Response to the letter "Reassessing the hypothesis of essential tremor as a prodromal feature of Parkinson's disease".

There is growing body of evidence that some patients with essential tremor (ET) have an increased risk for developing Parkinson's disease (PD) and, therefore, as noted in our paper, ET may be considered a prodromal feature of PD. Although a genetic causal link between ET and PD has not been established, future development of diagnostic and progression biomarkers may provide insight into the relationship between these common movement disorders.

Establishing a MoCA cut-off point for cognitive impairment detection in Mexican people living with Parkinson's disease: A comprehensive assessment (level II) approach.

Background: Cognitive impairment (CI) is a prevalent and debilitating non-motor symptom of Parkinson's disease (PD), affecting around 25-30 % of the people living with PD (PwP). The Montreal Cognitive Assessment (MoCA) is a widely used tool for detecting CI. Yet, its optimal cut-off score for PwP, particularly within specific populations such as the Mexican demographic, remains inadequately defined.

Montreal cognitive assessment as a cognitive outcome measure in progressive supranuclear palsy.

Background: The Montreal Cognitive assessment (MoCA) is a well-validated global cognitive screening instrument. Its validity in progressive supranuclear palsy (PSP) has not been assessed.

Objectives: To evaluate the MoCA as an outcome measure in PSP clinical trials.

Clinical characteristics of the Ala21Val variant in the myelin proteolipid protein 1 (PLP1) gene associated with Pelizaeus-Merzbacher disease in a Brazilian male patient.

Here, we report the case of a 29-year-old male with classic Pelizaeus-Merzbacher disease (PMD) harboring the PLP1 variant NM_000533.5:c.62 C > T, leading to an NP_000524.

Fox Insight: Most Bothersome Symptoms in Early-Stage Parkinson's Disease.

Background: Limited evidence exists regarding the meaningfulness of symptoms experienced in early Parkinson's disease (PD).

Objectives: To identify the most bothersome symptoms experienced by people with early PD, leveraging data from the Parkinson's Disease Patient Report of Problems (PD-PROP) questionnaire within the Fox Insight Study.

Methods: Individuals with a self-reported diagnosis of PD completed the PD-PROP questionnaire, reporting up to five most bothersome symptoms.

Factor analysis and clustering of motor and psychiatric dimensions in idiopathic blepharospasm.

Introduction: Idiopathic blepharospasm is a clinically heterogeneous form of focal dystonia, also associated with psychiatric symptoms. The identification of the most relevant sets of motor and psychiatric manifestations may help better understand the specific phenomenology of the condition and delineate blepharospasm subtypes more accurately.

Methods: Patients with idiopathic blepharospasm were from the Dystonia Coalition project.

Challenges in Describing Tremor and Dystonia.

Tremor is defined as an oscillatory and rhythmical movement. By contrast, dystonia is defined by sustained or intermittent abnormal postures, repetitive movements, or both. Tremor and dystonia often coexist in the same individual.

The limbic and extra-limbic encephalitis associated with glutamic acid decarboxylase (GAD)-65 antibodies: an observational study.

We aimed to define the clinical features and outcomes of encephalitis associated with anti-GAD65 Abs. In addition, we reviewed cases published in the literature with GAD65 encephalitis. We retrospectively studied 482 consecutive patients attending a tertiary care center for evaluation of an autoimmune neurological disorder.

Multimodal oculomotor assessment reveals prodromal markers of Parkinson's disease in non-manifesting LRRK2 G2019S mutation carriers.

Oculomotor behaviour changes in patients with Parkinson's disease (PD) are a promising source of prodromal disease markers. Capitalizing on this phenomenon to facilitate early diagnosis requires oculomotor assessment in prodromal cohorts. We examined oculomotor behaviour in non-manifesting LRRK2 G2019S mutation carriers (LRRK2-NM), who have heightened PD risk.

Current concepts and molecular pathology of neurodegenerative diseases.

Neurodegenerative diseases are a pathologically, clinically and genetically diverse group of diseases characterised by selective dysfunction, loss of synaptic connectivity and neurodegeneration, ​and are associated with the deposition of misfolded proteins in neurons and/or glia. Molecular studies have highlighted the role of conformationally altered proteins in the pathogenesis of neurodegenerative diseases and have paved the way for developing disease-specific biomarkers that capture and differentiate the main type/s of protein abnormality responsible for neurodegenerative diseases, some of which are currently used in clinical practice. These proteins follow sequential patterns of anatomical involvement and disease spread in the brain and may also be detected in peripheral organs.

Closed-loop systems for deep brain stimulation to treat neuropsychiatric disorders.

Introduction: A closed-loop or feedback-control system is a process which considers the system's output in order to automatically adjust the input. Compared to a traditional open-loop system, a closed-loop system allows for a higher degree of accuracy with minimal human intervention. Novel methods of closed loop 'adaptive' deep brain stimulation DBS (aDBS) are being developed.

Clinical Outcome Assessments for Spasticity: Review, Critique, and Recommendations.

Background: Spasticity is a common feature in patients with disruptions in corticospinal pathways. However, the term is used ambiguously. Here, spasticity is defined as enhanced velocity-dependent stretch reflexes and placed within the context of deforming spastic paresis encompassing other forms of muscle overactivity.

Progressive Supranuclear Palsy in India: Past, Present, and Future.

Progressive supranuclear palsy (PSP) has emerged as a key area of interest among researchers worldwide, including those in India, who have actively studied the disorder over the past several decades. This review meticulously explores the extensive range of Indian research on PSP up to the present and offers insights into both current initiatives and potential future directions for managing PSP within the region. Historical research contributions have spanned 80 publications from 1974 to 2023, encompassing diverse themes from clinical phenotyping and historical analysis to isolated investigative studies and therapeutic trials.

Rare Spinocerebellar Ataxia Types in Canada: A Case Series and Review of the Literature.

Background: There is limited information on rare spinocerebellar ataxia (SCA) variants, particularly in the Canadian population. This study aimed to describe the demographic and clinical features of uncommon SCA subtypes in Canada and compare them with international data.

Methods: We conducted a case series and literature review of adult patients with rare SCA subtypes, including SCA5, SCA7, SCA12, SCA14, SCA15, SCA28, SCA34, SCA35 and SCA36.

Adult Phenotype of -Associated Disorders.

Background And Objectives: Pathogenic variants are associated with neurodevelopmental disorders and developmental and epileptic encephalopathy. While pediatric phenotypes have been readily explored, adult phenotypes are not well understood. We aimed to investigate the phenotypic spectrum of adult patients with variants.

Risk of fall with device-based advanced treatments in Parkinson's disease: a systematic review and network meta-analysis.

Background: Deep brain stimulation (DBS) and infusion therapies are effective treatments for the motor complications of Parkinson's disease (PD), but less established is their role in fall prevention. This systematic review and network meta-analysis (NMA) aimed to evaluate the risk of falls associated with advanced therapies in PD.

Methods: Following PRISMA-NMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Network Meta-analyses) guidelines, we searched PubMed, Medline, Embase and CINAHL up to 20 March 2024.

Utilization management and physician burnout.

Objective: This study was designed to assess physician experiences with utilization management and burnout and investigate whether they are linked.

Study Design: We conducted an electronic survey with items related to demographics, profession, utilization management, burnout, and potential policy solutions.

Methods: The survey was sent to 7222 physicians working in outpatient settings who were recruited from a large, opt-in database.