The impact of COVID-19 pandemic on patients with Huntington's disease and care-givers: A French survey.

Although the impact of the first wave of the COVID-19 pandemic on people with several neurological diseases has been largely investigated, little is available concerning people with Huntington's disease (HD). The main objective of the study was to interview people with HD and their caregivers in the Auvergne-Rhone Alpes region, France. The interview consisted of 16 items concerning general and medical information, and the impact of the first wave of COVID-19 pandemic on the medical care of people with HD and on their caregivers. The questionnaire was made available as online survey from October 1st, 2020 until November 15th, 2020. Fifty-two subjects participated (13 men, 39 women, mean age of 47.3 ± 15.5 years). Almost half participants (48%) experienced a worsening of pre-existing symptoms, with new-onset symptoms in the 44% of cases. The most frequent worsening was reported in gait and balance issues (67%), fatigue (58%), anxiety (50%), and depression (50%). The 70.8% of participants reported an inappropriate overall care of HD due to long delays to access medical care (30%) and other health care teams (60%). More than half of the participants (54.2%) reported that the COVID-19 pandemic had a negative impact on their caregiver/family. Our findings emphasize the negative impact of the first wave of COVID-19 pandemic on the healthcare of HD population and their caregivers. Not only some symptoms were aggravated, but new symptoms appeared during the pandemic. In the future, health policies should be considered to improve the care of patients with rare diseases such as HD.

Disentangling Bradykinesia and Rigidity in Parkinson's Disease: Evidence from Short- and Long-Term Subthalamic Nucleus Deep Brain Stimulation.

OBJECTIVE: Bradykinesia and rigidity are considered closely related motor signs in Parkinson disease (PD), but recent neurophysiological findings suggest distinct pathophysiological mechanisms. This study aims to examine and compare longitudinal changes in bradykinesia and rigidity in PD patients treated with bilateral subthalamic nucleus deep brain stimulation (STN-DBS). METHODS: In this retrospective cohort study, the clinical progression of appendicular and axial bradykinesia and rigidity was assessed up to 15 years after STN-DBS in the best treatment conditions (ON medication and ON stimulation). The severity of bradykinesia and rigidity was examined using ad hoc composite scores from specific subitems of the Unified Parkinson's Disease Rating Scale motor part (UPDRS-III). Short- and long-term predictors of bradykinesia and rigidity were analyzed through linear regression analysis, considering various preoperative demographic and clinical data, including disease duration and severity, phenotype, motor and cognitive scores (eg, frontal score), and medication. RESULTS: A total of 301 patients were examined before and 1 year after surgery. Among them, 101 and 56 individuals were also evaluated at 10-year and 15-year follow-ups, respectively. Bradykinesia significantly worsened after surgery, especially in appendicular segments (p < 0.001). Conversely, rigidity showed sustained benefit, with unchanged clinical scores compared to preoperative assessment (p > 0.05). Preoperative motor disability (eg, composite scores from the UPDRS-III) predicted short- and long-term outcomes for both bradykinesia and rigidity (p < 0.01). Executive dysfunction was specifically linked to bradykinesia but not to rigidity (p < 0.05). INTERPRETATION: Bradykinesia and rigidity show long-term divergent progression in PD following STN-DBS and are associated with independent clinical factors, supporting the hypothesis of partially distinct pathophysiology. ANN NEUROL 2024;96:234-246.

Spatiotemporal Gait Differences before and after Botulinum Toxin in People with Focal Dystonia: A Pilot Study.

BACKGROUND: The impact of focal dystonia on gait has attracted little attention and remains elusive. Considering the importance of both visual and head control in gait, blepharospasm and cervical dystonia should affect gait. Improvement of cervical/eyelid control following botulinum toxin (BTX) injections would translate into gait changes. OBJECTIVES: To assess gait differences in people with focal dystonia before and after BTX treatment. METHODS: Ten patients with blepharospasm, 10 patients with cervical dystonia, and 20 healthy age- and gender-matched controls were included. Gait was assessed before and 1-month after BTX injections using Biodex Gait Trainer™ 3. Gait velocity, cadence, step length, step asymmetry, and variability of step length were compared between patients and controls, and between the two time-points using non-parametric statistics. RESULTS: At baseline, compared to controls, cervical dystonia patients showed reduced gait velocity, step length, and cadence. After BTX injections, while gait velocity and step length were significantly increased and step length variability reduced, gait parameters still differed between patients and controls. In blepharospasm patients, baseline gait velocity and step length were significantly smaller than in controls. After BTX injections, these gait parameters were significantly increased and variability decreased, so that patients no longer differed from controls. CONCLUSION: Gait differences exist between patients with focal dystonia not directly affecting the lower limbs and healthy controls. These gait abnormalities were improved differently by BTX treatment according to the type of dystonia. These disparities suggest different pathophysiological mechanisms and support the need for changes in rehabilitation routines in cervical dystonia.

Efficacy and safety of clonidine for the treatment of impulse control disorder in Parkinson's disease: a multicenter, parallel, randomised, double-blind, Phase 2b Clinical trial.

BACKGROUND: Impulse control disorders (ICDs) are frequently encountered in Parkinson's disease (PD). OBJECTIVES: We aimed to assess whether clonidine, an α2-adrenergic receptor agonist, would improve ICDs. METHODS: We conducted a multicentre trial in five movement disorder departments. Patients with PD and ICDs (n = 41) were enrolled in an 8-week, randomised (1:1), double-blind, placebo-controlled study of clonidine (75 µg twice a day). Randomisation and allocation to the trial group were carried out by a central computer system. The primary outcome was the change at 8 weeks in symptom severity using the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease-Rating Scale (QUIP-RS) score. A reduction of the most elevated subscore of the QUIP-RS of more than 3 points without any increase in the other QUIP-RS dimension defined success. RESULTS: Between 15 May 2019 and 10 September 2021, 19 patients in the clonidine group and 20 patients in the placebo group were enrolled. The proportion difference of success in reducing QUIP-RS at 8 weeks, was 7% (one-sided upper 90% CI 27%) with 42.1% of success in the clonidine group and 35.0% in the placebo group. Compared to patients in the placebo group, patients in the clonidine group experienced a greater reduction in the total QUIP-RS score at 8 weeks (11.0 points vs. 3.6). DISCUSSION: Clonidine was well tolerated but our study was not enough powerful to demonstrate significant superiority compared to placebo in reducing ICDs despite a greater reduction of total QUIP score at 8 weeks. A phase 3 study should be conducted. TRIAL REGISTRATION: The study was registered (NCT03552068) on clinicaltrials.gov on June 11, 2018.

Multi-scale and cross-dimensional TMS mapping: A proof of principle in patients with Parkinson's disease and deep brain stimulation.

Introduction: Transcranial magnetic stimulation (TMS) mapping has become a critical tool for exploratory studies of the human corticomotor (M1) organization. Here, we propose to gather existing cutting-edge TMS-EMG and TMS-EEG approaches into a combined multi-dimensional TMS mapping that considers local and whole-brain excitability changes as well as state and time-specific changes in cortical activity. We applied this multi-dimensional TMS mapping approach to patients with Parkinson's disease (PD) with Deep brain stimulation (DBS) of the sub-thalamic nucleus (STN) ON and OFF. Our goal was to identifying one or several TMS mapping-derived markers that could provide unprecedent new insights onto the mechanisms of DBS in movement disorders. Methods: Six PD patients (1 female, mean age: 62.5 yo [59-65]) implanted with DBS-STN for 1 year, underwent a robotized sulcus-shaped TMS motor mapping to measure changes in muscle-specific corticomotor representations and a movement initiation task to probe state-dependent modulations of corticospinal excitability in the ON (using clinically relevant DBS parameters) and OFF DBS states. Cortical excitability and evoked dynamics of three cortical areas involved in the neural control of voluntary movements (M1, pre-supplementary motor area - preSMA and inferior frontal gyrus - IFG) were then mapped using TMS-EEG coupling in the ON and OFF state. Lastly, we investigated the timing and nature of the STN-to-M1 inputs using a paired pulse DBS-TMS-EEG protocol. Results: In our sample of patients, DBS appeared to induce fast within-area somatotopic re-arrangements of motor finger representations in M1, as revealed by mediolateral shifts of corticomuscle representations. STN-DBS improved reaction times while up-regulating corticospinal excitability, especially during endogenous motor preparation. Evoked dynamics revealed marked increases in inhibitory circuits in the IFG and M1 with DBS ON. Finally, inhibitory conditioning effects of STN single pulses on corticomotor activity were found at timings relevant for the activation of inhibitory GABAergic receptors (4 and 20 ms). Conclusion: Taken together, these results suggest a predominant role of some markers in explaining beneficial DBS effects, such as a context-dependent modulation of corticospinal excitability and the recruitment of distinct inhibitory circuits, involving long-range projections from higher level motor centers and local GABAergic neuronal populations. These combined measures might help to identify discriminative features of DBS mechanisms towards deep clinical phenotyping of DBS effects in Parkinson's Disease and in other pathological conditions.

Long-term effects of bilateral subthalamic nucleus deep brain stimulation on gait disorders in Parkinson's disease: a clinical-instrumental study.

OBJECTIVE: To assess the long-term effects of bilateral subthalamic nucleus deep brain stimulation (STN-DBS) on gait in a cohort of advanced Parkinson's Disease (PD) patients. METHODS: This observational study included consecutive PD patients treated with bilateral STN-DBS. Different stimulation and drug treatment conditions were assessed: on-stimulation/off-medication, off-stimulation/off-medication, and on-stimulation/on-medication. Each patient performed the instrumented Timed Up and Go test (iTUG). The instrumental evaluation of walking ability was carried out with a wearable inertial sensor containing a three-dimensional (3D) accelerometer, gyroscope, and magnetometer. This device could provide 3D linear acceleration, angular velocity, and magnetic field vector. Disease motor severity was evaluated with the total score and subscores of the Unified Parkinson Disease Rating Scale part III. RESULTS: Twenty-five PD patients with a 5-years median follow-up after surgery (range 3-7) were included (18 men; mean disease duration at surgery 10.44 ± 4.62 years; mean age at surgery 58.40 ± 5.73 years). Both stimulation and medication reduced the total duration of the iTUG and most of its different phases, suggesting a long-term beneficial effect on gait after surgery. However, comparing the two treatments, dopaminergic therapy had a more marked effect in all test phases. STN-DBS alone reduced total iTUG duration, sit-to-stand, and second turn phases duration, while it had a lower effect on stand-to-sit, first turn, forward walking, and walking backward phases duration. CONCLUSIONS: This study highlighted that in the long-term after surgery, STN-DBS may contribute to gait and postural control improvement when used together with dopamine replacement therapy, which still shows a substantial beneficial effect.

Interplay between speech and gait variables in Parkinson's disease patients treated with subthalamic nucleus deep brain stimulation: A long-term instrumental assessment.

OBJECTIVE: To evaluate correlations between speech and gait parameters in the long term and under different medication and subthalamic nucleus deep brain stimulation (STN-DBS) conditions in a cohort of advanced Parkinson's disease (PD) patients. METHODS: This observational study included consecutive PD patients treated with bilateral STN-DBS. Axial symptoms were evaluated using a standardized clinical-instrumental approach. Speech and gait were assessed by perceptual and acoustic analyses and by the instrumented Timed Up and Go (iTUG) test, respectively. Disease motor severity was evaluated with the total score and subscores of the Unified Parkinson's Disease Rating Scale (UPDRS) Part III. Different stimulation and drug treatment conditions were assessed: on-stimulation/off-medication, off-stimulation/off-medication, and on-stimulation/on-medication. RESULTS: Twenty-five PD patients with a 5-year median follow-up after surgery (range 3-7 years) were included (18 males; disease duration at surgery: 10.44 [SD 4.62] years; age at surgery: 58.40 [SD 5.73] years). In the off-stimulation/off-medication and on-stimulation/on-medication conditions, patients who spoke louder had also the greater acceleration of the trunk during gait; whereas in the on-stimulation/on-medication condition only, patients with the poorer voice quality were also the worst to perform the sit to stand and gait phases of the iTUG. Conversely, patients with the higher speech rate performed well in the turning and walking phases of the iTUG. CONCLUSIONS: This study underlines the presence of different correlations between treatment effects of speech and gait parameters in PD patients treated with bilateral STN-DBS. This may allow us to better understand the common pathophysiological basis of these alterations and to develop a more specific and tailored rehabilitation approach for axial signs after surgery.

Comparative features and outcomes of major neurological complications of COVID-19.

BACKGROUND AND PURPOSE: The aim of this study was to assess the neurological complications of SARS-CoV-2 infection and compare phenotypes and outcomes in infected patients with and without selected neurological manifestations. METHODS: The data source was a registry established by the European Academy of Neurology during the first wave of the COVID-19 pandemic. Neurologists collected data on patients with COVID-19 seen as in- and outpatients and in emergency rooms in 23 European and seven non-European countries. Prospective and retrospective data included patient demographics, lifestyle habits, comorbidities, main COVID-19 complications, hospital and intensive care unit admissions, diagnostic tests, and outcome. Acute/subacute selected neurological manifestations in patients with COVID-19 were analysed, comparing individuals with and without each condition for several risk factors. RESULTS: By July 31, 2021, 1523 patients (758 men, 756 women, and nine intersex/unknown, aged 16-101 years) were registered. Neurological manifestations were diagnosed in 1213 infected patients (79.6%). At study entry, 978 patients (64.2%) had one or more chronic general or neurological comorbidities. Predominant acute/subacute neurological manifestations were cognitive dysfunction (N = 449, 29.5%), stroke (N = 392, 25.7%), sleep-wake disturbances (N = 250, 16.4%), dysautonomia (N = 224, 14.7%), peripheral neuropathy (N = 145, 9.5%), movement disorders (N = 142, 9.3%), ataxia (N = 134, 8.8%), and seizures (N = 126, 8.3%). These manifestations tended to differ with regard to age, general and neurological comorbidities, infection severity and non-neurological manifestations, extent of association with other acute/subacute neurological manifestations, and outcome. CONCLUSIONS: Patients with COVID-19 and neurological manifestations present with distinct phenotypes. Differences in age, general and neurological comorbidities, and infection severity characterize the various neurological manifestations of COVID-19.

Pallidal and Cortical Oscillations in Freely Moving Patients With Dystonia.

OBJECTIVES: To evaluate the correlation between the pallidal local field potentials (LFPs) activity and the cortical oscillations (at rest and during several motor tasks) in two freely moving patients with generalized dystonia and pallidal deep brain stimulation (DBS). MATERIALS AND METHODS: Two women with isolated generalized dystonia were selected for bilateral globus pallidus internus (GPi) DBS. After the electrodes' implantation, cortical activity was recorded by a portable electroencephalography (EEG) system simultaneously with GPi LFPs activity, during several motor tasks, gait, and rest condition. Recordings were not performed during stimulation. EEG and LFPs signals relative to each specific movement were coupled together and grouped in neck/upper limbs movements and gait. Power spectral density (PSD), EEG-LFP coherence (through envelope of imaginary coherence operator), and 1/f exponent of LFP-PSD background were calculated. RESULTS: In both patients, the pallidal LFPs PSD at rest was characterized by prominent 4-12 Hz activity. Voluntary movements increased activity in the theta (θ) band (4-7 Hz) compared to rest, in both LFPs and EEG signals. Gait induced a drastic raise of θ activity in both patients' pallidal activity, less marked for the EEG signal. A coherence peak within the 8-13 Hz range was found between pallidal LFPs and EEG recorded at rest. CONCLUSIONS: Neck/upper limbs voluntary movements and gait suppressed the GPi-LFPs-cortical-EEG coherence and differently impacted both EEG and LFPs low frequency activity. These findings suggest a selective modulation of the cortico-basal ganglia network activity in dystonia.

ACTB gene mutation in combined Dystonia-Deafness syndrome with parkinsonism: Expanding the phenotype and highlighting the long-term GPi DBS outcome.

We report a Dystonia-Deafness syndrome patient treated by pallidal Deep Brain Stimulation with significant long-term benefits. Our study expands and confirms the complex phenotypic spectrum of ACTB gene-related disorders and supports the effectiveness of pallidal stimulation on motor outcomes and quality of life in dystonia due to ACTB p.Arg183Trp heterozygosity.

Axial impairment and falls in Parkinson's disease: 15 years of subthalamic deep brain stimulation.

In this retrospective study, we longitudinally analyzed axial impairment and falls in people with Parkinson's disease (PD) and subthalamic nucleus deep brain stimulation (STN-DBS). Axial scores and falling frequency were examined at baseline, and 1, 10, and 15 years after surgery. Preoperative demographic and clinical data, including PD duration and severity, phenotype, motor and cognitive scales, medications, and vascular changes on neuroimaging were examined as possible risk factors through Kaplan-Meier and Cox regression analyses. Of 302 individuals examined before and at 1 year after surgery, 102 and 57 were available also at 10 and 15 years of follow-up, respectively. Axial scores were similar at baseline and at 1 year but worsened at 10 and 15 years. The prevalence rate of frequent fallers progressively increased from baseline to 15 years. Preoperative axial scores, frontal dysfunction and age at PD onset were risk factors for axial impairment progression after surgery. Axial scores, akinetic/rigid phenotype, age at disease onset and disease duration at surgery predicted frequent falls. Overall, axial signs progressively worsened over the long-term period following STN-DBS, likely related to the progression of PD, especially in a subgroup of subjects with specific risk factors.

COVID-19 and Parkinsonism: A Critical Appraisal.

A few cases of parkinsonism linked to COVID-19 infection have been reported so far, raising the possibility of a post-viral parkinsonian syndrome. The objective of this review is to summarize the clinical, biological, and neuroimaging features of published cases describing COVID-19-related parkinsonism and to discuss the possible pathophysiological mechanisms. A comprehensive literature search was performed using NCBI's PubMed database and standardized search terms. Thirteen cases of COVID-19-related parkinsonism were included (7 males; mean age: 51 years ± 14.51, range 31-73). Patients were classified based on the possible mechanisms of post-COVID-19 parkinsonism: extensive inflammation or hypoxic brain injury within the context of encephalopathy (n = 5); unmasking of underlying still non-symptomatic Parkinson's Disease (PD) (n = 5), and structural and functional basal ganglia damage (n = 3). The various clinical scenarios show different outcomes and responses to dopaminergic treatment. Different mechanisms may play a role, including vascular damage, neuroinflammation, SARS-CoV-2 neuroinvasive potential, and the impact of SARS-CoV-2 on α-synuclein. Our results confirm that the appearance of parkinsonism during or immediately after COVID-19 infection represents a very rare event. Future long-term observational studies are needed to evaluate the possible role of SARS-CoV-2 infection as a trigger for the development of PD in the long term.

Does Motor Symptoms Asymmetry Predict Motor Outcome of Subthalamic Deep Brain Stimulation in Parkinson's Disease Patients?

Background: In Parkinson's disease (PD), the side of motor symptoms onset may influence disease progression, with a faster motor symptom progression in patients with left side lateralization. Moreover, worse neuropsychological outcomes after subthalamic nucleus deep brain stimulation (STN-DBS) have been described in patients with predominantly left-sided motor symptoms. The objective of this study was to evaluate if the body side of motor symptoms onset may predict motor outcome of bilateral STN-DBS. Methods: This retrospective study included all consecutive PD patients treated with bilateral STN-DBS at Grenoble University Hospital from 1993 to 2015. Demographic, clinical and neuroimaging data were collected before (baseline condition) and 1 year after surgery (follow-up condition). The predictive factors of motor outcome at one-year follow-up, measured by the percentage change in the MDS-UPDRS-III score, were evaluated through univariate and multivariate linear regression analysis. Results: A total of 233 patients were included with one-year follow-up after surgery [143 males (61.40%); 121 (51.90 %) right body onset; 112 (48.10%) left body onset; mean age at surgery, 55.31 ± 8.44 years; mean disease duration, 11.61 ± 3.87]. Multivariate linear regression analysis showed that the left side of motor symptoms onset did not predict motor outcome (ß = 0.093, 95% CI = -1.967 to 11.497, p = 0.164). Conclusions: In this retrospective study, the body side of motor symptoms onset did not significantly influence the one-year motor outcome in a large cohort of PD patients treated with bilateral STN-DBS.

Advances in DBS Technology and Novel Applications: Focus on Movement Disorders.

PURPOSE OF REVIEW: Deep brain stimulation (DBS) is an established treatment in several movement disorders, including Parkinson's disease, dystonia, tremor, and Tourette syndrome. In this review, we will review and discuss the most recent findings including but not limited to clinical evidence. RECENT FINDINGS: New DBS technologies include novel hardware design (electrodes, cables, implanted pulse generators) enabling new stimulation patterns and adaptive DBS which delivers potential stimulation tailored to moment-to-moment changes in the patient's condition. Better understanding of movement disorders pathophysiology and functional anatomy has been pivotal for studying the effects of DBS on the mesencephalic locomotor region, the nucleus basalis of Meynert, the substantia nigra, and the spinal cord. Eventually, neurosurgical practice has improved with more accurate target visualization or combined targeting. A rising research domain emphasizes bridging neuromodulation and neuroprotection. Recent advances in DBS therapy bring more possibilities to effectively treat people with movement disorders. Future research would focus on improving adaptive DBS, leading more clinical trials on novel targets, and exploring neuromodulation effects on neuroprotection.

Long-term independence and quality of life after subthalamic stimulation in Parkinson disease.

BACKGROUND AND PURPOSE: Studies on long-term nonmotor outcomes of subthalamic nucleus stimulation in Parkinson disease (PD) are scarce. This study reports on very long-term non-motor and motor outcomes in one of the largest cohorts of people with advanced PD, treated for >10 years with subthalamic nucleus stimulation. The main outcome was to document the evolution of independence in activities of daily living. The secondary outcomes were to measure the change in quality of life, as well as non-motor and motor outcomes. METHODS: Patients were studied preoperatively, at 1 year, and beyond 10 years after subthalamic stimulation with an established protocol including motor, non-motor, and neuropsychological assessments. RESULTS: Eighty-five people with PD were included. Independence scores in the off-medication condition (measured with the Schwab & England Activities of Daily Living Scale) as well as quality of life (measured with the Parkinson's Disease Questionnaire [PDQ]-37) remained improved at longest follow-up compared to preoperatively (respectively, p < 0.001, p = 0.015). Cognitive scores, measured with the Mattis Dementia Rating Scale, significantly worsened compared to before and 1 year after surgery (p < 0.001), without significant change in depression, measured with the Beck Depression Inventory. Motor fluctuations, dyskinesias, and off dystonia remained improved at longest follow-up (p < 0.001), with a significant reduction in dopaminergic treatment (45%, p < 0.001). CONCLUSIONS: This study highlights the long-term improvement of subthalamic stimulation on independence and quality of life, despite the progression of disease and the occurrence of levodopa-resistant symptoms.

Early Parkinson's Disease Phenotypes Tailored by Personality, Behavior, and Motor Symptoms.

BACKGROUND: Previous studies described a parkinsonian personality characterized as rigid, introverted, and cautious; however, little is known about personality traits in de novo Parkinson's disease (PD) patients and their relationships with motor and neuropsychiatric symptoms. OBJECTIVE: To investigate personality in de novo PD and explore its relationship with PD symptoms. METHODS: Using Cloninger's biosocial model, we assessed personality in 193 de novo PD patients. Motor and non-motor symptoms were measured using several validated scales. Cluster analysis was conducted to investigate the interrelationship of personality traits, motor, and non-motor symptoms. RESULTS: PD patients showed low novelty seeking, high harm avoidance, and normal reward dependence and persistence scores. Harm avoidance was positively correlated with the severity of depression, anxiety, and apathy (rs = [0.435, 0.676], p < 0.001) and negatively correlated with quality of life (rs = -0.492, p < 0.001). Novelty seeking, reward dependence, and persistence were negatively correlated with apathy (rs = [-0.274, -0.375], p < 0.001). Classification of patients according to personality and PD symptoms revealed 3 distinct clusters: i) neuropsychiatric phenotype (with high harm avoidance and low novelty seeking, hypodopaminergic neuropsychiatric symptoms and higher impulsivity), ii) motor phenotype (with low novelty seeking and higher motor severity), iii) benign phenotype (with low harm avoidance and high novelty seeking, reward dependence, and persistence traits clustered with lower symptoms severity and low impulsivity). CONCLUSION: Personality in early PD patients allows us to recognize 3 patients' phenotypes. Identification of such subgroups may help to better understand their natural history. Their longitudinal follow-up will allow confirming whether some personality features might influence disease evolution and treatment.

Subtle anomaly detection: Application to brain MRI analysis of de novo Parkinsonian patients.

With the advent of recent deep learning techniques, computerized methods for automatic lesion segmentation have reached performances comparable to those of medical practitioners. However, little attention has been paid to the detection of subtle physiological changes caused by evolutive pathologies, such as neurodegenerative diseases. In this work, we leverage deep learning models to detect anomalies in brain diffusion tensor imaging (DTI) parameter maps of recently diagnosed and untreated (de novo) patients with Parkinson's disease (PD). For this purpose, we trained auto-encoders on parameter maps of healthy controls (n = 56) and tested them on those of de novo PD patients (n = 129). We considered large reconstruction errors between the original and reconstructed images to be anomalies that, when quantified, allow discerning between de novo PD patients and healthy controls. The most discriminating brain macro-region was found to be the white matter with a ROC-AUC 68.3 (IQR 5.4) and the best subcortical structure, the GPi (ROC-AUC 62.6 IQR 5.4). Our results indicate that our deep learning-based model can detect potentially pathological regions in de novo PD patients, without requiring any expert delineation. This may enable extracting neuroimaging biomarkers of PD in the future, but further testing on larger cohorts is needed. Such models can be seamlessly extended with additional parameter maps and applied to study the physio-pathology of other neurological diseases.

Limbic Serotonergic Plasticity Contributes to the Compensation of Apathy in Early Parkinson's Disease.

BACKGROUND: De novo Parkinson's disease (PD) patients with apathy exhibit prominent limbic serotonergic dysfunction and microstructural disarray. Whether this distinctive lesion profile at diagnosis entails different prognosis remains unknown. OBJECTIVES: To investigate the progression of dopaminergic and serotonergic dysfunction and their relation to motor and nonmotor impairment in PD patients with or without apathy at diagnosis. METHODS: Thirteen de novo apathetic and 13 nonapathetic PD patients were recruited in a longitudinal double-tracer positron emission tomography cohort study. We quantified the progression of presynaptic dopaminergic and serotonergic pathology using [11 C]PE2I for dopamine transporter and [11 C]DASB for serotonin transporter at baseline and 3 to 5 years later, using linear mixed-effect models and mediation analysis to compare the longitudinal evolution between groups for clinical impairment and region-of-interest-based analysis. RESULTS: After the initiation of dopamine replacement therapy, apathy, depression, and anxiety improved at follow-up in patients with apathy at diagnosis (n = 10) to the level of patients without apathy (n = 11). Patients had similar progression of motor impairment, whereas mild impulsive behaviors developed in both groups. Striato-pallidal and mesocorticolimbic presynaptic dopaminergic loss progressed similarly in both groups, as did serotonergic pathology in the putamen, caudate nucleus, and pallidum. Contrastingly, serotonergic innervation selectively increased in the ventral striatum and anterior cingulate cortex in apathetic patients, contributing to the reversal of apathy besides dopamine replacement therapy. CONCLUSION: Patients suffering from apathy at diagnosis exhibit compensatory changes in limbic serotonergic innervation within 5 years of diagnosis, with promising evidence that serotonergic plasticity contributes to the reversal of apathy. The relationship between serotonergic plasticity and dopaminergic treatments warrants further longitudinal investigations. © 2022 International Parkinson and Movement Disorder Society.

Short- and long-term outcome and predictors in an international cohort of patients with neuro-COVID-19.

BACKGROUND AND PURPOSE: Despite the increasing number of reports on the spectrum of neurological manifestations of COVID-19 (neuro-COVID), few studies have assessed short- and long-term outcome of the disease. METHODS: This is a cohort study enrolling adult patients with neuro-COVID seen in neurological consultation. Data were collected prospectively or retrospectively in the European Academy of Neurology NEuro-covid ReGistrY ((ENERGY). The outcome at discharge was measured using the modified Rankin Scale and defined as 'stable/improved' if the modified Rankin Scale score was equal to or lower than the pre-morbid score, 'worse' if the score was higher than the pre-morbid score. Status at 6 months was also recorded. Demographic and clinical variables were assessed as predictors of outcome at discharge and 6 months. RESULTS: From July 2020 to March 2021, 971 patients from 19 countries were included. 810 (83.4%) were hospitalized. 432 (53.3%) were discharged with worse functional status. Older age, stupor/coma, stroke and intensive care unit (ICU) admission were predictors of worse outcome at discharge. 132 (16.3%) died in hospital. Older age, cancer, cardiovascular complications, refractory shock, stupor/coma and ICU admission were associated with death. 262 were followed for 6 months. Acute stroke or ataxia, ICU admission and degree of functional impairment at discharge were predictors of worse outcome. 65/221 hospitalized patients (29.4%) and 10/32 non-hospitalized patients (24.4%) experienced persisting neurological symptoms/signs. 10/262 patients (3.8%) developed new neurological complaints during the 6 months of follow-up. CONCLUSIONS: Neuro-COVID is a severe disease associated with worse functional status at discharge, particularly in older subjects and those with comorbidities and acute complications of infection.

Do neuropsychiatric fluctuations temporally match motor fluctuations in Parkinson's disease?

INTRODUCTION: In Parkinson's disease (PD), non-motor fluctuations (NMFs), especially neuropsychiatric fluctuations, often coexist with motor fluctuations (MFs) but are often under-recognized by physicians and patients. OBJECTIVE: To investigate the relationship between MFs and neuropsychiatric fluctuations in PD. METHODS: PD patients with MFs and NMFs were enrolled. The Parkinson's Kinetigraph (PKG), a wearable device to detect MFs and dyskinesia, was used to confirm and measure MFs. The Neuropsychiatric Fluctuation Scale (NFS), a scale composed by subscores for both the ON and OFF neuropsychiatric states, was used to identify and quantify neuropsychiatric fluctuations. Patients were asked to wear the PKG for six consecutive days to identify the ON and OFF motor periods, and then to fill the NFS during the ON and OFF motor periods for three consecutive days wearing the PKG. The PKG system provided a bradykinesia score (BKS) and a dyskinesia score (DKS). Relations between BKS, DKS, and ON and OFF NFS subscores were analyzed. RESULTS: In 18 PD patients, anxiety, apathy, and depression characterized the OFF condition, whereas self-confidence, competency, and interest in doing things were typically in the ON condition. There was a positive correlation between the BKS and the OFF NFS subscores (p = 0.036, r = 0.51), whereas no correlation was found between the DKS and the ON NFS subscores (p = 0.38, r = 0.22). CONCLUSION: Neuropsychiatric fluctuations temporarily matched the OFF MFs only in the OFF condition. These findings are useful to better manage OFF NMSs and support the need to further investigate associations between non-motor and motor symptoms in PD patients.