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"Singer, Wolfgang"
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COMPASS 31: A Refined and Abbreviated Composite Autonomic Symptom Score
2012
To develop a concise and statistically robust instrument to assess autonomic symptoms that provides clinically relevant scores of autonomic symptom severity based on the well-established 169-item Autonomic Symptom Profile (ASP) and its validated 84-question scoring instrument, the Composite Autonomic Symptom Score (COMPASS).
We assessed the internal consistency of COMPASS using Cronbach α coefficients based on the ASP of 405 healthy control subjects recruited and seen in the Mayo Clinic Autonomic Disorders Center between March 1, 1995, and March 31, 2010. Applying a simplified scoring algorithm, we then used exploratory factor analysis with orthogonal rotation and eigenvalue calculations to extract internally consistent domains and to reduce dimensionality. This analysis was followed by expert revisions to eliminate redundant content and to retain clinically important questions and final assessment of the new instrument.
The new simplified scoring algorithm alone resulted in higher Cronbach α values in all domains. Factor analysis revealed 7 domains with a total of 54 questions retained. Expert revisions resulted in further reduction of questions and domains with a remaining total of 31 questions in 6 domains (COMPASS 31). Measures of internal consistency were much improved compared to those for COMPASS. Following appropriate weighting, this instrument provides an autonomic symptom score from 0 to 100.
COMPASS 31 is a refined, internally consistent, and markedly abbreviated quantitative measure of autonomic symptoms. It is based on the original ASP and COMPASS, applies a much simplified scoring algorithm, and is suitable for widespread use in autonomic research and practice.
Journal Article
Natural history of multiple system atrophy in the USA: a prospective cohort study
by
Jankovic, Joseph
,
Low, Phillip A
,
Marshall, Frederick J
in
Activities of Daily Living - psychology
,
Adult
,
Aged
2015
Multiple system atrophy is a rare, fatal neurodegenerative disorder with symptoms of autonomic failure plus parkinsonism, cerebellar ataxia, or both. We report results of the first prospective natural history study of multiple system atrophy in the USA, and the effects of phenotype and autonomic failure on prognosis.
We recruited participants with probable multiple system atrophy—of either the parkinsonism subtype (MSA-P) or the cerebellar ataxia subtype (MSA-C)—at 12 neurology centres in the USA specialising in movement or autonomic disorders. We followed up patients every 6 months for 5 years and assessed them with the Unified Multiple System Atrophy Rating Scale part I (UMSARS I; a functional score of symptoms and ability to undertake activities of daily living), UMSARS II (neurological motor evaluation), and the Composite Autonomic Symptoms Scale (COMPASS)-select (a measure of autonomic symptoms and autonomic functional status). We assessed potential predictors of outcome. We used Cox proportional hazards models to calculate univariate hazard ratios for shorter survival using age at disease onset as a continuous variable and sex, clinical phenotype, and early development of neurological and autonomic manifestations as categorical variables.
We recruited 175 participants. Mean age at study entry was 63·4 years (SD 8·6). Median survival from symptom onset was 9·8 years (95% CI 8·8–10·7) and median survival from enrolment was 1·8 years (0·9–2·7). Participants with severe symptomatic autonomic failure (symptomatic orthostatic hypotension, urinary incontinence, or both) at diagnosis (n=62) had a worse prognosis than those without severe disease (n=113; median survival 8·0 years, 95% CI 6·5–9·5 vs 10·3 years, 9·3–11·4; p=0·021). At baseline, patients with MSA-P (n=126) and MSA-C (n=49) had much the same symptoms and functional status: mean UMSARS I 25·2 (SD 8·08) versus 24·6 (8·34; p=0·835); mean UMSARS II 26·4 (8·8) versus 25·4 (10·5; p=0·764); COMPASS-select 43·5 (18·7) versus 42·8 (19·6; p=0·835). Progression over 5 years, assessed by change in UMSARS I, UMSARS II, and COMPASS-select, was modest.
Probable multiple system atrophy is a late-stage disease with short survival. The natural histories of MSA-P and MSA-C are similar and severe symptomatic autonomic failure at diagnosis is associated with worse prognosis.
US National Institutes of Health, Mayo Clinic, and Kathy Shih Memorial Foundation.
Journal Article
Alpha-synuclein seeding amplification assays in Lewy body dementia: a brief review
by
McLean, Pamela J.
,
Kaya, Zeynep Bengisu
,
Singer, Wolfgang
in
Advertising executives
,
Alpha-synuclein
,
alpha-Synuclein - analysis
2025
Lewy body dementia (LBD), which includes dementia with Lewy bodies (DLB) and Parkinson’s disease dementia (PDD), is characterized by cognitive decline, sleep disturbances, motor dysfunction, and other debilitating clinical symptoms. Neuropathologically, LBD is characterized by the progressive accumulation of alpha-synuclein (aSYN) in vulnerable cellular populations in the brain. Diagnosing LBD is challenging due to the overlap of clinical symptoms with Alzheimer’s disease (AD) and other neurodegenerative disorders with current diagnostic tools, including clinical examinations by specialized neurologists and brain imaging, limited by accessibility. Taken together, LBD is often misdiagnosed, especially at early disease stages. Seed amplification assays to detect pathogenic aSYN (aSYN SAAs) are emerging as promising tools to detect aSYN pathology in biological specimens. These assays amplify trace amounts of misfolded aSYN, enabling their potential detection in brain, CSF, saliva, skin, and blood. This review compares the sensitivity and specificity of aSYN SAAs across different biological samples and explores the potential of the assay as a diagnostic in LBD. We also highlight challenges that will need to be addressed going forward if the aSYN SAA is to be widely adopted as a diagnostic test. Despite current limitations, aSYN SAAs hold promise for early and precise diagnosis, paving the way for targeted treatments that could significantly improve patient care and outcomes.
Journal Article
Management of neurogenic orthostatic hypotension: an update
2008
Orthostatic hypotension (OH) is common in elderly people and in patients with disorders such as diabetes and Parkinson's disease. Grading of the severity of OH and its effect on the patient's quality of life are important. The symptoms vary with orthostatic stress, and subtle symptoms such as tiredness and cognitive impairment should be recognised. Standard drug treatment for OH is effective but worsens supine hypertension, whereas pyridostigmine can improve OH slightly but significantly without worsening of supine hypertension. Because orthostatic stress varies from moment to moment and drug treatment is suboptimal, drug treatment of OH needs to be combined with non-pharmacological approaches, such as compression of venous capacitance beds, use of physical counter-manoeuvres, and intermittent water-bolus treatment.
Journal Article
Efficacy and safety of rifampicin for multiple system atrophy: a randomised, double-blind, placebo-controlled trial
by
Cheshire, William
,
Low, Phillip A
,
Dupont, William D
in
Aged
,
Cohort Studies
,
Colleges & universities
2014
No available treatments slow or halt progression of multiple system atrophy, which is a rare, progressive, fatal neurological disorder. In a mouse model of multiple system atrophy, rifampicin inhibited formation of α-synuclein fibrils, the neuropathological hallmark of the disease. We aimed to assess the safety and efficacy of rifampicin in patients with multiple system atrophy.
In this randomised, double-blind, placebo-controlled trial we recruited participants aged 30–80 years with possible or probable multiple system atrophy from ten US medical centres. Eligible participants were randomly assigned (1:1) via computer-generated permuted block randomisation to rifampicin 300 mg twice daily or matching placebo (50 mg riboflavin capsules), stratified by subtype (parkinsonian vs cerebellar), with a block size of four. The primary outcome was rate of change (slope analysis) from baseline to 12 months in Unified Multiple System Atrophy Rating Scale (UMSARS) I score, analysed in all participants with at least one post-baseline measurement. This study is registered with ClinicalTrials.gov, number NCT01287221.
Between April 22, 2011, and April 19, 2012, we randomly assigned 100 participants (50 to rifampicin and 50 to placebo). Four participants in the rifampicin group and five in the placebo group withdrew from study prematurely. Results of the preplanned interim analysis (n=15 in each group) of the primary endpoint showed that futility criteria had been met, and the trial was stopped (the mean rate of change [slope analysis] of UMSARS I score was 0·62 points [SD 0·85] per month in the rifampicin group vs 0·47 points [0·48] per month in the placebo group; futility p=0·032; efficacy p=0·76). At the time of study termination, 49 participants in the rifampicin group and 50 in the placebo group had follow-up data and were included in the final analysis. The primary endpoint was 0·5 points (SD 0·7) per month for rifampicin and 0·5 points (0·5) per month for placebo (difference 0·0, 95% CI −0·24 to 0·24; p=0·82). Three (6%) of 50 participants in the rifampicin group and 12 (24%) of 50 in the placebo group had one or more serious adverse events; none was thought to be related to treatment.
Our results show that rifampicin does not slow or halt progression of multiple system atrophy. Despite the negative result, the trial does provide information that could be useful in the design of future studies assessing potential disease modifying therapies in patients with multiple system atrophy.
National Institutes of Health, Mayo Clinic Center for Translational Science Activities, and Mayo Funds.
Journal Article
Poly (ADP-Ribose) and α–synuclein extracellular vesicles in patients with Parkinson disease: A possible biomarker of disease severity
by
Savica, Rodolfo
,
Mielke, Michelle M.
,
Kim, Yohan
in
Adenosine Diphosphate
,
alpha-Synuclein
,
Alzheimer's disease
2022
Despite multiple attempts, no surrogate biomarker of Parkinson disease (PD) has been definitively identified. Alternatively, identifying a non-invasive biomarker is crucial to understanding the natural history, severity, and progression of PD and to guide future therapeutic trials. Recent work highlighted alpha synuclein-containing extracellular vesicles and Poly (ADP-ribose) polymerase (PARP-1) activity as drivers of PD pathogenesis and putative PD biomarkers. This exploratory study evaluated the role of alpha-synuclein-positive extracellular vesicles and PARP-1 activity in the plasma of PD patients as non-invasive markers of the disease's severity and progression.
We collected plasma of 57 PD patients (discovery cohort 20, replication cohort 37) and compared it with 20 unaffected individuals, 20 individuals with clinically diagnosed Alzheimer's disease, and 20 individuals with dementia with Lewy bodies. We analyzed alpha-synuclein-positive extracellular vesicles from platelet-free plasma by nanoscale flow cytometry and blood concentrations of poly ADP-ribose using sandwich ELISA kits.
Median concentration of α-synuclein extracellular vesicles was significantly higher in PD patients compared to the other groups (Kruskal-Wallis, p < .0001). In the discovery cohort, patients with higher α-synuclein extracellular vesicles had a higher Unified Parkinson Disease Rating Scale score (UPDRS III median = 22 vs. 5, p = 0.045). Seven out of 20 patients (35%) showed detectable PAR levels, with positive patients showing significantly higher levels of α-synuclein extracellular vesicles. In the replication cohort, we did not observe a significant difference in the PAR-positive cases in relationship with UPDRS III.
Non-invasive determination of α-synuclein-positive extracellular vesicles may provide a potential non-invasive marker of PD disease severity, and longitudinal studies are needed to evaluate the role of α-synuclein-positive extracellular vesicles as a marker of disease progression.
Journal Article
A Prospective, 1-Year Follow-up Study of Postural Tachycardia Syndrome
by
Sandroni, Paola
,
Fischer, Philip R.
,
Opfer-Gehrking, Tonette L.
in
Adrenergic alpha-1 Receptor Agonists - therapeutic use
,
Adrenergic beta-1 Receptor Antagonists - therapeutic use
,
Adult
2012
To prospectively evaluate patients who met standard criteria for postural tachycardia syndrome (POTS), at baseline and 1-year follow-up, using standard clinical and laboratory methods to assess autonomic function.
Fifty-eight patients met the study criteria (orthostatic symptoms and a heart rate increment of ≥30 beats/min on head-up tilt) and completed 12 months of follow-up. All patients were enrolled and completed the study from January 16, 2006, through April 15, 2009. Patients underwent standardized autonomic testing, including head-up tilt, clinical assessment, and validated questionnaires designed to determine the severity of autonomic symptoms.
Patients were predominantly young females (n=49, 84%), with 20 patients (34%) reporting an antecedent viral infection before onset of symptoms. More than one-third (37%) no longer fulfilled tilt criteria for POTS on follow-up, although heart rate increment on head-up tilt did not differ significantly at 1 year (33.8±15.1 beats/min) compared with baseline (37.8±14.6 beats/min) for the entire cohort. Orthostatic symptoms improved in most patients. Autonomic dysfunction was mild as defined by a Composite Autonomic Severity Score of 3 or less in 55 patients (95%) at baseline and 48 patients (92%) at 1 year.
To our knowledge, this is the first prospective study of the clinical outcomes of patients with POTS. Orthostatic symptoms improved in our patients, with more than one-third of patients no longer fulfilling tilt criteria for POTS, although the overall group change in heart rate increment was modest. Our data are in keeping with a relatively favorable prognosis in most patients with POTS.
Journal Article
Loss of putative GABAergic neurons in the ventrolateral medulla in multiple system atrophy
by
Coon, Elizabeth A
,
Schmeichel, Ann M
,
Low, Phillip A
in
Atrophy
,
Blood pressure
,
Cardiovascular disease
2021
Abstract
Study Objectives
Multiple system atrophy (MSA) is associated with disturbances in cardiovascular, sleep and respiratory control. The lateral paragigantocellular nucleus (LPGi) in the ventrolateral medulla (VLM) contains GABAergic neurons that participate in control of rapid eye movement (REM) sleep and cardiovagal responses. We sought to determine whether there was loss of putative GABAergic neurons in the LPGi and adjacent regions in MSA.
Methods
Sections of the medulla were processed for GAD65/67 immunoreactivity in eight subjects with clinical and neuropathological diagnosis of MSA and in six control subjects. These putative GABAergic LPGi neurons were mapped based on their relationship to adjacent monoaminergic VLM groups.
Results
There were markedly decreased numbers of GAD-immunoreactive neurons in the LPGi and adjacent VLM regions in MSA.
Conclusions
There is loss of GABAergic neurons in the VLM, including the LPGi in patients with MSA. Whereas these findings provide a possible mechanistic substrate, given the few cases included, further studies are necessary to determine whether they contribute to REM sleep-related cardiovagal and possibly respiratory dysregulation in MSA.
Journal Article
475 Impact of secretome derived from stool samples of patients with multiple system atrophy in alpha-synuclein oligomerization
by
Singer, Wolfgang
,
Bland, Michelle
,
Walther-António, Marina R. S.
in
Aging
,
Atrophy
,
Biosensors
2025
Objectives/Goals: This study investigates the contribution of the stool secretome (the soluble factors secreted by microbes into extracellular space) to in vitro α-synuclein (αSyn) oligomerization using stool cultures from patients with multiple system atrophy (MSA), a rare neurodegenerative disease hallmarked by pathologic αSyn aggregates. Methods/Study Population: Stool samples from MSA patients (n = 20), household controls (n = 20), and healthy controls (n = 20) will be cultured using an adapted dilution-to-extinction approach. The goal is to reduce microbial complexity progressively to produce random secretome combinations that may affect αSyn oligomerization differentially. The original inoculant and dilutions will be cultured anaerobically to collect conditioned media (CM) enriched with microbial secretomes. CM will be used to expose a fluorescence resonance energy transfer (FRET) biosensor assay and a Gaussia luciferase protein complementation assay – both modified to quantify αSyn-αSyn interaction indicating oligomerization. Any CM-altering αSyn oligomerization will undergo multiomic characterization to identify potential causative agent(s). Results/Anticipated Results: Specific microbe-produced molecules from the literature are anticipated to modulate αSyn oligomerization, identified by targeted, reductionist studies that selected and tested separately single microbial factors on αSyn aggregation in vitro and in vivo. From these studies, lipopolysaccharide and bacterial amyloid protein are expected to increase αSyn oligomerization, while short-chain fatty acids, such as butyrate, are expected to interfere with and decrease oligomerization. As a complementary systemic approach, this study’s agnostic methods involving MSA stool culture combined with the proposed dilution-to-extinction method are expected to identify additional MSA stool secretome components modulating αSyn oligomerization that might otherwise be missed in earlier reductionist approaches. Discussion/Significance of Impact: Completion of this reverse-translational work will aid in discovering MSA stool secretome components modulating αSyn oligomerization. Identification of specific factors contributing to pathologic αSyn behavior might set the stage for patient screenings for identified stool markers and could lead to microbiome-based interventions for MSA.
Journal Article
Ganglionic Antibody Level as a Predictor of Severity of Autonomic Failure
by
Sandroni, Paola
,
Benarroch, Eduardo E.
,
Cutsforth-Gregory, Jeremy K.
in
Acetylcholine receptors (nicotinic)
,
Autoantibodies
,
Autoimmune diseases
2018
To assess antibody level as a test of autonomic failure (AF) associated with ganglionic nicotinic acetylcholine receptor antibody (AChR-Ab) autoimmunity.
We searched the Mayo Clinic laboratory database of 926 ganglionic AChR-Ab–seropositive patients seen at our institution between October 1, 1997, and April 1, 2015, for initial level of 0.05 nmol/L or higher and contemporaneous autonomic reflex screen (standardized evaluation of adrenergic, cardiovagal, and sudomotor functions) from which Composite Autonomic Scoring Scale (CASS) scores could be calculated.
Of 289 patients who met inclusion criteria, 163 (56.4%) were women, median age was 54 years (range, 10-87 years), median antibody level was 0.11 nmol/L (range, 0.05-22.10 nmol/L), and median CASS total score was 2.0 (range, 0-10). Using receiver operating characteristic curve analysis, a level above 0.40 nmol/L predicted severe AF (CASS score, ≥7) with 92% specificity and 56% sensitivity. For at least moderate AF (CASS score ≥4 and anhidrosis ≥25%), a level of at least 0.20 nmol/L had 80% specificity and 59% sensitivity. Levels below 0.20 nmol/L were not predictive of the presence or absence of AF. For predicting orthostatic hypotension, ganglionic AChR-Ab level had excellent specificity above 0.4 nmol/L but lacked sensitivity. Autoantibodies to additional targets were present in 61 patients (21.1%).
Ganglionic AChR-Ab level of at least 0.40 nmol/L is a moderately sensitive and highly specific marker for severe AF, as is a level of at least 0.20 nmol/L for moderate AF if CASS score is coupled with anhidrosis of 25% or more, among patients with suspected ganglionic AChR-Ab autoimmune autonomic ganglionopathy. Antibody levels of less than 0.20 nmol/L have little clinical importance in the absence of clinical AF.
Journal Article