The prevalence of progressive supranuclear palsy (Steele-Richardson-Olszewski syndrome) in the UK

Pharmacotherapies for the Treatment of Progressive Supranuclear Palsy: A Narrative Review

Progressive supranuclear palsy (PSP) is a neurodegenerative disorder resulting from the deposition of misfolded and neurotoxic forms of tau protein in specific areas of the midbrain, basal ganglia, and cortex. It is one of the most representative forms of tauopathy. PSP presents in several different phenotypic variations and is often accompanied by the development of concurrent neurodegenerative disorders. PSP is universally fatal, and effective disease-modifying therapies for PSP have not yet been identified. Several tau-targeting treatment modalities, including vaccines, monoclonal antibodies, and microtubule-stabilizing agents, have been investigated and have had no efficacy. The need to treat PSP and other tauopathies is critical, and many clinical trials investigating tau-targeted treatments are underway. In this review, the PubMed database was queried to collect information about preclinical and clinical research on PSP treatment. Additionally, the US National Library of Medicine's ClinicalTrials.gov website was queried to identify past and ongoing clinical trials relevant to PSP treatment. This narrative review summarizes our findings regarding these reports, which include potential disease-modifying drug trials, modifiable risk factor management, and symptom treatments.

Impaired sequence manipulation in non-demented patients with progressive supranuclear palsy

PURPOSE

Sequential working memory is the ability to maintain and manipulate sequential information at a second time scale. Patients with progressive supranuclear palsy (PSP) or Parkinson's disease (PD) perform poorly in tests that require the flexible arrangement of thoughts or actions. This study investigated whether sequential working memory is differently impaired in patients with PSP versus PD.

METHOD

Twenty-nine patients with PSP Richardson's syndrome (PSP-RS), 36 patients with PD, and 36 healthy controls (HC) completed 3 well-established neuropsychological tests, including digit span forward (DST-F), digit span backward (DST-B), and adaptive digit ordering tests (DOT-A). The DST-F required maintaining digit sequences, and the DST-B and DOT-A required maintaining and manipulating digit sequences.

FINDING

The PSP-RS group scored lower than the PD and HC groups in the DST-B and DOT-A but not in the DST-F, indicating that the ability to manipulate sequences was impaired, but the maintenance ability was preserved in PSP-RS patients. Moreover, in PSP-RS, the DST-B score negatively correlated with the severity of motor symptoms. The actual levodopa dose positively correlated with the DST-B ordering cost (DST-F score vs. DST-B score). The PSP patients who took a greater dose of levodopa tended to have higher DST-B ordering cost. There was no effect of levodopa on DST-B or DOT-A in PD.

CONCLUSION

These results suggested that the ability to manipulate sequence was already reduced in patients with PSP-RS and was worse than in patients with PD.

Dysphagia Prevalence in Progressive Supranuclear Palsy: A Systematic Review and Meta-Analysis

The objective of this systematic review was to determine the prevalence of dysphagia and aspiration in people with progressive supranuclear palsy (PSP). A search of six electronic databases was performed from inception to April 2022. No context restrictions were set. All primary research comprising figures to derive a prevalence rate were included. Two independent reviewers screened search results. Data were extracted by one reviewer. Conflicts were resolved by discussion with a third reviewer. The quality of included studies was assessed using the JBI Checklist for Prevalence Studies. From 877 studies, 12 were eligible for inclusion. Dysphagia had to be confirmed using instrumental assessments, clinical swallowing evaluation, screening, and patient-reported outcome measures (PROM). A random-effects meta-analysis calculated a pooled dysphagia prevalence in 78-89% (95% CI [60.6, 89.1], [78.9, 95.0]). depending on the chosen assessment method, and a pooled aspiration prevalence of 23.5% (95% CI [14.5, 33.7]). The included studies were of moderate quality, with high risk of selection and coverage bias and low to moderate risk of measurement bias. Dysphagia is highly prevalent in a sample of participants with mostly moderately severe PSP. Aspiration occurs in a quarter of this sample and is likely to increase as the disease progresses. Given the low general prevalence of PSP, studies remain at high risk for selection bias. Prospective research should focus on the development of dysphagia in the course of PSP and its subcategories using instrumental assessment and consider all phases of swallowing. REGISTRATION: The protocol of this systematic review was registered on the International Prospective Register of Systematic Reviews (PROSPERO) in April 2021 (registration number: CRD42021245204).

The prevalence and incidence of progressive supranuclear palsy and corticobasal syndrome: a systematic review and meta-analysis

INTRODUCTION

Progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS) are progressive neurodegenerative syndromes characterised by Parkinsonism with additional features including cognitive dysfunction, falls, and oculomotor abnormalities. Understanding the epidemiology of these conditions is critical to planning for future service provision.

METHODS

We conducted a systematic review of studies reporting incidence and prevalence of CBS and PSP. A search of the PubMed and EMBASE data bases was conducted from their date of inception to 13th July 2021. Meta-analysis of studies sharing similar methodologies was carried out to generate estimated pooled prevalence and incidence.

RESULTS

We found 32 studies meeting our criteria for inclusion. There were 20 studies with data on prevalence and 12 with incidence data of PSP. Prevalence of CBS was reported in eight studies while seven studies reported incidence. Reported estimates of prevalence for PSP ranged from 1.00 (0.9-1.1) to 18 (8-28) per 100,000 while prevalence rates for CBS ranged from 0.83 (0.1-3.0) to 25 (0-59). Incidence rates for PSP and CBS respectively ranged from 0.16 (0.07-0.39) to 2.6 per 100,000 person-years and 0.03 (0-0.18) to 0.8 (0.4-1.3) per 100,000 person-years. A random effects model meta-analysis of studies with similar methodologies yielded a pooled prevalence estimate for PSP of 6.92 (4.33-11.06, I2 = 89%, τ2 = 0.3907) and 3.91 (2.03-7.51, I2 = 72%, τ2 = 0.2573) per 100,000 for CBS.

CONCLUSION

Studies of the epidemiology of PSP and CBS report highly heterogeneous findings. There is a need for further studies using rigorous phenotyping and the most recent diagnostic criteria to understand the true burden of these conditions.

Progression of atypical parkinsonian syndromes: PROSPECT-M-UK study implications for clinical trials

The advent of clinical trials of disease-modifying agents for neurodegenerative disease highlights the need for evidence-based end point selection. Here we report the longitudinal PROSPECT-M-UK study of progressive supranuclear palsy (PSP), corticobasal syndrome (CBS), multiple system atrophy (MSA) and related disorders, to compare candidate clinical trial end points. In this multicentre UK study, participants were assessed with serial questionnaires, motor examination, neuropsychiatric and MRI assessments at baseline, 6 and 12 months. Participants were classified by diagnosis at baseline and study end, into Richardson syndrome, PSP-subcortical (PSP-parkinsonism and progressive gait freezing subtypes), PSP-cortical (PSP-frontal, PSP-speech and language and PSP-CBS subtypes), MSA-parkinsonism, MSA-cerebellar, CBS with and without evidence of Alzheimer's disease pathology and indeterminate syndromes. We calculated annual rate of change, with linear mixed modelling and sample sizes for clinical trials of disease-modifying agents, according to group and assessment type. Two hundred forty-three people were recruited [117 PSP, 68 CBS, 42 MSA and 16 indeterminate; 138 (56.8%) male; age at recruitment 68.7 ± 8.61 years]. One hundred and fifty-nine completed the 6-month assessment (82 PSP, 27 CBS, 40 MSA and 10 indeterminate) and 153 completed the 12-month assessment (80 PSP, 29 CBS, 35 MSA and nine indeterminate). Questionnaire, motor examination, neuropsychiatric and neuroimaging measures declined in all groups, with differences in longitudinal change between groups. Neuroimaging metrics would enable lower sample sizes to achieve equivalent power for clinical trials than cognitive and functional measures, often achieving N < 100 required for 1-year two-arm trials (with 80% power to detect 50% slowing). However, optimal outcome measures were disease-specific. In conclusion, phenotypic variance within PSP, CBS and MSA is a major challenge to clinical trial design. Our findings provide an evidence base for selection of clinical trial end points, from potential functional, cognitive, clinical or neuroimaging measures of disease progression.

Differences Among Native Hawaiian, Asian, and White Patients with Progressive Supranuclear Palsy

BACKGROUND

Most studies of progressive supranuclear palsy (PSP) have been conducted in White populations.

OBJECTIVE

The objective of this study was to identify whether differences exist for patients with PSP among Whites, East Asians (EAs), and Native Hawaiians/Pacific Islanders (NHPIs) in Hawaii.

METHODS

We conducted a single-center, retrospective study of patients meeting Movement Disorder Society probable PSP criteria (2006-2021). Data variables included age of onset and diagnosis, comorbidities, and survival rate. Variables were compared across groups using Fisher's exact test, Kruskal-Wallis rank sum test, and log-rank tests.

RESULTS

A total of 94 (59 EAs, 9 NHPIs, 16 Whites, and 10 Others) patients were identified. Mean age ± standard deviation (in years) of symptom onset/diagnosis were both youngest in NHPIs (64.0 ± 7.2/66.3 ± 8.0) followed by Whites (70.8 ± 7.6/73.9 ± 7.8), then EAs (75.9 ± 8.2/79.2 ± 8.3) (P < 0.001). Median survival from diagnosis was significantly lower (P < 0.05) in NHPIs (2 years) compared with EAs (4 years) and Whites (6 years).

CONCLUSIONS

There may be racial disparities for PSP, and studies are needed to identify genetic, environmental, and socioeconomic contributions. © 2023 International Parkinson and Movement Disorder Society.

Low clinical sensitivity and unexpectedly high incidence for neuropathologically diagnosed progressive supranuclear palsy

The objective of this study was to determine the prevalence, incidence, and clinical diagnostic accuracy for neuropathologically diagnosed progressive supranuclear palsy (PSP) with data from a longitudinal clinicopathological study using Rainwater criteria to define neuropathological PSP. Of 954 autopsy cases, 101 met Rainwater criteria for the neuropathologic diagnosis of PSP. Of these, 87 were termed clinicopathological PSP as they also had either dementia or parkinsonism or both. The prevalence of clinicopathologically defined PSP subjects in the entire autopsy dataset was 9.1%, while the incidence rate was estimated at 780 per 100 000 persons per year, roughly 50-fold greater than most previous clinically determined PSP incidence estimates. A clinical diagnosis of PSP was 99.6% specific but only 9.2% sensitive based on first examination, and 99.3% specific and 20.7% sensitive based on the final clinical exam. Of the clinicopathologically defined PSP cases, 35/87 (∼40%) had no form of parkinsonism at first assessment, while this decreased to 18/83 (21.7%) at final assessment. Our study confirms a high specificity but low sensitivity for the clinical diagnosis of PSP. The low clinical sensitivity for PSP is likely primarily responsible for previous underestimates of the PSP population incidence rate.

Neurological update: the palliative care landscape for atypical parkinsonian syndromes

Atypical parkinsonian syndromes are neurodegenerative conditions, characterised by rapid disease progression and shorter life expectancy compared to idiopathic Parkinson's disease. These conditions inflict substantial physical and psychosocial burden on patients and their families; hence, there is a clear rationale for a palliative care approach from diagnosis. An interdisciplinary care model has been shown to improve symptom burden, quality of life and engagement with advance care planning, in a heterogeneous group of neurodegenerative conditions. In this update, we summarise how the landscape for treating these patients has changed and the questions that still need to be resolved.

microRNA and circRNA in Parkinson's Disease and atypical parkinsonian syndromes

Multiple System Atrophy (MSA) and Progressive Supranuclear Palsy (PSP) are atypical parkinsonian syndromes (APS) with various clinical phenotypes and considerable clinical overlap with idiopathic Parkinson's disease (iPD). This disease heterogeneity makes ante-mortem diagnosis extremely challenging with up to 24% of patients misdiagnosed. Because diagnosis is predominantly clinical, there is great interest in identifying biomarkers for early diagnosis and differentiation of the different types of parkinsonism. Compared to protein biomarkers, microRNAs (miRNAs) and circularRNAs (circRNAs) are stable tissue-specific molecules that can be accurately measured by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). This chapter critically reviews miRNAs and circRNAs as diagnostic biomarkers and therapeutics to differentiate atypical parkinsonian disorders and their role in disease pathogenesis.

Global Epidemiology of Movement Disorders: Rare or Underdiagnosed?

In this manuscript, we review the epidemiology of movement disorders including Parkinson's disease (PD), atypical parkinsonism, essential tremor, dystonia, functional movement disorders, tic disorders, chorea, and ataxias. We emphasize age-, sex-, and geography-based incidence and prevalence, as well as notable trends including the rising incidence and prevalence of PD. Given the growing global interest in refining clinical diagnostic skills in recognizing movement disorders, we highlight some key epidemiological findings that may be of interest to clinicians and health systems tasked with diagnosing and managing the health of patients with movement disorders.

Epidemiology of Progressive Supranuclear Palsy: Real World Data from the Second Largest Health Plan in Israel

Progressive supranuclear palsy (PSP) is a rare and fatal neurodegenerative movement disorder and no disease modifying therapy (DMT) is currently available. This study aims to assess the epidemiology of PSP in Israel and to describe its clinical features. This retrospective analysis identified patients with PSP between 2000 and 2018 over the age of 40 years at first diagnosis (index date). We identified 209 patients with ≥1 diagnosis of PSP. Of those, 88 patients satisfied the inclusion criteria with a mean age at diagnosis of 72 years (SD = 8) and 53% were female. The 2018 prevalence and incidence rates were 5.3 and 1 per 100,000 persons, respectively. Median survival time was 4.9 years (95% CI 3.6–6.1) and median time from initial symptom to diagnosis was 4.2 years. The most common misdiagnoses were Parkinson’s disease, cognitive disorder and depression. The present study demonstrates that the clinic-epidemiological features of PSP in Israel are similar to PSP worldwide. In light of PSP’s rarity, investigation of PSP cohorts in different countries may create a proper platform for upcoming DMT trials.

Striatal dopaminergic lesions contributed to the disease severity in progressive supranuclear palsy

Background

Reduced dopamine transporter (DAT) binding in the striatum has been reported in patients with progressive supranuclear palsy (PSP). However, the relationship between striatal dopaminergic lesions and the disease severity of PSP remains to be explored.

Objective

To investigate the contributions of striatal dopaminergic lesions to the disease severity of PSP.

Methods

One hundred patients with clinically diagnosed PSP were consecutively enrolled in this study. The disease severity was systemically assessed using the PSP rating scale (PSPrs), and the dopaminergic lesions were assessed using the 11C-N-2-carbomethoxy-3-(4-fluorophenyl)-tropane positron emission tomography (11C-CFT PET) imaging. To explore the correlations between striatal DAT bindings and the disease severity, both the region-wise and voxel-wise analysis were adopted. Partial correlations and multiple linear regressions were performed to investigate the contribution of striatal dopaminergic lesions to the disease severity in PSP.

Results

Sixty-three patients of PSP with Richardson’s syndrome (PSP-RS) and 37 patients with PSP-non-RS were finally included. The disease severity in PSP-RS was much heavier than that in the PSP-non-RS. The DAT bindings in the caudate and anterior putamen correlated significantly with the PSPrs total scores, mainly in the domains of history, mentation, bulbar, and ocular motor symptoms. The striatal DAT bindings (caudate) contributed significantly to the disease severity of PSP, independent of the motor, cognition, emotion and behavioral dysfunctions.

Conclusion

Our study highlighted the independent contribution of striatal dopaminergic lesions to the disease severity in PSP.

The emerging role of LRRK2 in tauopathies

Parkinson's disease (PD) is conventionally described as an α-synuclein aggregation disorder, defined by Lewy bodies and neurites, and mutations in leucine-rich repeat kinase 2 (LRRK2) are the most common autosomal dominant cause of PD. However, LRRK2 mutations may be associated with diverse pathologies in patients with Parkinson's syndrome including tau pathology resembling progressive supranuclear palsy (PSP). The recent discovery that variation at the LRRK2 locus is associated with the progression of PSP highlights the potential importance of LRRK2 in tauopathies. Here, we review the emerging evidence and discuss the potential impact of LRRK2 dysfunction on tau aggregation, lysosomal function, and endocytosis and exocytosis.

The prevalence of progressive supranuclear palsy and corticobasal syndrome in Scotland

Introduction We estimated the point prevalence of progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS) at regional and national levels in Scotland, UK as there are few high-quality prevalence studies of these conditions. Methods Nationally, multiple methods of case ascertainment were used including clinician and nurse specialist referral, searches of ICD-10 diagnostic coding in routinely collected electronic health data (Scottish Morbidity Record), and patient self-referral. In one region we also searched GP databases and unselected hospital correspondence. Cases were verified by clinical examination or medical record review. National and regional total and age-sex stratified crude prevalence rates on 31st December 2018 were calculated. Results The regional crude point prevalence was 4.28 per 100,000 (95% CI 2.90, 6.31) for PSP, and 2.05 per 100,000 (95% CI 1.17, 3.59) for CBS. The national crude prevalence rates were lower due to the greater reliance on passive case ascertainment. There were no clear sex differences. At a national level, the peak crude prevalence rate for both PSP and CBS was in the 70-79 age-group. Discussion The prevalence rates of PSP and CBS were similar to previous estimates with little change over the past 20 years.

Probable progressive supranuclear palsy in a patient with chronic schizophrenia: A case report

Rare neurodegenerative disorders may be considered in the differential diagnosis of Parkinsonism in patients with schizophrenia who show worsening signs of Parkinsonism under treatment with antipsychotics. To the best of our knowledge, the present study is the first report describing probable progressive supranuclear palsy (PSP) in a patient with chronic schizophrenia. A 64-year-old man presented with hallucinations, delusions and asociality. He had received treatment with both typical and atypical antipsychotics for ~13 years. He began experiencing short-term memory impairment and bradykinesia two years before presentation, and then showed increased dysphagia, upper-limb muscle rigidity, extrapyramidal symptoms, vision loss and photophobia. Psychological manifestations included chronic depression, irritability and, occasionally, euphoria. His gait worsened, leading to repeated falls. Antipsychotics were discontinued, and the patient was almost completely dependent on a wheelchair in daily life. In a neurology consultation, he was diagnosed with probable progressive supranuclear palsy-Richardson's syndrome presenting as vertical supranuclear gaze palsy and prominent postural instability with falls. Brain magnetic resonance imaging (MRI) revealed atrophy of the mesencephalic tegmentum, and ¹²³I-ioflupane single-photon emission computed tomography (SPECT) revealed reduced bilateral striatal reuptake. Overall, PSP should be considered in patients with schizophrenia with worsening Parkinsonism, especially when it is accompanied by supranuclear ophthalmoplegia, pseudobulbar palsy, dysarthria and dystonic stiffness of the neck and upper body. In the present case, the combination of brain MRI and ¹²³I-ioflupane SPECT helped to discriminate PSP from other Parkinsonian syndromes, including drug-induced Parkinsonism, in the differential diagnosis.

Depression and Apathy across Different Variants of Progressive Supranuclear Palsy

BACKGROUND

Apathy and depression commonly occur in patients with progressive supranuclear palsy (PSP)-Richardson's syndrome variant; depression often requiring treatment. Little is known, however, about apathy and depression among other PSP variants.

METHODS

We prospectively studied 97 newly diagnosed PSP patients. All were classified into a PSP variant using the 2017 Movement Disorder Society-PSP criteria and administered the Geriatric Depression and Apathy Evaluation Scales. Differences in apathy and depression frequency and severity across six variants, and secondarily across PSP-Richardson's syndrome, PSP-Cortical and PSP-Subcortical, were analyzed using ANCOVA and linear regression adjusting for disease severity.

RESULTS

Depression (55%) was more common than apathy (12%). PSP-Speech/Language (PSP-SL) variant had the lowest depression frequency (13%) and lower depression scores than the other variants. No differences in apathy frequency/severity were identified.

CONCLUSION

PSP-SL patients may have less depression compared to PSP-Richardson's syndrome and other PSP variants.

[Progressive supranuclear palsy]

Progressive supranuclear palsy (PSP) is a heterogeneous progressive neurodegenerative disease characterized by onset after 50 years old, Parkinson's syndrome, early development of postural instability, absence or transient reaction to levodopa drugs, neuropsychological disorders, dysphagia and dysarthria and eye movement disorders. The review provides an analysis of modern data on etiology, clinical presentation, differential diagnosis of the disease. The morphological picture and neuroimaging features, as well as modern ideas about treatment, are described. A great clinical polymorphism of the disease, as well as its similarity to other neurodegenerative diseases, manifested by Parkinson's syndrome, complicates the diagnosis of PSP. Establishing an accurate diagnosis makes it possible to determine the prognosis and further tactics of patient management.

Clinical Features of Patients With Progressive Supranuclear Palsy in an US Insurance Claims Database

Background: Progressive supranuclear palsy is a rare neurodegenerative movement disorder and little is known about its epidemiology.

Objective: Estimate age-adjusted prevalence of progressive supranuclear palsy and describe antecedent diagnoses and progressive supranuclear palsy patient features in the 5 years before first diagnostic code.

Methods: In a nested case-control study in the IBM MarketScan Commercial and Medicare Supplemental Databases, a large set of US insurance databases containing medical service and prescription drug claims from employer-based commercial and Medicare supplemental health insurance plans, progressive supranuclear palsy cases (identified via International Statistical Classification of Diseases 9th/10th revision codes) and controls were included if enrollment was ≥1 month in the study period (October 1, 2015–October 31, 2017). Two controls with no diagnosis codes for PSP were matched to cases on birth year, sex, enrollment time in the database, and pharmacy benefit eligibility. Controls were assigned a randomly selected index date from their eligibility period. Prevalence of progressive supranuclear palsy was estimated in 2016 among patients with ≥1 month of continuous enrollment in that year. Prevalence ratios for comorbidities (claim/diagnosis codes) were examined in the ≤ 5 years before index date (first progressive supranuclear palsy claim date).

Results: Age-adjusted progressive supranuclear palsy prevalence was 2.95/100,000 in 2016. The most common diagnosis codes in cases vs. controls in the 5 years pre-index were gait abnormalities (79.3 vs. 21.8%), pain in joint (54.9 vs. 36.0%), Parkinson's disease (54.6 vs. 1.0%), fatigue (49.8 vs. 21.6%), and cerebrovascular disease (45.6 vs. 16.4%).

Conclusions: In this large database analysis, based on preliminary analyses, the prevalence of diagnosed progressive supranuclear palsy was 2.95/100,000, which is lower than many prior studies. Typical symptoms suggestive of progressive supranuclear palsy were present before index date, indicating a potential delay in time to diagnosis. The identification of diagnostic codes for clinical features of progressive supranuclear palsy that occurred before index date may be used to develop predictive models to identify potential progressive supranuclear palsy patients earlier in their disease course.

Environmental Risk Factors for Progressive Supranuclear Palsy

Typically, progressive supranuclear palsy (PSP) is clinically characterized by slow vertical saccades or supranuclear gaze palsy, levodopa-resistant parkinsonism with predominant axial symptoms, and cognitive executive impairment. Over the past decades, various PSP phenotypes, including PSP with predominant parkinsonism, PSP with corticobasal syndrome, PSP with progressive gait freezing, and PSP with predominant frontal dysfunction, have been identified from pathologically confirmed cases. Expanding knowledge led to new diagnostic criteria for PSP that with increased disease awareness led to increased PSP prevalence estimates. The identification of environmental and modifiable risk factors creates an opportunity to intervene and delay the onset of PSP or slow disease progression. To date, despite the increasing number of publications assessing risk factors for PSP, few articles have focused on environmental and lifestyle risk factors for this disorder. In this article, we reviewed the literature investigating the relationship between PSP and several environmental and other modifiable lifestyle risk factors. In our review, we found that exposures to toxins related to diet, metals, well water, and hypertension were associated with increased PSP risk. In contrast, higher education and statins may be protective. Further case-control studies are encouraged to determine the exact role of these factors in the etiopathogenesis of PSP, which in turn would inform strategies to prevent and reduce the burden of PSP.

Gene-Environment Interactions in Progressive Supranuclear Palsy

Several genetic and environmental factors have been reported in progressive supranuclear palsy (PSP), although none were identified as a definitive cause. We aimed to explore potential gene-environment interactions in PSP. Two hundred and ninety two PSP cases and 292 controls matched for age, sex, and race from the ENGENE-PSP were analyzed to determine the association between PSP and minor alleles of 5 single nucleotide polymorphisms (SNPs) in 4 genes (MAPT, MOBP, EIF2AK3, and STX6), which were previously associated with PSP risk. Interactions between these SNPs and environmental factors, including previously reported occupational and agricultural risk factors for PSP, were assessed for PSP odds and age of symptom onset. Minor alleles of MAPTrs242557 and EIF2AK3rs7571971 were individually associated with increased odds; MAPTrs8070723 minor alleles were associated with lower PSP odds. There were several gene-environment interactions for PSP odds and age of symptom onset, however, they did not remain significant after FDR-correction. Larger scale studies are required to determine potential interactions.

Association of Progressive Supranuclear Palsy Rating Scale with Progressive Supranuclear Palsy Quality of Life Scale

INTRODUCTION

There is growing interest in using patient-reported outcomes as end points in clinical trials, such as the progressive supranuclear palsy quality of life (PSP-QoL) scale. However, this tool has not been widely validated and its correlation with validated motor scales has not been explored. To evaluate the potential utility of using PSP-QoL as an outcome, it is important to examine its relationship with a standard scale used to evaluate neurologic parameters, such as the PSP Rating Scale.

METHODS

PSP-QoL and PSP Rating Scale scores were gathered from 60 clinically diagnosed PSP patients, including patients with Richardson syndrome PSP (PSP-RS, n = 43) and those with non-RS PSP variants (n = 17). Linear regression analysis adjusted for age, sex, and disease duration was used to evaluate the cross-sectional relationship between the total and subscale scores of the 2 instruments.

RESULTS

Among 60 PSP patients, there was a significant correlation between total PSP-QoL and PSP Rating Scale scores. The physical and mentation subscales of each instrument also demonstrated significant correlations. Comparisons among PSP subtypes indicated that worsening PSP-QoL Total and Physical subscale scores correlated with worsening PSP Rating Scale gait subscale scores more strongly for the non-RS PSP variants than for PSP-RS.

DISCUSSION

There is a significant association between the total scores and many of the subscale scores of the PSP-QoL and the PSP Rating Scale. Additionally, the relationship between these measures may differ for PSP-RS and non-RS variants. These findings suggest that the PSP-QoL may be useful in clinical trials as a patient-reported outcome measure. Large prospective multicenter studies utilizing the PSP-QoL are necessary to examine its relationship to disease evolution and changes in the PSP Rating Scale.

Quantitative evaluation of oculomotor disturbances in progressive supranuclear palsy

OBJECTIVES

To explore and quantify systematically the ocular abnormal movements present in progressive supranuclear palsy (PSP) from the early stages, to assess the ability of this standardized examination in the differential diagnosis of PSP from Parkinson's disease (PD), and to compare in more detail oculomotor disturbances between PSP variants.

METHODS

Sixty-five consecutive PSP patients with <5 years of disease duration diagnosed according to MDS-PSP criteria, 25 PD patients and 25 controls comparable in age, education and disease duration were explored using a bedside battery of tests for the quantitative evaluation of oculomotor dysfunction in clinical practice. Other accepted scales were used for measurement of motor (PSPRS), cognitive (FAB) and behavioral (FBI) impairment.

RESULTS

Measurement of oculomotor dysfunction significantly differentiated PSP from PD and controls (p < 0.001) and showed high accuracy in the differential diagnosis of early-to-mid stage PSP from PD. PSP-Parkinsonism and PSP-Progressive Gait Freezing phenotypes showed more preserved ocular motor function compared to PSP-Richardson Syndrome, although no differences were found between PSP subtypes in the number of square wave jerks, optokinetic nystagmus defects, degree of apraxia of eyelid opening, or presence of the "Round the Houses" sign.

CONCLUSIONS

Using a bedside clinical instrument for quantifying oculomotor disturbances in PSP shows promising potential at differentiating PSP from PD, and it seems able to provide a qualitative and quantitative description of ocular motor function in parkinsonian disorders.

Cognitive and behavioral profile of progressive supranuclear palsy and its phenotypes

BACKGROUND

Although several progressive supranuclear palsy (PSP) phenotypes have recently been described, studies identifying cognitive and neuropsychiatric differences between them are lacking.

METHODS

An extensive battery of cognitive and behavioural assessments was administered to 63 PSP patients, 25 PD patients with similar sociodemographic characteristics, and 25 healthy controls. We analysed differences in phenomenology, frequency and severity of cognitive and neuropsychiatric symptoms between PSP, PD and HC, and between PSP subtypes.

RESULTS

Regarding phenotypes, 64.6% met criteria for Richardson's syndrome (PSP-RS), 10.7% PSP with predominant Parkinsonism (PSP-P), 10.7% with PSP progressive gait freezing (PSP-PGF), and 10.7% PSP with predominant speech/language disorder (PSP-SL). Impairment was more severe in the PSP group than in the PD and HC groups regarding motor scores, cognitive testing and neuropsychiatric scales. Cognitive testing did not clearly differentiate between PSP phenotypes, but PSP-RS and PSP-SL appeared to have more cognitive impairment than PSP-PGF and PSP-P, mainly due to an increased impairment in frontal executive domains. Regarding neuropsychiatric disturbances, no specific behavior was more common in any of the PSP subtypes.

CONCLUSION

Motor deficits delineate the phenotypes included in currently accepted MDS-PSP criteria. Cognition and behavioural disturbances are common in PSP and allow us to distinguish this disorder from other neurological diseases, but they do not differentiate between PSP phenotypes.

Spatial attention and spatial short term memory in PSP and Parkinson's disease

Progressive Supranuclear Palsy (PSP) is a neurodegenerative disorder characterised by deterioration in motor, oculomotor and cognitive function. A key clinical feature of PSP is the progressive paralysis of eye movements, most notably for vertical saccades. These oculomotor signs can be subtle, however, and PSP is often misdiagnosed as Parkinson's disease (PD), in its early stages. Although some of the clinical features of PD and PSP overlap, they are distinct disorders with differing underlying pathological processes, responses to treatment and prognoses. One key difference lies in the effects the diseases have on cognition. The oculomotor system is tightly linked to cognitive processes such as spatial attention and spatial short-term memory (sSTM), and previous studies have suggested that PSP and PD experience different deficits in these domains. We therefore hypothesised that people with PSP (N = 15) would experience problems with attention (assessed with feature and conjunction visual search tasks) and sSTM (assessed with the Corsi blocks task) compared to people with PD (N = 16) and Age Matched Controls (N = 15). As predicted, feature and conjunction search were sgnificantly slower in the PSP group compared to the other groups, and this deficit was significantly worse for feature compared to conjunction search. The PD group did not differ from AMC on feature search but were significantly impaired on the conjunction search. The PSP group also had a pronounced vertical sSTM impairment that was not present in PD or AMC groups. It is argued that PSP is associated with specific impairment of visuospatial cognition which is caused by degeneration of the oculomotor structures that support exogenous spatial attention, consistent with oculomotor theories of spatial attention and memory.

Molecular Processing of Tau Protein in Progressive Supranuclear Palsy: Neuronal and Glial Degeneration

BACKGROUND

Alzheimer's disease (AD) and progressive supranuclear palsy (PSP) are examples of neurodegenerative diseases, characterized by abnormal tau inclusions, that are called tauopathies. AD is characterized by highly insoluble paired helical filaments (PHFs) composed of tau with abnormal post-translational modifications. PSP is a neurodegenerative disease with pathological and clinical heterogeneity. There are six tau isoforms expressed in the adult human brain, with repeated microtubule-binding domains of three (3R) or four (4R) repeats. In AD, the 4R:3R ratio is 1:1. In PSP, the 4R isoform predominates. The lesions in PSP brains contain phosphorylated tau aggregates in both neurons and glial cells.

OBJECTIVE

Our objective was to evaluate and compare the processing of pathological tau in PSP and AD.

METHODS

Double and triple immunofluorescent labeling with antibodies to specific post-translational tau modifications (phosphorylation, truncation, and conformational changes) and thiazin red (TR) staining were carried out and analyzed by confocal microscopy.

RESULTS

Our results showed that PSP was characterized by phosphorylated tau in neurofibrillary tangles (NFTs) and glial cells. Tau truncated at either Glu391 or Asp421 was not observed. Extracellular NFTs (eNFTs) and glial cells in PSP exhibited a strong affinity for TR in the absence of intact or phosphorylated tau.

CONCLUSION

Phosphorylated tau was as abundant in PSP as in AD. The development of eNFTs from both glial cells and neuronal bodies suggests that truncated tau species, different from those observed in AD, could be present in PSP. Additional studies on truncated tau within PSP lesions could improve our understanding of the pathological processing of tau and help identify a discriminatory biomarker for AD and PSP.

Progressive Supranuclear Palsy and Corticobasal Degeneration

Progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD) are neurodegenerative tauopathies with neuronal and glial lesions composed of tau that is composed predominantly of isomers with four repeats in the microtubule-binding domain (4R tau). The brain regions vulnerable to pathology in PSP and CBD overlap, but there are differences, particularly with respect to distribution of neuronal loss, the relative abundance of neuronal and glial lesions, the morphologic features of glial lesions, and the frequency of comorbid pathology. Both PSP and CBD have a wide spectrum of clinical manifestations, including disorders of movement and cognition. Recognition of phenotypic diversity in PSP and CBD may improve antemortem diagnostic accuracy, which tends to be very good for the most common presentation of PSP (Richardson syndrome), but poor for the most characteristic presentation of CBD (corticobasal syndrome: CBS). Development of molecular and imaging biomarkers may improve antemortem diagnostic accuracy. Currently, multidisciplinary symptomatic and supportive treatment with pharmacological and non-pharmacological strategies remains the standard of care. In the future, experimental therapeutic trials will be important to slow disease progression.

Neuropsychiatric Aspects of Frontotemporal Dementia

Frontotemporal dementia (FTD) encompasses a group of clinical syndromes, including behavioral-variant FTD, nonfluent variant primary progressive aphasia, semantic variant primary progressive aphasia, FTD motor neuron disease, progressive supranuclear palsy syndrome, and corticobasal syndrome. Early on in its course, FTD is commonly seen in psychiatric clinics. We review the clinical features and diagnostic criteria in FTD spectrum disorders.

Progressive supranuclear palsy: Advances in diagnosis and management

Progressive supranuclear palsy (PSP) is a complex clinicopathologic disease with no current cure or disease modulating therapies that can only be definitively confirmed at autopsy. Growing understanding of the phenotypic diversity of PSP has led to expanded clinical criteria and new insights into etiopathogenesis that coupled with improved in vivo biomarkers makes increased access to current clinical trials possible. Current standard-of-care treatment of PSP is multidisciplinary, supportive and symptomatic, and several trials of potentially disease modulating agents have already been completed with disappointing results. Current ongoing clinical trials target the abnormal aggregation of tau through a variety of mechanisms including immunotherapy and gene therapy offer a more direct method of treatment. Here we review PSP clinicopathologic correlations, in vivo biomarkers including MRI, PET, and CSF biomarkers. We additionally review current pharmacologic and non-pharmacologic methods of treatment, prior and ongoing clinical trials in PSP. Newly expanded clinical criteria and improved specific biomarkers will aid in identifying patients with PSP earlier and more accurately and expand access to these potentially beneficial clinical trials.

The Progressive Supranuclear Palsy: Past and Present Aspects

Objectives: Recently, new criteria for sensitive and specific clinical diagnosis of progressive supranuclear palsy (PSP) have been addressed while distinct clinical phenotypes of the disorder have been increasingly described in the literature. This study aimed to describe past and present aspects of the disease as well as to highlight the cognitive and behavioral profile of PSP patients in relation to the underlying pathology, genetics and treatment procedures.Methods: A Medline and Scopus search was performed to identify articles published on this topic. Articles published solely in English were considered.Results: The most common clinical characteristics of PSP included early postural instability and falls, vertical supranuclear gaze palsy, parkinsonism with poor response to levodopa and pseudobulbar palsy. Frontal dysfunction and verbal fluency deficits were the most distinct cognitive impairments in PSP while memory, visuospatial and social cognition could also be affected. Apathy and impulsivity were also present in PSP patients and had significant impact on relatives and caregivers.Conclusions: PSP is a neurodegenerative disorder with prominent tau neuropathology. Movement, motivation and communication impairments in patients with PSP may limit participation in everyday living activities. Comprehensive neuropsychological assessments are of significant importance for PSP cognitive evaluation. Pharmacologic and non-pharmacologic approaches could be applied in order to relieve patients and improve quality of life.Clinical Implications: Executive dysfunction is the most notable cognitive impairment and dominates the neuropsychological profile of patients with PSP.

Diagnosis Across the Spectrum of Progressive Supranuclear Palsy and Corticobasal Syndrome

Importance

Atypical parkinsonian syndromes (APS), including progressive supranuclear palsy (PSP), corticobasal syndrome (CBS), and multiple system atrophy (MSA), may be difficult to distinguish in early stages and are often misdiagnosed as Parkinson disease (PD). The diagnostic criteria for PSP have been updated to encompass a range of clinical subtypes but have not been prospectively studied.

Objective

To define the distinguishing features of PSP and CBS subtypes and to assess their usefulness in facilitating early diagnosis and separation from PD.

Design, Setting, Participants

This cohort study recruited patients with APS and PD from movement disorder clinics across the United Kingdom from September 1, 2015, through December 1, 2018. Patients with APS were stratified into the following groups: those with Richardson syndrome (PSP-RS), PSP-subcortical (including PSP-parkinsonism and progressive gait freezing subtypes), PSP-cortical (including PSP-frontal and PSP-CBS overlap subtypes), MSA-parkinsonism, MSA-cerebellar, CBS-Alzheimer disease (CBS-AD), and CBS-non-AD. Data were analyzed from February 1, through May 1, 2019.

Main Outcomes and Measures

Baseline group comparisons used (1) clinical trajectory; (2) cognitive screening scales; (3) serum neurofilament light chain (NF-L) levels; (4) TRIM11, ApoE, and MAPT genotypes; and (5) volumetric magnetic resonance imaging measures.

Results

A total of 222 patients with APS (101 with PSP, 55 with MSA, 40 with CBS, and 26 indeterminate) were recruited (129 [58.1%] male; mean [SD] age at recruitment, 68.3 [8.7] years). Age-matched control participants (n = 76) and patients with PD (n = 1967) were included for comparison. Concordance between the antemortem clinical and pathologic diagnoses was achieved in 12 of 13 patients with PSP and CBS (92.3%) undergoing postmortem evaluation. Applying the Movement Disorder Society PSP diagnostic criteria almost doubled the number of patients diagnosed with PSP from 58 to 101. Forty-nine of 101 patients with reclassified PSP (48.5%) did not have the classic PSP-RS subtype. Patients in the PSP-subcortical group had a longer diagnostic latency and a more benign clinical trajectory than those in PSP-RS and PSP-cortical groups. The PSP-subcortical group was distinguished from PSP-cortical and PSP-RS groups by cortical volumetric magnetic resonance imaging measures (area under the curve [AUC], 0.84-0.89), cognitive profile (AUC, 0.80-0.83), serum NF-L level (AUC, 0.75-0.83), and TRIM11 rs564309 genotype. Midbrain atrophy was a common feature of all PSP groups. Eight of 17 patients with CBS (47.1%) undergoing cerebrospinal fluid analysis were identified as having the CBS-AD subtype. Patients in the CBS-AD group had a longer diagnostic latency, relatively benign clinical trajectory, greater cognitive impairment, and higher APOE-ε4 allele frequency than those in the CBS-non-AD group (AUC, 0.80-0.87; P < .05). Serum NF-L levels distinguished PD from all PSP and CBS cases combined (AUC, 0.80; P < .05).

Conclusions and Relevance

These findings suggest that studies focusing on the PSP-RS subtype are likely to miss a large number of patients with underlying PSP tau pathology. Analysis of cerebrospinal fluid defined a distinct CBS-AD subtype. The PSP and CBS subtypes have distinct characteristics that may enhance their early diagnosis.

Progressive supranuclear palsy

Progressive supranuclear palsy (PSP) is a neurodegenerative disease characterized pathologically by 4 repeat tau deposition in various cell types and anatomical regions. Richardson's syndrome (RS) is the initially described and one of the clinical phenotypes associated with PSP pathology, characterized by vertical supranuclear gaze paly in particular downwards, postural instability with early falls and subcortical frontal dementia. PSP can manifest as several other clinical phenotypes, including PSP-parkinsonism, -pure akinesia with gait freezing, -frontotemporal dementia, - corticobasal syndrome, - speech/language impairment. RS can also have a pathologic diagnosis other than PSP, including corticobasal degeneration, FTD-TDP-43 and others. New clinical diagnostic criteria take into account this phenotypic variability in an attempt to diagnose the disease earlier, given the current lack of a validated biomarker. At present, therapeutic options for PSP are symptomatic and insufficient. Recent large neuroprotective trials have failed to provide a positive clinical outcome, however, have led to the design of better studies that are ongoing and hold promise for a neuroprotective treatment for PSP.

Urinary Symptoms in Patients with Parkinson's Disease and Progressive Supranuclear Palsy: Urodynamic Findings and Management of Bladder Dysfunction

Objective:

The objective of this study is to observe urinary symptoms in patients with Parkinson's disease (PD) and progressive supranuclear palsy (PSP) and advice bladder dysfunction management based on urodynamic study (UDS) findings.

Patients and Methods:

Twenty-two patients (12 males) with PD and PSP (15 and 7, respectively) with urinary symptoms were included in this study. All patients except one were on levodopa and carbidopa medication. UDS was performed, and bladder management determined.

Results:

Mean age was 60.4 years (range 41–73 years, standard deviation [SD] 8.4). Mean illness duration was 31.9 months (range 9–146 months, SD 31.0) and mean duration of urinary symptoms was 14.8 months (range 1–61 months, SD 15.8). Eighteen patients reported nocturia and 16 patients had urgency with or without urge incontinence. Three patients had retention and straining to void and 3 had mixed urinary complaints. Twelve out of 22 patients had absence of voluntary anal contraction on per-rectal examination. UDS was suggestive of 12 patients with neurogenic detrusor overactivity with or without sphincter dyssynergy. Six patients had normal detrusor pressure, and four patients were found to have contractile detrusor. Ten patients had significant postvoid residual. Bladder management included pharmacotherapy, supportive, and behavioral management as appropriate.

Conclusions:

Patients with PD/PSP are known to develop urinary symptoms during illness. Clinical complaints and UDS findings do not necessarily match. UDS is required to manage urinary symptoms. Most of the patients respond to oral antimuscarinic medications along with behavioral and supportive therapy.

Frontrunner in Translation: Progressive Supranuclear Palsy

Progressive supranuclear palsy (PSP) is a four-repeat tau proteinopathy. Abnormal tau deposition is not unique for PSP and is the basic pathologic finding in some other neurodegenerative disorders such as Alzheimer's disease (AD), age-related tauopathy, frontotemporal degeneration, corticobasal degeneration, and chronic traumatic encephalopathy. While AD research has mostly been focused on amyloid beta pathology until recently, PSP as a prototype of a primary tauopathy with high clinical-pathologic correlation and a rapid course is a crucial candidate for tau therapeutic research. Several novel approaches to slow disease progression are being developed. It is expected that the benefits of translational research in this disease will extend beyond the PSP population. This article reviews advances in the diagnosis, epidemiology, pathology, hypothesized etiopathogenesis, and biomarkers and disease-modifying therapeutic approaches of PSP that is leading it to become a frontrunner in translation.

Using gait analysis' parameters to classify Parkinsonism: A data mining approach

INTRODUCTION

Parkinson's disease (PD) is the second most common neurodegenerative disorder in the world, while Progressive Supranuclear Palsy (PSP) is an atypical Parkinsonism resembling PD, especially in early stage. Assumed that gait dysfunctions represent a major motor symptom for both pathologies, gait analysis can provide clinicians with subclinical information reflecting subtle differences between these diseases. In this scenario, data mining can be exploited in order to differentiate PD patients at different stages of the disease course and PSP using all the variables acquired through gait analysis.

METHODS

A cohort of 46 subjects (divided into three groups) affected by PD patients at different stages and PSP patients was acquired through gait analysis and spatial and temporal parameters were analysed. Synthetic Minority Over-sampling Technique was used to balance our imbalanced dataset and cross-validation was applied to provide different training and testing sets. Then, Random Forests and Gradient Boosted Trees were implemented.

RESULTS

Accuracy, error, precision, recall, specificity and sensitivity were computed for each group and for both algorithms, including 16 features. Random Forests obtained the highest accuracy (86.4%) but also specificity and sensitivity were particularly high, overcoming the 90% for PSP group.

CONCLUSION

The novelty of the study is the use of a data mining approach on the spatial and temporal parameters of gait analysis in order to classify patients affected by typical (PD) and atypical Parkinsonism (PSP) based on gait patterns. This application would be helpful for clinicians to distinguish PSP from PD at early stage, when the differential diagnosis is particularly challenging.

Midbrain atrophy in patients with presymptomatic progressive supranuclear palsy-Richardson's syndrome

INTRODUCTION

In the present study, midbrain atrophy and the pons-to-midbrain area ratio (P/M ratio) were investigated as diagnostic markers for presymptomatic progressive supranuclear palsy-Richardson's syndrome (Pre-PSP-RS).

METHODS

The present study included 27 patients with probable PSP-RS who underwent brain MRI at least twice before and after the development of clinical symptoms, age- and sex-matched participants with Parkinson's disease (PD, n = 27), and healthy controls (n = 27). The midbrain area, pons area, and P/M ratio of the Pre-PSP-RS, PD, and control subjects were measured using midsagittal images from brain MRI, and the parameters were compared among the groups.

RESULTS

The midbrain area decreased and the P/M ratio increased significantly in the Pre-PSP-RS patients compared with both the PD and control subjects (midbrain, Pre-PSP-RS vs. PD = 1.01 cm²vs. 1.29 cm², p < 0.001, Pre-PSP-RS vs. controls = 1.01 cm²vs. 1.29 cm², p < 0.001; P/M ratio, Pre-PSP-RS vs. PD = 5.27 vs. 4.03, p < 0.001, Pre-PSP-RS vs. controls = 5.27 cm²vs. 4.06 cm², p < 0.001). The P/M ratio had high sensitivity (vs. PD, 96.3%, vs. control, 88.9%) and specificity (vs. PD, 81.5%, vs. control, 96.3%) in differentiating Pre-PSP-RS patients from PD and control subjects.

CONCLUSION

Midbrain atrophy precedes the clinical symptoms of PSP-RS and could be a useful diagnostic imaging biomarker for Pre-PSP-RS. Furthermore, this information could play an important role in the development of future treatment strategies.

Genome-wide survey of copy number variants finds MAPT duplications in progressive supranuclear palsy

BACKGROUND

Progressive supranuclear palsy is a neurodegenerative tauopathy manifesting clinically as a progressive akinetic-rigid syndrome. In this study, we sought to identify genetic variants influencing PSP susceptibility through a genome-wide association analysis of a cohort of well-characterized patients who had participated in the Neuroprotection and Natural History in Parkinson Plus Syndromes and Blood Brain Barrier in Parkinson Plus Syndromes studies.

METHODS

We genotyped single-nucleotide polymorphisms in 283 PSP cases from the United Kingdom, Germany, and France and compared these with genotypes from 4472 controls. Copy number variants were identified from genotyping data.

RESULTS

We observed associations on chromosome 17 within or close to the MAPT gene and explored the genetic architecture at this locus. We confirmed the previously reported association of rs1768208 in the MOBP gene (P = 3.29 × 10^-13 ) and rs1411478 in STX6 (P = 3.45 × 10^-10 ). The population-attributable risk from the MAPT, MOBP, and STX6 single-nucleotide polymorphisms was found to be 0.37, 0.26, and 0.08, respectively. In addition, we found 2 instances of copy number variants spanning the MAPT gene in patients with PSP. These copy number variants include tau but few other genes within the chromosome 17 haplotype region, providing additional support for the direct pathogenicity of MAPT in PSP.

CONCLUSIONS

Clinicians should also be aware of MAPT duplication as a possible genetic cause of PSP, especially in patients presenting with young age at onset. © 2019 International Parkinson and Movement Disorder Society.

A Home-Based, Music-Cued Movement Program Is Feasible and May Improve Gait in Progressive Supranuclear Palsy

Objectives: To understand the benefits and feasibility of using supervised, home-based, music-cued training to improve gait speed and stability in community-dwelling people with Progressive Supranuclear Palsy.

Design: Feasibility trial incorporating a single group repeated-measures design.

Setting: Human movement laboratory and participants' homes.

Interventions:Two training sessions per week, conducted by experienced physiotherapists over 4 weeks. Each home training session consisted of a range of activities in standing or walking, with, and without auditory cues. Rhythmic auditory cues were played via a portable digital music player and consisted of metronome beats and individually chosen, commercially available rhythmic music tracks.

Main Outcome Measures: Spatiotemporal gait measures were recorded using an 8 m long GAITRite® mat. Participants walked without cues at self-selected comfortable pace. The Progressive Supranuclear Palsy and Unified Parkinson's Disease Rating Scales were administered at baseline. Addenbrooke's Cognitive Examination-III, Geriatric Depression Scale, Assessment of Personal Music Preference Scale, and Physiological Profile Assessment were administered at baseline and retest.

Results: At baseline, two of the five community-dwelling participants with Progressive Supranuclear Palsy walked with normal speed and low gait variability. Of the remainder who walked with slower, more variable patterns, two walked faster at retest, one by a clinically meaningful amount. Four participants reduced their timing variability at retest and three reduced step length variability. All participants reported high satisfaction levels with the program.

Conclusions: When delivered at home with the support of caregivers, music-cued gait training can provide a feasible approach to improving disorders of gait stability in people with this rare, degenerative condition. Movement to music is engaging and enjoyable which can facilitate adherence to therapy.

Clinical Trial Registration : ANZCTR 12616000851460. http://www.anzctr.org.au/

Cognitive and behavioural dysfunctions in a patient with progressive supranuclear palsy (PSP)

Background

The aim of the case study was to describe the profile of cognitive and emotional functioning of a patient with possible progressive supranuclear palsy (PSP) from a longitudinal perspective.

Participants and procedure

This study involved an 71-year-old male patient diagnosed with PSP, and 9 matched healthy subjects. Neuro-psychological examination of the patient was performed twice with a 6 month interval. A set of neuropsycho-logical tests was used to assess both cognition and behaviour.

Results

Neuropsychological assessment revealed executive dysfunction dominance (planning deficits, reduced cogni-tive flexibility and abstract thinking, impulsiveness), reduced verbal fluency, psychomotor slowness and prob-lems with memory retrieval from the long-term memory storage in contrast to significantly better recognition of the previously learned information. According to emotional functioning, frontal change of personality was ob-served, with apathy, disinhibition, lack of insights, impulsiveness and “utilization behaviours”.

Conclusions

The profile of emotional and cognitive impairments met the criteria for dementia. There was a progression of deficits at visit two in comparison to visit one. The longitudinal perspective allowed the dynamics of emotional, cognitive and behavioural changes to be described over time: from depression related to initially preserved criticism of the illness to apathy and emotional blunting and behavioural frontal syndrome connected with the systematic loss of insight.

Recognizing and treating atypical Parkinson disorders

Though less common than Parkinson's disease (PD), the atypical Parkinson disorders such as such as dementia with Lewy bodies, multiple system atrophy, progressive supranuclear palsy, and corticobasal degeneration are increasingly recognized and important to distinguish from PD. Atypical or "Parkinson-plus" disorders are multisystem disorders and generally progress more rapidly and respond poorly to current therapies compared to PD. Recent advances in our understanding of the pathophysiology of these disorders, however, have generated new interest in the development of novel diagnostics and disease-modifying therapeutics aimed at identifying and treating these disorders. In this review we discuss the clinical approach to the atypical Parkinson disorders and the recent developments in diagnostic and research criteria that take into account the phenotypic heterogeneity and advances in our understanding of the pathophysiology of these disorders.

Tauopathy-associated PERK alleles are functional hypomorphs that increase neuronal vulnerability to ER stress

Tauopathies are neurodegenerative diseases characterized by tau protein pathology in the nervous system. EIF2AK3 (eukaryotic translation initiation factor 2 alpha kinase 3), also known as PERK (protein kinase R-like endoplasmic reticulum kinase), was identified by genome-wide association study as a genetic risk factor in several tauopathies. PERK is a key regulator of the Unfolded Protein Response (UPR), an intracellular signal transduction mechanism that protects cells from endoplasmic reticulum (ER) stress. PERK variants had previously been identified in Wolcott-Rallison Syndrome, a rare autosomal recessive metabolic disorder, and these variants completely abrogated the function of PERK's kinase domain or prevented PERK expression. In contrast, the PERK tauopathy risk variants were distinct from the Wolcott-Rallison variants and introduced missense alterations throughout the PERK protein. The function of PERK tauopathy variants and their effects on neurodegeneration are unknown. Here, we discovered that tauopathy-associated PERK alleles showed reduced signaling activity and increased PERK protein turnover compared to protective PERK alleles. We found that iPSC-derived neurons carrying PERK risk alleles were highly vulnerable to ER stress-induced injury with increased tau pathology. We found that chemical inhibition of PERK in human iPSC-derived neurons also increased neuronal cell death in response to ER stress. Our results indicate that tauopathy-associated PERK alleles are functional hypomorphs during the UPR. We propose that reduced PERK function leads to neurodegeneration by increasing neuronal vulnerability to ER stress-associated damage. In this view, therapies to enhance PERK signaling would benefit at-risk carriers of hypomorphic alleles.

Joint genome-wide association study of progressive supranuclear palsy identifies novel susceptibility loci and genetic correlation to neurodegenerative diseases

Background

Progressive supranuclear palsy (PSP) is a rare neurodegenerative disease for which the genetic contribution is incompletely understood.

Methods

We conducted a joint analysis of 5,523,934 imputed SNPs in two newly-genotyped progressive supranuclear palsy cohorts, primarily derived from two clinical trials (Allon davunetide and NNIPPS riluzole trials in PSP) and a previously published genome-wide association study (GWAS), in total comprising 1646 cases and 10,662 controls of European ancestry.

Results

We identified 5 associated loci at a genome-wide significance threshold P < 5 × 10^− 8, including replication of 3 loci from previous studies and 2 novel loci at 6p21.1 and 12p12.1 (near RUNX2 and SLCO1A2, respectively). At the 17q21.31 locus, stepwise regression analysis confirmed the presence of multiple independent loci (localized near MAPT and KANSL1). An additional 4 loci were highly suggestive of association (P < 1 × 10^− 6). We analyzed the genetic correlation with multiple neurodegenerative diseases, and found that PSP had shared polygenic heritability with Parkinson’s disease and amyotrophic lateral sclerosis.

Conclusions

In total, we identified 6 additional significant or suggestive SNP associations with PSP, and discovered genetic overlap with other neurodegenerative diseases. These findings clarify the pathogenesis and genetic architecture of PSP.

Electronic supplementary material

The online version of this article (10.1186/s13024-018-0270-8) contains supplementary material, which is available to authorized users.