Cognition in multiple system atrophy: a single-center cohort study

Multiple system atrophy: an update and emerging directions of biomarkers and clinical trials

Multiple system atrophy is a rare, debilitating, adult-onset neurodegenerative disorder that manifests clinically as a diverse combination of parkinsonism, cerebellar ataxia, and autonomic dysfunction. It is pathologically characterized by oligodendroglial cytoplasmic inclusions containing abnormally aggregated α-synuclein. According to the updated Movement Disorder Society diagnostic criteria for multiple system atrophy, the diagnosis of clinically established multiple system atrophy requires the manifestation of autonomic dysfunction in combination with poorly levo-dopa responsive parkinsonism and/or cerebellar syndrome. Although symptomatic management of multiple system atrophy can substantially improve quality of life, therapeutic benefits are often limited, ephemeral, and they fail to modify the disease progression and eradicate underlying causes. Consequently, effective breakthrough treatments that target the causes of disease are needed. Numerous preclinical and clinical studies are currently focusing on a set of hallmarks of neurodegenerative diseases to slow or halt the progression of multiple system atrophy: pathological protein aggregation, synaptic dysfunction, aberrant proteostasis, neuronal inflammation, and neuronal cell death. Meanwhile, specific biomarkers and measurements with higher specificity and sensitivity are being developed for the diagnosis of multiple system atrophy, particularly for early detection of the disease. More intriguingly, a growing number of new disease-modifying candidates, which can be used to design multi-targeted, personalized treatment in patients, are being investigated, notwithstanding the failure of most previous attempts.

Emotion Recognition in Multiple System Atrophy: An Exploratory Eye-Tracking Study

OBJECTIVE

Emotional processing is a core feature of social interactions and has been well studied in patients with idiopathic Parkinson's disease (PD), albeit with contradictory.

RESULTS

. However, these studies excluded patients with atypical parkinsonism, such as multiple system atrophy (MSA). The objective of this exploratory study was to provide better insights into emotion processing in patients with MSA using eye tracking data.

METHODS

We included 21 MSA patients, 15 PD patients and 19 matched controls in this study. Participants performed a dynamic and a static emotion recognition task, and gaze fixations were analyzed in different areas of interest. Participants underwent neuropsychological testing and assessment of depression and alexithymia.

RESULTS

MSA patients were less accurate in recognizing anger than controls (p = 0.02) and had overall fewer fixations than controls (p = 0.001). In the static task, MSA patients had fewer fixations (p < 0.001) and a longer time to first fixation (p = 0.026) on the eye region. Furthermore, MSA patients had a longer fixation duration overall than PD patients (p = 0.004) and longer fixations on the nose than controls (p = 0.005). Alexithymia scores were higher in MSA patients compared to controls (p = 0.038).

CONCLUSION

This study demonstrated impaired recognition of anger in MSA patients compared to HCs. Fewer and later fixations on the eyes along with a center bias suggest avoidance of eye contact, which may be a characteristic gaze behavior in MSA patients.

[Cognitive impairment in multiple system atrophy - exclusion criteria or an integral part of the clinical picture?]

Multiple system atrophy (MSA) is a severe, orphan disease characterized by a steady increase in symptoms of parkinsonism, cerebellar disorders, and autonomic failure. In addition to autonomic failure, which is considered the defining symptom of this type of atypical parkinsonism, there are a range of other non-motor clinical manifestations, such as sleep disorders, pain syndrome, anxiety-depressive disorders, cognitive impairment (CI). CI, especially severe CI, has long been considered as a distinctive feature of MCA. Recently, there have been many clinical studies with pathomorphological or neuroimaging confirmation, indicating a high prevalence of cognitive disorders in MCA. In this article, we discuss the pathogenetic mechanisms of the development of MCA and CI in MCA, as well as the range of clinical manifestations of cognitive dysfunction.

Quantitative cellular changes in multiple system atrophy brains

Multiple system atrophy (MSA) is a neurodegenerative disorder characterised by a combined symptomatology of parkinsonism, cerebellar ataxia, autonomic failure and corticospinal dysfunction. In brains of MSA patients, the hallmark lesion is the aggregation of misfolded alpha-synuclein in oligodendrocytes. Even though the underlying pathological mechanisms remain poorly understood, the evidence suggests that alpha-synuclein aggregation in oligodendrocytes may contribute to the neurodegeneration seen in MSA. The primary aim of this review is to summarise the published stereological data on the total number of neurons and glial cell subtypes (oligodendrocytes, astrocytes and microglia) and volumes in brains from MSA patients. Thus, we include in this review exclusively the reports of unbiased quantitative data from brain regions including the neocortex, nuclei of the cerebrum, the brainstem and the cerebellum. Furthermore, we compare and discuss the stereological results in the context of imaging findings and MSA symptomatology. In general, the stereological results agree with the common neuropathological findings of neurodegeneration and gliosis in brains from MSA patients and support a major loss of nigrostriatal neurons in MSA patients with predominant parkinsonism (MSA-P), as well as olivopontocerebellar atrophy in MSA patients with predominant cerebellar ataxia (MSA-C). Surprisingly, the reports indicate only a minor loss of oligodendrocytes in sub-cortical regions of the cerebrum (glial cells not studied in the cerebellum) and negligible changes in brain volumes. In the past decades, the use of stereological methods has provided a vast amount of accurate information on cell numbers and volumes in the brains of MSA patients. Combining different techniques such as stereology and diagnostic imaging (e.g. MRI, PET and SPECT) with clinical data allows for a more detailed interdisciplinary understanding of the disease and illuminates the relationship between neuropathological changes and MSA symptomatology.

Comparison of tandospirone and escitalopram as a symptomatic treatment in Multiple System Atrophy-cerebellar ataxia: An open-label, non-controlled, 4 weeks observational study

BACKGROUND

Multiple system atrophy (MSA) is a neurodegenerative disorder characterized by autonomic failure and motor dysfunction in parkinsonism and/or cerebellar ataxia. Patients with MSA usually present with depression and anxiety symptoms. This observational study of patients with MSA-cerebellar subtype (MSA-C) with subthreshold depression/anxiety symptoms aimed to compare the efficacy of escitalopram oxalate (an antidepressant drug) and tandospirone citrate (an anxiolytic drug).

METHODS

Fifty-six MSA-C patients were included, with 28 patients in each treatment group. One group received escitalopram oxalate 10 mg/day and the other group received tandospirone citrate 30 mg/day. The patients were evaluated at baseline and after 4 weeks. Several psychiatric and neurological tests were performed, including the Hamilton Anxiety Rating Scale (HAMA), Hamilton Depression Rating Scale (HAMD), Scale for the Assessment and Rating of Ataxia (SARA), and the Scale for Outcomes in Parkinson's Disease for Autonomic Symptoms (SCOPA-AUT). Furthermore, post-void residual urine volume (PVR) and blood pressure were measured.

RESULTS

There was a more substantial reduction in the HAMA/HAMD, scores of stance, finger tracking, and finger nose test in the SARA, and PVR in the tandospirone group. There was a more substantial reduction in scores of dysuria, light-headed when standing up, syncope and hyperhidrosis in the SCOPA-AUT in the escitalopram group (p's < 0.05).

CONCLUSIONS

Tandospirone citrate was more effective in improving depression/anxiety and some cerebellar ataxia symptoms, whereas escitalopram was more effective in improving some autonomic symptoms in MSA-C patients over a short-term period in an open-label observational study without a control group. Further research is needed to evaluate the long-term effects of tandospirone and escitalopram in MSA-C in long-term placebo controlled trials.

Depression in dementia with Lewy bodies: a critical update

Depression with an estimated prevalence of 35% is a frequent manifestation of dementia with Lewy bodies (DLB), having negative effects on cognitive performance and life expectancy, yet the underlying neurobiology is poorly understood and most likely heterogeneous. Depressive symptoms in DLB can occur during the clinical course and, together with apathy, is a common prodromal neuropsychiatric symptom of this neurocognitive disorder in the group of Lewy body synucleinopathies. There are no essential differences in the frequency of depression in DLB and Parkinson disease-dementia (PDD), while its severity is up to twice as high as in Alzheimer disease (AD). Depression in DLB that is frequently underdiagnosed and undertreated, has been related to a variety of pathogenic mechanisms associated with the basic neurodegenerative process, in particular dysfunctions of neurotransmitter systems (decreased monoaminergic/serotonergic, noradrenergic and dopaminergic metabolism), α-synuclein pathology, synaptic zinc dysregulation, proteasome inhibition, gray matter volume loss in prefrontal and temporal areas as well as dysfunction of neuronal circuits with decreased functional connectivity of specific brain networks. Pharmacotherapy should avoid tricyclic antidepressants (anticholinergic adverse effects), second-generation antidepressants being a better choice, while modified electroconvulsive therapy, transcranial magnetic stimulation therapy and deep brain stimulation may be effective for pharmacotherapy-resistant cases. Since compared to depression in other dementias like Alzheimer disease and other parkinsonian syndromes, our knowledge of its molecular basis is limited, and further studies to elucidate the heterogeneous pathogenesis of depression in DLB are warranted.

Mild cognitive impairment in multiple system atrophy: a brain network disorder

Cognitive impairment (CI), previously considered as a non-supporting feature of multiple system atrophy (MSA), according to the second consensus criteria, is not uncommon in this neurodegenerative disorder that is clinically characterized by a variable combination of autonomic failure, levodopa-unresponsive parkinsonism, motor and cerebellar signs. Mild cognitive impairment (MCI), a risk factor for dementia, has been reported in up to 44% of MSA patients, with predominant impairment of executive functions/attention, visuospatial and verbal deficits, and a variety of non-cognitive and neuropsychiatric symptoms. Despite changing concept of CI in this synucleinopathy, the underlying pathophysiological mechanisms remain controversial. Recent neuroimaging studies revealed volume reduction in the left temporal gyrus, and in the dopaminergic nucleus accumbens, while other morphometric studies did not find any gray matter atrophy, in particular in the frontal cortex. Functional analyses detected decreased functional connectivity in the left parietal lobe, bilateral cuneus, left precuneus, limbic structures, and cerebello-cerebral circuit, suggesting that structural and functional changes in the subcortical limbic structures and disrupted cerebello-cerebral networks may be associated with early cognitive decline in MSA. Whereas moderate to severe CI in MSA in addition to prefrontal-striatal degeneration is frequently associated with cortical Alzheimer and Lewy co-pathologies, neuropathological studies of the MCI stage of MSA are unfortunately not available. In view of the limited structural and functional findings in MSA cases with MCI, further neuroimaging and neuropathological studies are warranted in order to better elucidate its pathophysiological mechanisms and to develop validated biomarkers as basis for early diagnosis and future adequate treatment modalities in order to prevent progression of this debilitating disorder.

Characteristics of Mild Cognitive Impairment and Associated Factors in MSA Patients

Mild cognitive impairment (MCI) in multiple-system atrophy (MSA) patients is common but remains poorly characterized, and the related factors are unclear. This retrospective study included 200 consecutive patients with a clinical diagnosis of possible or probable MSA, 102 MSA patients with MCI (MSA-MCI), and 98 MSA patients with normal cognition (MSA-NC). Cognitive profiles were compared between MSA-MCI and MSA-NC patients using the MoCA. In addition, demographic as well as major motor and nonmotor symptom differences were compared between MSA-MCI and MSA-NC patients. The median MMSE score was 26 points. Overall, MSA-MCI was observed in 51% of patients, with predominant impairment in visuospatial, executive, and attention functions compared with MSA-NC patients. MSA-MCI patients were older (p = 0.015) and had a later onset age (p = 0.024) and a higher frequency of hypertension, motor onset, and MSA with the predominant parkinsonism (MSA-P) phenotype than MSA-NC patients. The positive rate of orthostatic hypotension (OH) in MSA-MCI patients was significantly decreased and depression/anxiety was significantly increased compared with MSA-NC patients (p = 0.004). Multivariate logistic analysis showed that motor onset was independently associated with MCI in MSA patients. MSA-MCI patients had impairment in visuospatial, executive, and attention functions. More prominent memory impairment was observed in MSA-P than in MSA-C patients. Motor onset was independently associated with MCI in MSA patients. MCI was commonly presented in MSA with more prominent memory impairment in MSA-P. Future follow-up studies are warranted to identify more factors that influence cognitive impairment in MSA.

The characteristic of nonmotor symptoms with different phenotypes and onsets in multiple system atrophy patients

OBJECTIVES

The characteristic of nonmotor symptoms in patients with multiple system atrophy (MSA) has varied among previous studies. The objective was to investigatethe nonmotor characteristics in MSA patients with different phenotypes, sex and different onset patterns.

METHODS

We performed a retrospective review of 1492 MSA patients. All cases were evaluatedby neurologists and assessed with motormanifestations, nonmotor symptoms, auxiliary examinationand brain MRI scans.

RESULTS

Multiple system atrophy-cerebellar ataxia (MSA-C) was the predominant phenotype in 998 patients. Average age of onset (56.8 ± 9.2 years) was earlier, the disease duration (2.4 ± 2.2 year) was shorter and brain MRI abnormalities (49.2 %) were more frequently in MSA-C (P < 0.001). Multiple system atrophy-parkinsonism (MSA-P) patients were more likely to have nonmotor symptoms. After adjusted significant parameters, urinary dysfunction (OR 1.441, 95 %CI = 1.067-1.946, P = 0.017), constipation (OR 1.482, 95 %CI = 1.113-1.973, P = 0.007), cognitive impairment (OR 1.509, 95 %CI = 1.074-2.121, P = 0.018) and drooling (OR 2.095, 95 %CI = 1.248-3.518, P = 0.005) were associated with the MSA-P phenotype. Males were more likely to have orthostatic hypotension, urinary dysfunction, sexual dysfunction, drooling and females in constipation and probable RBD. In different onset patterns, constipation (59.2 %) and probable RBD (28.4 %) were more frequently in autonomiconset pattern.

CONCLUSIONS

MSA-C is the predominant phenotype in Chinese patients, while many nonmotor symptoms are more common in MSA-P phenotype. Patients with different sex and onset patterns have different nonmotor characteristics. The different clinical features identified could help the physician counseling of MSA patients more easily and more accurately.

Morphological differences between the two major subtypes of multiple system atrophy with cognitive impairment

OBJECTIVE

To compare the neuropathology between two types of multiple system atrophy - parkinsonism-predominant (MSA-P) and cerebellar ataxia-predominant (MSA-C) with cognitive impairment.

MATERIAL & METHODS

35 cases of MSA-P (mean age at death 60.5 ± 7.8 years) and 15 cases of MSA-C (mean age at death 61.3 ± 6.8 years), 35.% of which associated with mild to moderate cognitive impairment and one with severe dementia, were examined neuropathologically with semiquantitative evaluation of both α-synuclein and Alzheimer pathologies, including cerebral amyloid angiopathy (CAA) and other co-pathologies.

RESULTS

While the mean age at death of both MSA subgroups was similar, the age at onset and duration of disease were slightly higher in the MSA-C group. In line with the classification, the αSyn pathology glial and neuronal inclusions in both the cortex and brainstem were significantly higher in the MSA-P group. With regard to the Alzheimer disease pathology, tau load in cases with mild to moderate cognitive impairment was slightly but not significantly higher in the MSA-P group, one with severe dementia showing fully developed Alzheimer co-pathology, while the amyloid-β (Aβ) load including the CAA was higher in the MSA-C group. The presence of Lewy co-pathology in this series (20%), being similar to that of other MSA cohorts, was more frequent in MSA cases with mild to severe cognitive impairment, but did not differ between the two subgroups and seems not essentially important for MCI in MSA.

CONCLUSIONS

In agreement with previous clinical studies that reported more severe cognitive dysfunction in patients with MSA-P, the present neuropathological study showed increased tau pathology in MSA-P and one with severe Alzheimer co-pathology, but only slightly increased amyloid pathology in the MSA-C group. Lewy co-pathology was more frequent in MSA-P cases with cognitive decline. In view of the limited data about the pathobiological basis of cognitive impairment in MSA, further studies to elucidate the differences between the two phenotypes are urgently needed.

Multiple System Atrophy: Advances in Diagnosis and Therapy

This review summarizes improvements in understanding the pathophysiology and early clinical symptoms of multiple system atrophy (MSA) and advancements in diagnostic methods and disease-modifying therapies for the condition. In 2022, the Movement Disorder Society proposed new diagnostic criteria to develop disease-modifying therapies and promote clinical trials of MSA since the second consensus was proposed in 2008. Regarding pathogenesis, cutting-edge findings have accumulated on the interactions of α-synuclein, neuroinflammation, and oligodendroglia with neurons. In neuroimaging, introducing artificial intelligence, machine learning, and deep learning has notably improved diagnostic accuracy and individual analyses. Advancements in treatment have also been achieved, including immunotherapy therapy against α-synuclein and serotonin-targeted and mesenchymal stem cell therapies, which are thought to affect several aspects of the disease, including neuroinflammation. The accelerated progress in clarifying the pathogenesis of MSA over the past few years and the development of diagnostic techniques for detecting early-stage MSA are expected to facilitate the development of disease-modifying therapies for one of the most intractable neurodegenerative diseases.

Orthostatic Hypotension in Multiple System Atrophy: Related Factors and Disease Prognosis

BACKGROUND

Multiple system atrophy (MSA) is a rare neurodegenerative disease characterized by Parkinsonism, ataxia, and autonomic nervous failure. Orthostatic hypotension (OH) is the main feature of central vascular autonomic failure in MSA.

OBJECTIVE

The study aimed elucidate the effects of OH on cognitive function, disease milestones, and survival.

METHODS

A total of 444 patients with clinically established MSA were enrolled. Mild and severe OH were defined as a decrease in systolic blood pressure (SBP)/diastolic blood pressure (DBP) >20/10 mmHg and SBP/DBP ≥30/15 mmHg, respectively.

RESULTS

In this study, 215 MSA patients presented without OH, 88 had mild OH, and 141 had severe OH. The proportion of MSA-C in the severe OH subgroup was significantly higher than that in the subgroup without OH (95/46 vs. 113/102, p = 0.021). The UMSARS I score and the frequency of supine hypertension (SH) in patients with OH were significantly higher than those in patients without OH (16.22 vs. 16.89 vs. 14.60, p < 0.001; 77/64 vs. 29/59 vs. 32/183, p < 0.001). Factors related to the severity of OH included sex (OR, 0.65; p = 0.031), onset age (OR, 0.98; p = 0.029), and SH (OR, 0.21; p < 0.001). The median survival time of patients with severe OH was significantly lower than that of patients without OH (6.79 vs. 8.13 years, p = 0.001). Consistently, Cox survival analysis found that compared with patients without OH, patients with severe OH had a significantly increased risk of death (OR, 2.22; p < 0.001).

CONCLUSION

Our large cohort study of MSA provides additional evidence for the negative impact of severe OH on survival.

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.

Prevalence and Clinical Characteristics of Dementia and Cognitive Impairment in Multiple System Atrophy: A Systematic Review and Meta-Analysis

BACKGROUND

Cognitive impairment is a clinical feature of multiple system atrophy (MSA). However, the prevalence and factors influencing the prevalence of cognitive impairment and dementia in MSA patients remain unclear.

OBJECTIVE

We aim to provide an estimate of the prevalence of cognitive impairment and dementia in patients with MSA and to evaluate the possible effect of demographic, clinical and methodological factors on the prevalence.

METHODS

We systematically searched the PubMed, Embase, and Web of science databases to identify studies that report the prevalence of cognitive impairment or dementia in MSA published up to February 2022. We computed the estimates of the pooled prevalence using random-effects models. Heterogeneity was investigated by subgroup analyses and meta-regression. Differences between MSA patients with and without cognitive impairment in demographic and clinical features were explored.

RESULTS

A total of 23 studies comprising 2064 MSA patients were included in meta-analysis. The pooled prevalence of cognitive impairment in MSA patients was 37% (95% CI: 29% -45%), the prevalence of dementia was 11% (95% CI: 7% -15%). The subgroup analyses showed the prevalence of dementia in pathologically-confirmed MSA was 7% (95% CI: 0% -12%), in clinically diagnosed MSA was 14% (95% CI: 10% -18%). Cognitive impairment in MSA patients was associated with older age, lower education, longer disease duration and more severe motor symptoms.

CONCLUSION

Cognitive impairment is a common non-motor symptom in MSA. Dementia can develop in a few patients with MSA as well, but usually in the late stage.

Determinants of cognitive impairment in multiple system atrophy: Clinical and genetic study

INTRODUCTION

Classically, cognitive impairment (CI) was not considered as a paramount feature of multiple system atrophy(MSA) in both parkinsonian(MSA-P) and cerebellar(MSA-C) motor-subtypes. Yet, growing evidence indicates currently the commonness of such deficits among MSA patients in different populations. Our aim was to evaluate the cognitive profile of MSA Tunisian patients and to analyze the underlying clinical and genetic determinants.

METHODS

In a retrospective cross-sectional study, clinically-diagnosed MSA patients were included. All subjects underwent clinical and neuropsychological assessments to characterize their cognitive profile. The associations with their APOE genotype status were analyzed. Determinant of CI were specified.

RESULTS

We included 71 MSA patients. Female gender(sex-ratio = 0.65) and MSA-P subtype(73%) were predominant. Mean age of disease onset was 59.1years. CI was found in 85.7% of patients(dementia in 12.7% and Mild cognitive impairment(MCI) in 73% of patients mainly of multiple-domain amnestic type(37.3%)). Mean MMSE score was lower among MSA-P compared to MSA-C(23.52 vs. 26.47;p = 0.027). Higher postural instability gait disorder(PIGD) and MDS-UPDRS-III scores were noted in demented MSA patients(p = 0.019;p = 0.015 respectively). The main altered cognitive domain was attention(64.8%). Executive functions and mood disorders were more affected in MSA-P(p = 0.029,p = 0.035 respectively). Clinical and neurophysiological study of dysautonomia revealed no differences across cognitive subtypes. APOE genotyping was performed in 51 MSA patients with available blood samples. Those carrying APOEε4 had 1.32 fold higher risk to develop CI, with lower MMSE score(p = 0.0001). Attention and language were significantly altered by adjusting the p value to APOEɛ4 carriers(p = 0.046 and p = 0.044 respectively). Executive dysfunction was more pronounced among MSA-PAPOEε4 carriers(p = 0.010).

CONCLUSION

In this study, the main determinants of CI in Tunisian MSA patients were MSA-P motor-subtype, mainly of PIGD-phenotype, disease duration and APOEε4 carrying status, defining a more altered cognitive phenotype. This effect mainly concerned executive, attention and language functions, all found to be more impaired in APOEε4 carriers with variable degrees across MSA motor-subtypes.

Prospective CERAD Neuropsychological Assessment in Patients With Multiple System Atrophy

The objective of the study was to characterize the pattern of cognitive dysfunction in patients with multiple system atrophy (MSA) applying a standardized neuropsychological assessment. A total of 20 patients with the diagnosis of probable or possible MSA were enrolled for neuropsychological assessment applying the CERAD plus battery. All patients were tested at baseline and 14/20 patients received additional follow-up assessments (median follow-up of 24 months). Additionally, relationship between cortical thickness values/subcortical gray matter volumes and CERAD subitems was evaluated at baseline in a subgroup of 13/20 patients. Trail Making Test (TMT) was the most sensitive CERAD item at baseline with abnormal performance (z-score < −1.28) in one or both pathological TMT items (TMT-A, TMT-B) in 60% of patients with MSA. Additionally, there was a significant inverse correlation between the volume of the left and the right accumbens area and the TMT A item after adjusting for age (left side: p = 0.0009; right side p = 0.003). Comparing both subtypes, patients with MSA-C had significant lower values in phonemic verbal fluency (p = 0.04) and a trend for lower values in semantic verbal fluency (p = 0.06) compared to MSA-P. Additionally, patients with MSA-C showed significantly worse performance in the TMT-B task (p = 0.04) and a trend for worse performance in the TMT-A task (p = 0.06). Concerning longitudinal follow-up, a significant worsening in the TMT-B (p = 0.03) can be reported in MSA. In conclusion, frontal-executive dysfunction presents the hallmark of cognitive impairment in MSA.

Cognitive and Autonomic Dysfunction in Multiple System Atrophy Type P and C: A Comparative Study

Multiple System Atrophy (MSA) is a rare neurodegenerative disease, clinically defined by a combination of autonomic dysfunction and motor involvement, that may be predominantly extrapyramidal (MSA-P) or cerebellar (MSA-C). Although dementia is generally considered a red flag against the clinical diagnosis of MSA, in the last decade the evidence of cognitive impairment in MSA patients has been growing. Cognitive dysfunction appears to involve mainly, but not exclusively, executive functions, and may have different characteristics and progression in the two subtypes of the disease (i.e., MSA-P and MSA-C). Despite continued efforts, combining in-vivo imaging studies as well as pathological studies, the physiopathological bases of cognitive involvement in MSA are still unclear. In this view, the possible link between cardiovascular autonomic impairment and decreased cognitive performance, extensively investigated in PD, needs to be clarified as well. In the present study, we evaluated a cohort of 20 MSA patients (9 MSA-P, 11 MSA-C) by means of a neuropsychological battery, hemodynamic assessment (heart rate and arterial blood pressure) during rest and active standing and bedside autonomic function tests assessed by heart rate variability (HRV) parameters and sympathetic skin response (SSR) in the same experimental session. Overall, global cognitive functioning, as indicated by the MoCA score, was preserved in most patients. However, short- and long-term memory and attentional and frontal-executive functions were moderately impaired. When comparing MSA-P and MSA-C, the latter obtained lower scores in tests of executive functions and verbal memory. Conversely, no statistically significant difference in cardiovascular autonomic parameters was identified between MSA-P and MSA-C patients. In conclusion, moderate cognitive deficits, involving executive functions and memory, are present in MSA, particularly in MSA-C patients. In addition, our findings do not support the role of dysautonomia as a major driver of cognitive differences between MSA-P and MSA-C.

Pre-diagnostic presentations of Multiple System Atrophy case control study in a primary care dataset

BACKGROUND

We here report the pre-diagnostic clinical presentations of patients with Multiple System Atrophy (MSA) from analysis of a large routine clinical care database.

METHODS

Data were extracted from a primary care database in the German healthcare system for the period between January 2000 and December 2020. We identified 250 patients with new diagnosis of MSA and 250 controls matched for age, sex, and index year. Logistic regression analyses were conducted to assess association between MSA and predefined diagnoses.

RESULTS

The greatest rate increase in the 2 years preceding diagnosis of MSA was seen for hypotension and balance impairment but rates of memory problems, urinary dysfunction, dizziness and depression rates were also markedly increased, and ataxia was solely identified in those with a later diagnosis of MSA. Up to 5 years before diagnosis similar patterns were seen, but >5 years before diagnosis only depression rates were increased with a trend for increase in constipation.

CONCLUSIONS

Presentations that were significantly more common in patients with MSA in the pre-diagnostic phase than in controls were autonomic complaints such as postural hypotension, urinary and bowel dysfunction, and early balance impairment. However, the study also highlights that memory complaints and depression may be early features of MSA years before diagnosis.

Cognitive Syndromes Associated With Movement Disorders

PURPOSE OF REVIEW

This article reviews the recognition and management of cognitive syndromes in movement disorders, including those with parkinsonism, chorea, ataxia, dystonia, and tremor.

RECENT FINDINGS

Cognitive and motor syndromes are often intertwined in neurologic disorders, including neurodegenerative diseases such as Parkinson disease, atypical parkinsonian syndromes, Huntington disease, and other movement disorders. Cognitive symptoms often affect attention, working memory, and executive and visuospatial functions preferentially, rather than language and memory, but heterogeneity can be seen in the various movement disorders. A distinct cognitive syndrome has been recognized in patients with cerebellar syndromes. Appropriate recognition and screening for cognitive changes in movement disorders may play a role in achieving accurate diagnoses and guiding patients and their families regarding progression and management decisions.

SUMMARY

In the comprehensive care of patients with movement disorders, recognition of cognitive syndromes is important. Pharmacologic treatments for the cognitive syndromes, including mild cognitive impairment and dementia, in these movement disorders lag behind the therapeutics available for motor symptoms, and more research is needed. Patient evaluation and management require a comprehensive team approach, often linking neurologists as well as neuropsychologists, psychologists, psychiatrists, social workers, and other professionals.

The Profile and Evolution of Neuropsychiatric Symptoms in Multiple System Atrophy: Self- and Caregiver Report

OBJECTIVE

Recent research shows that patients with multiple system atrophy (MSA) have significant cognitive and neuropsychiatric comorbidities that can color the clinical presentation of the disease and affect their quality of life. The aims of this study were to determine the neuropsychiatric profile in a cohort of patients with the parkinsonian type of MSA (MSA-P) and their dynamic changes over a 1-year follow-up period and to compare rates of neuropsychiatric symptoms (NPSs) reported by caregivers and the patients themselves.

METHODS

Forty-seven patients were assessed at baseline; of these, 25 were assessed again after 1 year. NPS assessment tools included the Neuropsychiatric Inventory (NPI), the Beck Depression Inventory, the Hamilton Depression Rating Scale, the Hamilton Anxiety Rating Scale, and the Apathy Evaluation Scale.

RESULTS

The prevalence of NPSs in patients with MSA-P was very high, with depression, sleep disturbances, apathy, and anxiety being the most frequently occurring features. The evolution of NPSs was found to be independent of motor, autonomic, and cognitive symptoms. None of the scales measuring NPSs, including the NPI, were capable of detecting changes over the 1-year follow-up period. Although the overall prevalence of depression, apathy, and anxiety obtained from caregivers and the patients themselves was similar, reports from these two sources cannot be considered interchangeable.

CONCLUSIONS

The progression of neuropsychiatric symptoms was not a subject of rapid change in MSA-P, in contrast to the observed motor, autonomic, and cognitive deterioration. These findings suggest the need to investigate the utility of available instruments in capturing the evolution of NPSs in MSA over time.

Optimization of cognitive assessment in Parkinsonisms by applying artificial intelligence to a comprehensive screening test

The assessment of cognitive deficits is pivotal for diagnosis and management in patients with parkinsonisms. Low levels of correspondence are observed between evaluations assessed with screening cognitive tests in comparison with those assessed with in-depth neuropsychological batteries. A new tool, we named CoMDA (Cognition in Movement Disorders Assessment), was composed by merging Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and Frontal Assessment Battery (FAB). In total, 500 patients (400 with Parkinson’s disease, 41 with vascular parkinsonism, 31 with progressive supranuclear palsy, and 28 with multiple system atrophy) underwent CoMDA (level 1–L1) and in-depth neuropsychological battery (level 2–L2). Machine learning was developed to classify the CoMDA score and obtain an accurate prediction of the cognitive profile along three different classes: normal cognition (NC), mild cognitive impairment (MCI), and impaired cognition (IC). The classification accuracy of CoMDA, assessed by ROC analysis, was compared with MMSE, MoCA, and FAB. The area under the curve (AUC) of CoMDA was significantly higher than that of MMSE, MoCA and FAB (p < 0.0001, p = 0.028 and p = 0.0007, respectively). Among 15 different algorithmic methods, the Quadratic Discriminant Analysis algorithm (CoMDA-ML) showed higher overall-metrics performance levels in predictive performance. Considering L2 as a 3-level continuous feature, CoMDA-ML produces accurate and generalizable classifications: micro-average ROC curve, AUC = 0.81; and AUC = 0.85 for NC, 0.67 for MCI, and 0.83 for IC. CoMDA and COMDA-ML are reliable and time-sparing tools, accurate in classifying cognitive profile in parkinsonisms.

This study has been registered on ClinicalTrials.gov (NCT04858893).

Heterogeneity of Multiple System Atrophy: An Update

Multiple system atrophy (MSA) is a fatal, rapidly progressing neurodegenerative disease of uncertain etiology, clinically characterized by various combinations of Levodopa unresponsive parkinsonism, cerebellar, autonomic and motor dysfunctions. The morphological hallmark of this α-synucleinopathy is the deposition of aberrant α-synuclein in both glia, mainly oligodendroglia (glial cytoplasmic inclusions /GCIs/) and neurons, associated with glioneuronal degeneration of the striatonigral, olivopontocerebellar and many other neuronal systems. Typical phenotypes are MSA with predominant parkinsonism (MSA-P) and a cerebellar variant (MSA-C) with olivocerebellar atrophy. However, MSA can present with a wider range of clinical and pathological features than previously thought. In addition to rare combined or “mixed” MSA, there is a broad spectrum of atypical MSA variants, such as those with a different age at onset and disease duration, “minimal change” or prodromal forms, MSA variants with Lewy body disease or severe hippocampal pathology, rare forms with an unusual tau pathology or spinal myoclonus, an increasing number of MSA cases with cognitive impairment/dementia, rare familial forms, and questionable conjugal MSA. These variants that do not fit into the current classification of MSA are a major challenge for the diagnosis of this unique proteinopathy. Although the clinical diagnostic accuracy and differential diagnosis of MSA have improved by using combined biomarkers, its distinction from clinically similar extrapyramidal disorders with other pathologies and etiologies may be difficult. These aspects should be taken into consideration when revising the current diagnostic criteria. This appears important given that disease-modifying treatment strategies for this hitherto incurable disorder are under investigation.

Cognition in Patients With Multiple System Atrophy (MSA) and Its Neuroimaging Correlation: A Prospective Case-Control Study

Objective Cognition has been reported to be involved in patients with multiple system atrophy (MSA), although initially it was considered an exclusion in the diagnosis of MSA. We assessed cognition in these patients and compared it with age and education matched healthy controls and correlated with the gray matter volume using voxel-based morphometry (VBM). Materials and methods This was a prospective, case-control, single-center study. Thirty patients with MSA (20 MSA-C (cerebellar variant) and 10 MSA-P (Parkinsonian variant)) and 25 age- and educational level-matched healthy controls were included. All the patients and controls underwent detailed neuropsychological tests and MRI brain. A battery of neuropsychological tests like Stroop test, digit span forward and backward, digit symbol substitution time test, animal naming test, color trail test and auditory verbal learning test were used to assess the various domain of cognition, which include mainly attention, executive function, memory, new learning, mental and motor speed. The gray matter volume was determined using VBM and correlated with neuropsychological scores. Results Attention, execution, verbal and visual memory, verbal fluency, and new learning were impaired in patients with MSA. MSA-P had more impairment in motor and mental speed, working memory, executive functions, and focused attention compared to MSA-C. Patients with MSA-C had more impairment in new learning, immediate recall, verbal fluency, and sustained attention compared to MSA-P. However, it was not statistically significant. There was a significant correlation between the various cognitive domains and atrophy of frontotemporal cortical areas, insula, caudate, thalamus, and cerebellum. Conclusion Cognition is impaired in patients with MSA-C and MSA-P and is likely due to the neurodegenerative process involving the cortical and subcortical structures. Long-term follow-up studies are required to find out the progression of these cognitive changes.

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.

Neuropathology of multiple system atrophy: Kurt Jellinger`s legacy

Multiple System Atrophy (MSA) is a rare, fatal neurodegenerative disorder. Its etiology and exact pathogenesis still remain poorly understood and currently no disease-modifying therapy is available to halt or slow down this detrimental neurodegenerative process. Hallmarks of the disease are α-synuclein rich glial cytoplasmic inclusions (GCIs). Neuropathologically, various degrees of striatonigral degeneration (SND) and olivopontocerebellar atrophy (OPCA) can be observed. Since the original descriptions of this multifaceted disorder, several steps forward have been made to clarify its neuropathological hallmarks and key pathophysiological mechanisms. The Austrian neuropathologist Kurt Jellinger substantially contributed to the understanding of the underlying neuropathology of this disease, to its standardized assessment and to a broad systematical clinic-pathological correlation. On the occasion of his 90th birthday, we reviewed the current state of the art in the field of MSA neuropathology, highlighting Prof. Jellinger’s substantial contribution.

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.

Early autonomic and cognitive dysfunction in PD, DLB and MSA: blurring the boundaries between α-synucleinopathies

Differential diagnosis between Parkinson's disease, dementia with Lewy bodies and multiple system atrophy can be difficult, especially because in early phase they might present with overlapping clinical features. Notably, orthostatic hypotension and cognitive dysfunction are common nonmotor aspects of parkinsonian syndromes and can be both present from the earliest stages of all α-synucleinopathies, indicating a common neurobiological basis in their strong relationship. In view of the increasing awareness about the prevalence of mild cognitive dysfunction in multiple system atrophy, the relevance of autonomic dysfunction in demented parkinsonian patients, the critical role of non-motor symptoms in clustering Parkinson's disease patients and the shift to studying patients in the prodromal phase, we will discuss some intrinsic limitations of current clinical diagnostic criteria, even when applied by movement disorder specialists. In particular, we will focus on the early coexistence of autonomic and cognitive dysfunction in the setting of overt or latent parkinsonism as pitfalls in the differential diagnosis of α-synucleinopathies. As early and accurate diagnosis remains of outmost importance for counselling of patients and timely enrolment into disease-modifying clinical trials, a continuous effort of research community is ongoing to further improve the clinical diagnostic accuracy of α-synucleinopathies.

Neuropathological findings in multiple system atrophy with cognitive impairment

Cognitive impairment (CI), previously considered an exclusion criterium for the diagnosis of multiple system atrophy (MSA) according to the second consensus criteria, is not uncommon in MSA. Mild cognitive impairment (MCI) has been reported in up to 47% of MSA patients, while severe dementia is rare. We related clinical CI with neuropathological findings in 48 autopsy-proven cases of MSA. This retrospective study included 33 parkinsonism predominant MSA (MSA-P), and 15 cerebellar ataxia-predominant MSA (MSA-C) cases (mean age at death 60.5 ± 7.8; range 46-82 years). Cognitive state was assessed from hospital charts, however, without comprehensive neuropsychological testing. Neuropathological examination, in addition to grading of the MSA pathologies, included semiquantitative assessment of Lewy and Alzheimer-related co-pathologies. Their incidence was compared with 143 age-matched controls (mean age 60.5 ± 7.6 years). MCI reported in ten cases (20.8%) was associated with moderate cortical tau pathology in only three; moderate CI in seven patients (14.5%) was associated with cortical amyloid plaques and moderate cortical tau pathology in six each, and one with probable primary age-related tauopathy (PART); a female aged 82 years with severe dementia showed fully developed Alzheimer disease. Cortical amyloid plaques, observed in eight cases, three of them without tau pathology, were associated with clinical MCI, as was cortical Lewy pathology in five. Two cases with cortical Lewy pathology and neuritic Braak stages II and III, and three with Braak stage IV, without cortical Lewy bodies, had shown moderate CI. Cortical Lewy pathology observed in four cases was not associated with clinical CI. 77.1% of the MSA cases were free of Alzheimer-type lesions, compared to 42% of controls; while Lewy pathology in the MSA cohort (22.9%) was significantly higher than in the control group (8.4%) both p < 0.001. Mild-to-moderate CI, reported in 35.3% of MSA patients, being significantly older than those without CI, were frequently associated with cortical Alzheimer (Braak stages III and IV) and Lewy pathologies, while only one with severe dementia had fully developed Alzheimer disease. In view of these findings in a limited series of MSA patients, further studies to elucidate the pathological basis of cognitive impairment in MSA are warranted.