compared to the non-amnestic PD group.

CONCLUSIONS

The results of the current study demonstrate that neuronal EV α-syn levels can be a sensitive biomarker for assisting in the diagnosis and disease severity prediction of PD. Both AD and PD pathologies are important factors in cognitive impairment associated with PD, and AD pathologies are more involved in amnestic memory deficit in PD.

A feature-aware multimodal framework with auto-fusion for Alzheimer's disease diagnosis

Alzheimer's disease (AD), one of the most common dementias, has about 4.6 million new cases yearly worldwide. Due to the significant amount of suspected AD patients, early screening for the disease has become particularly important. There are diversified types of AD diagnosis data, such as cognitive tests, images, and risk factors, many prior investigations have primarily concentrated on integrating only high-dimensional features and simple fusion concatenation, resulting in less-than-optimal outcomes for AD diagnosis. Therefore, We propose an enhanced multimodal AD diagnostic framework comprising a feature-aware module and an automatic model fusion strategy (AMFS). To preserve the correlation and significance features within a low-dimensional space, the feature-aware module employs a low-dimensional SHapley Additive exPlanation (SHAP) boosting feature selection as the initial step, following this analysis, diverse tiers of low-dimensional features are extracted from patients' biological data. Besides, in the high-dimensional stage, the feature-aware module integrates cross-modal attention mechanisms to capture subtle relationships among different cognitive domains, neuroimaging modalities, and risk factors. Subsequently, we integrate the aforementioned feature-aware module with graph convolutional networks (GCN) to address heterogeneous data in multimodal AD, while also possessing the capability to perceive relationships between different modalities. Lastly, our proposed AMFS autonomously learns optimal parameters for aligning two sub-models. The validation tests using two ADNI datasets show the high accuracies of 95.9% and 91.9% respectively, in AD diagnosis. The methods efficiently select features from multimodal AD data, optimizing model fusion for potential clinical assistance in diagnostics.

Validity of the Short Weekly Calendar Planning Activity in patients with Parkinson disease and nonmanifesting LRRK2 and GBA carriers

BACKGROUND AND PURPOSE

Subtle executive dysfunction is common in people newly diagnosed with Parkinson disease (PD), even when general cognitive abilities are intact. This study examined the Short Weekly Calendar Planning Activity (WCPA-10)'s known-group construct validity, comparing persons with PD to healthy controls (HCs) and nonmanifesting carriers of LRRK2 and GBA gene mutations to HCs. Additionally, convergent and ecological validity was examined.

METHODS

The study included 73 participants: 22 with idiopathic PD (iPD) who do not carry any of the founder GBA mutations or LRRK2-G2019S, 29 nonmanifesting carriers of the G2019S-LRRK2 (n = 14) and GBA (n = 15) mutations, and 22 HCs. Known-group validity was determined using the WCPA-10, convergent validity by also using the Montreal Cognitive Assessment (MoCA) and Color Trails Test (CTT), and ecological validity by using the WCPA-10, Schwab and England Activities of Daily Living Scale (SE ADL), and Physical Activity Scale for the Elderly (PASE).

RESULTS

Known-group validity of the WCPA-10 was established for the iPD group only; they followed fewer rules (p = 0.020), were slower (p = 0.003) and less efficient (p = 0.001), used more strategies (p = 0.017) on the WCPA-10, and achieved significantly lower CTT scores (p < 0.001) than the HCs. The nonmanifesting carriers and HCs were similar on all cognitive tests. Convergent and ecological validity of the WCPA-10 were partially established, with few correlations between WCPA-10 outcome measures and the MoCA (r = 0.50, r = 0.41), CTT-2 (r = 0.43), SE ADL (r = 0.41), and PASE (r = 0.54, r = 0.46, r = 0.31).

CONCLUSIONS

This study affirms the known-group validity for most (four) WCPA-10 scores and partially confirms its convergent and ecological validity for PD.

The lateralized effects of Parkinson's Disease on motor imagery: Evidence from mental chronometry

Alterations to the content of action representations may contribute to the movement challenges that characterize Parkinson's Disease (PD). One way to investigate action representations is through motor imagery. As PD motor symptoms typically have a unilateral onset, disease-related deficits related to action representations may follow a similarly lateralized pattern. The present study examined if temporal accuracy of motor imagery in individuals with PD differed according to the side of the body involved in the task. Thirty-eight participants with PD completed a mental chronometry task using their more affected and less affected side. Participants had significantly shorter mental versus physical movement times for the more affected. Higher imagery vividness in the kinaesthetic domain predicted shorter mental versus physical movement times for the more affected side, as did lower imagery vividness in the visual domain and poorer cognitive function. These results indicate that people with PD imagine movements differently when the target actions their more affected versus less affected side. It is additionally possible that side-specific deficits in the accurate processing of kinaesthetic information lead to an increased reliance on visual processes and cognitive resources to successfully execute motor imagery involving the more affected side.

Plasma biomarkers of neurodegeneration in patients and high risk subjects with Lewy body disease

Comorbid Alzheimer's disease (AD) neuropathology is common in Lewy body disease (LBD); however, AD comorbidity in the prodromal phase of LBD remains unclear. This study investigated AD comorbidity in the prodromal and symptomatic phases of LBD by analyzing plasma biomarkers in patients with Parkinson's disease (PD) and dementia with Lewy bodies (DLB) and individuals at risk of LBD (NaT-PROBE cohort). Patients with PD (PD group, n = 84) and DLB (DLB group, n = 16) and individuals with LBD with ≥ 2 (high-risk group, n = 82) and without (low-risk group, n = 37) prodromal symptoms were enrolled. Plasma amyloid-beta (Aβ) composite was measured using immunoprecipitation-mass spectrometry assays. Plasma phosphorylated tau 181 (p-tau181), neurofilament light chain (NfL), and alpha-synuclein (aSyn) were measured using a single-molecule array. Plasma p-tau181 levels were higher in the PD and DLB groups than in the low-risk group. Aβ composite level was higher in the DLB group than in the high-risk group. AD-related biomarker levels were not elevated in the high-risk group. NfL levels were higher in the high-risk, PD, and DLB groups than in the low-risk group. In the PD group, Aβ composite was associated with cognitive function, p-tau181 with motor function and non-motor symptoms, and NfL with cognitive and motor functions and non-motor symptoms. In the high-risk group, NfL was associated with metaiodobenzylguanidine scintigraphy abnormalities. The PD and DLB groups exhibited comorbid AD neuropathology, though not in the prodromal phase. Elevated plasma NfL levels, even without elevated AD-related plasma biomarker levels, may indicate aSyn-induced neurodegeneration in the LBD prodromal phase.