Tag: dysautonomia

Assessment of Prolonged Physiological and Behavioral Changes Associated With COVID-19 Infection

Introduction: Long-term COVID symptoms marked by autonomic dysfunction1 and cardiac damage2 following COVID-19 infection have been noted for up to 6 months after symptom onset,3 but to date have not been quantified, to our knowledge. Previous studies have found that wearable data can improve real-time detection of viral illness4 or discrimination of individuals with COVID-19 vs other viral infections.5 Wearable devices provide a way to continuously track an individual’s physiological and behavioral metrics beginning when healthy (ie, before infection), during the course of infection, and recovery back to baseline. In this cohort study, we aimed to examine the duration and variation of recovery among COVID-19–positive vs COVID-19–negative participants.
Methods: DETECT (Digital Engagement and Tracking for Early Control and Treatment) is a remote, app-based, longitudinal research study enrolling adult participants from all over the US and collecting their wearable data to better understand individual changes associated with viral illness, including COVID-19. All participants provided informed consent electronically. The protocol for this study was reviewed and approved by the Scripps Office for the Protection of Research Subjects. This study follows the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline.

From March 25, 2020, through January 24, 2021, 37 146 participants were enrolled. This analysis focuses on 875 individuals who reported symptoms of an acute respiratory illness and underwent swab testing for COVID-19 and were found to be either positive (234 individuals) or negative (641 individuals) (eFigure in the Supplement).

The following calculation was used for resting heart rate (RHR): deviation from baseline = daily RHR − baseline RHR mean. Individuals with COVID-19 were also grouped by their mean RHR deviation from baseline 28 to 56 days after symptom onset (<1, 1-5, or >5 beats per minute).

Data analysis was conducted in SAS statistical software version 9.4 (SAS Institute). Significance was set at P < .05. P values were calculated with 1-way ANOVA (for mean age) or χ2 tests. Additional details about our methods can be found in the eAppendix in the Supplement.

Results: For this analysis, our study population consisted of 234 COVID-19–positive individuals (mean [range] age, 45.3 [18-76] years; 164 women [70.9%]) and 641 COVID-19–negative symptomatic individuals (mean [range] age, 44.7 [19-75] years; 455 women [71.1%]). Individuals with COVID-19 took longer to return to their RHR (Figure, A and B), sleep (Figure, C and D), and activity (Figure, E and F) baselines compared with symptomatic individuals who were COVID-19 negative. This difference was most marked for RHR, with COVID-19–positive individuals initially experiencing a transient bradycardia followed by a prolonged relative tachycardia that did not return to baseline, on average, until 79 days after symptom onset. Step count and sleep quantity returned to baseline sooner than RHR at 32 and 24 days, respectively. During recovery, individuals with COVID-19 experienced different trajectories in the return of their RHR to their normal compared with COVID-19–negative individuals (Figure, B). A small subset of COVID-19–positive participants (32 participants [13.7%]) maintained an RHR more than 5 beats per minute greater than their baseline RHR that did not return to their normal for more than 133 days. During the acute phase of COVID-19, individuals in this group reported higher frequencies of cough (27 participants [84.4%] vs 57 participants [55.3%] in the <1 beat per minute group and 57 participants [57.6%] in the 1-5 beats per minute group), body ache (20 participants [62.5%] vs 42 participants [40.8%] in the <1 beat per minute group and 35 participants [35.4%] in the 1-5 beats per minute group), and shortness of breath (9 participants [28.1%] vs 9 participants [8.7%] in the <1 beat per minute group and 6 participants [6.1%] in the 1-5 beats per minute group) compared with the other groups (Table).
Discussion: To our knowledge, this is the first study to examine longer duration wearable sensor data. We found a prolonged physiological impact of COVID-19 infection, lasting approximately 2 to 3 months, on average, but with substantial intraindividual variability, which may reflect various levels of autonomic nervous system dysfunction or potentially ongoing inflammation. Transient bradycardia has been noted in a case study6 approximately 9 to 15 days after symptom onset, which was also seen in our population. Our data suggest that early symptoms and larger initial RHR response to COVID-19 infection may be associated with the physiological length of recovery from this virus.

Symptom data were collected only during the acute phase of infection, which limited our ability to compare long-term physiological and behavioral changes with long-term symptoms. In the future, with larger sample sizes and more comprehensive participant-reported outcomes, it will be possible to better understand factors associated with interindividualized variability in COVID-19 recovery.

Source: Radin JM, Quer G, Ramos E, et al. Assessment of Prolonged Physiological and Behavioral Changes Associated With COVID-19 Infection. JAMA Netw Open. 2021;4(7):e2115959. doi:10.1001/jamanetworkopen.2021.15959 https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2781687 (Full article)

Reduced Heart Rate Variability in Patients with Medically Unexplained Physical Symptoms: A Meta-Analysis of HF-HRV and RMSSD

Abstract:

Objectives: Medically unexplained physical symptoms (MUPS) and related syndromes are common and place a substantial burden on both patients and society. Chronic psychological distress and dysregulation of the autonomic nervous system may be common factors associated with MUPS, although previous studies have reported mixed results. The aim of this meta-analysis is to provide an updated synthesis of studies investigating heart rate variability (HRV) indices associated with autonomic nervous system functioning in three common MUPS-syndromes and to explain inconsistencies in previous study findings.

Method: Literature search yielded 58 studies comparing HRV indices of reduced parasympathetic activity of healthy individuals to patients with chronic fatigue syndrome (Npatients = 271), irritable bowel syndrome (Npatients = 1005), and fibromyalgia (Npatients = 534). Separate random-effects meta-analyses were conducted on studies measuring root mean square of successive differences (RMSSD) and high frequency HRV (HF-HRV).

Results: Regardless of syndrome type, patients had significantly lower RMSSD (k = 22, Hedges’ g = – 0.37 [-0.53; -0.21], p < .001) and HF-HRV (k = 52, Hedges’ g = -0.69 [-1.03; -0.36], p < .001) than healthy individuals. Sample age and publication year explained substantial variation in RMSSD, whereas controlling for confounders in statistical analyses explained variation in HF-HRV.

Conclusions: Lower RMSSD and HF-HRV in patients with MUPS versus healthy controls indicates that autonomic nervous system dysregulation, particularly lower parasympathetic activity, may play a role in patients with these conditions. This conclusion may have important implications for the underlying mechanisms and treatment of MUPS and related syndromes.

Source: Vreijling SR, Troudart Y, Brosschot JF. Reduced Heart Rate Variability in Patients with Medically Unexplained Physical Symptoms: A Meta-Analysis of HF-HRV and RMSSD. Psychosom Med. 2020 Oct 14. doi: 10.1097/PSY.0000000000000874. Epub ahead of print. PMID: 33065584. https://pubmed.ncbi.nlm.nih.gov/33065584/

Autonomic Phenotypes in Chronic Fatigue Syndrome (CFS) Are Associated with Illness Severity: A Cluster Analysis

Abstract:

In this study we set out to define the characteristics of autonomic subgroups of patients with Chronic Fatigue Syndrome (CFS). The study included 131 patients with CFS (Fukuda criteria). Participants completed the following screening symptom assessment tools: Chalder Fatigue Scale, Fatigue Impact Scale, Fatigue Severity Scale, Epworth Sleepiness Scales, the self-reported Composite Autonomic Symptom Scale. Autonomic parameters were measured at rest with a Task Force Monitor (CNS Systems) and arterial stiffness using an Arteriograph (TensioMed Kft.).

Principal axis factor analysis yielded four factors: fatigue, subjective and objective autonomic dysfunction and arterial stiffness. Using cluster analyses, these factors were grouped in four autonomic profiles: 34% of patients had sympathetic symptoms with dysautonomia, 5% sympathetic alone, 21% parasympathetic and 40% had issues with sympathovagal balance.

Those with a sympathetic-dysautonomia phenotype were associated with more severe disease, reported greater subjective autonomic symptoms with sympathetic over-modulation and had the lowest quality of life. The highest quality of life was observed in the balance subtype where subjects were the youngest, had lower levels of fatigue and the lowest values for arterial stiffness. Future studies will aim to design autonomic profile-specific treatment interventions to determine links between autonomic phenotypes CFS and a specific treatment.

Source: Słomko J, Estévez-López F, Kujawski S, et al. Autonomic Phenotypes in Chronic Fatigue Syndrome (CFS) Are Associated with Illness Severity: A Cluster Analysis. J Clin Med. 2020;9(8):E2531. Published 2020 Aug 5. doi:10.3390/jcm9082531  https://www.mdpi.com/2077-0383/9/8/2531  (Full text)

Complex syndromes of chronic pain, fatigue and cognitive impairment linked to autoimmune dysautonomia and small fiber neuropathy

Abstract:

Chronic fatigue syndrome, postural orthostatic tachycardia syndrome, complex regional pain syndrome and silicone implant incompatibility syndrome are a subject of debate among clinicians and researchers. Both the pathogenesis and treatment of these disorders require further study.

In this paper we summarize the evidence regarding the role of autoimmunity in these four syndromes with respect to immunogenetics, autoimmune co-morbidities, alteration in immune cell subsets, production of autoantibodies and presentation in animal models. These syndromes could be incorporated in a new concept of autoimmune neurosensory dysautonomia with the common denominators of autoantibodies against G-protein coupled receptors and small fiber neuropathy.

Sjogren’s syndrome, which is a classical autoimmune disease, could serve as a diseases model, illustrating the concept. Development of this concept aims to identify an apparently autoimmune subgroup of the disputable disorders, addressed in the review, which may mostly benefit from the immunotherapy.

Copyright © 2020. Published by Elsevier Inc.

Source: Shoenfeld Y, Ryabkova VA, Sheibenbogen C, Brinth L, Martinez-Lavin M, Ikeda S, Heidecke H, Watad A, Bragazzi NL, Chapman J, Churilov LP, Amital H. Complex syndromes of chronic pain, fatigue and cognitive impairment linked to autoimmune dysautonomia and small fiber neuropathy. Clin Immunol. 2020 Mar 11:108384. doi: 10.1016/j.clim.2020.108384. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/32171889

Network structure underpinning (dys)homeostasis in chronic fatigue syndrome; Preliminary findings

Abstract:

INTRODUCTION: A large body of evidence has established a pattern of altered functioning in the immune system, autonomic nervous system and hypothalamic pituitary adrenal axis in chronic fatigue syndrome. However, the relationship between components within and between these systems is unclear. In this paper we investigated the underlying network structure of the autonomic system in patients and controls, and a larger network comprising all three systems in patients alone.

METHODS: In a sample of patients and controls we took several measures of autonomic nervous system output during 10 minutes of supine rest covering tests of blood pressure variability, heart rate variability and cardiac output. Awakening salivary cortisol was measured on each of two days with participants receiving 0.5mg dexamethasone during the afternoon of the first day. Basal plasma cytokine levels and the in vitro cytokine response to dexamethasone were also measured. Symptom outcome measures used were the fatigue impact scale and cognitive failures questionnaire. Mutual information criteria were used to construct networks describing the dependency amongst variables. Data from 42 patients and 9 controls were used in constructing autonomic networks, and 15 patients in constructing the combined network.

RESULTS: The autonomic network in patients showed a more uneven distribution of information, with two distinct modules emerging dominated by systolic blood pressure during active stand and end diastolic volume and stroke volume respectively. The combined network revealed strong links between elements of each of the three regulatory systems, characterised by three higher modules the centres of which were systolic blood pressure during active stand, stroke volume and ejection fraction respectively.

CONCLUSIONS: CFS is a complex condition affecting physiological systems. It is important that novel analytical techniques are used to understand the abnormalities that lead to CFS. The underlying network structure of the autonomic system is significantly different to that of controls, with a small number of individual nodes being highly influential. The combined network suggests links across regulatory systems which shows how alterations in single nodes might spread throughout the network to produce alterations in other, even distant, nodes. Replication in a larger cohort is warranted.

Source: Clark JE, Ng WF, Rushton S, Watson S, Newton JL. Network structure underpinning (dys)homeostasis in chronic fatigue syndrome; Preliminary findings. PLoS One. 2019 Mar 25;14(3):e0213724. doi: 10.1371/journal.pone.0213724. eCollection 2019. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0213724 (Full article)

The effects of warm water immersion on blood pressure, heart rate and heart rate variability in people with chronic fatigue syndrome

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS) is a central sensitisation syndrome with abnormalities in autonomic regulation of blood pressure (BP), heart rate (HR) and heart rate variability (HRV). Prior to exploring the effects of hydrotherapy as a treatment for this population, changes in BP, HR and HRV during warm water immersion need to be established.

OBJECTIVES: The study aimed to determine the effects of warm water immersion on BP, HR and HRV in adults with CFS compared to matched-pair healthy adults.

METHOD: A quasi-experimental, single-blinded study design was used with nine CFS participants and nine matched controls. Participants’ BP, HR and HRV were measured before, after 5 minutes and post warm water immersion at the depth of the fourth intercostal space, using the Ithlete® System and Dräger BP monitor.

RESULTS: There was a significant difference between groups in HRV prior to immersion (control group: 73 [55-74] vs. chronic fatigue syndrome group: 63 [50-70]; p = 0.04). There was no difference in HRV post-immersion. A significant difference in HR after immersion was recorded with the control group having a lower HR than those with CFS (78 [60-86] vs. 86 [65-112]; p = 0.03). The low HRV present in the CFS group prior to immersion suggests autonomic dysregulation. Individuals with CFS may have reduced vagal nerve activation post-immersion. During immersion, HRV of the CFS participants improved similar to that of the healthy controls.

CONCLUSION: Prior to immersion, differences were present in the HRV of the participants with CFS compared to healthy controls. These differences were no longer present post-immersion.

CLINICAL IMPLICATIONS: Warm water immersion appears safe and may be beneficial in the management of individuals with CFS.

Source: Parker R, Higgins Z, Mlombile ZNP, Mohr MJ, Wagner TL. The effects of warm water immersion on blood pressure, heart rate and heart rate variability in people with chronic fatigue syndrome. S Afr J Physiother. 2018 Aug 28;74(1):442. doi: 10.4102/sajp.v74i1.442. eCollection 2018. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6131699/ (Full article)

Cardiac sympathetic innervation associates with autonomic dysfunction in chronic fatigue syndrome – a pilot study

Despite hemodynamic abnormalities being well documented in chronic fatigue syndrome (CFS), it remains unclear the nature of the underlying autonomic nervous system problems that underpin these findings. Studies performed in subgroups of those with CFS suggest cardiac sympathetic denervation.

Meta-iodo-benzylguanidine (MIBG) imaging provides a quantitative measure of cardiac sympathetic innervation. Clinically, cardiac MIBG scanning is used to estimate local myocardial sympathetic nerve damage in heart disease and dysautonomia, particularly abnormalities arising due to sympathetic innervation [1,2]. In this study, we explored potential mechanisms that underpin the autonomic abnormalities seen in CFS using I125 MIBG participants that fulfilled Fukuda diagnostic criteria for CFS [3]. Participants were excluded if screened positive for a major depressive episode (Structured Clinical Interview for the Diagnostic and Statistical Manual for Mental Disorders). Fatigue was measured using the Fatigue Impact Scale (FIS).

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Source: Petrides G, Zalewski P, McCulloch D, Maclachlan L, Finkelmeyer A, Hodgson T, Blamire A, Newton JL. Cardiac sympathetic innervation associates with autonomic dysfunction in chronic fatigue syndrome – a pilot study. Fatigue. 2017 May 4;5(3):184-186. doi: 10.1080/21641846.2017.1322235. eCollection 2017. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5942146/ (Full article)

Autonomic Nervous System Functioning Related to Nocturnal Sleep in Patients With Chronic Fatigue Syndrome Compared to Tired Controls

Abstract:

STUDY OBJECTIVES: Autonomic nervous system (ANS) dysfunction is common in chronic fatigue syndrome (CFS). One of the main complaints in CFS is unrefreshing sleep. We aimed to study the nocturnal cardiac ANS in different sleep stages in patients filling the 2015 Institute of Medicine CFS diagnostic criteria.

METHODS: In this case series study, the nocturnal heart rate variability and blood pressure (BP) variables in polysomnography were studied in groups of patients with CFS (n = 8) and tired controls (n = 8) aged 16-49 years. Five of the patients with CFS and controls were female. The heart rate variability and BP parameters and heart rate were studied in all sleep stages and wake.

RESULTS: The amount of low-frequency oscillations of the electrocardiography R-R-intervals spectra (LF; predominantly reflects sympathetic activity) was higher for patients with CFS in all sleep stages compared to controls (P< .001). During wake, the amount of LF was lower for the patients with CFS (P< .05). The amount of high-frequency oscillations (HF; reflects parasympathetic activity) was lower in stage N3 sleep in the patients with CFS than for the controls (P< .0001), but, in total, HF was higher in patients with CFS (P< .001). Patients with CFS had higher overall nocturnal systolic and mean BP (P< .0001) and lower heart rate (P< .0001) than controls. No significant differences were found in sleep stage distributions.

CONCLUSIONS: The results suggest a nocturnal dysfunction of the cardiac ANS in CFS, presenting as lower parasympathetic tone in deep sleep and higher sympathetic tone asleep.

Source: Orjatsalo M, Alakuijala A, Partinen M. Autonomic Nervous System Functioning Related to Nocturnal Sleep in Patients With Chronic Fatigue Syndrome Compared to Tired Controls. J Clin Sleep Med. 2017 Dec 13. pii: jc-17-00330. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/29246267

Sympathetic nervous system dysfunction in fibromyalgia, chronic fatigue syndrome, irritable bowel syndrome, and interstitial cystitis: a review of case-control studies

Abstract:

BACKGROUND: Fibromyalgia often coexists and overlaps with other syndromes such as chronic fatigue, irritable bowel syndrome, and interstitial cystitis. Chronic stress has been implicated in the pathogenesis of these illnesses. The sympathetic nervous system is a key element of the stress response system. Sympathetic dysfunction has been reported in these syndromes, raising the possibility that such dysautonomia could be their common clustering underlying pathogenesis.

OBJECTIVE: The objective of this study was to carry out a review of all published comparative case-control studies investigating sympathetic nervous system performance in fibromyalgia, chronic fatigue syndrome, irritable bowel syndrome, and interstitial cystitis.

METHODS: Online databases PubMed and EMBASE were accessed using the following key words: autonomic (OR) sympathetic (AND) fibromyalgia, chronic fatigue syndrome, irritable bowel syndrome, and interstitial cystitis. All entries up to December 10th 2012 were reviewed by 2 independent investigators searching for case-control studies in humans. The Method for Evaluating Research and Guidelines Evidence adapted to the Scottish Intercollegiate Guidelines Network was used to rank the level of evidence contained in the selected articles.

RESULTS: A total of 196 articles are included in this review. The most often used methods to assess sympathetic functionality were heart rate variability analysis, sympathetic skin response, tilt table testing, and genetic studies. The majority of studies (65%) described sympathetic nervous system predominance in these overlapping syndromes. In contrast, 7% of the studies found parasympathetic predominance.

CONCLUSIONS: This review demonstrates that sympathetic nervous system predominance is common in fibromyalgia, chronic fatigue syndrome, irritable bowel syndrome, and interstitial cystitis. This concordance raises the possibility that sympathetic dysfunction could be their common underlying pathogenesis that brings on overlapping clinical features. The recognition of sympathetic predominance in these 4 syndromes may have potential clinical implications. It may be worth exploring the use of nonpharmacological measures as well as drug therapies aimed to regain autonomic balance.

 

Source: Martínez-Martínez LA, Mora T, Vargas A, Fuentes-Iniestra M, Martínez-Lavín M. Sympathetic nervous system dysfunction in fibromyalgia, chronic fatigue syndrome, irritable bowel syndrome, and interstitial cystitis: a review of case-control studies. J Clin Rheumatol. 2014 Apr;20(3):146-50. doi: 10.1097/RHU.0000000000000089. https://www.ncbi.nlm.nih.gov/pubmed/24662556

 

Adolescent chronic fatigue syndrome; a follow-up study displays concurrent improvement of circulatory abnormalities and clinical symptoms

Abstract:

BACKGROUND: The pathophysiology of chronic fatigue syndrome (CFS) in adolescents is unknown, and the clinical course and prognosis is still questioned. Recent research indicates that abnormalities of autonomic cardiovascular control may play an important role. The aim of this research project was to perform a follow-up study of adolescents with chronic fatigue syndrome, focusing on clinical symptoms and autonomic cardiovascular control.

METHODS: 47 adolescents (12-18 years old) with CFS were recruited from the outpatient clinic at the Department of Pediatrics, Oslo University Hospital. In a primary visit and a follow-up visit (3-17 months later), we evaluated: a) a wide range of complaints and symptoms and b) cardiovascular variables at baseline and during a 20° head-up tilt-test (HUT).

RESULTS: At the second visit, patients reported significant improvement regarding functional impairments, fatigue severity, muscular pain, concentration problems, post-exertional malaise and the problem of non-relieving rest. Also, at the second visit, baseline heart rate (HR), blood pressure, total peripheral resistance index (TPRI) and LF/HF (low-frequency:high-frequency heart rate variability ratio, an index of sinus node sympathovagal balance derived from spectral analyses of heart rate) were significant lower, and the increases in HR, mean blood pressure (MBP), diastolic blood pressure (DBP) and TPRI during tilt were significantly less pronounced as compared to the first visit. There was a significant correlation between changes in autonomic symptom score, fatigue severity score and functional impairment score from the first to the second visit.

CONCLUSIONS: The majority of adolescents with CFS experienced an improvement over time in functional impairment, self-reported fatigue and additional symptoms, and a concurrent improvement of autonomic cardiovascular control. A possible connection between clinical symptoms and abnormal autonomic control in CFS might represent a focus for further research.

 

Source: Sulheim D, Hurum H, Helland IB, Thaulow E, Wyller VB. Adolescent chronic fatigue syndrome; a follow-up study displays concurrent improvement of circulatory abnormalities and clinical symptoms. Biopsychosoc Med. 2012 Mar 21;6:10. doi: 10.1186/1751-0759-6-10. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3337799/ (Full article)