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Annals of Noninvasive Electrocardiology... Jan 2020Non-linear measures of heart rate variability (HRV) may provide new opportunities to monitor cardiac autonomic regulation during exercise. In healthy individuals, the...
BACKGROUND
Non-linear measures of heart rate variability (HRV) may provide new opportunities to monitor cardiac autonomic regulation during exercise. In healthy individuals, the HRV signal is mainly composed of quasi-periodic oscillations, but it also possesses random fluctuations and so-called fractal structures. One widely applied approach to investigate fractal correlation properties of heart rate (HR) time series is the detrended fluctuation analysis (DFA). DFA is a non-linear method to quantify the fractal scale and the degree of correlation of a time series. Regarding the HRV analysis, it should be noted that the short-term scaling exponent alpha1 of DFA has been used not only to assess cardiovascular risk but also to assess prognosis and predict mortality in clinical settings. It has also been proven to be useful for application in exercise settings including higher exercise intensities, non-stationary data segments, and relatively short recording times.
METHOD
Therefore, the purpose of this systematic review was to analyze studies that investigated the effects of acute dynamic endurance exercise on DFA-alpha1 as a proxy of correlation properties in the HR time series.
RESULTS
The initial search identified 442 articles (351 in PubMed, 91 in Scopus), of which 11 met all inclusion criteria.
CONCLUSIONS
The included studies show that DFA-alpha1 of HRV is suitable for distinguishing between different organismic demands during endurance exercise and may prove helpful to monitor responses to different exercise intensities, movement frequencies, and exercise durations. Additionally, non-linear DFA of HRV is a suitable analytical approach, providing a differentiated and qualitative view of exercise physiology.
Topics: Autonomic Nervous System; Electrocardiography; Exercise; Heart Rate; Humans; Physical Endurance
PubMed: 31498541
DOI: 10.1111/anec.12697 -
World Journal of Clinical Cases Aug 2023It is common for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection to occur in the gastrointestinal tract, which can present itself as an initial...
BACKGROUND
It is common for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection to occur in the gastrointestinal tract, which can present itself as an initial symptom. The severity of coronavirus disease 2019 (COVID-19) is often reflected in the prevalence of gastrointestinal symptoms. COVID-19 can damage the nerve supply to the digestive system, leading to gastrointestinal autonomic dysfunction. There is still much to learn about how COVID-19 affects the autonomic nervous system and the gastrointestinal tract.
AIM
To thoroughly explore the epidemiology and clinical aspects of COVID-19-induced gastrointestinal autonomic dysfunction, including its manifestations, potential mechanisms, diagnosis, differential diagnosis, impact on quality of life, prognosis, and management and prevention strategies.
METHODS
We conducted a thorough systematic search across various databases and performed an extensive literature review. Our review encompassed 113 studies published in English from January 2000 to April 18, 2023.
RESULTS
According to most of the literature, gastrointestinal autonomic dysfunction can seriously affect a patient's quality of life and ultimate prognosis. Numerous factors can influence gastrointestinal autonomic nervous functions. Studies have shown that SARS-CoV-2 has a well-documented affinity for both neural and gastrointestinal tissues, and the virus can produce various gastrointestinal symptoms by reaching neural tissues through different pathways. These symptoms include anorexia, dysgeusia, heartburn, belching, chest pain, regurgitation, vomiting, epigastric burn, diarrhea, abdominal pain, bloating, irregular bowel movements, and constipation. Diarrhea is the most prevalent symptom, followed by anorexia, nausea, vomiting, and abdominal pain. Although COVID-19 vaccination may rarely induce autonomic dysfunction and gastrointestinal symptoms, COVID-19-induced autonomic effects significantly impact the patient's condition, general health, prognosis, and quality of life. Early diagnosis and proper recognition are crucial for improving outcomes. It is important to consider the differential diagnosis, as these symptoms may be induced by diseases other than COVID-19-induced autonomic dysfunction. Treating this dysfunction can be a challenging task.
CONCLUSION
To ensure the best possible outcomes for COVID-19 patients, it is essential to take a multidisciplinary approach involving providing supportive care, treating the underlying infection, managing dysfunction, monitoring for complications, and offering nutritional support. Close monitoring of the patient's condition is crucial, and prompt intervention should be taken if necessary. Furthermore, conducting thorough research on the gastrointestinal autonomic dysfunction caused by COVID-19 is vital to manage it effectively.
PubMed: 37621592
DOI: 10.12998/wjcc.v11.i22.5252 -
Frontiers in Neuroscience 2021Autonomic nervous system (ANS) dysfunction has been suggested to contribute to the high prevalence of cardiovascular complications in individuals with anorexia nervosa...
Autonomic nervous system (ANS) dysfunction has been suggested to contribute to the high prevalence of cardiovascular complications in individuals with anorexia nervosa (AN), yet has not been thoroughly investigated. The current review aimed to synthesize the evidence of basal ANS function in individuals with a current diagnosis of AN and those with a previous diagnosis who had achieved weight restoration, as compared to controls. A systematic review of nine databases was conducted and studies that were published in a peer-review journal, in English, that included at least one assessment of ANS function in individuals with a current or previous diagnosis of AN were selected. Forty-six studies were included with a total of 811 participants with a current diagnosis of AN and 123 participants with a previous diagnosis of AN. ANS function was assessed through heart rate variability ( = 27), orthostatic challenge, blood pressure variability or baroreflex sensitivity ( = 11), adrenergic activity ( = 14), skin conductance level ( = 4), and pupillometry ( = 1). Individuals with AN demonstrated increased parasympathetic activity and decreased sympathetic activity, suggestive of autonomic dysregulation. Following weight restoration, autonomic function trended toward, or was equivalent to, control levels. Autonomic dysregulation is indicated through a range of assessments in individuals with AN. Future investigations should utilize a variety of assessments together in order to conclusively establish the nature of autonomic dysfunction in AN, and following extended weight restoration. Moreover, investigation into the co-occurrence of ANS function and cardiovascular risk is required.
PubMed: 34262430
DOI: 10.3389/fnins.2021.682208 -
The Cochrane Database of Systematic... Oct 2017This is an updated version of the original Cochrane Review published in the Cochrane Library, Issue 5, 2015.Yoga may induce relaxation and stress reduction, and... (Review)
Review
BACKGROUND
This is an updated version of the original Cochrane Review published in the Cochrane Library, Issue 5, 2015.Yoga may induce relaxation and stress reduction, and influence the electroencephalogram and the autonomic nervous system, thereby controlling seizures. Yoga would be an attractive therapeutic option for epilepsy if proved effective.
OBJECTIVES
To assess whether people with epilepsy treated with yoga:(a) have a greater probability of becoming seizure free;(b) have a significant reduction in the frequency or duration of seizures, or both; and(c) have a better quality of life.
SEARCH METHODS
For this update, we searched the Cochrane Epilepsy Group Specialized Register (3 January 2017), the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 12) in the Cochrane Library (searched 3 January 2017), MEDLINE (Ovid, 1946 to 3 January 2017), SCOPUS (1823 to 3 January 2017), ClinicalTrials.gov (searched 3 January 2017), the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (searched 3 January 2017), and also registries of the Yoga Biomedical Trust and the Research Council for Complementary Medicine. In addition, we searched the references of all the identified studies. No language restrictions were imposed.
SELECTION CRITERIA
The following study designs were eligible for inclusion: randomised controlled trials (RCT) of treatment of epilepsy with yoga. The studies could be double-, single- or unblinded. Eligible participants were adults with uncontrolled epilepsy comparing yoga with no treatment or different behavioural treatments.
DATA COLLECTION AND ANALYSIS
Two review authors independently assessed the trials for inclusion and extracted data. The following outcomes were assessed: (a) percentage of people rendered seizure free; (b) seizure frequency and duration; (c) quality of life. Analyses were on an intention-to-treat basis. Odds ratio (OR) with 95% confidence intervals (95% Cls) were estimated for the outcomes.
MAIN RESULTS
We did not identify any new studies for this update, therefore the results are unchanged.For the previous version of the review, the authors found two unblinded trials in people with refractory epilepsy. In total these two studies included 50 people (18 treated with yoga and 32 to control interventions). Antiepileptic drugs were continued in all the participants. Baseline phase lasted three months in both studies and treatment phase from five weeks to six months in the two trials. Randomisation was by roll of a die in one study and using a computerised randomisation table in the other one but neither study provided details of concealment of allocation and were rated as unclear risk of bias. Overall, the two studies were rated as low risk of bias (all participants were included in the analysis; all expected and pre-expected outcomes were reported; no other sources of bias).The overall ORs with 95% CI were as follows: (i) seizure free for six months - for yoga versus sham yoga the OR was 14.54 (95% CI 0.67 to 316.69) and for yoga versus 'no treatment' group it was 17.31 (95% CI 0.80 to 373.45); for Acceptance and Commitment Therapy (ACT) versus yoga the OR was 1.00 (95% Cl 0.16 to 6.42); (ii) reduction in seizure frequency - the mean difference between yoga versus sham yoga group was -2.10 (95% CI -3.15 to -1.05) and for yoga versus 'no treatment' group it was -1.10 (95% CI -1.80 to -0.40); (iii) more than 50% reduction in seizure frequency - for yoga versus sham yoga group, OR was 81.00 (95% CI 4.36 to 1504.46) and for the yoga versus 'no treatment' group it was 158.33 (95% CI 5.78 to 4335.63); ACT versus yoga OR was 0.78 (95% Cl 0.04 to 14.75); (iv) more than 50% reduction in seizure duration - for yoga versus sham yoga group OR was 45.00 (95% CI 2.01 to 1006.75) and for yoga versus 'no treatment' group it was 53.57 (95% CI 2.42 to 1187.26); ACT versus yoga OR was 0.67 (95% Cl 0.10 to 4.35).In addition in Panjwani 1996 the authors reported that the one-way analysis of variance revealed no statistically significant differences between the three groups. A P-Lambda test taking into account the P values between the three groups also indicated that the duration of epilepsy in the three groups was not comparable. No data were available regarding quality of life. In Lundgren 2008 the authors reported that there was no significant difference between the yoga and ACT groups in seizure-free rates, 50% or greater reduction in seizure frequency or seizure duration at one-year follow-up. The yoga group showed significant improvement in their quality of life according to the Satisfaction With Life Scale (SWLS) (P < 0.05), while the ACT group had significant improvement in the World Health Organization Quality of Life-BREF (WHOQOL-BREF) scale (P < 0.01).Overall, we assessed the quality of evidence as low; no reliable conclusions can be drawn at present regarding the efficacy of yoga as a treatment for epilepsy.
AUTHORS' CONCLUSIONS
A study of 50 subjects with epilepsy from two trials reveals a possible beneficial effect in control of seizures. Results of the overall efficacy analysis show that yoga treatment was better when compared with no intervention or interventions other than yoga (postural exercises mimicking yoga). There was no difference between yoga and Acceptance and Commitment Therapy. However no reliable conclusions can be drawn regarding the efficacy of yoga as a treatment for uncontrolled epilepsy, in view of methodological deficiencies such as limited number of studies, limited number of participants randomised to yoga, lack of blinding and limited data on quality-of-life outcome. Physician blinding would normally be taken to be the person delivering the intervention, whereas we think the 'physician' would in fact be the outcome assessor (who could be blinded), so that would be a reduction in detection bias rather than performance bias. In addition, evidence to inform outcomes is limited and of low quality. Further high-quality research is needed to fully evaluate the efficacy of yoga for refractory epilepsy.Since we did not find any new studies, our conclusions remain unchanged.
Topics: Acceptance and Commitment Therapy; Adult; Drug Resistant Epilepsy; Humans; Quality of Life; Randomized Controlled Trials as Topic; Seizures; Stress, Psychological; Yoga
PubMed: 28982217
DOI: 10.1002/14651858.CD001524.pub3 -
NeuroRehabilitation 2018Recent evidence suggests that autonomic nervous dysfunction may be one of many potential factors contributing to persisting post-concussion symptoms. (Review)
Review
BACKGROUND
Recent evidence suggests that autonomic nervous dysfunction may be one of many potential factors contributing to persisting post-concussion symptoms.
OBJECTIVE
This is the first systematic review to explore the impact of concussion on multiple aspects of autonomic nervous system functioning.
METHODS
The methods employed are in compliance with the American Academy of Neurology (AAN) and PRISMA standards. Embase, MEDLINE, PsychINFO, and Science Citation Index literature searches were performed using relevant indexing terms for articles published prior to the end of December 2016. Data extraction was performed by two independent groups, including study quality indicators to determine potential risk for bias according to the 4-tiered classification scheme of the AAN.
RESULTS
Thirty-six articles qualified for inclusion in the analysis. Only three studies (one Class II and two Class IV) did not identify anomalies in measures of ANS functioning in concussed populations.
CONCLUSIONS
The evidence supports the conclusion that it is likely that concussion causes autonomic nervous system anomalies. An awareness of this relationship increases our understanding of the physical impact of concussion, partially explains the overlap of concussion symptoms with other medical conditions, presents opportunities for further research, and has the potential to powerfully inform treatment decisions.
Topics: Autonomic Nervous System; Humans; Post-Concussion Syndrome
PubMed: 29660949
DOI: 10.3233/NRE-172298 -
The Journal of the Canadian... Dec 2023To identify, appraise and synthesize the evidence of autonomic nervous system (ANS) dysfunction following sport-related concussion in pediatric populations.
OBJECTIVE
To identify, appraise and synthesize the evidence of autonomic nervous system (ANS) dysfunction following sport-related concussion in pediatric populations.
METHODS
A literature search was conducted using MEDLINE (Ovid), SportDiscus (EBSCO), CINAHL (EBSCO), EMBASE (Ovid) and PsycINFO (Ovid). Studies were selected and appraised using the Joanna Briggs Institute (JBI) critical appraisal tools. Data was extracted from the included studies and qualitatively synthesized.
RESULTS
Eleven studies were included in the synthesis. There was variability in the methods used to measure ANS function between studies, and sample populations and time to assessment following concussion varied considerably. There was also variability in the direction of change of ANS function between some studies.
CONCLUSION
This systematic review identifies that concussion is associated with dysregulation of ANS function in pediatric athletes. We identified some weaknesses in the extant literature which may be due to existing logistical and financial barriers to implementing valid ANS measurements in clinical and sports settings.
PubMed: 38283159
DOI: No ID Found -
Revista Brasileira de Terapia Intensiva 2017To present a systematic review of the use of autonomic nervous system monitoring as a prognostic tool in intensive care units by assessing heart rate variability. (Review)
Review
OBJECTIVE
To present a systematic review of the use of autonomic nervous system monitoring as a prognostic tool in intensive care units by assessing heart rate variability.
METHODS
Literature review of studies published until July 2016 listed in PubMed/Medline and conducted in intensive care units, on autonomic nervous system monitoring, via analysis of heart rate variability as a prognostic tool (mortality study). The following English terms were entered in the search field: ("autonomic nervous system" OR "heart rate variability") AND ("intensive care" OR "critical care" OR "emergency care" OR "ICU") AND ("prognosis" OR "prognoses" OR "mortality").
RESULTS
There was an increased likelihood of death in patients who had a decrease in heart rate variability as analyzed via heart rate variance, cardiac uncoupling, heart rate volatility, integer heart rate variability, standard deviation of NN intervals, root mean square of successive differences, total power, low frequency, very low frequency, low frequency/high frequency ratio, ratio of short-term to long-term fractal exponents, Shannon entropy, multiscale entropy and approximate entropy.
CONCLUSION
In patients admitted to intensive care units, regardless of the pathology, heart rate variability varies inversely with clinical severity and prognosis.
Topics: Autonomic Nervous System; Critical Care; Heart Rate; Humans; Intensive Care Units; Monitoring, Physiologic; Prognosis; Severity of Illness Index
PubMed: 29340538
DOI: 10.5935/0103-507X.20170072 -
Epilepsia Mar 2017To comprehensively analyze ictal asystole (IA) on a large number of subjects. (Review)
Review
OBJECTIVE
To comprehensively analyze ictal asystole (IA) on a large number of subjects.
METHODS
We performed a systematic review of case report studies of patients diagnosed with IA (1983-2016). Each included case was characterized with respect to patient history, IA seizure characteristics, diagnostic workup, and therapy. In addition, comparative analyses were also carried out: two alignments were developed based on the delay between epilepsy onset and IA onset ("new-onset" if <1 year, "late-onset" if ≥1 year) and asystole duration (asystole was "very prolonged" if lasted >30 s).
RESULTS
One hundred fifty-seven cases were included. All patients had focal epilepsy. In 7% of cases IA developed during a secondary generalized tonic-clonic seizure. Both the seizure-onset zone and the focal seizure activity at asystole beginning were usually temporal (p < 0.001 and p = 0.001, respectively) and were lateralized to the left hemisphere in 62% (p = 0.005 and p = 0.05, respectively). Asystole duration was 18 ± 14 s (mean±SD) (range 3-96 s); 73% of patients had late-onset, 27% had new-onset IA. Compared to late-onset IA, new-onset IA was associated with female gender (p = 0.023), preexisting heart condition (p = 0.014), focal seizure activity at asystole beginning (p = 0.012), normal neuroimaging (p = 0.013), normal interictal EEG (p < 0.001), auditory aura (p = 0.012), and drug-responsive epilepsy (p < 0.001). "Very prolonged" asystole was associated with secondary generalized tonic-clonic seizures (p = 0.003) and tended to occur in extratemporal lobe seizures (p = 0.074). No IA-related death was reported.
SIGNIFICANCE
Characteristics considered to be typical of IA (focal, left temporal seizures appearing on grounds of a long-lasting, intractable epilepsy) seem only partially legitimate. We suggest that in new-onset IA, female gender and a preexisting heart condition could serve as predispositions in an otherwise benign epilepsy. We speculate that in late-onset IA, male-predominant changes in neuronal networks in chronic, intractable epilepsy and an accompanying autonomic dysregulation serve as facilitating factors.
Topics: Adolescent; Adult; Age of Onset; Aged; Child; Child, Preschool; Databases, Bibliographic; Electroencephalography; Female; Functional Laterality; Heart Arrest; Humans; Infant; Male; Middle Aged; Seizures; Young Adult
PubMed: 27988965
DOI: 10.1111/epi.13644 -
Frontiers in Human Neuroscience 2016Recent developments in stress theory have emphasized the significance of perseverative cognition (worry and rumination) in furthering our understanding of stress-disease... (Review)
Review
Recent developments in stress theory have emphasized the significance of perseverative cognition (worry and rumination) in furthering our understanding of stress-disease relationships. Substantial evidence has shown that perseverative cognition (PC) is associated with somatic outcomes and numerous physiological concomitants have been identified (i.e., cardiovascular, autonomic, and endocrine nervous system activity parameters). However, there has been no synthesis of the evidence regarding the association between PC and health behaviors. This is important given such behaviors may also directly and/or indirectly influence health and disease outcomes (triggered by PC). Therefore, the aim of the current review was to synthesize available studies that have explored the relationship between worry and rumination and health behaviors (health risk: behaviors which, if performed, would be detrimental to health; health promoting: behaviors which, if performed, would be beneficial for health). A systematic review and meta-analyses of the literature were conducted. Studies were included in the review if they reported the association between PC and health behavior. Studies identified in MEDLINE or PsycINFO ( = 7504) were screened, of which 19 studies met the eligibility criteria. Random-effects meta-analyses suggested increased PC was generally associated with increased health risk behaviors but not health promoting behaviors. Further analyses indicated that increases in rumination ( = 0.122), but not reflection ( = -0.080), or worry ( = 0.048) were associated with health risk behaviors. In conclusion, these results showed that increases in PC are associated with increases in health risk behaviors (substance use, alcohol consumption, unhealthy eating, and smoking) that are driven primarily through rumination. These findings provide partial support for our hypothesis that in Brosschot et al.'s (2006) original perseverative cognition hypothesis, there may be scope for additional routes to pathogenic disease via poorer health behaviors.
PubMed: 27877119
DOI: 10.3389/fnhum.2016.00534 -
Journal of Clinical Medicine Jul 2022Although autonomic dysfunction (AD) after the recovery from Coronavirus disease 2019 (COVID-19) has been thoroughly described, few data are available regarding the... (Review)
Review
Although autonomic dysfunction (AD) after the recovery from Coronavirus disease 2019 (COVID-19) has been thoroughly described, few data are available regarding the involvement of the autonomic nervous system (ANS) during the acute phase of SARS-CoV-2 infection. The primary aim of this review was to summarize current knowledge regarding the AD occurring during acute COVID-19. Secondarily, we aimed to clarify the prognostic value of ANS involvement and the role of autonomic parameters in predicting SARS-CoV-2 infection. According to the PRISMA guidelines, we performed a systematic review across Scopus and PubMed databases, resulting in 1585 records. The records check and the analysis of included reports' references allowed us to include 22 articles. The studies were widely heterogeneous for study population, dysautonomia assessment, and COVID-19 severity. Heart rate variability was the tool most frequently chosen to analyze autonomic parameters, followed by automated pupillometry. Most studies found ANS involvement during acute COVID-19, and AD was often related to a worse outcome. Further studies are needed to clarify the role of autonomic parameters in predicting SARS-CoV-2 infection. The evidence emerging from this review suggests that a complex autonomic nervous system imbalance is a prominent feature of acute COVID-19, often leading to a poor prognosis.
PubMed: 35807167
DOI: 10.3390/jcm11133883