Phenoconversion in pure autonomic failure: a multicentre prospective longitudinal cohort study.

We aimed to describe the clinical features of patients with pure autonomic failure (PAF) preceding phenoconversion that could be useful as predictive markers for advancing α-synuclein-associated neurodegeneration of the brain. Patients diagnosed with PAF were evaluated at eight centres (seven US-based and one European) and enrolled in a longitudinal observational cohort study (NCT01799915). Subjects underwent detailed assessments of motor, sleep, olfactory, cognitive and autonomic function and were followed prospectively to determine whether they developed parkinsonism or dementia for up to 10 years. We identified incident cases of Parkinson's disease (PD), dementia with Lewy bodies (DLB) or multiple system atrophy (MSA) and computed hazard ratios for phenoconversion as functions of clinical features. A total of 209 participants with PAF with a median disease duration of 6 years (IQR: 3-10) were enrolled. Of those, 149 provided follow-up information at an office or telemedicine visit. After a mean follow-up duration of 3 years, 48 (33%) participants phenoconverted (42% to PD, 35% to DLB and 23% to MSA). Faster phenoconversion from study enrolment to any diagnosis was associated with urinary and sexual dysfunction [hazard ratio (HR) 5.9, 95% confidence interval (CI): 1.6-22 and HR: 3.6, 95% CI: 1.1-12] followed by subtle motor signs (HR: 2.7, 95% CI: 1.2-6), trouble swallowing (HR 2.5, 95% CI: 1.4-4.5) and changes in speech (HR:2.4, 95% CI:1.1-4.8) at enrolment. Subjects reporting deterioration of handwriting were more likely to phenoconvert to PD (HR: 2.6, 95% CI: 1.1-5.9) and those reporting difficulty handling utensils were more likely to phenoconvert to DLB (HR: 6.8, 95% CI: 1.2-38). Patients with a younger age of PAF onset (HR: 11, 95% CI: 2.6-46), preserved olfaction (HR: 8.7, 95% CI: 1.7-45), anhidrosis (HR: 1.8, 95% CI: 1-3.1, P = 0.042) and severe urinary problems (HR 1.6, 95% CI: 1-2.5, P = 0.033) were more likely to phenoconvert to MSA. The best autonomic predictor of PD was a blunted heart rate increase during the tilt-table test (HR: 6.1, 95% CI: 1.4-26). Patients with PAF have an estimated 12% (95% CI: 9-15%) per year annual risk following study entry of phenoconverting to a manifest CNS synucleinopathy.

Nocturnal Pulse Event Frequency Is Reduced in Multiple System Atrophy.

Risk of sudden death in multiple system atrophy (MSA) is greatest during sleep with unknown mechanisms. We compared nocturnal pulse event frequency in 46 MSA patients and age-/sex-matched controls undergoing overnight pulse oximetry. Nocturnal oxyhemoglobin desaturation indices and pulse event indices (PEIs) were recorded, and relationships between pulse oximetry variables and survival were analyzed. MSA patients had lower PEI (3.1 ± 5.3 vs. 12.8 ± 10.8, p < 0.001) despite greater hypoxic burden and similar frequency of respiratory events. Nocturnal pulse events were not associated with severity of daytime autonomic failure. Two MSA patients had suspected sudden death, both with severely reduced PEI. MSA patients have fewer nocturnal pulse events compared with controls, despite similar respiratory event frequency, suggesting abnormal cardiac responses to sleep-disordered breathing. Whether this contributes to sudden death in MSA requires further study. ANN NEUROL 2023;93:205-212.

Autonomic impairment in primary lateral sclerosis.

PURPOSE: Prior studies reported evidence of autonomic involvement in motor neuron disease and suggested more severe dysfunction in upper motor neuron predominant syndromes. Hence, we sought to characterize autonomic impairment in primary lateral sclerosis. METHODS: Neurological evaluations, thermoregulatory sweat tests, and autonomic reflex screens were analyzed retrospectively in 34 primary lateral sclerosis patients (28 definite and 6 probable). Patients with other potential causes of autonomic failure and patients with autonomic testing results compromised by artifact were excluded. RESULTS: A total of 17 patients reported autonomic symptoms. Orthostatic lightheadedness was most frequent (8 patients), followed by bladder (7), bowel (5), and erectile dysfunction (3). The autonomic reflex screens of 33 patients were reviewed; 20 patients had abnormal studies. The thermoregulatory sweat tests of 19 patients were reviewed; 11 patients had abnormal studies. Composite Autonomic Severity Score was calculated for 33 patients and found abnormal in 20/33 patients (60.6%): 15/20 patients (75%) had mild impairment, and 5/20 patients (25%) had moderate impairment. The frequencies of testing abnormalities were: sudomotor 18/20 (90%), cardiovagal 9/20 (45%), and adrenergic 6/20 (30%). Sweat loss pattern analysis showed global, regional, and mixed patterns to be more common than length-dependent and distal patterns. CONCLUSION: We found evidence of frequent autonomic dysfunction in primary lateral sclerosis, which is generally of modest severity akin to prior reports for amyotrophic lateral sclerosis, but more commonly in a pattern consistent with preganglionic/ganglionic localization. This suggests that primary lateral sclerosis, as with amyotrophic lateral sclerosis, is a multisystem disease that affects the autonomic nervous system.

Autonomic dysfunction following COVID-19 infection: an early experience.

PURPOSE: Post-COVID-19 syndrome is a poorly understood aspect of the current pandemic, with clinical features that overlap with symptoms of autonomic/small fiber dysfunction. An early systematic analysis of autonomic dysfunction following COVID-19 is lacking and may provide initial insights into the spectrum of this condition. METHODS: We conducted a retrospective review of all patients with confirmed history of COVID-19 infection referred for autonomic testing for symptoms concerning for para-/postinfectious autonomic dysfunction at Mayo Clinic Rochester or Jacksonville between March 2020 and January 2021. RESULTS: We identified 27 patients fulfilling the search criteria. Symptoms developed between 0 and 122 days following the acute infection and included lightheadedness (93%), orthostatic headache (22%), syncope (11%), hyperhidrosis (11%), and burning pain (11%). Sudomotor function was abnormal in 36%, cardiovagal function in 27%, and cardiovascular adrenergic function in 7%. The most common clinical scenario was orthostatic symptoms without tachycardia or hypotension (41%); 22% of patients fulfilled the criteria for postural tachycardia syndrome (POTS), and 11% had borderline findings to support orthostatic intolerance. One patient each was diagnosed with autoimmune autonomic ganglionopathy, inappropriate sinus tachycardia, vasodepressor syncope, cough/vasovagal syncope, exacerbation of preexisting orthostatic hypotension, exacerbation of sensory and autonomic neuropathy, and exacerbation of small fiber neuropathy. CONCLUSION: Abnormalities on autonomic testing were seen in the majority of patients but were mild in most cases. The most common finding was orthostatic intolerance, often without objective hemodynamic abnormalities on testing. Unmasking/exacerbation of preexisting conditions was seen. The temporal association between infection and autonomic symptoms implies a causal relationship, which however cannot be proven by this study.

Submentalis Rapid Eye Movement Sleep Muscle Activity: A Potential Biomarker for Synucleinopathy.

Accurate antemortem diagnosis of parkinsonism is primarily based on clinical evaluation with limited biomarkers. We evaluated the diagnostic utility of quantitative rapid eye movement (REM) sleep without atonia analysis in the submentalis and anterior tibialis muscles in parkinsonian patients (53 synucleinopathy, 24 tauopathy). Receiver operating characteristic curves determined REM sleep without atonia cutoffs distinguishing synucleinopathies from tauopathies. Elevated submentalis muscle activity was highly sensitive (70-77%) and specific (95-100%) in distinguishing synucleinopathy from tauopathy. In contrast, anterior tibialis synucleinopathy discrimination was poor. Our results suggest that elevated submentalis REM sleep without atonia appears to be a potentially useful biomarker for presumed synucleinopathy etiologies in parkinsonism. ANN NEUROL 2019;86:969-974.

Lower Vitamin B12 Level at Multiple System Atrophy Diagnosis Is Associated With Shorter Survival.

BACKGROUND: Multiple system atrophy (MSA) is a neurodegenerative disorder from α-synuclein aggregation. in vitro studies suggest vitamin B12 may interrupt α-synuclein-mediated neurodegeneration. The objective of this study was to determine whether serum vitamin B12 level at MSA diagnosis is associated with survival. METHODS: One hundred eighty-two MSA patients evaluated at Mayo Clinic with vitamin B12 testing were studied. We determined the risk of death in relationship to serum vitamin B12 levels at MSA diagnosis, adjusting for predictors of poor survival. RESULTS: Predictors of shorter survival included vitamin B12 < 367 ng/L (HR, 1.8; 95% CI, 1.3-2.7), falls within 3 years of MSA diagnosis (HR, 1.6; 95% CI, 1.1-2.3), bladder symptoms (HR, 1.6; 95% CI, 1.0-2.6), urinary catheter requirement (HR, 1.7; 95% CI, 1.0-2.8), male sex (HR, 1.4; 95% CI, 1.0-2.0), and MSA-P subtype (HR, 1.5; 95% CI, 1.0-2.0). CONCLUSIONS: Low vitamin B12 levels are associated with shorter survival in MSA. Additional studies to explore this observation and assess the potential role of vitamin B12 as a modifiable survival factor are needed. © 2020 International Parkinson and Movement Disorder Society.

Autonomic Dysfunction in the Synucleinopathies.

Autonomic dysfunction is a characteristic feature in the synucleinopathies. Differences in cellular deposition and neuronal populations affected by α-synuclein aggregation influence the manifestations and severity of autonomic failure in the different synucleinopathy disorders. The Lewy body disorders (Parkinson's disease, dementia with Lewy bodies, and pure autonomic failure) have predominantly peripheral involvement, whereas multiple system atrophy chiefly manifests as central autonomic failure. Clinical and laboratory features may be useful in distinguishing the different synucleinopathies based on the pattern and severity of autonomic failure. Treatment recommendations are aimed at the underlying pathophysiology and utilize non-pharmacologic and pharmacologic approaches. This review will focus on pathophysiology, clinical manifestations, and management recommendations for autonomic failure including neurogenic orthostatic hypotension, thermoregulatory dysfunction, genitourinary dysfunction, and gastrointestinal dysfunction in the synucleinopathies.

Neuropathology of autonomic dysfunction in synucleinopathies.

The synucleinopathies-Parkinson's disease, dementia with Lewy bodies, multiple system atrophy, and pure autonomic failure-result from distinct patterns of abnormal α-synuclein aggregation throughout the nervous system. Autonomic dysfunction in these disorders results from variable involvement of the central and peripheral autonomic networks. The major pathologic hallmark of Parkinson's disease and dementia with Lewy bodies is Lewy bodies and Lewy neurites; of multiple system atrophy, oligodendroglial cytoplasmic inclusions; and of pure autonomic failure, peripheral neuronal cytoplasmic inclusions. Clinical manifestations include orthostatic hypotension, thermoregulatory dysfunction, gastrointestinal dysmotility, and urogenital dysfunction with neurogenic bladder and sexual dysfunction. Strong evidence supports isolated idiopathic rapid eye movement sleep disorder as a significant risk factor for the eventual development of synucleinopathies with autonomic and/or motor involvement. In contrast, some neurologically normal elderly individuals have Lewy-related pathology. Future work may reveal protective or vulnerability factors that allow some patients to harbor Lewy pathology without overt autonomic dysfunction. © 2018 International Parkinson and Movement Disorder Society.

Anhidrosis in multiple system atrophy involves pre- and postganglionic sudomotor dysfunction.

BACKGROUND: The objective of this study was to characterize the degree, pattern, lesion site, and temporal evolution of sudomotor dysfunction in multiple system atrophy (MSA) and to evaluate differences by parkinsonian (MSA-parkinsonism) and cerebellar (MSA-cerebellar) subtypes. METHODS: All cases of MSA evaluated at Mayo Clinic Rochester between 2005 and 2010 with postganglionic sudomotor testing and thermoregulatory sweat test were reviewed. Pattern and lesion site (preganglionic, postganglionic, or mixed) were determined based on thermoregulatory sweat test and postganglionic sudomotor testing. RESULTS: The majority of the 232 patients were MSA-parkinsonism (145, 63%). Initial postganglionic sudomotor testing was abnormal in 59%, whereas thermoregulatory sweat test was abnormal in 95% of all patients. MSA-parkinsonism patients were more likely to have an abnormal thermoregulatory sweat test compared with MSA-cerebellar (98% versus 90%, P = 0.006) and had a higher mean percentage of anhidrosis (57%) compared with MSA-cerebellar (48%; P = 0.033). Common anhidrosis patterns were regional (38%) and global (35%). The site of the lesion was preganglionic in 47% and mixed (preganglionic and postganglionic) in 41%. The increase in anhidrosis per year was 6.2% based on 70 repeat thermoregulatory sweat tests performed on 29 patients. The frequency of postganglionic sudomotor abnormalities increased over time. CONCLUSIONS: Our findings suggest: (1) sudomotor dysfunction is almost invariably present in MSA and even more common and severe in MSA-parkinsonism than MSA-cerebellar; (2) a preganglionic pattern of sweat loss is common in MSA; however, pre- and postganglionic abnormalities may coexist; and (3) the increasing frequency of postganglionic sudomotor dysfunction over time suggests involvement of postganglionic fibers or sweat glands later in the disease course. © 2016 International Parkinson and Movement Disorder Society.

Medullary neuronal loss is not associated with α-synuclein burden in multiple system atrophy.

BACKGROUND: Accumulation of α-synuclein in multiple system atrophy (MSA) affects medullary autonomic and respiratory control areas, including the rostral ventrolateral medulla and raphe nuclei. Relative neuronal vulnerability and its relationship to α-synuclein accumulation in these areas are unknown. The aim of this study was to determine the extent of loss of adrenergic neurons in the rostral ventrolateral medulla and serotonergic neurons in the ventrolateral medulla and raphe nuclei and its relationship with α-synuclein accumulation. METHODS: Medullary sections from 7 MSA and 6 control subjects were processed for tyrosine hydroxylase, tryptophan hydroxylase, and α-synuclein immunoreactivity. Neuronal counts were performed stereologically, whereas α-synuclein burden in oligodendrocytes and neurons was quantified using object detection density (area/mm2). RESULTS: All MSA cases had orthostatic hypotension; 5 had laryngeal stridor. There was marked neuronal loss in the rostral ventrolateral medulla and medullary raphe in all cases. Most severely affected were tyrosine hydroxylase ventrolateral medulla (C1) neurons (83% reduction), followed by tryptophan hydroxylase neurons in the ventrolateral medulla (70%), raphe obscurus (56%), pallidus (57%), and magnus (47%). α-Synuclein accumulation occurred predominantly as glial cytoplasmic inclusions with rare α-synuclein accumulation occurring within the remaining neurons. Density of α-synuclein did not correlate with neuronal loss in any of the areas analyzed, and there was no correlation between α-synuclein density and disease duration for any regions of interest. CONCLUSIONS: These findings indicate that in MSA adrenergic neurons are more susceptible than serotonergic neurons in the medulla. Further, loss of medullary monoaminergic neurons may progress independently from α-synuclein accumulation in MSA. © 2016 International Parkinson and Movement Disorder Society.

Expanding the spectrum of neuronal pathology in multiple system atrophy.

Multiple system atrophy is a sporadic alpha-synucleinopathy that typically affects patients in their sixth decade of life and beyond. The defining clinical features of the disease include progressive autonomic failure, parkinsonism, and cerebellar ataxia leading to significant disability. Pathologically, multiple system atrophy is characterized by glial cytoplasmic inclusions containing filamentous alpha-synuclein. Neuronal inclusions also have been reported but remain less well defined. This study aimed to further define the spectrum of neuronal pathology in 35 patients with multiple system atrophy (20 male, 15 female; mean age at death 64.7 years; median disease duration 6.5 years, range 2.2 to 15.6 years). The morphologic type, topography, and frequencies of neuronal inclusions, including globular cytoplasmic (Lewy body-like) neuronal inclusions, were determined across a wide spectrum of brain regions. A correlation matrix of pathologic severity also was calculated between distinct anatomic regions of involvement (striatum, substantia nigra, olivary and pontine nuclei, hippocampus, forebrain and thalamus, anterior cingulate and neocortex, and white matter of cerebrum, cerebellum, and corpus callosum). The major finding was the identification of widespread neuronal inclusions in the majority of patients, not only in typical disease-associated regions (striatum, substantia nigra), but also within anterior cingulate cortex, amygdala, entorhinal cortex, basal forebrain and hypothalamus. Neuronal inclusion pathology appeared to follow a hierarchy of region-specific susceptibility, independent of the clinical phenotype, and the severity of pathology was duration-dependent. Neuronal inclusions also were identified in regions not previously implicated in the disease, such as within cerebellar roof nuclei. Lewy body-like inclusions in multiple system atrophy followed the stepwise anatomic progression of Lewy body-spectrum disease inclusion pathology in 25.7% of patients with multiple system atrophy, including a patient with visual hallucinations. Further, the presence of Lewy body-like inclusions in neocortex, but not hippocampal alpha-synuclein pathology, was associated with cognitive impairment (P = 0.002). However, several cases had the presence of isolated Lewy body-like inclusions at atypical sites (e.g. thalamus, deep cerebellar nuclei) that are not typical for Lewy body-spectrum disease. Finally, interregional correlations (rho ≥ 0.6) in pathologic glial and neuronal lesion burden suggest shared mechanisms of disease progression between both discrete anatomic regions (e.g. basal forebrain and hippocampus) and cell types (neuronal and glial inclusions in frontal cortex and white matter, respectively). These findings suggest that in addition to glial inclusions, neuronal pathology plays an important role in the developmental and progression of multiple system atrophy.

Clinical features and autonomic testing predict survival in multiple system atrophy.

Multiple system atrophy is characterized by autonomic failure along with motor symptoms of parkinsonism and/or cerebellar ataxia. There are differing reports on the influence of certain clinical features, including motor subtype (multiple system atrophy-parkinsonism versus multiple system atrophy-cerebellar ataxia), age of onset, gender, and early autonomic symptoms, on the survival in patients with multiple system atrophy. We sought to evaluate overall survival and predictors of survival in a large cohort of patients with multiple system atrophy seen at a single referral centre where objective autonomic testing is routinely performed for this indication. All cases of multiple system atrophy evaluated at Mayo Clinic, Rochester and assessed with an autonomic reflex screen between January 1998 and December 2012 were retrospectively reviewed. A total of 685 patients were identified; 594 met criteria for probable multiple system atrophy, and 91 for possible multiple system atrophy. Multiple system atrophy-parkinsonism was the predominant subtype in 430 patients (63%). Average age of onset was earlier in multiple system atrophy-cerebellar ataxia (58.4 years) compared to multiple system atrophy-parkinsonism (62.3 years; P < 0.001). Median disease duration from symptom onset to death was 7.51 years (95% confidence interval 7.18-7.78) while time from diagnosis to death was 3.33 years (95% confidence interval 2.92-3.59). There was no difference in survival between motor subtypes of multiple system atrophy (P = 0.232). An initial motor symptom was most common (61%) followed by autonomic onset (28%) and combined motor and autonomic symptoms (11%). The initial onset of either motor or autonomic symptoms did not influence length of survival. However, a number of clinical and autonomic laboratory features predicted unfavourable survival in a univariate analysis. A multivariate model retained the following unfavourable predictors of survival: (i) falls within 3 years of onset (hazard ratio 2.31, P < 0.0001); (ii) bladder symptoms (hazard ratio 1.96, P < 0.0001); (iii) urinary catheterization within 3 years of symptom onset (hazard ratio 1.67, P < 0.003); (iv) orthostatic intolerance within 1 year of symptom onset (hazard ratio 1.28, P < 0.014); (v) older age of onset (hazard ratio 1.02, P = 0.001); and (vi) degree of autonomic failure as measured by a validated composite autonomic severity score (hazard ratio 1.07, P < 0.0023). We conclude that carefully selected clinical features can be used to predict survival in patients with multiple system atrophy. Autonomic testing adds an additional, independent predictor of survival, demonstrating its value not only in the diagnosis of multiple system atrophy but also as prognostic marker.

Prevalence of REM sleep behavior disorder in multiple system atrophy: a multicenter study and meta-analysis.

OBJECTIVE: Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia frequently affecting patients with synucleinopathies, but its exact prevalence in multiple system atrophy (MSA) is unclear. Whether questionnaires alone are sufficient to diagnose RBD is also unknown. METHODS: We performed a cross-sectional study of patients with probable MSA from six academic centers in the US and Europe. RBD was ascertained clinically and with polysomnography; we also performed a meta-analysis according to PRISMA guidelines for studies published before September 2014 that reported the prevalence of RBD in MSA. A random-effects model was constructed using weighted prevalence proportions. Only articles in English were included. Studies were classified into those that ascertained the presence of RBD in MSA clinically and with polysomnography. Case reports or case series (≤ 5 patients) were not included. RESULTS: Forty-two patients completed questionnaires and underwent polysomnography. Of those, 32 (76.1%) had clinically suspected RBD and 34 (81%) had polysomnography-confirmed RBD. Two patients reported no symptoms of RBD but had polysomnography-confirmed RBD. The primary search strategy yielded 374 articles of which 12 met the inclusion criteria. The summary prevalence of clinically suspected RBD was 73% (95 % CI, 62-84%) in a combined sample of 324 MSA patients. The summary prevalence of polysomnography-confirmed RBD was 88 % (95% CI, 79-94%) in a combined sample of 217 MSA patients. INTERPRETATION: Polysomnography-confirmed RBD is present in up to 88% of patients with MSA. RBD was present in some patients that reported no symptoms. More than half of MSA patients report symptoms of RBD before the onset of motor deficits.

The Auxiliary to the American Academy of Neurology.

The American Academy of Neurology (AAN) was founded in 1948, and the Women's Auxiliary to the AAN was founded shortly thereafter. We reviewed historical archives of the AAN and Women's Auxiliary and interviewed past Auxiliary leaders to understand the perception and roles of neurologists' spouses. The Women's Auxiliary to the AAN was originally formed for the wives of neurologist Academy members with the intention of facilitating social and intragroup relationships. The first leaders and members of the organization included some of the spouses of the original Academy founders. With the original scope to provide socialization while the men were at meetings, the male neurologists initially planned much of the Auxiliary's activities. Over time, the Auxiliary's activities shifted and became women-led; engagement in community outreach grew, subcommittees expanded, and the group engaged in supporting the AAN in achieving its goals of improving neurology education and research. The change paralleled the women's movement with educational topics during the Auxiliary's meetings evolving from topics on homemaking to business and understanding neurologic diseases. The Auxiliary was intertwined with the Academy and initiated the S. Weir Mitchell Award and the Founders Award of the AAN in 1955 and 1994 to encourage basic and clinical research in neurology, respectively. In 1982, the Auxiliary requested increased involvement in the scientific programs at the annual meetings. Reflecting societal change, the name was changed to the "Auxiliary to the AAN" in the 1970s, and in the mid-1990s to the "Alliance to the AAN" to accommodate the increasing number of male partners of neurologists. Based on interviews, the Auxiliary provided engagement, empowerment, and connection between women. The Auxiliary's activities tapered in the late 1990s, in part due to changes in women's occupations, and to the rise of women's membership and leadership within the Academy.