Symptomatic therapy of multiple system atrophy

Impact of Magnetic Resonance Imaging Markers on the Diagnostic Performance of the International Parkinson and Movement Disorder Society Multiple System Atrophy Criteria

BACKGROUND

Multiple system atrophy is a neurodegenerative disease with α-synuclein aggregation in glial cytoplasmic inclusions, leading to dysautonomia, parkinsonism, and cerebellar ataxia.

OBJECTIVE

The aim of this study was to validate the accuracy of the International Parkinson and Movement Disorder Society Multiple System Atrophy clinical diagnostic criteria, particularly considering the impact of the newly introduced brain magnetic resonance imaging (MRI) markers.

METHODS

Diagnostic accuracy of the clinical diagnostic criteria for multiple system atrophy was estimated retrospectively in autopsy-confirmed patients with multiple system atrophy, Parkinson's disease, progressive supranuclear palsy, and corticobasal degeneration.

RESULTS

We identified a total of 240 patients. Sensitivity of the clinically probable criteria was moderate at symptom onset but improved with disease duration (year 1: 9%, year 3: 39%, final ante mortem record: 77%), whereas their specificity remained consistently high (99%-100% throughout). Sensitivity of the clinically established criteria was low during the first 3 years (1%-9%), with mild improvement at the final ante mortem record (22%), whereas specificity remained high (99%-100% throughout). When MRI features were excluded from the clinically established criteria, their sensitivity increased considerably (year 1: 3%, year 3: 22%, final ante mortem record: 48%), and their specificity was not compromised (99%-100% throughout).

CONCLUSIONS

The International Parkinson and Movement Disorder Society multiple system atrophy diagnostic criteria showed consistently high specificity and low to moderate sensitivity throughout the disease course. The MRI markers for the clinically established criteria reduced their sensitivity without improving specificity. Combining clinically probable and clinically established criteria, but disregarding MRI features, yielded the best sensitivity with excellent specificity and may be most appropriate to select patients for therapeutic trials. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

[Multiple system atrophy]

The article presents a progressive neurodegenerative disease - multisystem atrophy, characterized by a combination of autonomic failure and various motor disorders, including parkinsonism and/or cerebellar ataxia; etiopathogenetic factors and variants of the clinical picture are described. We describe own clinical observation of a 59-old patient with cerebellar and bulbar syndromes, parkinsonism, pyramidal insufficiency, cognitive deficits, and autonomic dysfunction. The differential diagnosis included a whole range of neurodegenerative and hereditary diseases: Parkinson's disease, vascular parkinsonism, progressive supranuclear palsy, spinocerebellar ataxia, FXTAS, mitochondrial encephalopathies. The moderate severity of parkinsonism and the significant predominance of cerebellar symptoms and autonomic dysfunction make this clinical case difficult to diagnose. However, based on the life and disease history, clinical picture and research methods, a diagnosis of multiple system atrophy, cerebellar type (cerebellar, autonomic, bulbar syndrome, parkinsonism, pyramidal insufficiency and moderate cognitive impairment) was established. Differential search in such patients is a difficult task and includes a whole range of neurodegenerative and hereditary diseases due to the similarity of individual clinical and neuroimaging features and, unfortunately, the limited availability of molecular genetic diagnostic methods. However, earlier diagnosis is necessary to focus in time on the development of a personalized approach to the management of each such patient, taking into account the rate of symptoms development and steady progression, in order to ensure the longest possible survival time with an acceptable level of quality of life.

Pathomechanisms of depression in multiple system atrophy

Multiple system atrophy (MSA) is a rapidly progressing neurodegenerative disorder of uncertain etiology that is characterized by various combinations of Parkinsonism, autonomic, cerebellar and motor dysfunctions, with poor prognosis. Little is known about modifiable factors, such as depression, that has negative effects on quality of life in MSA. Depression, with an estimated prevalence of about 43%, is among the most common neuropsychiatric disorders in MSA similar to other atypical Parkinsonian disorders, the frequency of which is associated with increased disease progression, disease severity and autonomic dysfunctions. Depression in MSA, like in Parkinson disease, has been related to a variety of pathogenic mechanisms associated with the underlying neurodegenerative process, such as involvement of serotonergic neuron groups in the brainstem, prefrontal cortical dysfunctions, and altered functional fronto-temporal-thalamic connectivities with disturbances of mood related and other essential resting-state brain networks. The pathophysiology and pathogenesis of depression in MSA, as in other degenerative movement disorders, are complex and deserve further elucidation as a basis for adequate treatment to improve the quality of life in this fatal disease.

Common Variants Near ZIC1 and ZIC4 in Autopsy-Confirmed Multiple System Atrophy

BACKGROUND

Multiple System Atrophy is a rare neurodegenerative disease with alpha-synuclein aggregation in glial cytoplasmic inclusions and either predominant olivopontocerebellar atrophy or striatonigral degeneration, leading to dysautonomia, parkinsonism, and cerebellar ataxia. One prior genome-wide association study in mainly clinically diagnosed patients with Multiple System Atrophy failed to identify genetic variants predisposing for the disease.

OBJECTIVE

Since the clinical diagnosis of Multiple System Atrophy yields a high rate of misdiagnosis when compared to the neuropathological gold standard, we studied only autopsy-confirmed cases.

METHODS

We studied common genetic variations in Multiple System Atrophy cases (N = 731) and controls (N = 2898).

RESULTS

The most strongly disease-associated markers were rs16859966 on chromosome 3, rs7013955 on chromosome 8, and rs116607983 on chromosome 4 with P-values below 5 × 10-6 , all of which were supported by at least one additional genotyped and several imputed single nucleotide polymorphisms. The genes closest to the chromosome 3 locus are ZIC1 and ZIC4 encoding the zinc finger proteins of cerebellum 1 and 4 (ZIC1 and ZIC4).

INTERPRETATION

Since mutations of ZIC1 and ZIC4 and paraneoplastic autoantibodies directed against ZIC4 are associated with severe cerebellar dysfunction, we conducted immunohistochemical analyses in brain tissue of the frontal cortex and the cerebellum from 24 Multiple System Atrophy patients. Strong immunohistochemical expression of ZIC4 was detected in a subset of neurons of the dentate nucleus in all healthy controls and in patients with striatonigral degeneration, whereas ZIC4-immunoreactive neurons were significantly reduced inpatients with olivopontocerebellar atrophy. These findings point to a potential ZIC4-mediated vulnerability of neurons in Multiple System Atrophy. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Symptomatic Care in Multiple System Atrophy: State of the Art

Without any disease-modifying treatment strategy for multiple system atrophy (MSA), the therapeutic management of MSA patients focuses on a multidisciplinary strategy of symptom control. In the present review, we will focus on state of the art treatment in MSA and additionally give a short overview about ongoing randomized controlled trials in this field.

Effects of Non-invasive Brain Stimulation on Multiple System Atrophy: A Systematic Review

Background/Objective: Multiple system atrophy (MSA) refers to a progressive neurodegenerative disease characterized by autonomic dysfunction, parkinsonism, cerebellar ataxia, as well as cognitive deficits. Non-invasive brain stimulation (NIBS) has recently served as a therapeutic technique for MSA by personalized stimulation. The primary aim of this systematic review is to assess the effects of NIBS on two subtypes of MSA: parkinsonian-type MSA (MSA-P) and cerebellar-type MSA (MSA-C).

Methods: A literature search for English articles was conducted from PubMed, Embase, Web of Science, Cochrane Library, CENTRAL, CINAHL, and PsycINFO up to August 2021. Original articles investigating the therapeutics application of NIBS in MSA were screened and analyzed by two independent reviewers. Moreover, a customized form was adopted to extract data, and the quality of articles was assessed based on the PEDro scale for clinical articles.

Results: On the whole, nine articles were included, i.e., five for repetitive transcranial magnetic stimulation (rTMS), two for transcranial direct current stimulation (tDCS), one for paired associative stimulation, with 123 patients recruited. The mentioned articles comprised three randomized controlled trials, two controlled trials, two non-controlled trials, and two case reports which assessed NIBS effects on motor function, cognitive function, and brain modulatory effects. The majority of articles demonstrated significant motor symptoms improvement and increased cerebellar activation in the short term after active rTMS. Furthermore, short-term and long-term effects on improvement of motor performance were significant for tDCS. As opposed to the mentioned, no significant change of motor cortical excitability was reported after paired associative stimulation.

Conclusion: NIBS can serve as a useful neurorehabilitation strategy to improve motor and cognitive function in MSA-P and MSA-C patients. However, further high-quality articles are required to examine the underlying mechanisms and standardized protocol of rTMS as well as its long-term effect. Furthermore, the effects of other NIBS subtypes on MSA still need further investigation.

Evolving concepts in progressive supranuclear palsy and other 4-repeat tauopathies

Tauopathies are classified according to whether tau deposits predominantly contain tau isoforms with three or four repeats of the microtubule-binding domain. Those in which four-repeat (4R) tau predominates are known as 4R-tauopathies, and include progressive supranuclear palsy, corticobasal degeneration, argyrophilic grain disease, globular glial tauopathies and conditions associated with specific MAPT mutations. In these diseases, 4R-tau deposits are found in various cell types and anatomical regions of the brain and the conditions share pathological, pathophysiological and clinical characteristics. Despite being considered 'prototype' tauopathies and, therefore, ideal for studying neuroprotective agents, 4R-tauopathies are still severe and untreatable diseases for which no validated biomarkers exist. However, advances in research have addressed the issues of phenotypic overlap, early clinical diagnosis, pathophysiology and identification of biomarkers, setting a road map towards development of treatments. New clinical criteria have been developed and large cohorts with early disease are being followed up in prospective studies. New clinical trial readouts are emerging and biomarker research is focused on molecular pathways that have been identified. Lessons learned from failed trials of neuroprotective drugs are being used to design new trials. In this Review, we present an overview of the latest research in 4R-tauopathies, with a focus on progressive supranuclear palsy, and discuss how current evidence dictates ongoing and future research goals.

Amelioration of motor and nonmotor symptoms in cortical cerebellar atrophy and multiple system atrophy-cerebellar type by inpatient rehabilitation: a retrospective study

Sporadic spinocerebellar degenerative diseases such as multiple system atrophy (cerebellar type) and cortical cerebellar atrophy typically present with cerebellar ataxia. Multiple system atrophy is characterized by ataxia, with parkinsonism, dysautonomia and neuropsychiatric symptoms, resulting in reduced quality of life. Effects of physical rehabilitation focused on motor symptoms with ataxia in nonmultiple system atrophy patients have been reported; however, without addressing concomitant nonmotor symptoms. Here, we examined the motor, nonmotor and quality of life effects of inpatient physical rehabilitation in 15 multiple systems atrophy and nine cortical cerebellar atrophy patients without dementia. Rehabilitation involved a 4-week hospitalization with physical, occupational and speech therapy. The following assessments were conducted at admission and discharge: the scale for the assessment and rating of ataxia for ataxia; Montreal cognitive assessment for cognition, hospital anxiety and depression scale for emotion and medical outcomes study short-form for health-related quality of life. Data were analyzed for statistical significance (P < 0.05) using the Wilcoxon signed-rank test. In patients with multiple system atrophy, rehabilitation significantly improved ataxia, cognition with mild cognitive impairment (73.3%) and health-related quality of life; however, patients with depression (86.7%) showed no improvement in emotional health and quality of life. Similar effects on motor and nonmotor symptoms were observed in patients with cortical cerebellar atrophy. This suggests that inpatient rehabilitation could not only improve motor and nonmotor functions, but also the quality of life in patients with spinocerebellar degenerative disease.

Short-Term Effect of Intensive Speech Therapy on Dysarthria in Patients With Sporadic Spinocerebellar Degeneration

Purpose The aim of this study was to investigate a structured approach for effective speech therapy (ST) for dysarthria and speech-related quality of life in patients with sporadic spinocerebellar degeneration (SCD), including cerebellar-type multiple-system atrophy and cerebellar cortical atrophy. Method Twenty-two patients with SCD (cerebellar-type multiple system atrophy, 15 patients; cerebellar cortical atrophy, seven patients) who underwent intensive ST were examined. Dysarthria was evaluated using the Scale for Assessment and Rating of Ataxia Speech Dysfunction, Assessment of Motor Speech for Dysarthria Articulation, oral diadochokinesis (OD), and Voice Handicap Index-10 (VHI-10). Respiratory muscle strength (inspiratory and expiratory pressure) and respiratory-phonatory coordination (maximum phonation time) were measured. Cognitive function was evaluated using the Montréal Cognitive Assessment and the word fluency test. Mood was evaluated using the Hospital Anxiety and Depression Scale. The relationships between dysarthria scales (particularly, VHI-10) and clinical data were analyzed using stepwise regression. The differences in outcomes after intensive ST were analyzed using the Wilcoxon signed-rank test. The alpha level (p) for statistical significance was set at .0125 by Bonferroni correction. Results For both pre- and post-ST, the patient's OD (p = .002) and maximum phonation time (p = .002) significantly improved, except for Speech Dysfunction scores of the Scale for Assessment and Rating of Ataxia (p = .705) and the VHI-10 (p = .018). The Assessment of Motor Speech for Dysarthria Articulation, OD, and inspiratory pressure were identified as independent variables of VHI-10 (adjusted R ² = .820) for speech-related quality of life; no correlations among the Montréal Cognitive Assessment, word fluency test, and Hospital Anxiety and Depression Scale scores were observed. Conclusion OD and VHI-10 showed improvements due to changes in speech function and respiratory-phonatory coordination, justifying intensive ST treatment for dysarthria in patients with SCD.

Current Management and Emerging Therapies in Multiple System Atrophy

Multiple system atrophy (MSA) is a progressive neurodegenerative disease variably associated with motor, nonmotor, and autonomic symptoms, resulting from putaminal and cerebellar degeneration and associated with glial cytoplasmic inclusions enriched with α-synuclein in oligodendrocytes and neurons. Although symptomatic treatment of MSA can provide significant improvements in quality of life, the benefit is often partial, limited by adverse effects, and fails to treat the underlying cause. Consistent with the multisystem nature of the disease and evidence that motor symptoms, autonomic failure, and depression drive patient assessments of quality of life, treatment is best achieved through a coordinated multidisciplinary approach driven by the patient's priorities and goals of care. Research into disease-modifying therapies is ongoing with a particular focus on synuclein-targeted therapies among others. This review focuses on both current management and emerging therapies for this devastating disease.

An update on MSA: premotor and non-motor features open a window of opportunities for early diagnosis and intervention

In this review, we describe the wide clinical spectrum of features that can be seen in multiple system atrophy (MSA) with a focus on the premotor phase and the non-motor symptoms providing an up-to-date overview of the current understanding in this fast-growing field. First, we highlight the non-motor features at disease onset when MSA can be indistinguishable from pure autonomic failure or other chronic neurodegenerative conditions. We describe the progression of clinical features to aid the diagnosis of MSA early in the disease course. We go on to describe the levels of diagnostic certainty and we discuss MSA subtypes that do not fit into the current diagnostic criteria, highlighting the complexity of the disease as well as the need for revised diagnostic tools. Second, we describe the pathology, clinical description, and investigations of cardiovascular autonomic failure, urogenital and sexual dysfunction, orthostatic hypotension, and respiratory and REM-sleep behavior disorders, which may precede the motor presentation by months or years. Their presence at presentation, even in the absence of ataxia and parkinsonism, should be regarded as highly suggestive of the premotor phase of MSA. Finally, we discuss how the recognition of the broader spectrum of clinical features of MSA and especially the non-motor features at disease onset represent a window of opportunity for disease-modifying interventions.

Multiple system atrophy

Multiple system atrophy (MSA) is a sporadic, adult-onset, relentlessly progressive neurodegenerative disorder, clinically characterized by various combinations of autonomic failure, parkinsonism and ataxia. The neuropathological hallmark of MSA are glial cytoplasmic inclusions consisting of misfolded α-synuclein. Selective atrophy and neuronal loss in striatonigral and olivopontocerebellar systems underlie the division into two main motor phenotypes of MSA-parkinsonian type and MSA-cerebellar type. Isolated autonomic failure and REM sleep behavior disorder are common premotor features of MSA. Beyond the core clinical symptoms, MSA manifests with a number of non-motor and motor features. Red flags highly specific for MSA may provide clues for a correct diagnosis, but in general the diagnostic accuracy of the second consensus criteria is suboptimal, particularly in early disease stages. In this chapter, the authors discuss the historical milestones, etiopathogenesis, neuropathological findings, clinical features, red flags, differential diagnosis, diagnostic criteria, imaging and other biomarkers, current treatment, unmet needs and future treatments for MSA.

Therapeutic Management of the Overlapping Syndromes of Atypical Parkinsonism

Progressive supranuclear palsy, corticobasal degeneration and multiple system atrophy account for approximately 10% of neurodegenerative parkinsonism. Considerable clinical overlap exists between these disorders that extends to features considered characteristic of each disease. Clinical diagnostic criteria have attempted to increase the accuracy of clinical diagnosis as accurate diagnosis is necessary to inform prognosis and to facilitate the recognition of disease-modifying treatments. Currently no such treatment exists. Nevertheless, many clinical trials aiming to change the natural history of these diseases are ongoing. The spread and accumulation of abnormal proteins are among the pathophysiological mechanisms targeted. For the time being, however, only symptomatic treatment is available. Levodopa is used to treat parkinsonism, but patients usually show a poor or transient response. Amantadine is also used in practice for the same indication. Botulinum toxin can alleviate focal dystonic manifestations. Addressing non-motor manifestations is limited by the potential of available drugs to impact on other aspects of the disease. Most of the new symptomatic formulations under study are focused on orthostatic hypotension in multiple system atrophy. Exercise, occupational, physical, and speech therapy and psychotherapy should always accompany pharmacological approaches.

Effects of Multi-Session Repetitive Transcranial Magnetic Stimulation on Motor Control and Spontaneous Brain Activity in Multiple System Atrophy: A Pilot Study

Background: Impaired motor control is one of the most common symptoms of multiple system atrophy (MSA). It arises from dysfunction of the cerebellum and its connected neural networks, including the primary motor cortex (M1), and is associated with altered spontaneous (i.e., resting-state) brain network activity. Non-invasive repetitive transcranial magnetic stimulation (rTMS) selectively facilitates the excitability of supraspinal networks. Repeated rTMS sessions have been shown to induce long-term changes to both resting-state brain dynamics and behavior in several neurodegenerative diseases. Here, we hypothesized that a multi-session rTMS intervention would improve motor control in patients with MSA, and that such improvements would correlate with changes in resting-state brain activity. Methods: Nine participants with MSA received daily sessions of 5 Hz rTMS for 5 days. rTMS targeted both the cerebellum and the bilateral M1. Before and within 3 days after the intervention, motor control was assessed by the motor item of the Unified Multiple System Atrophy Rating Scale (UMSARS). Resting-state brain activity was recorded by blood-oxygen-level dependency (BOLD) functional magnetic resonance imaging. The "complexity" of resting-state brain activity fluctuations was quantified within seven well-known functional cortical networks using multiscale entropy, a technique that estimates the degree of irregularity of the BOLD time-series across multiple scales of time. Results: The rTMS intervention was well-attended and was not associated with any adverse events. Average motor scores were lower (i.e., better performance) following the rTMS intervention as compared to baseline (t8 = 2.3, p = 0.003). Seven of nine participants exhibited such pre-to-post intervention improvements. A trend toward an increase in resting-state complexity was observed within the motor network (t8 = 1.86, p = 0.07). Participants who exhibited greater increases in motor network resting-state complexity demonstrated greater improvement in motor control (r2= 0.72, p = 0.004). Conclusion: This pilot study demonstrated that a five-session rTMS intervention targeting the cerebellum and bilateral M1 is feasible and safe for those with MSA. More definitive, well-controlled trials are warranted to confirm our preliminary results that rTMS may alleviate the severity of motor dysfunction and modulate the multiscale dynamics of motor network brain activity.