Yerbamate Tea Consumption: A Protective Factor in Parkinson Disease.

INTRODUCTION: Little is known about the association between Yerbamate (YMT) tea consumption and Parkinson disease (PD). We determined whether there was an association between YMT tea consumption and PD. METHODS: We conducted a multicenter case-control study in 3 countries (Argentina, Paraguay, and Uruguay). We applied a structured questionnaire about YMT tea consumption history. The survey also included information about factors previously associated with a decreased and increased risk of PD, apart from medical and demographic factors. Odds ratios and 95% confidence intervals were calculated using multivariate unconditional binary logistic regression analysis. RESULTS: We included 215 cases and 219 controls. The mean age of the cases was 65.6 ± 10.5 years and that of controls was 63.1 ± 10.5 years (P < 0.02). Years of YMT tea consumption, number of liters drunk per day, and amount of YMT used for preparing the infusion were similar between cases and controls (P > 0.05), but not the number of times the YMT was added into the container (P = 0.003) and the YMT tea concentration per serving (P = 0.02). The multivariate analysis showed that YMT tea concentration per serving lowered the risk for PD, independent of potential confounders (odds ratio, 0.62; 95% confidence interval, 0.47-0.84). CONCLUSIONS: This multicenter study highlights the association between an environmental factor, the YMT tea drinking, and PD. Although more evidence from longitudinal studies is needed, the results obtained here points toward a protective effect of the YMT tea concentration per serving on PD.

Impulsivity is associated with firing regularity in parkinsonian ventral subthalamic nucleus.

Impulsive-compulsive behaviors (ICB) are over-represented in Parkinson's disease (PD) patients. Neurons in the ventral subthalamic nucleus (STN) might play a predominant role in the modulation of impulsivity. We characterized the firing regularity of 742 subthalamic neurons from 24 PD patients (12 ICB+ and 12 ICB-) in an OFF medication state. We computed the firing regularity in the dorsal and ventral STN regions, and we compared their performance in discriminating ICB patients. Regularity of ventral neurons in ICB+ patients is higher and supports a significant discrimination between the two cohorts. These results substantiate a ventral location of neurons involved in impulsivity.

Adherence to treatment in Parkinson's disease: A multicenter exploratory study with patients from six Latin American countries.

BACKGROUND: Adherence to treatment in Parkinson's disease (PD) is compromised due to the need for multiple therapies, comorbidities related to aging, and the complexity of therapeutic schemes. In the present study, we aimed to explore adherence to treatment in groups of PD patients from six Latin-American (LA) countries and identify its associated demographic and clinical parameters. METHODS: A multicenter, cross-sectional, exploratory study was conducted from September 2016 to March 2017. Treatment adherence was assessed using the simplified medication adherence questionnaire (SMAQ), applied to patients and caregivers. Sociodemographic and clinical variables (MDS-UPDRS Part III-IV, MMSE, Beck Depression Inventory-II (BDI-II)) were recorded. RESULTS: Eight hundred patients from six LA countries were evaluated. Nonadherence was reported in 58.25% of the population, according to patients. The most frequent issues were forgetfulness and correct timing of doses. A high level of agreement in adherence prevalence and most SMAQ items were observed between patients and their caregivers. The nonadherent population had a significantly higher proportion of unemployment, free access to medication, troublesome dyskinesias and off-periods, lesser years of education, and worse motor, cognitive, and mood scores. In multiple logistic and linear regression analyses, MDS-UPDRS Part III, BDI-II, gender, free access to medication, treatment with dopamine agonists alone, years of education, excessive concerns about adverse effects, and beliefs about being well-treated remained significant contributors to adherence measures. CONCLUSION: Educational strategies, greater involvement of PD patients in decision-making, and consideration of their beliefs and values might be of great need to improve medication adherence in this PD population.

Consensus guidelines for botulinum toxin therapy: general algorithms and dosing tables for dystonia and spasticity.

Botulinum toxin (BT) therapy is a complex and highly individualised therapy defined by treatment algorithms and injection schemes describing its target muscles and their dosing. Various consensus guidelines have tried to standardise and to improve BT therapy. We wanted to update and improve consensus guidelines by: (1) Acknowledging recent advances of treatment algorithms. (2) Basing dosing tables on statistical analyses of real-life treatment data of 1831 BT injections in 36 different target muscles in 420 dystonia patients and 1593 BT injections in 31 different target muscles in 240 spasticity patients. (3) Providing more detailed dosing data including typical doses, dose variabilities, and dosing limits. (4) Including total doses and target muscle selections for typical clinical entities thus adapting dosing to different aetiologies and pathophysiologies. (5) In addition, providing a brief and concise review of the clinical entity treated together with general principles of its BT therapy. For this, we collaborated with IAB-Interdisciplinary Working Group for Movement Disorders which invited an international panel of experts for the support.

Impulsivity Markers in Parkinsonian Subthalamic Single-Unit Activity.

BACKGROUND: Impulsive-compulsive behaviors are common in Parkinson's disease (PD) patients. However, the basal ganglia dysfunctions associated with high impulsivity have not been fully characterized. The objective of this study was to identify the features associated with impulsive-compulsive behaviors in single neurons of the subthalamic nucleus (STN). METHODS: We compared temporal and spectral features of 412 subthalamic neurons from 12 PD patients with impulsive-compulsive behaviors and 330 neurons from 12 PD patients without. Single-unit activities were extracted from exploratory microrecordings performed during deep brain stimulation (DBS) implant surgery in an OFF medication state. RESULTS: Patients with impulsive-compulsive behaviors displayed decreased firing frequency during bursts and a larger fraction of tonic neurons combined with weaker beta coherence. Information carried by these features led to the identification of patients with impulsive-compulsive behaviors with an accuracy greater than 80%. CONCLUSIONS: Impulsive-compulsive behaviors in PD patients are associated with decreased bursts in STN neurons in the OFF medication state. © 2021 International Parkinson and Movement Disorder Society.

Successful Unilateral Surgical Approach to Internal Globus Pallidus and Ventral Intermediate Nucleus of the Thalamus in 3 Cases of Myoclonus-Dystonia Syndrome.

Surgical approaches of internal globus pallidus (GPi) and ventral intermediate thalamic nucleus (Vim) have been used to treat different movement disorders. Three subjects with myoclonus-dystonia syndrome were surgically treated, one of them with GPi and Vim stimulation, while radiofrequency ablation of these structures was performed in the other 2 subjects. Surgical approach of both targets was performed simultaneously on each subject. Mean follow-up was of 33.3 months (22-48 months), the Unified Myoclonus Rating Scale action myoclonus (AM), functional tests (FT), patient questionnaire (PQ) sub-scores, and the Unified Dystonia Rating Scale (UDRS) were used during assessments. Improvement in all scales were seen 6 months after surgery (AM: 74%, FT: 60%, PQ: 63%, UDRS: 65%), and this benefit persisted throughout follow-up (AM: 61%, FT:62%, PQ: 65%, UDRS: 86%). No adverse events were noticed. Simultaneous unilateral procedures of GPi and Vim by either stimulation or ablation techniques improve both motor and functional scores in myoclonus-dystonia syndrome.

Cannabis in patients with Parkinson's disease in Argentina. A cross sectional study.

We made an observational cross-sectional study to evaluate the prevalence of cannabis use, characteristics and results perceived by a group of PD patients. Semi-structured questionnaire was applied to patients. Until obtaining more information we suggest to incorporate into regular medical practice the question about the use of cannabis.

Blepharospasm as a Manifestation of Peak of Dose Dyskinesia in Parkinson Disease.

OBJECTIVES: The aim of the study was to report 4 patients with Parkinson disease (PD) and On-period blepharospasm (BS). METHODS: We analyzed patients with PD and motor fluctuations who developed BS in several different centers in Latin America. RESULTS: Four patients had BS while in the ON periods. CONCLUSIONS: Blepharospasm in the On period in patients with PD is extremely uncommon, and our series is the only one to describe such association.

Weight Loss in Parkinson's Disease: The Relationship with Motor Symptoms and Disease Progression.

OBJECTIVES: To determine the prevalence of weight loss (WL) in PD patients, its relationship to the severity of motor manifestations and appetite changes. METHODS: 144 PD patients and 120 controls were evaluated in a single session. All subjects were asked about changes in body weight and appetite. PD patients were examined with the UPDRS-III and the Hoehn and Yahr (HY) scales. Subscores of tremor, bradykinesia /rigidity, and non-dopaminergic symptoms (NDS) were analyzed individually. Multivariable logistic regression analysis was used to determine an association between WL and PD motor manifestations. RESULTS: 48.6 % of PD patients presented WL compared to 20.8 % of controls (p < 0.001). Weight losers were significantly older and had longer disease duration, higher scores in HY stages, UPDRS-III, and NDS-subscore. Multivariable logistic regression analysis demonstrated that WL was associated with NDS-subscore (p= 0.002; OR: 1.33) and older age (p= 0.037; OR: 1.05). Appetite in PD cases losing weight was unchanged (35.7 %), decreased (31.4 %), or even increased (32.9). CONCLUSIONS: Our results showed that WL occurs in almost half of PD patients and it is largely the consequence of disease progression rather than involuntary movements or a decrease in food intake.

Defining spasticity: a new approach considering current movement disorders terminology and botulinum toxin therapy.

Spasticity is a symptom occurring in many neurological conditions including stroke, multiple sclerosis, hypoxic brain damage, traumatic brain injury, tumours and heredodegenerative diseases. It affects large numbers of patients and may cause major disability. So far, spasticity has merely been described as part of the upper motor neurone syndrome or defined in a narrowed neurophysiological sense. This consensus organised by IAB-Interdisciplinary Working Group Movement Disorders wants to provide a brief and practical new definition of spasticity-for the first time-based on its various forms of muscle hyperactivity as described in the current movement disorders terminology. We propose the following new definition system: Spasticity describes involuntary muscle hyperactivity in the presence of central paresis. The involuntary muscle hyperactivity can consist of various forms of muscle hyperactivity: spasticity sensu strictu describes involuntary muscle hyperactivity triggered by rapid passive joint movements, rigidity involuntary muscle hyperactivity triggered by slow passive joint movements, dystonia spontaneous involuntary muscle hyperactivity and spasms complex involuntary movements usually triggered by sensory or acoustic stimuli. Spasticity can be described by a documentation system grouped along clinical picture (axis 1), aetiology (axis 2), localisation (axis 3) and additional central nervous system deficits (axis 4). Our new definition allows distinction of spasticity components accessible to BT therapy and those inaccessible. The documentation sheet presented provides essential information for planning of BT therapy.

Erratum: Variable frequency of LRRK2 variants in the Latin American research consortium on the genetics of Parkinson's disease (LARGE-PD), a case of ancestry.

[This corrects the article DOI: 10.1038/s41531-017-0020-6.].

Variable frequency of LRRK2 variants in the Latin American research consortium on the genetics of Parkinson's disease (LARGE-PD), a case of ancestry.

Mutations in Leucine-Rich Repeat Kinase 2 (LRRK2), primarily located in codons G2019 and R1441, represent the most common genetic cause of Parkinson's disease in European-derived populations. However, little is known about the frequency of these mutations in Latin American populations. In addition, a prior study suggested that a LRRK2 polymorphism (p.Q1111H) specific to Latino and Amerindian populations might be a risk factor for Parkinson's disease, but this finding requires replication. We screened 1734 Parkinson's disease patients and 1097 controls enrolled in the Latin American Research Consortium on the Genetics of Parkinson's disease (LARGE-PD), which includes sites in Argentina, Brazil, Colombia, Ecuador, Peru, and Uruguay. Genotypes were determined by TaqMan assay (p.G2019S and p.Q1111H) or by sequencing of exon 31 (p.R1441C/G/H/S). Admixture proportion was determined using a panel of 29 ancestry informative markers. We identified a total of 29 Parkinson's disease patients (1.7%) who carried p.G2019S and the frequency ranged from 0.2% in Peru to 4.2% in Uruguay. Only two Parkinson's disease patients carried p.R1441G and one patient carried p.R1441C. There was no significant difference in the frequency of p.Q1111H in patients (3.8%) compared to controls (3.1%; OR 1.02, p = 0.873). The frequency of LRRK2-p.G2019S varied greatly between different Latin American countries and was directly correlated with the amount of European ancestry observed. p.R1441G is rare in Latin America despite the large genetic contribution made by settlers from Spain, where the mutation is relatively common.

A Multicenter Comparative Study of Impulse Control Disorder in Latin American Patients With Parkinson Disease.

OBJECTIVES: Impulse control disorder (ICD) is a common adverse effect in patients with Parkinson disease who receive dopamine agonists; however, other factors are involved in its manifestations. To study the frequency and factors involved in the development of this adverse effect in a Latin American population, we conducted a cross-sectional multicenter study. METHODS: Two hundred fifty-five patients in 3 Latin American centers were evaluated by examination and application of scales (Unified Parkinson's Disease Rating Scale, Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease-Rating Scale, Hoehn and Yahr, Clinical Impression of Severity Index for Parkinson's Disease). RESULTS: Of the patients, 27.4% had ICD, most of whom were on dopamine agonists. Other associated risk factors included a younger age at onset of Parkinson disease, moderate symptoms, a shorter evolution of the clinical manifestations, rapid eye movement (REM) sleep disorder behavior, and the consumption of tea, mate, and alcohol. CONCLUSIONS: The frequency of ICD is higher in Latin America than in Anglo-Saxon populations. Consuming tea and mate, in addition to the use of dopamine agonists, is a factor that may demonstrate a genetic link that predisposes patients to the establishment of an ICD.

Alcohol-Sensitive Generalized Dystonia.

We report the case of a 29-year-old male patient with a generalized and progressive dystonia that led him unable to stand. Multiple antidystonic treatments were tried without benefit. Alcohol test was positive with a dramatic improvement. To the best of our knowledge, this is the first reported case of generalized dystonia without other clinical manifestations sensitive to alcohol.

Botulinum toxin therapy for treatment of spasticity in multiple sclerosis: review and recommendations of the IAB-Interdisciplinary Working Group for Movement Disorders task force.

Botulinum toxin (BT) therapy is an established treatment of spasticity due to stroke. For multiple sclerosis (MS) spasticity this is not the case. IAB-Interdisciplinary Working Group for Movement Disorders formed a task force to explore the use of BT therapy for treatment of MS spasticity. A formalised PubMed literature search produced 55 publications (3 randomised controlled trials, 3 interventional studies, 11 observational studies, 2 case studies, 35 reviews, 1 guideline) all unanimously favouring the use of BT therapy for MS spasticity. There is no reason to believe that BT should be less effective and safe in MS spasticity than it is in stroke spasticity. Recommendations include an update of the current prevalence of MS spasticity and its clinical features according to classifications used in movement disorders. Immunological data on MS patients already treated should be analysed with respect to frequencies of MS relapses and BT antibody formation. Registration authorities should expand registration of BT therapy for spasticity regardless of its aetiology. MS specialists should consider BT therapy for symptomatic treatment of spasticity.