Stage-Dependent Biomarker Changes in Spinocerebellar Ataxia Type 3.

Spinocerebellar ataxia type 3/Machado-Joseph disease is the most common autosomal dominant ataxia. In view of the development of targeted therapies, knowledge of early biomarker changes is needed. We analyzed cross-sectional data of 292 spinocerebellar ataxia type 3/Machado-Joseph disease mutation carriers. Blood concentrations of mutant ATXN3 were high before and after ataxia onset, whereas neurofilament light deviated from normal 13.3 years before onset. Pons and cerebellar white matter volumes decreased and deviated from normal 2.2 years and 0.6 years before ataxia onset. We propose a staging model of spinocerebellar ataxia type 3/Machado-Joseph disease that includes a biomarker stage characterized by objective indicators of neurodegeneration before ataxia onset. ANN NEUROL 2024;95:400-406.

Predictors of Survival in Friedreich's Ataxia: A Prospective Cohort Study.

BACKGROUND: Friedreich's ataxia (FA) is a rare multisystemic disorder which can cause premature death. OBJECTIVES: To investigate predictors of survival in FA. METHODS: Within a prospective registry established by the European Friedreich's Ataxia Consortium for Translational Studies (EFACTS; ClinicalTrials.gov identifier NCT02069509) we enrolled genetically confirmed FA patients at 11 tertiary centers and followed them in yearly intervals. We investigated overall survival applying the Kaplan-Meier method, life tables, and log-rank test. We explored prognostic factors applying Cox proportional hazards regression and subsequently built a risk score which was assessed for discrimination and calibration performance. RESULTS: Between September 2010 and March 2017, we enrolled 631 FA patients. Median age at inclusion was 31 (range, 6-76) years. Until December 2022, 44 patients died and 119 terminated the study for other reasons. The 10-year cumulative survival rate was 87%. In a multivariable analysis, the disability stage (hazard ratio [HR] 1.51, 95% CI 1.08-2.12, P = 0.02), history of arrhythmic disorder (HR 2.93, 95% CI 1.34-6.39, P = 0.007), and diabetes mellitus (HR 2.31, 95% CI 1.05-5.10, P = 0.04) were independent predictors of survival. GAA repeat lengths did not improve the survival model. A risk score built on the previously described factors plus the presence of left ventricular systolic dysfunction at echocardiography enabled identification of four trajectories to prognosticate up to 10-year survival (log-rank test P < 0.001). CONCLUSIONS: Arrhythmias, progressive neurological disability, and diabetes mellitus influence the overall survival in FA. We built a survival prognostic score which identifies patients meriting closer surveillance and who may benefit from early invasive cardiac monitoring and therapy. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Quantitative Speech Assessment in Ataxia-Consensus Recommendations by the Ataxia Global Initiative Working Group on Digital-Motor Markers.

Dysarthria is a common and debilitating symptom of many neurodegenerative diseases, including those resulting in ataxia. Changes to speech lead to significant reductions in quality of life, impacting the speaker in most daily activities. Recognition of its importance as an objective outcome measure in clinical trials for ataxia is growing. Its viability as an endpoint across the disease spectrum (i.e. pre-symptomatic onwards) means that trials can recruit ambulant individuals and later-stage individuals who are often excluded because of difficulty completing lower limb tasks. Here we discuss the key considerations for speech testing in clinical trials including hardware selection, suitability of tasks and their role in protocols for trials and propose a core set of tasks for speech testing in clinical trials. Test batteries could include forms suitable for remote short, sensitive and easy to use, with norms available in several languages. The use of artificial intelligence also could improve accuracy and automaticity of analytical pipelines in clinic and trials.

Comparison of Live and Remote Video Ratings of the Scale for Assessment and Rating of Ataxia.

Background: Video recordings of neurological examinations are often used in clinical trials. The Scale for Assessment and Rating of Ataxia (SARA) is a widely used clinical scale for ataxic patients. Despite several advantages of video ratings, correlation between live ratings and remote video-ratings has not been systematically investigated. Objective: To compare live and remote video assessment of SARA. Methods: Full SARA examinations of 69 patients with cerebellar ataxia were recorded on video. Live rating from site investigators were compared with remote video rating of three experienced ataxia clinicians using Bland-Altman analysis. Results: Live and remote video ratings showed a high level of agreement for the complete score (bias = 0.09, with standard deviation = 2.00) and all single SARA items (bias <0.20 for all items). Conclusion: Remote video ratings of SARA are a reliable means to assess severity of ataxia.

Patient-reported, health economic and psychosocial outcomes in patients with Friedreich ataxia (PROFA): protocol of an observational study using momentary data assessments via mobile health app.

INTRODUCTION: Friedreich ataxia (FA) is the most common hereditary ataxia in Europe, characterised by progressively worsening movement and speech impairments with a typical onset before the age of 25 years. The symptoms affect the patients' health-related quality of life (HRQoL) and psychosocial health. FA leads to an increasing need for care, associated with an economic burden. Little is known about the impact of FA on daily lives and HRQoL. To fill that gap, we will assess patient-reported, psychosocial and economic outcomes using momentary data assessment via a mobile health application (app). METHODS AND ANALYSIS: The PROFA Study is a prospective observational study. Patients with FA (n=200) will be recruited at six European study centres (Germany, France and Austria). We will interview patients at baseline in the study centre and subsequently assess the patients' health at home via mobile health app. Patients will self-report ataxia severity, HRQoL, speech and hearing disabilities, coping strategies and well-being, health services usage, adverse health events and productivity losses due to informal care on a daily to monthly basis on the app for 6 months. Our study aims to (1) validate measurements of HRQoL and psychosocial health, (2) assess the usability of the mobile health app, and (3) use descriptive and multivariate statistics to analyse patient-reported and economic outcomes and the interaction effects between these outcomes. Insights into the app's usability could be used for future studies using momentary data assessments to measure outcomes of patients with FA. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the Ethics Committee of the University Medicine of Greifswald, (BB096/22a, 26 October 2022) and from all local ethics committees of the participating study sites. Findings of the study will be published in peer-reviewed journals, presented at relevant international/national congresses and disseminated to German and French Patient Advocacy Organizations. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT05943002); Pre-results.

Stage-dependent biomarker changes in spinocerebellar ataxia type 3.

Spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3) is the most common autosomal dominant ataxia. In view of the development of targeted therapies for SCA3, precise knowledge of stage-dependent fluid and MRI biomarker changes is needed. We analyzed cross-sectional data of 292 SCA3 mutation carriers including 57 pre-ataxic individuals, and 108 healthy controls from the European Spinocerebellar ataxia type 3/Machado-Joseph Disease Initiative (ESMI) cohort. Blood concentrations of mutant ATXN3 and neurofilament light (NfL) were determined, and volumes of pons, cerebellar white matter (CWM) and cerebellar grey matter (CGM) were measured on MRI. Mutant ATXN3 concentrations were high before and after ataxia onset, while NfL continuously increased and deviated from normal 11.9 years before onset. Pons and CWM volumes decreased, but the deviation from normal was only 2.0 years (pons) and 0.3 years (CWM) before ataxia onset. We propose a staging model of SCA3 that includes an initial asymptomatic carrier stage followed by the biomarker stage defined by absence of ataxia, but a significant rise of NfL. The biomarker stage leads into the ataxia stage, defined by manifest ataxia. The present analysis provides a robust framework for further studies aiming at elaboration and differentiation of the staging model of SCA3.

The Diagnostic Value of Cerebrospinal Fluid Lactate for Detection of Sepsis in Community-Acquired Bacterial Meningitis.

Community-acquired bacterial meningitis conveys significant morbidity and mortality due to intracranial and systemic complications, and sepsis is a major contributor to the latter. While cerebrospinal fluid (CSF) analysis is essential in the diagnosis of bacterial meningitis, its predictive utility for detection of sepsis is unknown. We investigated the diagnostic performance of CSF parameters for sepsis defined by the Sepsis-3 criteria in a retrospective cohort of patients with community-acquired bacterial meningitis. Among 103 patients, 69.5% developed sepsis. CSF lactate was associated with sepsis with an odds ratio of 1.11 (p = 0.022), while CSF cell counts, glucose and protein levels were not (all p > 0.4). Employing the optimal cutoff of 8.2 mmol/L, elevated CSF lactate resulted in a sensitivity of 81.5% and specificity of 61.5% for sepsis. In exploratory analyses, CSF lactate was also associated with in-hospital mortality with an odds ratio of 1.21 (p = 0.011). Elevated CSF lactate might contribute to early diagnosis of sepsis as well as prognostication in patients with community-acquired bacterial meningitis.

Scale for the Assessment and Rating of Ataxia (SARA): Development of a Training Tool and Certification Program.

Monitoring of disease severity is of great importance for treatment and management of clinical trials. The Scale for Assessment and Rating of Ataxia (SARA) is a frequently used, short and easily applicable clinical scale used to assess the severity of ataxia. The objective of our study was to develop a training and certification tool for the SARA. SARA scores were recorded according to a standardized protocol and rated by three clinical experts in consensus. Four hundred thirty-eight videos of 67 patients were included in the SARA training tool. The tutorial section demonstrates a complete SARA examination on a healthy control. In the training section, users can compare their ratings to consensus ratings and access a video library covering the complete SARA range. The tool also includes a section that allows optional certification. The SARA training tool provides comprehensive and standardized training material and certification to reduce variability in applying the SARA. Standardization aims to improve the quality of patient care and research in ataxia.

Evolution of Clinical Outcome Measures and Biomarkers in Sporadic Adult-Onset Degenerative Ataxia.

BACKGROUND: Sporadic adult-onset ataxias without known genetic or acquired cause are subdivided into multiple system atrophy of cerebellar type (MSA-C) and sporadic adult-onset ataxia of unknown etiology (SAOA). OBJECTIVES: To study the differential evolution of both conditions including plasma neurofilament light chain (NfL) levels and magnetic resonance imaging (MRI) markers. METHODS: SPORTAX is a prospective registry of sporadic ataxia patients with an onset >40 years. Scale for the Assessment and Rating of Ataxia was the primary outcome measure. In subgroups, blood samples were taken and MRIs performed. Plasma NfL was measured via a single molecule assay. Regional brain volumes were automatically measured. To assess signal changes, we defined the pons and middle cerebellar peduncle abnormality score (PMAS). Using mixed-effects models, we analyzed changes on a time scale starting with ataxia onset. RESULTS: Of 404 patients without genetic diagnosis, 130 met criteria of probable MSA-C at baseline and 26 during follow-up suggesting clinical conversion to MSA-C. The remaining 248 were classified as SAOA. At baseline, NfL, cerebellar white matter (CWM) and pons volume, and PMAS separated MSA-C from SAOA. NfL decreased in MSA-C and did not change in SAOA. CWM and pons volume decreased faster, whereas PMAS increased faster in MSA-C. In MSA-C, pons volume had highest sensitivity to change, and PMAS was a predictor of faster progression. Fulfillment of possible MSA criteria, NfL and PMAS were risk factors, CWM and pons volume protective factors for conversion to MSA-C. CONCLUSIONS: This study provides detailed information on differential evolution and prognostic relevance of biomarkers in MSA-C and SAOA. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Scale for the assessment and rating of ataxia: Age-dependent performance of healthy adults.

BACKGROUND AND PURPOSE: The Scale for Assessment and Rating of Ataxia (SARA) is a widely used clinical scale. The objective was to study the age dependence of SARA in healthy adults and to define age-specific cut-off values to differentiate healthy from ataxic individuals. METHODS: Data from 390 healthy individuals and 119 spinocerebellar ataxia patients were analyzed. SARA scores were mapped on functional SARA (fSARA). Age-adjusted cut-off values were determined by receiver operating characteristic curve analysis. RESULTS: The cut-off value was 3 for SARA and 1.5 for fSARA. Older patients had higher SARA cut-off values (4.5 for 60-69 years and 6.5 for 70-79 years). Age-adjusted cut-off values for fSARA are 1 for 18-29, 30-39 and 50-59 years, 2 for 40-49 and 60-69 years and 3 for 70-79 years. Sensitivity and specificity were higher for SARA than for fSARA. CONCLUSION: In this study, age-dependent cut-off values were defined for SARA and fSARA. The results may be relevant for the design of future preventive trials in spinocerebellar ataxias that use conversion to ataxia as an outcome.

Retinal ganglion cell and microvascular density loss in hereditary spastic paraplegia.

Background: Hereditary spastic paraplegia (HSP) is characterized by progressive degeneration of distal axons in the long corticospinal tracts. Loss of retinal cells and microvascular networks has neither been suspected nor investigated. We concurrently examined the retinal microvasculature and retinal layer morphology in patients with HSP to assess whether retinal features may portray disease and its progression. Methods: Fifteen patients with HSP and 30 healthy controls were included in this cross-sectional case-control study. Disease severity was assessed with the Spastic Paraplegia Rating Scale (SPRS). Severity of ataxia was determined by the Scale for the Assessment and Rating of Ataxia (SARA). Retinal microvasculature was measured by means of optical coherence tomography angiography (OCT-A) and morphology of retinal layers using structural OCT. Mixed-effects models were applied for data analysis. Results: HSP patients showed significantly reduced vessel density of the superficial vascular plexus (SVP), reduced ganglion cell layer (GCL) volume, reduced inner plexiform layer (IPL) volume and reduced temporal-inferior peripapillary retinal nerve fiber layer (pRNFL) thickness versus healthy controls. GCL volume reduction correlated significantly with the worsening of visual acuity and higher SARA scores. Conclusions: These findings demonstrate that, in HSP both cells and vascular networks of the retina are compromised. Assessment of the retinal GCL, IPL and SVP may aid in diagnosis and monitoring of disease progression as well as provide novel structural outcome measures for clinical trials.

Isolated slow orthostatic tremor of the trunk.

Slow orthostatic tremor is an extremely rare movement disorder with relatively low-frequency tremor (< 13 Hz) in the legs and trunk, which is evoked by standing. There is still much controversy regarding its precise etiology. Here we present a 57 year-old female patient with a slow orthostatic tremor variant who experienced progressive gait disturbances since six years due to isolated trunk tremor. Potential symptomatic causes of tremor and other neurological co-morbidities were excluded through an exenstive clinical, laboratoy and imaging work-up. Subsequently, a combined treatment with propranolol and primidone was started, which resulted in almost complete resolution of the trunk tremor. Given that the slow trunk tremor in this patient almost completely resolved after therapy with a low-dose propranolol and primidone, considered first line drugs for the treatment of essential tremor, this case illustrates that isolated orthostatic trunk tremor may occur as a rare variant of essential tremor.

Development of SARAhome , a New Video-Based Tool for the Assessment of Ataxia at Home.

BACKGROUND: Clinical scales such as the Scale for the Assessment and Rating of Ataxia (SARA) cannot be used to study ataxia at home or to assess daily fluctuations. The objective of the current study was to develop a video-based instrument, SARAhome , for measuring ataxia severity easily and independently at home. METHODS: Based on feasibility of self-application, we selected 5 SARA items (gait, stance, speech, nose-finger test, fast alternating hand movements) for SARAhome (range, 0-28). We compared SARAhome items with total SARA scores in 526 patients with spinocerebellar ataxia types 1, 2, 3, and 6 from the EUROSCA natural history study. To prospectively validate the SARAhome , we directly compared the self-applied SARAhome and the conventional SARA in 50 ataxia patients. To demonstrate feasibility of independent home recordings in a pilot study, 12 ataxia patients were instructed to obtain a video each morning and evening over a period of 14 days. All videos were rated offline by a trained rater. RESULTS: SARAhome extracted from the EUROSCA baseline data was highly correlated with conventional SARA (r = 0.9854, P < 0.0001). In the prospective validation study, the SARAhome was highly correlated with the conventional SARA (r = 0.9254, P < 0.0001). Five of 12 participants of the pilot study obtained a complete set of 28 evaluable videos. Seven participants obtained 13-27 videos. The intraindividual differences between the lowest and highest SARAhome scores ranged from 1 to 5.5. CONCLUSION: The SARAhome and the conventional SARA are highly correlated. Application at home is feasible. There was a considerable degree of intraindividual variability of the SARAhome scores. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Remarkable improvement of primary orthostatic tremor using perampanel.

Management of primary orthostatic tremor (POT) remains challenging, and medication is often ineffective. We report the case of a 53-year-old female with orthostatic tremor for 6 years who was refractory to gabapentin, clonazepam, primidone and propranolol. After treatment with 4 mg/day perampanel, she reported almost complete resolution of tremor. The diagnosis of POT was confirmed by tremor analysis using surface electromyography. Our report shows the potential use of the novel AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptor antagonist perampanel for the treatment of POT. To date, only two similar patients, one refractory to treatment and the other previously treated with clonazepam only, have been reported. We would like to note that our patient was refractory to all previous therapy and responded to a low dose of perampanel without side effects. The striking clinical improvement suggests a putative role of glutamate in the pathophysiology of orthostatic tremor.

Recurrent Pontine Strokes in a Young Male.

A 34-year-old patient presented to the emergency department with recurrent neurologic symptoms of sudden onset. MRI showed white matter hyperintensities consistent with small vessel disease, predominantly in the pons. There were no known cardiovascular risk factors (CVRF) and extensive workup for vasculitis was negative. The preliminary diagnosis was small vessel primary central nervous system vasculitis, but immunosuppressive treatment did not stop a progression of the disease over 6 months. Repeated negative diagnostic workup for vasculitis, lack of response to therapy, young age, and predominant involvement of the pons were compatible with pontine autosomal dominant microangiopathy and leukoencephalopathy (PADMAL), which is a very rare monogenic cause of cerebral small vessel disease due to upregulation of collagen type-IV. Correspondingly, a COL4A1 mutation was found. Therapy was immediately stopped in favour of more strict adjustment of the CVRF including lowering of LDL < 70 mg/dl and extensive monitoring of blood-pressure.

Effects of Rivastigmine on Patients with Spinocerebellar Ataxia Type 3: A Case Series of Five Patients.

BACKGROUND: Rivastigmine is an acetylcholine esterase inhibitor which is commonly used as therapy for dementia in Alzheimer's disease and Parkinson's disease (PD). Recently, a randomized controlled trial demonstrated a positive effect of rivastigmine on gait function in nondemented PD patients. Disturbed gait is a shared hallmark of PD and ataxias. OBJECTIVES: We hypothesized that the effect of rivastigmine could be translated to spinocerebellar ataxia (SCA) improving gait function. METHOD: Five patients with SCA type 3 were treated with transdermal rivastigmine for 8 weeks. The patients were monitored using the Scale for the Assessment and Rating of Ataxia (SARA) and an electronic walkway system (GAITRite®). RESULTS: Gait function was not changed by treatment, but 4 patients who continued treatment for 8 weeks showed improved coordination of extremities. The SARA sum score, which was 7.6 ± 2.2 at baseline, had dropped by 1.5 ± 1.9 after 4 weeks and by 2.1 ± 1.4 after 8 weeks. CONCLUSIONS: Contrary to our hypothesis, we observed no improvement of gait parameters as assessed by SARA and GAIT-Rite®, but coordination abilities were improved. Rivastigmine was well tolerated, but known side effects of rivastigmine, such as deterioration of asthma, may appear. Further trials in larger cohorts are needed to confirm our findings.