Identifying New Subtypes of Multiple System Atrophy Using Cluster Analysis

Background

Multiple system atrophy (MSA) is a disease with diverse symptoms and the commonly used classifications, MSA-P and MSA-C, do not cover all the different symptoms seen in MSA patients. Additionally, these classifications do not provide information about how the disease progresses over time or the expected outcome for patients.

Objective

To explore clinical subtypes of MSA with a natural disease course through a data-driven approach to assist in the diagnosis and treatment of MSA.

Methods

We followed 122 cases of MSA collected from 3 hospitals for 3 years. Demographic characteristics, age of onset, clinical signs, scale assessment scores, and auxiliary examination were collected. Age at onset; time from onset to assisted ambulation; and UMSARS I, II, and IV, COMPASS-31, ICARS, and UPDRS III scores were selected as clustering elements. K-means, partitioning around medoids, and self-organizing maps were used to analyze the clusters.

Results

The results of all three clustering methods supported the classification of three MSA subtypes: The aggressive progression subtype (MSA-AP), characterized by mid-to-late onset, rapid progression and severe clinical symptoms; the typical subtype (MSA-T), characterized by mid-to-late onset, moderate progression and moderate severity of clinical symptoms; and the early-onset slow progression subtype (MSA-ESP), characterized by early-to-mid onset, slow progression and mild clinical symptoms.

Conclusions

We divided MSA into three subtypes and summarized the characteristics of each subtype. According to the clustering results, MSA patients were divided into three completely different types according to the severity of symptoms, the speed of disease progression, and the age of onset.

Chronotropic Incompetence in Parkinson's Disease: A Possible Marker of Severe Disease Phenotype?

Autonomic dysfunction is a prevalent feature of Parkinson's disease (PD), mediated by disease involvement of the autonomic nervous system. Chronotropic incompetence (CI) refers to inadequate increase of heart rate in response to elevated metabolic demand, partly dependent on postganglionic sympathetic tone. In a retrospective study, PD patients with/without CI were identified. We show that PD with CI was associated with a higher levodopa equivalent daily dose and Hoehn and Yahr stage, 5±2 years after motor onset. Our data support a putative role of CI as a clinical marker of a more severe disease phenotype, possibly reflecting more widespread alpha-synuclein pathology.

Bridging the gap in BASCULE syndrome: A retrospective case series of a recently described clinical entity

BACKGROUND

Bier anemic spots, cyanosis with urticaria-like eruption (BASCULE) syndrome is a recently described entity with episodic urticarial lesions and white anemic halos on a background of erythrocyanosis, commonly affecting the lower extremities. Possible association with autonomic dysfunction remains poorly understood. Existing publications are limited, but the condition is suggested as highly underrecognized.

OBJECTIVE

To further characterize clinical and epidemiologic data for BASCULE syndrome.

METHODS

We performed an IRB-approved retrospective chart review on patients with BASCULE syndrome evaluated at Mayo Clinic from April 2021 to November 2022.

RESULTS

A total of 17 patients were identified (13 female, 4 male). Median age of onset was 12 years (range 9-17). Lower extremities were involved in all patients (17). Most patients were symptomatic with pruritus (8) or burning pain (8); three were asymptomatic. Triggers were standing (11), hot showers or hot environments (7), or no clear trigger (4). Autonomic dysfunction was present in 10 patients. Treatment responses were observed from propranolol (3) and high-dose cetirizine (1).

CONCLUSION

Novel epidemiologic data from 17 pediatric and young adult patients with BASCULE syndrome further supports an association with autonomic dysfunction and suggests a higher prevalence than previously acknowledged.

The Effects of Autonomic Dysfunction on Functional Outcomes in Patients with Acute Stroke

Autonomic dysfunction is a common complication of acute stroke, which impairs functional outcomes and increases mortality. There is a lack of well-established knowledge regarding the influence of autonomic dysfunction in patients with acute stroke. This study aims to investigate the impact of the severity of autonomic dysfunction on functional outcomes in patients with acute stroke. A retrospective analysis was conducted at a single center, involving 22 patients diagnosed with acute stroke. The severity of autonomic dysfunction was evaluated based on the Composite Autonomic Scoring Scale (CASS). The modified Barthel Index, Berg Balance Scale, Functional Ambulatory Category, and modified Rankin Scale were designated as functional outcome measures. The impact of the severity of autonomic dysfunction on functional outcomes was analyzed using one-way analysis of covariance (ANCOVA). A statistically significant difference was observed between the initial and follow-up functional outcomes based on the severity of autonomic dysfunction. This study presents evidence that the severity of autonomic dysfunction influences functional prognosis in patients with acute stroke. The findings will serve as additional considerations for the rehabilitation of patients with acute stroke.

Cardiac Autonomic Function and Functional Capacity in Post-COVID-19 Individuals with Systemic Arterial Hypertension

Individuals diagnosed with systemic arterial hypertension (SAH) are considered risk groups for COVID-19 severity. This study assessed differences in cardiac autonomic function (CAF) and functional capacity (FC) in SAH individuals without COVID-19 infection compared to SAH individuals post-COVID-19. Participants comprised 40 SAH individuals aged 31 to 80 years old, grouped as SAH with COVID-19 (G1; n = 21) and SAH without COVID-19 (G2; n = 19). CAF was assessed via heart rate variability (HRV), measuring R-R intervals during a 10-min supine period. Four HRV indices were analyzed through symbolic analysis: 0V%, 1V%, 2LV%, and 2UV%. FC assessment was performed by a 6-min walk test (6MWT). G1 and G2 showed no significant differences in terms of age, anthropometric parameters, clinical presentation, and medication use. G2 exhibited superior 6MWT performance, covering more distance (522 ± 78 vs. 465 ± 59 m, p < 0.05). Specifically, G2 demonstrated a moderate positive correlation between 6MWT and the 2LV% index (r = 0.58; p < 0.05). Shorter walking distances were observed during 6MWT in SAH individuals post-COVID-19. However, the study did not find impaired cardiac autonomic function in SAH individuals post-COVID-19 compared to those without. This suggests that while COVID-19 impacted FC, CAF remained relatively stable in this population.

Anti-SOX1 antibodies-positive paraneoplastic neurological syndromes caused by thyroid carcinoma: A case report

RATIONALE

Paraneoplastic neurological syndromes (PNSs) are a group of neurological diseases caused by distant immune effects of malignant tumors, which often occur in patients with small cell lung cancer but are not prone to occur in patients with thyroid cancer. Anti-Sry-like high mobility group box (SOX)1 antibodies (abs)-associated PNSs caused by thyroid cancer are clinically rarer.

PATIENT CONCERNS

A 57-year-old Chinese male patient presented with autonomic neuropathy. A thyroid biopsy revealed the diagnosis of papillary thyroid microcarcinoma. The serum anti-SOX1 abs confirmed positive.

DIAGNOSES

A diagnosis of anti-SOX1 antibodies-positive PNS was made.

INTERVENTIONS

The patient received total thyroidectomy.

OUTCOMES

After total thyroidectomy, the patient's symptoms resolved quickly, and the serum anti-SOX1 abs test results was negative on re-examination.

LESSONS

Thyroid cancer can cause anti-SOX1 abs-associated PNS with only autonomic neuropathy.

Use of Valsalva Maneuver to Detect Late-Onset Delayed Orthostatic Hypotension

BACKGROUND

Standard autonomic testing includes a 10-minute head-up tilt table test to detect orthostatic hypotension. Although this test can detect delayed orthostatic hypotension (dOH) between 3 and 10 minutes of standing, it cannot detect late-onset dOH after 10 minutes of standing.

METHODS

To determine whether Valsalva maneuver responses can identify patients who would require prolonged head-up tilt table test to diagnose late-onset dOH; patients with immediate orthostatic hypotension (onset <3 minutes; n=176), early-onset dOH (onset between 3 and 10 minutes; n=68), and late-onset dOH (onset >10 minutes; n=32) were retrospectively compared with controls (n=114) with normal head-up tilt table test and composite autonomic scoring scale score of 0.

RESULTS

Changes in baseline systolic blood pressure at late phase 2 (∆SBPVM2), heart rate difference between baseline and phase 3 (∆HRVM3), and Valsalva ratio were lower and pressure recovery time (PRT) at phase 4 was longer in late-onset dOH patients than in controls. Differences in PRT and ∆HRVM3 remained significant after correcting for age. A PRT ≥2.14 s and ∆HRVM3 ≤15 bpm distinguished late-onset dOH from age- and sex-matched controls. Patients with longer PRT (relative risk ratio, 2.189 [1.579-3.036]) and lower ∆HRVM3 (relative risk ratio, 0.897 [0.847-0.951]) were more likely to have late-onset dOH. Patients with longer PRT (relative risk ratio, 1.075 [1.012-1.133]) were more likely to have early-onset than late-onset dOH.

CONCLUSIONS

Long PRT and short ∆HRVM3 can help to identify patients who require prolonged head-up tilt table test to diagnose late-onset dOH.

Evaluation of comorbid diseases in obstructive sleep apnea syndrome

OBJECTIVE

It is known that obstructive sleep apnea syndrome affects many systems due to hypoxemia and hypercarbia. We aimed to demonstrate with the utilization of well-standardized questionnaire tools and electrophysiological tests that cognitive impairment, depression, autonomic dysfunction, and metabolic syndrome may occur in association with obstructive sleep apnea syndrome.

METHODS

The electrophysiological examination protocol of autonomic nervous system functions was performed with sympathetic skin response and R-R Interval. Patients were administered Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, Montreal Cognitive Assessment, and Hamilton Depression Rating Scale by physicians in face-to-face interviews.

RESULTS

This study included 148 participants, consisting of 73 patients and 75 controls. There was a statistically significant difference between the patient group and control group with regard to sympathetic skin response, R-R Interval, post-hyperventilation R-R Interval, and R-R Interval variation (p<0.001). A statistically significant difference was observed between the patient group and control group in terms of median Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, and Montreal Cognitive Assessment scores. It was observed that the control group achieved significantly better scores than the patient group in delayed recall (p<0.001) and language (p<0.05) categories.

CONCLUSION

Obstructive sleep apnea syndrome patients should be screened for diseases, especially in the cardiovascular system, that cause serious morbidity and impair functionality such as dementia and depression. We believe that many comorbid diseases encountered in obstructive sleep apnea syndrome patients can be prevented with early diagnosis and continuous positive airway pressure treatment.

Is there a link between heart rate variability and cognitive decline? A cross-sectional study on patients with mild cognitive impairment and cognitively healthy controls

BACKGROUND

Given that, up to date, there is no effective strategy to treat dementia, a timely start of interventions in a prodromal stage such as mild cognitive impairment (MCI) is considered an important option to lower the overall societal burden. Although autonomic functions have been related to cognitive performance, both aspects have rarely been studied simultaneously in MCI.

OBJECTIVE

The aim of the present study was to investigate cardiac autonomic control in older adults with and without MCI.

METHODS

Cardiac autonomic control was assessed by means of heart rate variability (HRV) at resting state and during cognitive tasks in 22 older adults with MCI and 29 healthy controls (HCs). Resting HRV measurement was performed for 5 minutes during a sitting position. Afterwards, participants performed three PC-based tasks to probe performance in executive functions and language abilities (i.e., Stroop, N-back, and a verbal fluency task).

RESULTS

Participants with MCI showed a significant reduction of HRV in the frequency-domain (high frequency power) and nonlinear indices (SD2, D2, and DFA1) during resting state compared to HCs. Older individuals with MCI exhibited decreases in RMSSD and increases in DFA1 from resting state to Stroop and N-back tasks, reflecting strong vagal withdrawal, while this parameter remained stable in HCs.

CONCLUSION

The results support the presence of autonomic dysfunction at the early stage of cognitive impairment. Heart rate variability could help in the prediction of cognitive decline as a noninvasive biomarker or as a tool to monitor the effectiveness of therapy and prevention of neurodegenerative diseases.

Autonomic and cardiorespiratory responses to the active tilt test in individuals with Parkinson disease: cross-sectional study

BACKGROUND

The Parkinson disease (PD) is frequently associated with autonomic dysfunctions. However, data regarding the influence of PD on the autonomic responses to postural changes is limited.

OBJECTIVE

To analyze and compare the autonomic responses, evaluated through linear and non-linear methods of heart rate variability, and cardiorespiratory parameters in two groups: Parkinson disease (PDG) and control (CG), at rest and during the active tilt test.

METHODS

A total of 48 participants were analyzed (PDG: n = 25;73.40 ± 7.01 years / CG: n = 23;70.17 ± 8.20 years). The autonomic modulation and cardiorespiratory parameters were evaluated at rest and during the active tilt test. To assess the autonomic modulation the linear indices, at the time (rMSSD, SDNN) and frequency (LF, HF, LF/HF) domains, and the non-linear indices, obtained through the Poincaré plot (SD1, SD2, SD1/SD2), were calculated. The cardiorespiratory parameters evaluated were heart rate (HR), systolic (SBP), and diastolic blood pressure (DBP), peripheral oxygen saturation (SpO₂), and respiratory rate.

RESULTS

At rest, the PDG presented significantly lower values of rMSSD, SDNN, LF, HF, SD1, SD2, and DBP, and higher values of SpO₂. During test, in the PD group, modifications were observed in HR, and SBP, besides a reduced parasympathetic response, and an increased global modulation. The qualitative analysis of the Poincaré plot showed that the PDG has a lower dispersion of the RR intervals during rest and the active tilt test.

CONCLUSION

Individuals with PD present reduced global variability and parasympathetic modulation at rest, and reduced parasympathetic response and damage in HR regulation when performing the active tilt test, compared with controls.

Autonomic dysfunction in adults following mild traumatic brain injury: A systematic review

BACKGROUND

Increasing evidence suggests autonomic nervous system (ANS) dysfunction may occur following mild traumatic brain injury (mTBI). Measures of heart rate, heart rate variability, blood pressure and baroreceptor sensitivity can be used to evaluate ANS dysfunction following mTBI.

OBJECTIVE

Summarize the evidence for ANS dysfunction in adults following mTBI.

METHODS

A search of Embase, MEDLINE, Cochrane Central Register, PsycINFO, CINAHL and SPORTDiscus databases was conducted. Search topics included: mTBI and ANS. Identified abstracts were independently reviewed by 2 reviewers followed by full text screening. Risk of bias was assessed using a modified SIGN checklist. A structured synthesis was performed.

RESULTS

Thirty-nine studies (combined 1,467 participants diagnosed with mTBI) evaluating ANS function were included. ANS function was evaluated under various conditions including: rest, during exertion, cold pressor test, Valsalva maneuver, using face cooling and eyeball pressure paradigms. Short-term or ultra-short-term recordings were most common. The majority of studies (28/39) were rated as "unacceptable" for quality of evidence.

CONCLUSIONS

Altered parameters of ANS function have been reported in multiple conditions following mTBI, both acutely and in the post-acute/chronic stages of recovery. However, due to methodological limitations, conclusions regarding the severity and timing of ANS dysfunction following mTBI cannot be drawn.

Refractory Paroxysmal Sympathetic Hyperactivity Following Traumatic Intracerebral Hemorrhage

Paroxysmal sympathetic hyperactivity (PSH) is a complex and underrecognized phenomenon involving increased sympathetic activity leading to tachycardia, tachypnea, and hypertension. The frequency of nonrecognition is due to a lack of diagnostic criteria. In addition, the lack of evidence-based treatments has further complicated approaches to management. This case describes a patient who presented with a new-onset seizure and intracerebral hemorrhage requiring burst suppression and decompressive craniotomy to attenuate intracranial hypertension (ICH). The patient continued to display paroxysmal dysautonomia requiring a multimodal regimen for control of episodes. He demonstrated neurological improvement and complete resolution of dysautonomic activity prior to being discharged to a rehabilitation facility. A delayed diagnosis, ICH, and refractory PSH status postdecompressive craniotomy presented unique challenges. Given that the number of episodes of paroxysmal “storms” directly correlates with morbidity and mortality, early detection is critical, and lack of recognition makes this a difficult disorder to diagnose and manage.

A nationwide cross-sectional study of difficulty waking up for school among adolescents

STUDY OBJECTIVES

To determine the prevalence of and risk-factors for difficulty waking up for school among adolescents.

METHODS

We used a self-administered questionnaire (140 junior high schools [JHSs]; 124 senior high schools [SHSs]) selected randomly in 2012 from throughout Japan.

RESULTS

Total response rate: 60.7%. Data from 38,494 JHS and 61,556 SHS students were analyzed. The prevalence of at least one instance of school tardiness/absence due to difficulty waking up over a 30-day period was 10.9(95% confidence-interval:10.5-11.3)%/2.9(2.7-3.1)% for JHS-boys and 7.7(7.3-8.1)%/2.0(1.8-2.2)% for JHS-girls. The prevalence was 15.5(15.1-15.9)%/5.6(5.3-5.9)% for SHS-boys and 14.4(14.0-14.8)%/5.9(5.6-6.2)% for SHS-girls. We used ordinal regression to identify the risk factors associated with the experience of school tardiness/absence. Factors significantly associated with school tardiness in all four groups (JHS boys/girls, SHS boys/girls) were "no-participation-in-club-activities," "early-morning-awakening," "feeling bad throughout a morning," "drinking," and "smoking." Among associated factors, the highest odds ratio was found for monthly smoking-days (none vs. at least one-day or more) for JHS-girls at 5.30(3.57-7.85). Factors significantly associated with school absence in all four groups were "no wishing to go to university," "no participation in club activities," "disorders of initiating and maintaining sleep," "long internet use," "drinking," "smoking," "poor-mental-health" and "feeling bad throughout a morning." Among associated factors, the highest odds ratio was found for monthly smoking-days (none vs. at least one-day or more) for JHS-girls at 4.60(3.45-6.15).

CONCLUSIONS

These results suggest that the risk factors for difficulty waking up among adolescents are sleep status, lifestyle, and mental health, which can indicate the presence of an underlying disease.

Assessment of Functions of the Autonomic Nervous System in the Elderly with Different Comorbid Factors

Background  Studies in healthy elderly patients have shown the prevalence of autonomic dysfunction (AD) in the range of 20 to 30%. However, there is paucity in data pertaining to AD in the elderly in the Indian context. Objective  To assess the prevalence of AD in the elderly irrespective of their comorbidity status. Methods  A total of 141 elderly patients with or without comorbidities/symptoms of AD were included. Demographic and clinical details of the patients were recorded. Autonomic function tests (AFTs) such as deep breathing test, Valsalva ratio, orthostatic heart rate (OHR), isometric handgrip test, and orthostatic blood pressure were performed based on Ewing's battery of tests. The sensitivity, specificity, positive predictive value, negative predictive value, and the accuracy of AFTs were evaluated. Results  Most patients ( n  = 85) were aged between 60 and 69 years, with a male predominance (58.87%). Hypertension and diabetes mellitus were the most common comorbidities. Postural hypotension was the most common symptom of AD. With advancing age, symptoms of AD manifested significantly more. Overall, 73.8% of patients had AD, of whom 45.4% had early AD. Number of AD symptoms, glycated hemoglobin (HbA1c) level, and comorbid factors (diabetes and hypertension) were significantly associated with the results of AFTs ( p  < 0.05). AFTs were highly significant with respect to the results obtained ( p  < 0.001). Deep breathing test, abnormal in majority of study patients, has a sensitivity of 93.3% and OHR has a specificity of 81.1% to determine AD. Conclusion  The study concludes that age itself is an independent predictor of AD, which increases in severity if associated with comorbidities.

Open-label pilot study: Non-invasive vagal nerve stimulation improves symptoms and gastric emptying in patients with idiopathic gastroparesis

BACKGROUND

Gastroparesis, a chronic motility disorder characterized by delayed gastric emptying, abdominal pain, nausea, and vomiting, remains largely unexplained. Medical therapy is limited, reflecting the complex physiology of gastric sensorimotor function. Vagus nerve stimulation is an attractive therapeutic modality for gastroparesis, but prior methods required invasive surgery. In this open-label pilot study, we aimed to assess the benefit of non-invasive vagal nerve stimulation in patients with mild to moderate idiopathic gastroparesis.

METHODS

Patients self-administered the gammaCore vagal nerve stimulator for 4 weeks. The gastroparesis cardinal symptom index daily diary (GCSI-dd) was assessed during a two-week run-in period, ≥4 weeks of therapy, and 4 weeks after therapy was completed. Gastric emptying and autonomic function testing were also performed. The primary endpoint was an absolute reduction in CGSI-dd of 0.75 after nVNS.

RESULTS

There was a total improvement in symptom scores (2.56 ± 0.76 to 1.87 ± 1.05; P = .01), with 6/15 (40%) participants meeting our primary endpoint. Therapy was associated with a reduction in gastric emptying (T1/2 155 vs 129 minutes; P = .053, CI -0.4 to 45). Therapy did not correct autonomic function abnormalities, but was associated with modulation of reflex parasympathetic activity.

CONCLUSIONS

Short-term non-invasive vagal nerve stimulation led to improved cardinal symptoms and accelerated gastric emptying in a subset of patients with idiopathic gastroparesis. Responders had more severe gastric delay at baseline and clinical improvement correlated with duration of therapy, but not with improvements in gastric emptying. Larger randomized sham-controlled trials of greater duration are needed to confirm the results of this pilot study.

HIV Infection Is Associated With Variability in Ventricular Repolarization: The Multicenter AIDS Cohort Study (MACS)

BACKGROUND

People living with human immunodeficiency virus (HIV+) have greater risk for sudden arrhythmic death than HIV-uninfected (HIV-) individuals. HIV-associated abnormal cardiac repolarization may contribute to this risk. We investigated whether HIV serostatus is associated with ventricular repolarization lability by using the QT variability index (QTVI), defined as a log measure of QT-interval variance indexed to heart rate variance.

METHODS

We studied 1123 men (589 HIV+ and 534 HIV-) from MACS (Multicenter AIDS Cohort Study), using the ZioXT ambulatory electrocardiography patch. Beat-to-beat analysis of up to 4 full days of electrocardiographic data per participant was performed using an automated algorithm (median analyzed duration [quartile 1-quartile 3]: 78.3 [66.3-83.0] hours/person). QTVI was modeled using linear mixed-effects models adjusted for demographics, cardiac risk factors, and HIV-related and inflammatory biomarkers.

RESULTS

Mean (SD) age was 60.1 (11.9) years among HIV- and 54.2 (11.2) years among HIV+ participants (P<0.001), 83% of whom had undetectable (<20 copies/mL) HIV-1 viral load (VL). In comparison with HIV- men, HIV+ men had higher QTVI (adjusted difference of +0.077 [95% CI, +0.032 to +0.123]). The magnitude of this association depended on the degree of viremia, such that in HIV+ men with undetectable VL, adjusted QTVI was +0.064 (95% CI, +0.017 to +0.111) higher than in HIV- men, whereas, in HIV+ men with detectable VL, adjusted QTVI was higher by +0.150 (95% CI, 0.072-0.228) than in HIV- referents. Analysis of QTVI subcomponents showed that HIV+ men had: (1) lower heart rate variability irrespective of VL status, and (2) higher QT variability if they had detectable, but not with undetectable, VL, in comparison with HIV- men. Higher levels of C-reactive protein, interleukin-6, intercellular adhesion molecule-1, soluble tumor necrosis factor receptor 2, and soluble cluster of differentiation-163 (borderline), were associated with higher QTVI and partially attenuated the association with HIV serostatus.

CONCLUSIONS

HIV+ men have greater beat-to-beat variability in QT interval (QTVI) than HIV- men, especially in the setting of HIV viremia and heightened inflammation. Among HIV+ men, higher QTVI suggests ventricular repolarization lability, which can increase susceptibility to arrhythmias, whereas lower heart rate variability signals a component of autonomic dysfunction.

Brain Responses in CFS and TMD to Autonomic Challenges: An Exploratory fMRI Study

INTRODUCTION

Dysfunction of the autonomic nervous system (ANS) is seen in chronic fatigue syndrome (CFS) and temporomandibular disorders (TMDs). Both conditions have poorly understood pathophysiology. Several brain structures that play a role in pain and fatigue, such as the insular cortex and basal ganglia, are also implicated in autonomic function.

OBJECTIVES

ANS dysfunction may point to common neurophysiologic mechanisms underlying the predominant symptoms for CFS and TMD. No studies to date have investigated the combination of both conditions. Thus, our aim was to test whether patients with CFS with or without TMD show differences in brain responses to autonomic challenges.

METHODS

In this exploratory functional imaging study, patients with CFS who screened positive for TMD (n = 26), patients who screened negative for TMD (n = 16), and age-matched control participants (n = 10) performed the Valsalva maneuver while in a 3-T magnetic resonance imaging scanner. This maneuver is known to activate the ANS.

RESULTS

For all 3 groups, whole-brain F test showed increased brain activation during the maneuver in the superior and inferior frontal gyri, the left and right putamen and thalamus, and the insular cortex. Furthermore, group contrasts with small-volume correction showed that patients with CFS who screened positive for TMD showed greater activity in the left insular cortex as compared with patients who screened negative and in the left caudate nucleus as compared with controls.

CONCLUSION

Our results suggest that increased activity in the cortical and subcortical regions observed during autonomic challenges may be modulated by fatigue and pain. ANS dysfunction may be a contributing factor to these findings, and further work is required to tease apart the complex relationship among CFS, TMD, and autonomic functions.

KNOWLEDGE TRANSFER STATEMENT

Brain activity related to activation of the autonomic nervous system in patients with chronic fatigue syndrome who screened positive for painful temporomandibular disorder was greater than in patients who screened negative; activity was seen in brain regions associated with autonomic functions and pain. These findings suggest that autonomic dysfunction may play a role in the pathophysiology of both conditions, explain some of the apparent comorbidity between them, and offer avenues to help with treatment.

Postural orthostatic tachycardia syndrome: clinical presentation, aetiology and management

Postural orthostatic tachycardia syndrome (POTS) is a variant of cardiovascular autonomic disorder characterized by an excessive heart rate increase on standing and orthostatic intolerance. POTS affects younger individuals 15-45 years old with a distinct female predominance (≈80%). The prevalence ranges between 0.2% and 1.0% in developed countries. The onset of POTS is typically precipitated by immunological stressors such as viral infection, vaccination, trauma, pregnancy, surgery or psychosocial stress. The most common complaints are dizziness, weakness, rapid heartbeat and palpitation on standing. Moreover, patients often report physical deconditioning and reduced exercise capacity as well as headache, 'brain fog', dyspnoea, gastrointestinal disorders and musculoskeletal pain. The aetiology of POTS is largely unknown and three main hypotheses include an autoimmune disorder, abnormally increased sympathetic activity and catecholamine excess, and sympathetic denervation leading to central hypovolaemia and reflex tachycardia. The golden standard for POTS diagnosis is head-up tilt test with a non-invasive beat-to-beat haemodynamic monitoring. Although long-term prognosis of POTS is poorly explored, around 50% of patients spontaneously recover within 1-3 years. After the diagnosis has been established, patient should be thoroughly educated about non-pharmacological measures alleviating the symptoms. Exercise training may be very effective and counteract deconditioning. In more symptomatic patients, different drugs directed at controlling heart rate, increasing peripheral vasoconstriction and intravascular volume can be tested. However, the overall effects of pharmacological therapy are modest and the most affected patients remain handicapped. Future efforts should focus on better understanding of POTS pathophysiology and designing randomized controlled trials for selection of more effective therapy.

Intrathecal baclofen in paroxysmal sympathetic hyperactivity: Impact on oral treatment

INTRODUCTION

Intrathecal baclofen (ITB) is a commonly used treatment in severe spasticity. The main objective of this study was to assess the impact of ITB on reduction or withdrawal of oral drugs in patients with paroxysmal sympathetic hyperactivity (PSH) after severe traumatic brain injury.

METHODS

We retrospectively evaluated 20 patients with PSH due to severe traumatic brain injury who were treated with ITB in a primary care and referral center of neurology. Rates of and time until complete withdrawal or possible reduction in oral baclofen and oral propranolol after ITB treatment were calculated. Moreover, vegetative parameters (heart rate and blood pressure) as well as hypertonic attacks were assessed.

RESULTS

The median time of complete oral baclofen disposal was 5 ± 3.7 (CI 95% [2.9-7.1], range 0-14) days after ITB pump implantation in 20 of 20 patients, and the median time of complete oral propranolol disposal was 24 ± 62.97 (CI 95% [-7.87-55.87], range 5-191) in 15 of 20 patients. With ITB treatment, PSH improved promptly in all patients with alleviation of heart rate and blood pressure as well as reduction in attacks with motor phenomena. ITB treatment was safe and without complications.

CONCLUSIONS

ITB might facilitate cutting back or dispensing with other conventional oral drugs, such as oral baclofen and oral propranolol. Our study provides further evidence that ITB treatment should be considered in patients with otherwise medically refractory PSH in severe traumatic brain injury. Further prospective multicenter studies are needed to confirm the findings of this study.

Eleven years' experience with Intrathecal Baclofen - Complications, risk factors

OBJECTIVE

Treatment with intrathecal baclofen (ITB) is commonly used in patients with severe spasticity. However, complications may occur after implantation of the ITB-device, albeit mainly procedure- and device-related problems. The aim of the study was to assess surgical- as well as catheter- and pump-related complications and define their risk factors.

METHODS

We retrospectively evaluated all patients with an implanted ITB-device who were treated at the Department of Neurology, Hochzirl Hospital, Zirl, Austria, between 2006 and 2016.

RESULTS

Twenty-nine of 116 (25%) patients experienced 32 complications: 5 procedure- and 27 device-related (4 pump- and 23 catheter-associated) problems occurred. Risk factors for sustaining any complication were a spinal localization of lesion (odds ratio [OR] OR 2.71, p = .021), other catheter types than an Ascenda^® catheter (OR 3.87, p = .041), a lower modified Rankin Scale (median 4 vs. 5; OR 2.86, p = .015) and a higher Barthel Index (median 53 vs. 0; OR 2.84, p = .006). The median time from the last ITB-related surgery to the first complication was 18 (IQR 1-57) months. Overall, 47% complications occurred within the first year after any surgical procedure regarding the ITB-device, thereof 25% within the first month.

CONCLUSIONS

Procedure- and device-related complications are frequent after implantation of an ITB-device with catheter-associated complications as the most frequently encountered problems. Patients with a spinal origin of spasticity, a lower modified Rankin Scale and a higher Barthel Index have a higher risk to sustain a complication.

Autonomic Neuropathy-a Prospective Cohort Study of Symptoms and E/I Ratio in Normal Glucose Tolerance, Impaired Glucose Tolerance, and Type 2 Diabetes

Background

Autonomic neuropathy in diabetes, in addition to causing a range of symptoms originating from the autonomic nervous system, may increase cardiovascular morbidity. Our aim was to study the progression of autonomic neuropathy, based on symptom score and evaluation of an autonomic test, in persons with normal and impaired glucose tolerance and in patients with type 2 diabetes (T2D).

Methods

Participants were recruited in 2003/2004 with a follow-up in 2014. The participants’ glucose tolerance was categorized using oral glucose tolerance tests. Symptoms were evaluated using an autonomic symptom score (ASS), ECG was used to test cardiac autonomic function based on the expiration/inspiration ratio (E/I ratio), and blood samples were taken on both occasions.

Results

ASSs were higher at follow-up in the T2D patients than in the normal glucose tolerance group (mean 1.21 ± 1.30 vs. 0.79 ± 0.7; p < 0.05). E/I ratio did not deteriorate more than could be expected as an aging effect in well-controlled T2D. No relationship was found between E/I ratio and HbA1c or ASS.

Conclusion

The presence of autonomic symptoms increased over time in T2D patients, but the symptoms did not correlate with the E/I ratio in this metabolically well-controlled cohort. ASSs can be a useful clinical tool when assessing the progression of autonomic dysfunction in patients with abnormal glucose metabolism.

Autoimmune Voltage-Gated Potassium Channelopathy Presenting With Catecholamine Excess

BACKGROUND

Autoimmune voltage-gated potassium channelopathies have been associated with a range of neurological presenting symptoms, including central, peripheral, and autonomic dysfunction.

PATIENT DESCRIPTION

We describe a 12-year-old boy who presented with nine months of pain, anxiety, and 30-pound weight loss. He was admitted for failure to thrive, then noted to be persistently hypertensive and tachycardic. Plasma metanephrines and urine metanephrines and catecholamines were elevated. Extensive investigation for causes of elevated catecholamines, such as hyperthyroidism or catecholamine-secreting tumor, was negative. A paraneoplastic panel was positive for voltage-gated potassium channel antibodies. Treatment with intravenous immunoglobulin and pulse methylprednisolone led to complete resolution of symptoms, weight gain, and normalization of vital signs and plasma metanephrines.

CONCLUSION

Voltage-gated potassium channel antibodies should be considered as part of the differential in patients presenting with elevated metanephrine and catecholamine secretion.

A Chinese Decoction, Kuan-Sin-Yin, Improves Autonomic Function and Cancer-Related Symptoms of Metastatic Colon Cancer

BACKGROUND

Kuan-Sin-Yin (KSY) is a traditional Chinese medicine (TCM) decoction, which has been shown to have cytostatic effects on cancer cells and involved in the TCM theory of promoting yin-yang balance.Sonce many cancer patients suffer from autonomic dysfunction (AD), which correspond to yin-yang imbalance in TCM. The aim of this study is to evaluate the possible effect of KSY in metastatic colon cancer (mCRC) patients with AD.

METHODS

We conducted a single-group experiment. Total 52 qualified patients were enrolled. Participants took the KSY daily for 2 weeks. The primary outcome was KSY efficacy as reflected in the heart rate variability (HRV) and electrical conductivity (µA) over 12 meridian points. Autonomic function was examined before and after the KSY intervention. The vagal and sympathetic tone were recorded by HRV; 12 meridian energies were measured using a meridian energy analysis device. Secondary outcomes were cancer-related symptoms and patient quality of life (QoL).

RESULTS

The results showed that the KSY intervention improved AD via increasing the vagal tone (HF: P = .041), but not the sympathetic tone (LF: P = .154); total autonomic activity was significantly enhanced (HRV activity: P = .013). Intriguingly, energy increased more over the yin meridian (P = .010) than over the yang meridian (P = .015). Cancer-related symptoms and QoL were significantly improved (P < .05).

CONCLUSION

The safety and effectiveness of KSY in improving AD in mCRC patients are through regulating the vagal-sympathetic dynamic balance, which correspond to the TCM yin-yang concept of energy.

Morphine: An Effective Abortive Therapy for Pediatric Paroxysmal Sympathetic Hyperactivity After Hypoxic Brain Injury

Paroxysmal sympathetic hyperactivity (PSH) is a life-threatening condition characterized by hyperadrenergic activity and autonomic dysfunction. Also termed autonomic storms, PSH can occur after a variety of cerebral insults, most commonly traumatic brain injury. Limited pediatric literature is available, especially in patients with brain injury from hypoxia. No consensus exists for the terminology, diagnostic criteria, or treatment algorithm for PSH. Thus, the optimal management, including medication selection and dosing, remains unclear. We present the detailed treatment of a 9-year-old, African American male with hypoxic brain injury after pulseless arrest following status asthmaticus, who subsequently developed PSH. The patient began to experience episodes of tachycardia, hypertension, tachypnea, diaphoresis, rigidity, and dystonic posturing on hospital day 5. After ruling out other potential causes, a diagnosis of PSH was made. Episodes of PSH failed to respond to lorazepam or labetalol but were aborted successfully with morphine. Management of PSH after hypoxic brain injury required medications for acute treatment as well as for prevention of PSH. Morphine was found to be highly effective and safe for aborting the autonomic crises. Other agents more commonly described in the literature did not result in an adequate response and were associated with significant adverse effects. A combination of clonazepam, baclofen, and either propranolol or clonidine aided in reducing the frequency of episodes of PSH. We suggest using morphine for aborting severe episodes of PSH that do not respond to antihypertensive agents or benzodiazepines.

Treatment of gastrointestinal sphincters spasms with botulinum toxin A

Botulinum toxin A inhibits neuromuscular transmission. It has become a drug with many indications. The range of clinical applications has grown to encompass several neurological and non-neurological conditions. One of the most recent achievements in the field is the observation that botulinum toxin A provides benefit in diseases of the gastrointestinal tract. Although toxin blocks cholinergic nerve endings in the autonomic nervous system, it has also been shown that it does not block non-adrenergic non-cholinergic responses mediated by nitric oxide. This has promoted further interest in using botulinum toxin A as a treatment for overactive smooth muscles and sphincters. The introduction of this therapy has made the treatment of several clinical conditions easier, in the outpatient setting, at a lower cost and without permanent complications. This review presents current data on the use of botulinum toxin A in the treatment of pathological conditions of the gastrointestinal tract.

Survival of a patient with tetanus in Bhutan using a magnesium infusion managed only by clinical signs

Tetanus is a life-threatening disease that continues to have a high prevalence in developing countries. Severe muscle spasms often require patients to receive tracheostomy, high-dose sedatives, and sometimes prolonged neuromuscular blockade. Magnesium sulfate (MgSO4) infusion has great promise as an adjunct treatment for severe tetanus, as it may allow clinicians to decrease the dose of other sedative medications. Although the mechanism of action of MgSO4 is not well understood, it appears to attenuate both the muscle spasms and autonomic instability associated with severe tetanus infections. However, MgSO4 infusions are often managed based on serial measurements of serum magnesium levels and other laboratory tests such as arterial blood gases, which can be difficult to obtain in resource-poor settings. We describe a case of severe tetanus in Bhutan managed through the use of magnesium infusion titrated solely to physical examination findings.

Reduced heart rate variability is associated with worse cognitive performance in elderly Mexican Americans

Reduced heart rate variability is a strong predictor of cardiovascular risk factors, cardiovascular events, and mortality and thus may be associated with cognitive neurodegeneration. Yet, this has been relatively unexplored, particularly in minority populations with high cardiovascular burden. We used data from the Sacramento Area Latino Study on Aging to examine the cross-sectional association of reduced heart rate variability with cognitive function among elderly Mexican Americans. A total of 869 participants (mean age, 75 years; 59% women) had their 6-minute heart rate variability measured using an ECG monitor and respiration pacer in response to deep breathing. We used the mean circular resultant, known as R bar, as a measure of heart rate variability and categorized it into quartiles (Q1 to Q4 of R bar: reduced to high heart rate variability). Cognitive function was assessed using the modified Mini-Mental State Examination, a 100-point test of global cognitive function, and the Spanish and English verbal learning test, a 15-point test of verbal memory recall. In fully adjusted linear regression models, participants in quartile 1 had a 4-point lower modified Mini-Mental State Examination score (P<0.01), those in quartile 2 had a 2-point lower score (P=0.04), and those in quartile 3 had a 1-point lower score (P=0.35) compared with those in the highest quartile of R bar. Reduced R bar was not associated with verbal memory. Our results suggest that reduced heart rate variability is associated with worse performance on the test of global cognitive function, above and beyond traditional cardiovascular risk factors.

Sinus arrest during radiofrequency ablation of the atrioventricular-node slow pathway: implications and possible mechanisms

Radiofrequency ablation has been associated with changes in autonomic function. In this case, a 52-year-old woman was referred for electrophysiologic study of recurrent supraventricular tachycardia. Typical slow/fast atrioventricular node re-entry tachycardia was induced and confirmed during the study. Radiofrequency ablation of the slow pathway of the atrioventricular node led to sinus arrest, which resolved once ablation was stopped. Given the distance of the ablation site from the sinus node, we inferred that mechanisms other than direct injury to the sinus node were involved. To our knowledge, this is only the 2nd reported finding of sinus arrest during slow-pathway ablation of the atrioventricular node. This case highlights the complex interaction between the autonomic nervous system and the cardiac conduction system. Possible mechanisms include a Bezold-Jarisch reflex and modification of the intrinsic autonomic nervous system.

[Diabetic autonomic neuropathy diagnosed in primary care in patients with type 2 diabetes]

OBJECTIVE

To determine the prevalence of diabetic autonomic neuropathy (DAN) in patients with type 2 diabetes using a cardiovascular test.

DESIGN

Observational, descriptive, cross-sectional study.

SETTING

Primary care clinics in Fronteras de Torrejón de Ardoz Health Centre, Area 3, Madrid, Spain.

PARTICIPANTS

Of the 361 diabetics assigned to 3 participating patient quotas, 317 patients had type 2 diabetes. Of those, 104 were excluded due to being immobile, cardiac arrhythmia, and/or on treatment with chronotropic drugs. Of the 213 patients included, 169 had the test and 44 were lost.

INTERVENTIONS

Performing of the orthostatic response test.

MAIN MEASUREMENTS

Age, sex, years since diagnosed with diabetes (measured by patient anamnesis), treatment (hygiene-diet measures, oral antidiabetics, insulin) were recorded, along with the R-R'30:15 ratio (classified as normal: 31.04, borderline: 1.01 to 1.03, and pathological: pound1.00).

RESULTS

The prevalence of DAN using the orthostatic response test was 56.2% (95 patients with a pathological R-R'30:15 index) out of a total of 169 patients with type 2 diabetes. The definitive diagnosis of DAN found in the clinical histories reviewed was 1.8%.

CONCLUSIONS

DAN goes unnoticed in our evaluation of the patient with diabetes. The improvement in diagnosing this complication and incorporating cardiovascular autonomic dysfunction tests in primary care follow-up protocols, would enable closer metabolic control and improve the prognosis of the disease.