Worldwide barriers to genetic testing for movement disorders.

BACKGROUND AND PURPOSE: Despite enormous advances in identifying genetic variants responsible for many neurological diseases, access to genetic testing may be limited in clinical practice. The objective of this study was to assess worldwide access to genetic tests for movement disorders and factors impacting their utilization. METHODS: The Rare Movement Disorders Study Group of the International Parkinson and Movement Disorder Society designed an online survey electronically mailed to all 7815 members. RESULTS: Survey data completed by 1269 participants from 109 countries were analysed. Limited access to geneticists and genetic counsellors was reported in many world regions compared to Europe and North America. Availability of genetic testing was limited, with rates of access lower than 50%. Genetic testing for chorea was the most commonly available. For parkinsonism, dystonia, ataxia, hereditary spastic paraplegias and metabolic disorders, there was limited access to genetic testing in all countries compared to Europe and North America, with significant differences found for Africa, Central/South America, Asia. In many regions, genetic testing was supported by either private or public funding. Genetic testing was free of charge in Europe according to 63.5% of respondents. In North America, Africa, Central/South America, Asia and the Middle East access to free of charge genetic testing was by far significantly lower compared to Europe. CONCLUSIONS: This survey highlights difficulties in accessing genetic testing and individuals with expertise in genetics at the worldwide level. In addition, major disparities in genetic testing amongst world regions are highlighted, probably due to a variety of factors including financial barriers.

Global Survey on Telemedicine Utilization for Movement Disorders During the COVID-19 Pandemic.

BACKGROUND: The COVID-19 pandemic restricted usual healthcare management for movement-disorders patients, with a consequent upsurge in telemedicine to bridge the gap. OBJECTIVE: To assess global telemedicine usage in the context of the pandemic. METHODS: The Movement Disorder Society (MDS) Telemedicine Study Group surveyed telemedicine experts from 40 countries across all continents in March-April 2020. Four domains of telemedicine were assessed: legal regulations, reimbursement, clinical use, and barriers; comparing emerging responses to the pandemic versus the baseline scenario. RESULTS: All forms of telemedicine for movement disorders increased globally, irrespective of country income categorization, as an immediate response to the pandemic. This was aided by widespread availability of technology and updated government regulations. However, privacy concerns, lack of reimbursement, limited access, and lack of telemedicine training were barriers highlighted worldwide. CONCLUSIONS: Questions remain about the longevity and extent of changes in regulations and reimbursement regarding telemedicine in the aftermath of the pandemic. © 2020 International Parkinson and Movement Disorder Society.

Treatable inherited rare movement disorders.

There are many rare movement disorders, and new ones are described every year. Because they are not well recognized, they often go undiagnosed for long periods of time. However, early diagnosis is becoming increasingly important. Rapid advances in our understanding of the biological mechanisms responsible for many rare disorders have enabled the development of specific treatments for some of them. Well-known historical examples include Wilson disease and dopa-responsive dystonia, for which specific and highly effective treatments have life-altering effects. In recent years, similarly specific and effective treatments have been developed for more than 30 rare inherited movement disorders. These treatments include specific medications, dietary changes, avoidance or management of certain triggers, enzyme replacement therapy, and others. This list of treatable rare movement disorders is likely to grow during the next few years because a number of additional promising treatments are actively being developed or evaluated in clinical trials. © 2017 International Parkinson and Movement Disorder Society.

Telemedicine Use for Movement Disorders: A Global Survey.

BACKGROUND: Telemedicine is increasingly used to care for patients with movement disorders, but data regarding its global use are limited. INTRODUCTION: To obtain baseline international data about telemedicine use among movement disorder clinicians. METHODS: An online survey was sent to all 6,056 Movement Disorder Society members in 2015. Scope, reimbursement, and perceived quality of telemedicine were assessed. RESULTS: There were 549 respondents (9.1% overall response rate) from 83 countries. Most (85.8%) were physicians, and most (70.9%) worked in an academic or university practice. Half of respondents (n = 287, from 57 countries) used telemedicine for clinical care; activities included e-mail (63.2%), video visits (follow-up [39.7%] and new [35.2%]), and video-based education (35.2%). One hundred five respondents personally conducted video visits, most frequently to outpatient clinics (53.5%), patient homes (30.8%), and hospital inpatients (30.3%). The most common challenges were a limited neurological examination (58.9%) and technological difficulties (53.3%), and the most common benefits were reduced travel time (92.9%) and patient costs (60.1%). The most frequent reimbursements were none (39.0%), public insurance (24.5%), and patient payment (9.3%). Half of respondents planned to use telemedicine in the future, and three-quarters were interested in telemedicine education. CONCLUSIONS: More than 250 respondents around the world engage in telemedicine for movement disorders; most perceived benefit for patients, despite challenges and reimbursement for clinicians. Formal instruction on telemedicine is highly desired. Although the survey response was low and possibly biased to over represent those with telemedicine experience, the study provides baseline data for future comparison and to improve telemedicine delivery.

Prodromal Clinical Markers of Parkinson disease in Gaucher Disease Individuals.

Heterozygous mutations in the glucocerebrosidase (GBA) gene have been reported as a common risk factor for the development of Parkinson's disease (PD) in Gaucher disease (GD) patients and in heterozygous GBA mutation positive carriers. In this study, we analyzed the occurrence of prodromal markers of PD in an Argentinean cohort with type 1 GD. After signed informed consent, we evaluated 26 patients with type 1 GD under enzymatic replacement therapy from a cohort of the Hospital Ricardo Gutierrez GD Study Group in Buenos Aires City, Argentina. We performed an extensive neurological examination, including cognitive assessment by Montreal Cognitive Assessment (MoCA) and a questionnaire performed ad hoc, to identify non-motor PD symptoms. Parasomnias were reported by 7 patients (26.92%), rapid eye movement behavior disorders in 2 (7.69%), constipation in 2 (7.69%), hyposmia in 1 (3.84%), tremor in 1 (3.84%), and depression in 3 cases (11.53%). MoCA assessment was abnormal in 44.44% of patients. No patient fulfilled PD diagnostic criteria (Queen Square Brain Bank criteria). The identification of prodromal markers of PD in type 1 GD suggests that this population represents a very interesting cohort for identifying potential biomarkers and neuroprotective therapies for PD.

[Rational use of psychotropic medications and sedative load in older adults with and without dementia]. / Uso de psicofármacos y carga sedativa en pacientes adultos con y sin demencia.

Sedative drugs use has been associated with more cognitive impairment and increased mortality. Sedative load refers to cumulative exposure to multiple drugs with sedative properties. OBJECTIVE: Describe the use of psychotropic drugs and sedative load in older adults with and without dementia. MATERIAL AND METHODS: We conducted a cross-sectional study from 2014-2015 (Sanatorio Trinidad Mitre), in hospitalized patients older than 65 years old. Drugs were classified according to the WHO ATC system. The sedative load of drugs was calculated using the Linjakumpu model. RESULTS: 152 PsD and 35 PcD patients were registered, mean age 80.8±8.42. Polypharmacy was present in 44.39% being higher in patients with dementia than without dementia (62.80% vs 40.13%, p=0.0147). In 40.64% at least one psychotropic/sedative medication was used, greater in PcD (60% vs 36.18%, p=0.0097). The CS was: 1.32±1.59; 2.14 in PcD and 1.13 in PsD (p<0.001). Atypical antipsychotics and benzodiazepines were the most common (51.43 and 40% respectively) in patients without dementias. CONCLUSION: we evidenced a high level of prescription psychotropic or sedative drugs, mostly in patients with dementia. In those, the sedative load was greater. This finding highlights the importance of implementing strategies to optimize sedative drug use among older people.

Repeat interruptions in spinocerebellar ataxia type 10 expansions are strongly associated with epileptic seizures.

Spinocerebellar ataxia type 10 (SCA10), an autosomal dominant neurodegenerative disorder, is the result of a non-coding, pentanucleotide repeat expansion within intron 9 of the Ataxin 10 gene. SCA10 patients present with pure cerebellar ataxia; yet, some families also have a high incidence of epilepsy. SCA10 expansions containing penta- and heptanucleotide interruption motifs, termed "ATCCT interruptions," experience large contractions during germline transmission, particularly in paternal lineages. At the same time, these alleles confer an earlier age at onset which contradicts traditional rules of genetic anticipation in repeat expansions. Previously, ATCCT interruptions have been associated with a higher prevalence of epileptic seizures in one Mexican-American SCA10 family. In a large cohort of SCA10 families, we analyzed whether ATCCT interruptions confer a greater risk for developing seizures in these families. Notably, we find that the presence of repeat interruptions within the SCA10 expansion confers a 6.3-fold increase in the risk of an SCA10 patient developing epilepsy (6.2-fold when considering patients of Mexican ancestry only) and a 13.7-fold increase in having a positive family history of epilepsy (10.5-fold when considering patients of Mexican ancestry only). We conclude that the presence of repeat interruptions in SCA10 repeat expansion indicates a significant risk for the epilepsy phenotype and should be considered during genetic counseling.

Suicide attempt in a dopamine agonist withdrawal syndrome in Parkinson's disease.

Dopamine agonist withdrawal syndrome (DAWS) results from the reduction or suspension of dopamine agonist medications; it encompasses mainly psychiatric symptoms, including suicidal behaviors. In patients with Parkinson's disease (PD), the impact of DAWS can be significant in terms of distress and disability; however, we must take this syndrome into account as a threatening condition because suicidal behaviors could be developing in the context of DAWS. Here we present a brief case of DAWS affecting a young man with PD, whom abruptly discontinued DA treatment and developed psychiatric symptoms within two weeks which led to a suicidal attempt.

Discharges With Triphasic Morphology as Marker of the Risk of Death in Acute Encephalopathy.

Introduction. In clinical practice, it is difficult to define the prognosis of patients with acute encephalopathy; a syndrome characterized by cognitive dysfunction and altered sensorium. Discharges with triphasic morphology (DTM) are an electroencephalographic pattern that might be useful to establish the risk of death. The aim of this study was to define the prognostic value of DTM regarding mortality in patients with acute encephalopathy. Methods. We conducted an observational retrospective cohort study including patients with acute encephalopathy with and without DTM paired by age and gender in a 1:2 ratio. We calculated the odds ratio (OR) to determine the association between DTM and mortality. In addition, we calculated sensibility, specificity, and predictive values. Results. We included 72 patients, 24 with DTM and 48 without DTM. Mortality was higher in patients with DTM (41.6% vs 14.5%, P = .01). Factors associated with a higher risk of death were DTM (OR = 4.1, 95% confidence interval [CI] 1.3-13, P = .01) and sequential organ failure assessment score (OR = 1.3, 95% CI 1.04-1.67, P = .02). A higher Glasgow coma scale score was associated with a lower risk of death (OR = 0.65, 95% CI 0.51-0.83, P = .001). The sensibility and specificity of DTM were 59% and 75%, respectively. Positive and negative likelihood ratios were 2.36 and 0.55. Discussion. Our results revealed high mortality in patients with acute encephalopathy and DTM. This electroencephalographic pattern was associated with 4 times higher risk of death. However, its usefulness for predicting death was limited.

Review of Hereditary and Acquired Rare Choreas.

Background: Movement disorders are often a prominent part of the phenotype of many neurologic rare diseases. In order to promote awareness and diagnosis of these rare diseases, the International Parkinson's and Movement Disorders Society Rare Movement Disorders Study Group provides updates on rare movement disorders. Methods: In this narrative review, we discuss the differential diagnosis of the rare disorders that can cause chorea. Results: Although the most common causes of chorea are hereditary, it is critical to identify acquired or symptomatic choreas since these are potentially treatable conditions. Disorders of metabolism and mitochondrial cytopathies can also be associated with chorea. Discussion: The present review discusses clues to the diagnosis of chorea of various etiologies. Authors propose algorithms to help the clinician in the diagnosis of these rare disorders.

Huntington disease: Advances in the understanding of its mechanisms.

Huntington disease (HD) is a devastating monogenic autosomal dominant disorder. HD is caused by a CAG expansion in exon 1 of the gene coding for huntingtin, placed in the short arm of chromosome 4. Despite its well-defined genetic origin, the molecular and cellular mechanisms underlying the disease are unclear and complex. Here, we review some of the currently known functions of the wild-type huntingtin protein and discuss the deleterious effects that arise from the expansion of the CAG repeats, which are translated into an abnormally long polyglutamine tract. Also, we present a modern view on the molecular biology of HD as a representative of the group of polyglutamine diseases, with an emphasis on conformational changes of mutant huntingtin, disturbances in its cellular processing, and proteolytic stress in degenerating neurons. The main pathogenetic mechanisms of neurodegeneration in HD are discussed in detail, such as autophagy, impaired mitochondrial biogenesis, lysosomal dysfunction, organelle and protein transport, inflammation, oxidative stress, and transcription factor modulation. However, other unraveling mechanisms are still unknown. This practical and brief review summarizes some of the currently known functions of the wild-type huntingtin protein and the recent findings related to the mechanisms involved in HD pathogenesis.

Moaning Phenomenon and Rapidly Progressive Dementia in Anti LGI-1 Associated Progressive Supranuclear Palsy Syndrome.

Background: Immunological causes of atypical parkinsonisms linked to neuronal specific antibodies have been recently reported. As these are potentially treatable disorders, it is desirable to identify which clinical features may suggest an autoimmune etiology. Case Report: A 60-year-old-man with progressive supranuclear palsy associated with anti-LGI-1 antibodies presented with rapidly progressive dementia and moaning. Treatment with steroids and immunoglobulin resulted in temporary clinical improvement and disease stabilization. Discussion: Anti-LGI-1 antibodies interfere with normal synaptic activity and maturation in the central nervous system. We suggest that an immune-mediated mechanism might be considered in atypical parkinsonisms with unusual features such as rapidly progressive dementia. Highlights: We present a case of rapidly evolving progressive supranuclear palsy-like parkinsonism associated with anti-LGI-1 antibodies, suggesting that immune-mediated mechanisms might be involved in rapid progression of some atypical parkinsonisms. This case also contributes to the expanding spectrum of moaning-associated disorders.

A novel mutation in PSEN1 (p.Arg41Ser) in an Argentinian woman with early onset Parkinsonism.

INTRODUCTION: Mutations in presenilin-1 (PSEN1) account for the majority of cases of familial autosomal dominant early-onset Alzheimer's disease (AD) as well as in sporadic forms. Atypical presentations are reported including extrapyramidal signs. In the last years, a pleiotropic effect of some PSEN1 variants has been reported in Parkinson's disease (PD). OBJECTIVE: to report a new PSEN1 mutation characterized by early-onset Parkinsonism (EOPD) without dementia or classical AD biomarkers phenotype. PATIENT AND METHODS: An Argentinian 46 years old woman was diagnosed with EOPD at 35 years old with no family history of neurodegenerative disorders. Her medical history included iron deficiency and anemia since childhood. A brain MRI showed moderate frontal atrophy. 18FDG-PET and PiB-PET as well as CSF biomarkers were inconclusive for AD. Two neuropsychological examinations were compatible with a mild non amnestic cognitive impairment. Whole blood DNA was extracted and whole exome sequencing and analysis was performed. RESULTS AND CONCLUSION: A heterozygous novel missense PSEN1 mutation (position 14:73637540, A > T, pArg41Ser) was identified as a likely causative mutation in this patient. To the best of our knowledge, this case is the first PSEN1 mutation with a l-dopa responsive Parkinsonism lacking distinctive classical AD biomarkers. This case opens a new window to explore the pathophysiological link among PSEN1 and EOPDs and contributes to increase the phenotypes of PSEN1 variants.

[Apathy in Parkinson's disease. Impairment in quality of life]. / Apatía en enfermedad de Parkinson. Impacto sobre la calidad de vida.

Apathy is one of the most prominent non-motor symptoms in Parkinson Disease (PD). Its range of prevalence in PD has been estimated in 20 to 45%. The objective of this work is to assess the prevalence of apathy in PD patients, and its relation with depression and executive function impairment. Fifty seven PD patients (54% women), mean age of 68.7 years, and a disease duration of 7.5 years from diagnosis were included. We used the following scales: UPDRS, Hoehn & Yahr, Mini Mental State Examination, the 14-item Apathy Scale (AS), the Beck Depression Inventory, and Trail Making Test versions A and B (TMT), and Parkinson's Disease Quality of Life Questionnaire (PDQL). Apathy was identified in 31.6%; apathy without depression was present in 33.3% of patients. The TMT A and B were abnormal in 66.7% and 83.3% respectively of the apathetic patients vs. 46.2% and 61.5% in non-apathetic patients. Quality of life was impaired in apathetic patients. In our PD sample apathy is highly prevalent, has a great impact on quality of life and it may occur in the absence of depression. The alterations of TMT in apathetic patients contributes to suggest a positive relationship between apathy and the impairment of executive function secondary to the involvement of frontal-subcortical circuits.

Impulse Control Disorders in Parkinson's Disease. A Brief and Comprehensive Review.

Impulse control and related disorders (ICDs-RD) encompasses a heterogeneous group of disorders that involve pleasurable behaviors performed repetitively, excessively, and compulsively. The key common symptom in all these disorders is the failure to resist an impulse or temptation to control an act or specific behavior, which is ultimately harmful to oneself or others and interferes in major areas of life. The major symptoms of ICDs include pathological gambling (PG), hypersexualtiy (HS), compulsive buying/shopping (CB) and binge eating (BE) functioning. ICDs and ICDs-RD have been included in the behavioral spectrum of non-motor symptoms in Parkinson's disease (PD) leading, in some cases, to serious financial, legal and psychosocial devastating consequences. Herein we present the prevalence of ICDs, the risk factors, its pathophysiological mechanisms, the link with agonist dopaminergic therapies and therapeutic managements.

Parkinsonisms and Glucocerebrosidase Deficiency: A Comprehensive Review for Molecular and Cellular Mechanism of Glucocerebrosidase Deficiency.

In the last years, lysosomal storage diseases appear as a bridge of knowledge between rare genetic inborn metabolic disorders and neurodegenerative diseases such as Parkinson's disease (PD) or frontotemporal dementia. Epidemiological studies helped promote research in the field that continues to improve our understanding of the link between mutations in the glucocerebrosidase (GBA) gene and PD. We conducted a review of this link, highlighting the association in GBA mutation carriers and in Gaucher disease type 1 patients (GD type 1). A comprehensive review of the literature from January 2008 to December 2018 was undertaken. Relevance findings include: (1) There is a bidirectional interaction between GBA and α- synuclein in protein homeostasis regulatory pathways involving the clearance of aggregated proteins. (2) The link between GBA deficiency and PD appears not to be restricted to α⁻synuclein aggregates but also involves Parkin and PINK1 mutations. (3) Other factors help explain this association, including early and later endosomes and the lysosomal-associated membrane protein 2A (LAMP-2A) involved in the chaperone-mediated autophagy (CMA). (4) The best knowledge allows researchers to explore new therapeutic pathways alongside substrate reduction or enzyme replacement therapies.