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Journal of Clinical Medicine Jan 2024Heart rate variability (HRV) is a reliable and convenient method to assess autonomic function. Cross-sectional studies have established a link between HRV and cognition.... (Review)
Review
BACKGROUND
Heart rate variability (HRV) is a reliable and convenient method to assess autonomic function. Cross-sectional studies have established a link between HRV and cognition. Longitudinal studies are an emerging area of research with important clinical implications in terms of the predictive value of HRV for future cognition and in terms of the potential causal relationship between HRV and cognition. However, they have not yet been the objective of a systematic review. Therefore, the aim of this systematic review was to investigate the association between HRV and cognition in longitudinal studies.
METHODS
The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The Embase, PsycINFO and PubMed databases were searched from the earliest available date to 26 June 2023. Studies were included if they involved adult human subjects and evaluated the longitudinal association between HRV and cognition. The risk of bias was assessed with the Newcastle-Ottawa Scale for Cohort Studies. The results were presented narratively.
RESULTS
Of 14,359 records screened, 12 studies were included in this systematic review, with a total of 24,390 participants. Two thirds of the studies were published from 2020 onwards. All studies found a longitudinal relationship between HRV and cognition. There was a consistent association between higher parasympathetic nervous system (PNS) activity and better cognition, and some association between higher sympathetic nervous system activity and worse cognition. Also, higher PNS activity persistently predicted better executive functioning, while data on episodic memory and language were more scant and/or controversial.
CONCLUSIONS
Our results support the role of HRV as a biomarker of future cognition and, potentially, as a therapeutic target to improve cognition. They will need confirmation by further, more comprehensive studies also including unequivocal non-HRV sympathetic measures and meta-analyses.
PubMed: 38202287
DOI: 10.3390/jcm13010280 -
Advanced Biomedical Research 2023Physical therapies such as electroconvulsive therapy (ECT) may result in higher response and recovery rates, especially in patients who have treatment-resistant... (Review)
Review
Physical therapies such as electroconvulsive therapy (ECT) may result in higher response and recovery rates, especially in patients who have treatment-resistant depression. Various studies have reported different changes in heart rate variability (HRV) parameters before and after depression treatment with ECT. Therefore, the present study reviews systematically the evidence describing changes in HRV parameters and the cardiac autonomic nervous system associated with ECT. Scopus, Web of Science, PubMed, and Embase electronic databases were searched for papers published up to September 8, 2022, without any restriction on the year and language of the study. A total of 895 articles were reviewed by two independent groups and nine articles that met the inclusion criteria were selected. Time-domain and frequency-domain HRV parameters were assessed. In conclusion, the results of our systematic review provided limited evidence for the influence of ECT on HRV parameters. Despite studies suggesting depression results in a decrease in parasympathetic activity and ECT results in an increase in cardiac vagal activity, ECT seems to have no consistent effect on HRV parameters.
PubMed: 38073723
DOI: 10.4103/abr.abr_95_23 -
Annals of Medicine 2023Cardiac sympathetic hyperinnervation after myocardial infarction (MI) is associated with arrhythmogenesis and sudden cardiac death. The characteristics of cardiac... (Review)
Review
BACKGROUND
Cardiac sympathetic hyperinnervation after myocardial infarction (MI) is associated with arrhythmogenesis and sudden cardiac death. The characteristics of cardiac sympathetic hyperinnervation remain underexposed.
OBJECTIVE
To provide a systematic review on cardiac sympathetic hyperinnervation after MI, taking into account: (1) definition, experimental model and quantification method and (2) location, amount and timing, in order to obtain an overview of current knowledge and to expose gaps in literature.
METHODS
References on cardiac sympathetic hyperinnervation were screened for inclusion. The included studies received a full-text review and quality appraisal. Relevant data on hyperinnervation were collected and qualitatively analysed.
RESULTS
Our literature search identified 60 eligible studies performed between 2000 and 2022. Cardiac hyperinnervation is generally defined as an increased sympathetic nerve density or increased number of nerves compared to another control group (100%). Studies were performed in a multitude of experimental models, but most commonly in male rats with permanent left anterior descending (LAD) artery ligation (male: 63%, rat: 68%, permanent ligation: 93%, LAD: 97%). Hyperinnervation seems to occur mainly in the borderzone. Quantification after MI was performed in regions of interest in µm/mm (41%) or in percentage of nerve fibres (46%) and the reported amount showed a great variation ranging from 439 to 126,718 µm/mm. Hyperinnervation seems to start from three days onwards to >3 months without an evident peak, although studies on structural evaluation over time and in the chronic phase were scarce.
CONCLUSIONS
Cardiac sympathetic hyperinnervation after MI occurs mainly in the borderzone from three days onwards and remains present at later timepoints, for at least 3 months. It is most commonly studied in male rats with permanent LAD ligation. The amount of hyperinnervation differs greatly between studies, possibly due to differential quantification methods. Further studies are required that evaluate cardiac sympathetic hyperinnervation over time and in the chronic phase, in transmural sections, in the female sex, and in MI with reperfusion.
Topics: Male; Female; Rats; Humans; Animals; Heart; Myocardial Infarction; Arrhythmias, Cardiac; Sympathetic Nervous System; Death, Sudden, Cardiac
PubMed: 38065671
DOI: 10.1080/07853890.2023.2283195 -
Biological Psychology Jan 2024Fatigue-specific changes in the autonomic nervous system are often assumed to underlie the development of mental fatigue caused by prolonged cognitive tasks (i.e....
Fatigue-specific changes in the autonomic nervous system are often assumed to underlie the development of mental fatigue caused by prolonged cognitive tasks (i.e. Time-on-Task). Therefore, several previous studies have chosen to investigate the Time-on-Task related changes in heart rate variability (HRV). However, previous studies have used many different HRV indices, and their results often show inconsistencies. The present study, therefore, systematically reviewed previous empirical HRV studies with healthy individuals and in which mental fatigue is induced by prolonged cognitive tasks. Articles relevant to the objectives were systematically searched and selected by applying the PRISMA guidelines. We screened 360 records found on 4 databases and found that 19 studies were eligible for full review in accordance with the inclusion criteria. In general, all studies reviewed (with the exception of two studies) found significant changes in HRV with increasing Time-on-Task, suggesting that HRV is a reliable autonomic marker for Time-on-Task induced fatigue. The most conclusive HRV indices that showed a consistent Time-on-Task effect were the low frequency component of HRV and the time domain indices, particularly the root mean square of successive differences. Time-on-Task typically induced an increasing trend in both type of measures.
Topics: Humans; Autonomic Nervous System; Heart Rate; Mental Fatigue
PubMed: 38056707
DOI: 10.1016/j.biopsycho.2023.108727 -
International Journal of Stem Cells Nov 2023Spinal cord injury (SCI) is a serious nervous system disease that usually leads to the impairment of the motor, sensory, and autonomic nervous functions of the spinal... (Review)
Review
Spinal cord injury (SCI) is a serious nervous system disease that usually leads to the impairment of the motor, sensory, and autonomic nervous functions of the spinal cord, and it places a heavy burden on families and healthcare systems every year. Due to the complex pathophysiological mechanism of SCI and the poor ability of neurons to regenerate, the current treatment scheme has very limited effects on the recovery of spinal cord function. In addition, due to their unique advantages, exosomes can be used as carriers for cargo transport. In recent years, some studies have confirmed that treatment with mesenchymal stem cells (MSCs) can promote the recovery of SCI nerve function. The therapeutic effect of MSCs is mainly related to exosomes secreted by MSCs, and exosomes may have great potential in SCI therapy. In this review, we summarized the repair mechanism of mesenchymal stem cells-derived exosomes (MSCs-Exos) in SCI treatment and discussed the microRNAs related to SCI treatment based on MSCs-Exos and their mechanism of action, which is helpful to further understand the role of exosomes in SCI.
PubMed: 38016704
DOI: 10.15283/ijsc23092 -
Scientific Reports Nov 2023Psychological factors may have a precipitant role in takotsubo syndrome (TS). Aberrant Heart Rate Variability (HRV) has been reported in TS, suggesting inflexibility of... (Meta-Analysis)
Meta-Analysis
Psychological factors may have a precipitant role in takotsubo syndrome (TS). Aberrant Heart Rate Variability (HRV) has been reported in TS, suggesting inflexibility of the autonomous nervous system. Nevertheless, results on HRV alterations and their link with psychological factors in TS are conflicting. This work aimed to systematically explore whether TS may be associated with HRV alterations and their association with specific psychological profiles in TS patients. A literature search was conducted across databases (Pubmed, Scopus, PsycInfo, Web of Science) and empirical studies including TS patients which were evaluated in one or more HRV indices were retrieved. HRV and psychological outcomes were extracted. 10 empirical studies with 194 TS patients were included. Results showed significant alteration of HRV in TS patients, with indices compared to controls, and a progressive increase over time. Nevertheless, retrieved data presented mixed results, as also shown by a large heterogeneity in the meta-analytic findings. 2 studies found significant relationships between HRV alterations and trait-rather than state-psychological outcomes (i.e., coping strategies and emotional arousal), pointing to the need to explore the role of psychological vulnerabilities, rather than single traumatic stressors, in the association between HRV and TS.
Topics: Humans; Heart Rate; Takotsubo Cardiomyopathy; Autonomic Nervous System; Adaptation, Psychological; Emotions
PubMed: 38007581
DOI: 10.1038/s41598-023-47982-0 -
Nutrients Oct 2023A systematic review was undertaken to investigate the involvement of hydration in heart rate (HR), HR variability (HRV) and diastolic (DBP) and systolic (SBP) blood... (Meta-Analysis)
Meta-Analysis Review
Influence of Fluid Ingestion on Heart Rate, Cardiac Autonomic Modulation and Blood Pressure in Response to Physical Exercise: A Systematic Review with Meta-Analysis and Meta-Regression.
A systematic review was undertaken to investigate the involvement of hydration in heart rate (HR), HR variability (HRV) and diastolic (DBP) and systolic (SBP) blood pressure in response to exercise. Data synthesis: The EMBASE, MEDLINE, Cochrane Library, CINAHL, LILACS and Web of Science databases were searched. In total, 977 studies were recognized, but only 36 were included after final screening (33 studies in meta-analysis). This study includes randomized controlled trials (RCTs) and non-RCTs with subjects > 18 years old. The hydration group consumed water or isotonic drinks, while the control group did not ingest liquids. For the hydration protocol (before, during and after exercise), the HR values during the exercise were lower compared to the controls (-6.20 bpm, 95%CI: -8.69; -3.71). In the subgroup analysis, "water ingested before and during exercise" showed lower increases in HR during exercise (-6.20, 95%CI: 11.70 to -0.71), as did "water was ingested only during exercise" (-6.12, 95%CI: -9.35 to -2.89). Water intake during exercise only revealed a trend of avoiding greater increases in HR during exercise (-4,60, 95%CI: -9.41 to 0.22), although these values were not significantly different ( = 0.06) from those of the control. "Isotonic intake during exercise" showed lower HRs than the control (-7.23 bpm, 95% CI: -11.68 to -2.79). The HRV values following the exercise were higher in the hydration protocol (SMD = 0.48, 95%CI: 0.30 to 0.67). The values of the SBP were higher than those of the controls (2.25 mmHg, 95%CI: 0.08 to 4.42). Conclusions: Hydration-attenuated exercise-induced increases in HR during exercise, improved autonomic recovery via the acceleration of cardiac vagal modulation in response to exercise and caused a modest increase in SBP values, but did not exert effects on DBP following exercise.
Topics: Humans; Adolescent; Blood Pressure; Heart Rate; Exercise; Water; Eating; Randomized Controlled Trials as Topic
PubMed: 37960187
DOI: 10.3390/nu15214534 -
Revista Paulista de Pediatria : Orgao... 2023To evaluate the relationship between birth weight and the autonomic nervous system in adulthood through a systematic review. (Review)
Review
OBJECTIVE
To evaluate the relationship between birth weight and the autonomic nervous system in adulthood through a systematic review.
DATA SOURCE
This is a systematic review of publications without limitation of year and language. We included studies involving the autonomic nervous system and birth weight in adults. Manuscripts were selected based on electronic searches of Medical Literature Analysis and Retrieval System Online (MEDLINE), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Web of Science Cochrane Library and Scopus databases, using "Autonomic Nervous System" OR "Heart Rate" OR "Heart Rate Variability" AND "Birth Weight" as a search strategy. This review is registered on the International Prospective Register of Systematic Reviews - PROSPERO (ID: CRD42020165622).
DATA SYNTHESIS
We found 894 articles; 215 were excluded for duplicity. Of the remaining 679 studies, 11 remained. Two were excluded because they did not specifically treat the autonomic nervous system or birth weight. There were nine publications, two cohort and seven cross-sectional studies. The main findings were that extreme, very low, low or high birth weight may have some impact on the autonomic nervous system in adult life.
CONCLUSIONS
Birth weight outside the normality rate may have a negative influence on the autonomic nervous system, causing autonomic dysfunction and increasing the risk of cardiovascular diseases in adult life. Thus, the importance of the follow-up of health professionals from pregnancy to gestation and throughout life, with preventive care being emphasized.
Topics: Adult; Female; Humans; Pregnancy; Autonomic Nervous System; Birth Weight; Cardiovascular Diseases; Cross-Sectional Studies; Systematic Reviews as Topic
PubMed: 37937677
DOI: 10.1590/1984-0462/2024/42/2023002 -
The International Journal of... Mar 2024The discovery of effective treatments for major depressive disorder (MDD) may help target different brain pathways. Invasive vagus nerve stimulation (VNS) is an...
BACKGROUND
The discovery of effective treatments for major depressive disorder (MDD) may help target different brain pathways. Invasive vagus nerve stimulation (VNS) is an effective neuromodulation technique for the treatment of MDD; however, the effectiveness of the noninvasive technique, transauricular VNS (taVNS), remains unknown. Moreover, a mechanistic understanding of the neural effects behind its biological and therapeutic effects is lacking. This review aimed to evaluate the clinical evidence and the neural and anti-inflammatory effects of taVNS in MDD.
METHODS
Two searches were conducted using a systematic search strategy reviewed the clinical efficacy and neural connectivity of taVNS in MDD in humans and evaluated the changes in inflammatory markers after taVNS in humans or animal models of depression. A risk of bias assessment was performed in all human studies.
RESULTS
Only 5 studies evaluated the effects of taVNS in patients with depression. Although the studies demonstrated the efficacy of taVNS in treating depression, they used heterogeneous methodologies and limited data, thus preventing the conduct of pooled quantitative analyses. Pooled analysis could not be performed for studies that investigated the modulation of connectivity between brain areas; of the 6 publications, 5 were based on the same experiment. The animal studies that analyzed the presence of inflammatory markers showed a reduction in the level of pro-inflammatory cytokines or receptor expression.
CONCLUSIONS
Data on the clinical efficacy of taVNS in the treatment of MDD are limited. Although these studies showed positive results, no conclusions can be drawn regarding this topic considering the heterogeneity of these studies, as in the case of functional connectivity studies. Based on animal studies, the application of taVNS causes a decrease in the level of inflammatory factors in different parts of the brain, which also regulate the immune system. Therefore, further studies are needed to understand the effects of taVNS in patients with MDD.
Topics: Animals; Humans; Depressive Disorder, Major; Vagus Nerve Stimulation; Brain; Treatment Outcome; Vagus Nerve
PubMed: 37870480
DOI: 10.1093/ijnp/pyad058 -
Healthcare (Basel, Switzerland) Oct 2023Diabetic neuropathy, including autonomic neuropathy, is a severe complication in patients with poorly controlled diabetes. Specifically, cardiovascular autonomic... (Review)
Review
BACKGROUND
Diabetic neuropathy, including autonomic neuropathy, is a severe complication in patients with poorly controlled diabetes. Specifically, cardiovascular autonomic neuropathy (CAN) plays a significant prognostic role in cardiovascular morbidity and mortality. Exercise, an essential component of diabetes treatment, may have a therapeutic effect on patients with diabetes complicated by CAN. However, it remains unclear whether exercise has a therapeutic or protective effect in diabetes patients with CAN.
METHODS
The author conducted a systematic search of PubMed/MEDLINE, Embase, and The Cochrane Library, resulting in the identification of eight eligible randomized controlled trials for this review.
RESULTS
Exercise, including aerobic exercise combined with resistance training (RT), high-intensity interval training, and progressive RT, has shown a beneficial effect on cardiac autonomic function (CAF) in patients with type 2 diabetes, as measured by heart rate variability, heart rate recovery, and baroreflex sensitivity. However, most studies had low quality. Moreover, there were no relevant studies examining the effect of exercise on CAF in older patients, patients with poorly controlled diabetes, and patients with type 1 diabetes.
CONCLUSIONS
Exercise has the potential to manage patients with CAN by balancing sympathetic and parasympathetic nervous system functions; however, further studies are warranted in the future.
PubMed: 37830705
DOI: 10.3390/healthcare11192668