Clinical outcomes of progressive supranuclear palsy and multiple system atrophy

Clinical features and criteria for the diagnosis of progressive supranuclear palsy

SUMMARY The neurofibrillary tau pathology of progressive supranuclear palsy (PSP) has been associated with a number of different clinical syndromes that all ultimately lead to death and disability within 6–10 years. In 1964, Steele, Richardson and Olszewski predicted that the classic clinical syndrome they had described was specific to the topographic distribution of PSP–tau neurodegeneration and that other clinical syndromes may occur if other brain regions were affected. The spectrum of clinical disease related to PSP–tau pathology is indeed broader than 40 years ago. In addition to the classic form of PSP (Richardson’s syndrome), a number of clinical variants caused by the same neurodegenerative process have been identified. These include PSP–Parkinsonism, PSP–corticobasal syndrome, PSP–pure akinesia with gait freezing and PSP–progressive nonfluent aphasia. Here we review the clinical pictures of these syndromes and propose practical diagnostic guidelines to aid the clinician in tackling the challenges presented by the multifaceted condition of PSP–tau pathology.

Gene expression in the Parkinson's disease brain

The study of gene expression has undergone a transformation in the past decade as the benefits of the sequencing of the human genome have made themselves felt. Increasingly, genome wide approaches are being applied to the analysis of gene expression in human disease as a route to understanding the underlying pathogenic mechanisms. In this review, we will summarise current state of gene expression studies of the brain in Parkinson's disease, and examine how these techniques can be used to gain an insight into aetiology of this devastating disorder.

Cognitive impairment in multiple system atrophy: Changing concepts

Multiple system atrophy (MSA) is characterized by a variable combination of cerebellar ataxia, parkinsonism and pyramidal signs associated with autonomic failure. Classically, cognitive impairment was not considered a clinical feature of MSA and dementia was pointed out as an exclusion diagnostic criteria. Based on comprehensive neuropsychological assessment, cognitive impairment was found to be a frequent feature in MSA, and clinically-defined dementia is now reported in 14-16% of cases. This article reviews the current data on cognitive impairment in MSA along with its neuropsychological profile and pathophysiology.

Postural instability, frontotemporal dementia, and ophthalmoplegia: clinicopathological case

A 56-year-old man presented with gait disturbance, personality change, and behavioral disturbances. He subsequently developed falls, postural instability, and axial rigidity. The cognitive problems progressed and he developed aphasia and later eye movement abnormalities. He died after 9 years of disease. Experts discuss the syndromal diagnosis and predict the underlying pathology. The pathological diagnosis is given and clinical learning points are considered.

Infrequent causes of disequilibrium in the adult

This content focuses on some of the less common causes of dizziness in the adult. The diseases have been divided into the 2 broad categories of those causing chronic symptoms and those causing episodic symptoms. Presented here are the unusual causes of chronic disequilibrium in the adult, including bilateral vestibular loss, progressive supranuclear palsy, spinocerebellar ataxias, and mal de debarquement. Also discussed are the unusual causes of episodic disequilibrium in the adult, including psychogenic disequilibrium, vestibular paroxysmia, episodic ataxia, vestibular seizures, and cervicogenic vertigo.

Neuropathology underlying clinical variability in patients with synucleinopathies

Abnormal aggregates of the synaptic protein, α-synuclein, are the dominant pathology in syndromes known as the synucleinopathies. The cellular aggregation of the protein occurs in three distinct types of inclusions in three main clinical syndromes. α-Synuclein deposits in neuronal Lewy bodies and Lewy neurites in idiopathic Parkinson's disease (PD) and dementia with Lewy bodies (DLB), as well as incidentally in a number of other conditions. In contrast, α-synuclein deposits largely in oligodendroglial cytoplasmic inclusions in multiple system atrophy (MSA). Lastly, α-synuclein also deposits in large axonal spheroids in a number of rarer neuroaxonal dystrophies. Disorders are usually defined by their most dominant pathology, but for the synucleinopathies, clinical heterogeneity within the main syndromes is well documented. MSA was originally viewed as three different clinical phenotypes due to different anatomical localization of the lesions. In PD, recent meta-analyses have identified four main clinical phenotypes, and clinicopathological correlations suggest that more severe and more rapid progression of pathology with chronological age, as well as the involvement of additional neuropathologies, differentiates these phenotypes. In DLB, recent large studies show that clinical diagnosis is too insensitive to identify the syndrome itself, although clinicopathological studies suggest variable clinical features occur in the different pathological forms of this syndrome (pure DLB, DLB with Alzheimer's disease (AD), and AD with amygdala predominant Lewy pathology). The recognition of considerable heterogeneity within the synucleinopathy syndromes is important for the identification of factors involved in changing their pathological phenotype.

Visual assessment of dopaminergic degeneration pattern in 123I-FP-CIT SPECT differentiates patients with atypical parkinsonian syndromes and idiopathic Parkinson's disease

The aim of this study was to investigate whether visual assessment of (123)I-N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl)nortropan ((123)I-FP-CIT) single photon emission computed tomography (SPECT) in addition to quantitative analyses can help to differentiate idiopathic Parkinson's disease (PD) from atypical parkinsonian syndromes (APS). From a consecutive series of patients examined with (123)I-FP-CIT SPECT (n = 190) over a three-year period we identified 165 patients with a clinical diagnosis of PD (n = 120) or APS (n = 45). (123)I-FP-CIT SPECT results were analysed visually and quantitatively and compared for PD and APS and for the subgroup of patients with early PD and APS (disease duration <5 years). According to predefined visual patterns of dopaminergic degeneration the results were graded as normal (grade 5) or abnormal (grade 1-4), distinguishing a posterior-anterior degeneration pattern ("egg shape") from a global and severe degeneration pattern ("burst striatum"). Visual assessment of (123)I-FP-CIT SPECT showed significant different dopaminergic degeneration patterns for PD and APS patients. A grade 1 ("burst striatum") degeneration pattern was predominantly associated with APS patients. In contrast to that, a grade 2 (egg shape) degeneration pattern was the characteristic finding in PD patients. In a subgroup of patients with early disease, visual assessment with identification of the burst striatum degeneration pattern provided 90% positive predictive value and 99% specificity for the diagnosis of APS. Quantitative analysis of striatal binding ratios failed to depict these different degeneration patterns in PD and APS patients. Visual assessment of the pattern of dopaminergic loss in (123)I-FP-CIT SPECT shows different patterns of dopaminergic degeneration for PD and APS patients. Therefore, it could provide valuable information to distinguish APS from PD patients, especially in early stages of disease. Within the first 5 years of disease, the occurrence of a burst striatum degeneration pattern has a high positive predictive value of APS.

Glial dysfunction in the pathogenesis of α-synucleinopathies: emerging concepts

Parkinson's disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy (MSA) are adult onset neurodegenerative disorders characterised by prominent intracellular α-synuclein aggregates (α-synucleinopathies). The glial contribution to neurodegeneration in α-synucleinopathies was largely underestimated until recently. However, brains of PD and DLB patients exhibit not only neuronal inclusions such as Lewy bodies or Lewy neurites but also glial α-synuclein aggregates. Accumulating experimental evidence in PD models suggests that astrogliosis and microgliosis act as important mediators of neurodegeneration playing a pivotal role in both disease initiation and progression. In MSA, oligodendrocytes are intriguingly affected by aberrant cytoplasmic accumulation of α-synuclein (glial cytoplasmic inclusions, Papp-Lantos bodies). Converging evidence from human postmortem studies and transgenic MSA models suggests that oligodendroglial dysfunction both triggers and exacerbates neuronal degeneration. This review summarises the wide range of responsibilities of astroglia, microglia and oligodendroglia in the healthy brain and the changes in glial function associated with ageing. We then provide a critical analysis of the role of glia in α-synucleinopathies including putative mechanisms promoting a chronically diseased glial microenvironment which can lead to detrimental neuronal changes, including cell loss. Finally, major therapeutic strategies targeting glial pathology in α-synucleinopathies as well as current pitfalls for disease-modification in clinical trials are discussed.

Deep brain stimulation of the pedunculopontine nucleus in a patient with freezing of gait

CASE PRESENTATION

A 54-year-old male patient presenting probable multiple system atrophy with predominant parkinsonism who underwent bilateral deep brain stimulation (DBS) of the pedunculopontine nucleus (PPN) is presented. The patient had dominant freezing of gait (FOG), levodopa-resistant bradykinesia, and autonomic disturbances, but with a good cognitive condition.

METHODS

The patient underwent bilateral DBS of the PPN, which ended with modest benefits.

RESULTS AND CONCLUSION

Although he had a short postoperative follow-up (6 months), his neurological status remained stable and PPN DBS provided modest improvements in the gait disorder and freezing episodes. This unusual case suggests that the mesencephalic pedunculopontine region may have a role in locomotor symptoms and the potential to provide a limited improvement in FOG.

Cost-of-illness in multiple system atrophy and progressive supranuclear palsy

Multiple system atrophy and progressive supranuclear palsy are disabling neurodegenerative disorders, also known as atypical parkinsonian syndromes. Currently, no health economic evaluations of these diseases are available. The objective of this study was to evaluate disease-related costs in German patients with multiple system atrophy and progressive supranuclear palsy and to identify cost-driving factors. We recruited 101 consecutive patients with multiple system atrophy (n = 54) and progressive supranuclear palsy (n = 47) in four German specialised movement disorder clinics. The health economic data were collected using comprehensive health economic questionnaires ("bottom-up" approach). Costs were calculated from the societal perspective in 2010 Euros. Independent cost-driving factors were identified in multiple regression analysis. The total semi-annual costs of atypical parkinsonian syndromes were EUR 16,670 (95% CI: 13,470-21,850). Direct costs accounted for 73% (inpatient care 31%, special equipment 24%, copayments of patients 21%, others 24%) and indirect costs for 27% of total costs. The economic burden imposed on patients by atypical parkinsonian syndromes accounted for 36% of their income. Independent cost-driving factors were younger age, disease severity, living without a partner and depression. The disease-related costs of atypical parkinsonian syndromes in Germany are high and above the costs reported for idiopathic Parkinson's disease. Disease-specific patterns of cost distributions in atypical parkinsonian syndromes and independent cost-drivers should be considered in future health economic evaluations and healthcare programs. The early diagnosis and treatment of depression in patients with atypical parkinsonian syndromes as well as programs aimed to improve social support will reduce disease-related costs.

Survival of Korean patients with multiple system atrophy

METHODS

We conducted a retrospective medical record review to determine the survival of 455 Korean multiple system atrophy (MSA) patients and examined the effect of clinical factors that could possibly influence survival. The patients comprised 222 men and 233 women.

RESULTS

Age at onset was 60.1 ± 8.8 years (mean ± SD) and did not differ between the sexes. Parkinsonism was the most prevalent initial symptom, followed by cerebellar dysfunction and dysautonomia. Age at onset was significantly older in patients with predominant parkinsonism at the last visit (MSA-P) than in the other patients. At the time of data collection, 107 patients had died. Median survival time was 10 years. The survival rate of women was slightly better than that of men, especially in MSA-P patients.

CONCLUSIONS

Survival was not affected by age at onset, initial symptom, or predominant symptom at the last visit or by the presence of autonomic symptoms or multiple symptoms at disease onset.

In vivo comparison of Richardson's syndrome and progressive supranuclear palsy-parkinsonism

Richardson's syndrome (RS) and progressive supranuclear palsy-parkinsonism (PSP-P) are the most common subtypes of PSP. Post-mortem data suggests that the clinical presentation of the two subtypes differs especially in the first 2 years of disease and then converges. This hypothesis has, to our knowledge, never been confirmed in a living cohort. Medical history was used to define subtypes retrospectively in 23 consecutive PSP patients from our outpatient clinic specialized in movement disorders. 14 patients suffered from RS, and 9 from PSP-P. Using a prospective cross-sectional approach, clinical, cognitive, behavioral, speech and biochemical (cerebrospinal fluid tau levels) features were compared. RS patients showed shorter time from disease onset to diagnosis and more neuropsychological and neurobehavioral deficits than PSP-P patients, but differed not significantly with regard to clinical and biochemical features. RS and PSP-P show considerable symptoms overlap during the disease course when using routine assessments, with persisting differences regarding non-motor symptoms. Shorter disease duration of the comparably affected RS patients indicates that this subtype has an accelerated disease progression at early disease stages.

Hyposmia in progressive supranuclear palsy

Previous studies suggested that olfaction is normal in progressive supranuclear palsy (PSP). We applied the University of Pennsylvania Smell Identification Test (UPSIT) to 36 patients with PSP who scored more than 18 on the Mini Mental State Examination (MMSE), 140 patients with nondemented Parkinson's disease (PD) and 126 controls. Mean UPSIT scores in PSP were lower than in controls (P < 0.001) but higher than in PD (P < 0.001) after adjusting for age, gender, and smoking history. For patients with PSP, UPSIT scores correlated with MMSE (r = 0.44, P = 0.006) but not disease duration (P = 0.6), motor subscale of the Unified Parkinson's Disease Rating Scale (P = 0.2), or Frontal Assessment Battery (P = 0.5). The brains of six of the patients with PSP were examined postmortem and all revealed neurofibrillary tangles and tau accumulation in the rhinencephalon, although only three had hyposmia. Further prospective studies including patients with early PSP and PSP-P with postmortem confirmation might help clarify if smell tests could be useful when the differential diagnosis lies between PD and PSP.

The close relationship between life-threatening breathing disorders and urine storage dysfunction in multiple system atrophy

Survival of multiple system atrophy (MSA) depends on whether a variety of sleep-related breathing problems as well as autonomic failure (AF) occur. Since the brainstem lesions that cause respiratory and autonomic dysfunction overlap with each other, these critical manifestations might get worse in parallel. If so, the detection of AF, which is comparatively easy, might be predictive of a latent life-threatening breathing disorder. In 15 patients with MSA, we performed autonomic function tests composed of postural challenges and administered a questionnaire on bladder condition, as well as polysomnography and laryngoscopy during wakefulness and under anesthesia. Polysomnographic variables such as the apnea-hypopnea index (AHI) and oxygen saturation (SpO(2)) and the findings of laryngoscopy were compared with the degree of cardiac and urinary autonomic dysfunction. AHI, mean SpO(2) and the lowest SpO(2) showed significant correlations with urine storage dysfunction. In addition, patients with vocal cord abductor paralysis (VCAP) or central sleep apnea (CSA) contributing to nocturnal sudden death had more severe storage disorders than those without. On the other hand, no significant relationship between polysomnographic variables and orthostatic hypotension was observed except in the case of mean SpO(2). These results indicate that life-threatening breathing disorders have a close relationship with AF, and especially urine storage dysfunction. Therefore, longitudinal assessment of deterioration of the storage function might be useful for predicting the latent progress of VCAP and CSA.

FDG PET in the Evaluation of Parkinson's Disease

Network analysis of (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) is an innovative approach for the study of in movement disorders, such as Parkinson's disease (PD). Spatial covariance analysis of imaging data acquired from PD patients has revealed characteristic regional patterns associated with the motor and cognitive features of disease. Quantification of pattern expression in individual patients can be used for diagnosis, assessment of disease severity, and evaluation of novel medical and surgical therapies. Identification of disease-specific patterns in other parkinsonian syndromes, such as multiple system atrophy and progressive supranuclear palsy, has improved diagnostic accuracy in patients with difficult to diagnose parkinsonism. Further developments of these techniques are likely to enhance the role of functional imaging in investigating underlying abnormalities and potential new therapies in these neurodegenerative diseases.

Parkinson's disease

Parkinson's disease is a common progressive bradykinetic disorder that can be accurately diagnosed. It is characterised by the presence of severe pars-compacta nigral-cell loss, and accumulation of aggregated alpha-synuclein in specific brain stem, spinal cord, and cortical regions. The main known risk factor is age. Susceptibility genes including alpha-synuclein, leucine rich repeat kinase 2 (LRRK-2), and glucocerebrosidase (GBA) have shown that genetic predisposition is another important causal factor. Dopamine replacement therapy considerably reduces motor handicap, and effective treatment of associated depression, pain, constipation, and nocturnal difficulties can improve quality of life. Embryonic stem cells and gene therapy are promising research therapeutic approaches.

Recent developments in multiple system atrophy

Multiple system atrophy (MSA) is a rare late onset neurodegenerative disorder which presents with autonomic failure and a complicated motor syndrome including atypical parkinsonism, ataxia and pyramidal signs. MSA is a glial alpha-synucleinopathy with rapid progression and currently poor therapeutic management. This paper reviews the clinical features, natural history and novel diagnostic criteria for MSA as well as contemporary knowledge on pathogenesis based on evidence from neuropathological studies and experimental models. An outline of the rationale for managing symptomatic deterioration in MSA is provided together with a summary of novel experimental therapeutic approaches to decrease disease progression.

Depletion of medullary serotonergic neurons in patients with multiple system atrophy who succumbed to sudden death

Multiple system atrophy (MSA) is a neurodegenerative disorder characterized by prominent autonomic failure with ataxia and/or parkinsonism. The leading cause of death in MSA is sudden death. We have shown that the early development of autonomic failure is an independent risk factor for sudden death. The depletion of sympathetic preganglionic neurons in the spinal intermediolateral cell column (IML) and its afferent medullary catecholaminergic and serotonergic neurons has been proposed to be partly responsible for autonomic failure in MSA. In this study, we investigated whether the depletion of neurons in any of these autonomic neuron groups contributes to sudden death in MSA. Out of 52 autopsy-proven patients with MSA, we selected 12 individuals who had died within 3.5 years after disease onset to define the accurate levels of slices and identify early neuropathological changes of autonomic nuclei in MSA. Four patients succumbed to sudden death and eight patients died through established causes. Serial 10 mum sections were obtained from the 8th segment of the thoracic cord and the rostral medulla oblongata. Sections from the medulla oblongata were immunostained for thyrosine hydroxylase and tryptophan hydroxylase. The total cell number in the five sections was computed for comparison. Compared with the control, the MSA group showed a marked depletion of neurons in the IML (38.0 +/- 7.1 versus 75.2 +/- 7.6 cells, P < 0.001), thyrosine hydroxylase-immunoreactive neurons in the ventrolateral medulla (VLM) (17.4 +/- 5.1 versus 72.8 +/- 13.6 cells, P < 0.01) and tryptophan hydroxylase-immunoreactive neurons in the VLM (15.6 +/- 9.2 versus 60.8 +/- 17.0 cells, P < 0.01), nucleus raphe obscurus (19.3 +/- 4.4 versus 75.3 +/- 8.6 cells, P < 0.001), nucleus raphe pallidus (2.1 +/- 2.7 versus 9.0 +/- 3.4 cells, P < 0.03), and arcuate nucleus (0.4 +/- 0.8 versus 2.3 +/- 1.5 cells, P < 0.05). Moreover, in patients who succumbed to sudden death, when compared with patients who had established causes of death, we found a marked depletion of tryptophan hydroxylase-immunoreactive neurons in the VLM (7.3 +/- 3.5 versus 21.8 +/- 6.5 cells, P < 0.02) and nucleus raphe obscurus (15.0 +/- 2.0 versus 22.5 +/- 2.1 cells, P < 0.01). The results indicate that the spinal IML and medullary catecholaminergic and serotonergic systems are involved even in the early stages of MSA, and the dysfunction of the medullary serotonergic system regulating cardiovascular and respiratory systems could be responsible for sudden death in patients with MSA.

Progressive supranuclear palsy: clinicopathological concepts and diagnostic challenges

Progressive supranuclear palsy (PSP) is a clinical syndrome comprising supranuclear palsy, postural instability, and mild dementia. Neuropathologically, PSP is defined by the accumulation of neurofibrillary tangles. Since the first description of PSP in 1963, several distinct clinical syndromes have been described that are associated with PSP; this discovery challenges the traditional clinicopathological definition and complicates diagnosis in the absence of a reliable, disease-specific biomarker. We review the emerging nosology in this field and contrast the clinical and pathological characteristics of the different disease subgroups. These new insights emphasise that the pathological events and processes that lead to the accumulation of phosphorylated tau protein in the brain are best considered as dynamic processes that can develop at different rates, leading to different clinical phenomena. Moreover, for patients for whom the diagnosis is unclear, clinicians must continue to describe accurately the clinical picture of each individual, rather than label them with inaccurate diagnostic categories, such as atypical parkinsonism or PSP mimics. In this way, the development of the clinical features can be informative in assigning less common nosological categories that give clues to the underlying pathology and an understanding of the expected clinical course.