AGING, HEART RATE VARIABILITY AND METABOLIC IMPACT OF OBESITY

Compression therapy, autonomic nervous system, and heart rate variability: A narrative review and our preliminary personal experience

Aims

To highlight the relationship among compression therapy (CT), the autonomic nervous system (ANS) (parasympathetic and sympathetic system), and the heart rate variability (HRV) analysis.

Background

Beyond the typical analgesic and anti-inflammatory effects of CT in patients affected by venous and/or lymphatic diseases, some literature about CT influence on wellbeing has been published as well. More specifically, CT influence on the ANS has been elucidated mostly through HRV application, providing useful quali-quantitative data for scientific and clinical purposes.

Material and Methods

A literature search was performed through several web-based search engines to investigate the available evidence concerning the possible influence of CT on the ANS and on psychoneuroendocrineimmunology. Moreover, we examined literature data regarding HRV use in the assessment of CT. Lastly, a preliminary cross-over study was performed on 10 patients affected by phlebolymphedema of the lower limbs, undergoing CT with 18–21 mmHg stockings for 10 h and investigated by means of HRV.

Results

A CT-based increase of the anti-inflammatory activity of the parasympathetic (vagal) system has been elucidated in most scientific literature. Similarly, CT application has generally resulted in an improvement of HRV, which indicates a beneficial influence on the ANS. In our preliminary experience with compression stockings and HRV, two parasympathetic-based parameters improved by 22.8% and 68.0% after 10 h, whereas they decreased in the same subjects without stockings by 2.7% and 8.2%, during normal breathing. The remaining HRV parameters did not show relevant variations, especially during diaphragmatic breathing.

Conclusions

From literature data and based on our very preliminary experience, it is possible to deduce that CT exerts different effects on the psychobiological parameters of the individual, overall improving HRV and parasympathetic activity. Incorporating both HRV/ANS assessment in phlebolymphology and the beneficial neural action of CT in health care may represent viable options in the future biomedical science.

Сardiorespiratory relationships in people of young age depending on the composite composition of the body

BACKGROUND: The decisive importance of the sympathetic and parasympathetic nervous system in maintaining vegetative homeostasis requires the determination of sensitive non-invasive parameters of multidimensional outpatient monitoring of cardiorespiratory adaptation under various physiological and clinical conditions, taking into account the function of external respiration (FER), compound body composition and heart rate variability (HRV).

AIM: To identify concomitant changes in HRV, HR and compound body composition in young people as markers of cardiorespiratory adaptation and rehabilitation.

MATERIALS AND METHODS: On the basis of the Kuban State Medical University, a single-centre, interventional, cross-sectional, single-sample, comparative, uncontrolled study of a general group of young people in which respiratory parameters and parameters of the compound body composition were determined. Some individuals in this group additionally underwent Holter monitoring of the electrocardiogram (ECG) at short intervals.

RESULTS: In young people, a change in the compound body composition with an increase in total fat mass, visceral and body fat is associated with a decrease in respiratory function (a decrease in the Tiffno index, a decrease in the maximum middle-expiratory flow — MMEF), manifested by a decrease in HRV (according to the TI indicator), the absence of an increase in the autonomic regulation circuit (according to SDNN indicator), a decrease in parasympathetic activity (in terms of rMSSD) and the absence of sympathetic activation (in terms of SDANN). Positive shifts in the form of an increase in trunk muscles, the total amount of water and a decrease in the total fat mass are accompanied by an increase in lung capacity, forced expiratory volume in the first second and a change in HRV with sympathetic (in terms of LF / HF, SDANN) and parasympathetic activation (in terms of rMSSD), an increase in HRV (in terms of TI) and an increase in the autonomic regulation circuit of the vegetative nervous system (in terms of SDNN).

CONCLUSION: Accurate and rapid diagnostics of vegetative homeostasis requires a comprehensive correlative analysis of the parameters characterizing HRV in short recordings, the compound composition of the human body and respiratory function.

Role of Body Mass and Physical Activity in Autonomic Function Modulation on Post-COVID-19 Condition: An Observational Subanalysis of Fit-COVID Study

The harmful effects of coronavirus disease 2019 (COVID-19) can reach the autonomic nervous system (ANS) and endothelial function. Therefore, the detrimental multiorgan effects of COVID-19 could be induced by deregulations in ANS that may persist after the acute SARS-CoV-2 infection. Additionally, investigating the differences in ANS response in overweight/obese, and physically inactive participants who had COVID-19 compared to those who did not have the disease is necessary. The aim of the study was to analyze the autonomic function of young adults after mild-to-moderate infection with SARS-CoV-2 and to assess whether body mass index (BMI) and levels of physical activity modulates autonomic function in participants with and without COVID-19. Patients previously infected with SARS-CoV-2 and healthy controls were recruited for this cross-sectional observational study. A general anamnesis was taken, and BMI and physical activity levels were assessed. The ANS was evaluated through heart rate variability. A total of 57 subjects were evaluated. Sympathetic nervous system activity in the post-COVID-19 group was increased (stress index; p = 0.0273). They also presented lower values of parasympathetic activity (p < 0.05). Overweight/obese subjects in the post-COVID-19 group presented significantly lower parasympathetic activity and reduced global variability compared to non-obese in control group (p < 0.05). Physically inactive subjects in the post-COVID-19 group presented significantly higher sympathetic activity than active subjects in the control group. Parasympathetic activity was significantly increased in physically active subjects in the control group compared to the physically inactive post-COVID-19 group (p < 0.05). COVID-19 promotes changes in the ANS of young adults, and these changes are modulated by overweight/obesity and physical activity levels.

Cardiac Autonomic Modulation Response Before, During, and After Submaximal Exercise in Older Adults With Intellectual Disability

The analysis of the heart rate variability (HRV) consists of changes in the time intervals between consecutive R waves. It provides information on the autonomic nervous system regulation and it is a predictor of adverse cardiovascular events. Several studies analyzed this parameter in youth and adults with Intellectual Disability (ID). Nevertheless, there is a lack of information regarding the HRV before, during, and after exercise in older adults with ID. Therefore, we aimed to describe and compare the cardiac autonomic modulation before, during, and after the six-minute walk test (6MWT) in older adults with and without ID. Twenty-four volunteers with ID and 24 without ID (non-ID) participated in this study. HRV was assessed by R-R intervals at rest, during and after the 6MWT. At rest and recovery periods, the participants remained sited. The symbolic analysis was used to evaluate non-linear HRV components. The recovery HR kinetics was assessed by the mean response time, which is equivalent to time constant (τ)+time delay (TD). Between groups differences in HRV variables were not significant. During the recovery period, HR kinetics time variables showed significant better results in non-ID participants (TD: 6±5s vs. 15±11s; τ: 19±10s vs. 35±17s; and MRT: 25±9s vs. 50±11s, all p<0.050). In conclusion, our results suggest that the HRV in older adults with and without ID is similar during rest, exercise, and recovery. Recovery HR kinetics after the 6MWT was slower in older adults with ID. The reason for these results may be a reduced post-exercise vagal rebound in older adults with ID.

Tryptophan Metabolites and Aryl Hydrocarbon Receptor in Severe Acute Respiratory Syndrome, Coronavirus-2 (SARS-CoV-2) Pathophysiology

The metabolism of tryptophan is intimately associated with the differential regulation of diverse physiological processes, including in the regulation of responses to severe acute respiratory syndrome, coronavirus-2 (SARS-CoV-2) infection that underpins the COVID-19 pandemic. Two important products of tryptophan metabolism, viz kynurenine and interleukin (IL)4-inducible1 (IL41)-driven indole 3 pyruvate (I3P), activate the aryl hydrocarbon receptor (AhR), thereby altering the nature of immune responses to SARS-CoV-2 infection. AhR activation dysregulates the initial pro-inflammatory cytokines production driven by neutrophils, macrophages, and mast cells, whilst AhR activation suppresses the endogenous antiviral responses of natural killer cells and CD8+ T cells. Such immune responses become further dysregulated by the increased and prolonged pro-inflammatory cytokine suppression of pineal melatonin production coupled to increased gut dysbiosis and gut permeability. The suppression of pineal melatonin and gut microbiome-derived butyrate, coupled to an increase in circulating lipopolysaccharide (LPS) further dysregulates the immune response. The AhR mediates its effects via alterations in the regulation of mitochondrial function in immune cells. The increased risk of severe/fatal SARS-CoV-2 infection by high risk conditions, such as elderly age, obesity, and diabetes are mediated by these conditions having expression levels of melatonin, AhR, butyrate, and LPS that are closer to those driven by SARS-CoV-2 infection. This has a number of future research and treatment implications, including the utilization of melatonin and nutraceuticals that inhibit the AhR, including the polyphenols, epigallocatechin gallate (EGCG), and resveratrol.

Effects of walkability on physical activity and obesity: a prospective observational study protocol

INTRODUCTION

The prevalence of overweight and obesity is increasing worldwide, which could lead to a set of chronic and metabolic diseases. Physical activity is a modifiable factor for obesity, which was reported to be correlated with the built environment. However, the effects of the built environment on physical activity are not consistent. Walkability is a convenient way to assess the built environment. We aim to prospectively explore the relationship among walkability, physical activity and obesity in Chinese participants in Chongqing, a hilly city and provide evidence for future urban planning.

METHODS AND ANALYSIS

Participants will be recruited from people who receive health examination in the Health Management Centre, the First Affiliated Hospital to Army Medical University. Exposure variables are WalkScores calculated within the areas around workplace and residential addresses of participants. The primary outcomes are body mass index measured through health examination at baseline and follow-ups, and daily walking steps recorded by WeChat mini application for 30 days after every time of health examination. Other health-related data of the participants will also be collected. Multivariate regression analysis will be performed to examine the relationship between exposure variables and outcomes.

ETHICS AND DISSEMINATION

The Protocol is approved by the Ethics Committee of the First Affiliated Hospital to Army Medical University (KY201839). The results will be actively disseminated through peer-review journals and conference publications.

REGISTRATION NUMBER

Chinese Clinical Trial Registry (ChiCTR1800017680).