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Abstract Objective Evaluate autonomic function and low-grade inflammation and characterize the correlation between these variables in schoolchildren with obesity living in the Brazilian northeast region. Methods 84 children with obesity and 41 with normal weight were included in this cross-sectional study. Anthropometry, body composition, blood pressure (BP), inflammatory biomarkers, and heart rate variability (HRV) indexes were analyzed in children aged 7 to 11 years. Results children with obesity had increased systolic (p= 0.0017) and diastolic (p= 0.0131) BP and heart rate (p= 0.0022). The children with obesity displayed significantly lower SDNN, RMSSD, NN50, HF (ms), HF (nu), SD1, SD2, and higher LF (ms), LF (nu), LF/HF, SD1/SD2, DFA-α1, and DFA-α2, compared to normal weight. A lower and higher capacity for producing IL-10 (p= 0.039) and IL-2 (p= 0.009), respectively, were found in children with obesity compared to children with normal weight. Although IL-2, IL-4 and IL17A did not correlate with HRV parameters, IL-6 was positively correlated with SDNN, LF (ms) and SD2, TNF-α was positively correlated with LF/HF and SD1/SD2 ratio, and IFN-γ was positively correlated with SDNN, RMMSSD, NN50, LF (ms), HF (ms), SD1, and SD2. Conclusions The findings suggest that children with obesity have impaired autonomic function and systemic low-grade inflammation compared to children within the normal weight range, the inflammatory biomarkers were correlated with HRV parameters in schoolchildren living in the northeastern region of Brazil.
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Resumen La variabilidad de la frecuencia cardiaca (VFC) se utiliza como una señal fisiológica para evaluar la reactividad psicofisiológica al estrés. El análisis en el dominio de la frecuencia de esta señal se ha usado para describir el papel del sistema nervioso autónomo en los procesos de adaptación al estrés. Sin embargo, el uso de medidas de tendencia central para reportar los resultados de distintas poblaciones desestima las diferencias individuales en la reacción frente al estrés. El objetivo de esta investigación fue caracterizar la reactividad cardiaca ante la evocación de eventos estresantes en población universitaria. Participaron 94 estudiantes de nuevo ingreso a la carrera de psicología, de dos universidades de México. Los resultados indican un decremento consistente en la banda de alta frecuencia ante la evocación de eventos estresantes, en comparación con la banda de baja frecuencia. La caracterización de la respuesta autonómica al estrés presenta dos subgrupos acoplados (co-activación y co-inhibición); y uno desacoplado. Nuestros hallazgos, ratifican la viabilidad de la banda de frecuencia alta de la VFC como un indicador estable de reactividad al estrés, y resaltan la importancia de las diferencias específicas de la actividad autonómica en la caracterización de la respuesta fisiológica al estrés.
Abstract Heart rate variability (HRV) is used as a reliable physiological signal to assess psychophysiological reactivity to stress. Frequency-domain mathematical analysis of the HRV signal provides metrics that are associated with the performance of the autonomic nervous system. However, the use of measures of central tendency to report global results in different populations underestimates individual differences in the way people react to stress and the clinical importance of this response. The objective of this research was to characterize cardiac reactivity to the evocation of stressful events in a university population. The participants were 94 new psychology students from two universities in Mexico. A psychophysiological stress assessment was performed to estimate cardiac reactivity; the evaluation consisted of the following conditions: 1) Baseline; 2) Evocation of stress; and 3) Recovery. The participants were sitting with their eyes closed and without moving during every single one of the conditions. Four subgroups were created depending on the type of cardiac reactivity to stress. The results indicate a significant consistent decrease in the high-frequency band when evoking stressful events, compared to the low-frequency band. Similar responses were observed between the low-frequency band and the high-frequency band in 60.6% of the cases, suggesting that the antagonistic autonomic balance between the two divisions of the ANS was scarce. According to the autonomic space model and the type of stress reactivity of each student, there were two subgroups characterized by co-activation and co-inhibition modes; and one subgroup characterized by uncoupled response mode. Our findings confirm the viability of the high-frequency band of HRV as a stable indicator of stress reactivity. Likewise, evidence is generated in favor of using evocative stress stimuli to assess physiological reactivity like more personal stressors. Lastly, the importance of specific differences in autonomic activity to characterize the physiological response to stress and its possible clinical utility to propose interventions and select techniques that most effectively benefit vulnerable populations are highlighted.
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Background: Chronic obstructive pulmonary disease (COPD) is one of the major causes of morbidity and mortality throughout the world. COPD and its complications also lead to a large number of deaths every year in our country. Cardiac arrhythmias and sudden cardiac death are the major complications of COPD leading to death and disability. Such cardiac complications are often a result of autonomic dysfunction. Aims and Objectives: This study aims to find out the autonomic dysfunction in moderate COPD patients by comparing their heart rate variability (HRV) parameters with age and sex matched healthy controls. Materials and Methods: After obtaining approval from the Institutional Ethics Committee, 48 patients of moderate COPD and 54 healthy subjects were assessed and compared with respect to their HRV parameters which included Mean RR, Mean HR, SDNN, NN50, pNN50, root mean square of successive differences (RMSSD), high frequency (HF), low frequency (LF), LF/HF ratio, and SD2/SD1 ratio. Results: It was found that in comparison to healthy controls, patients of moderate COPD had significant alteration in the following HRV parameters – Mean HR (P: 0.001), RMSSD (P: 0.002), SDNN (P: 0.015), NN50 (P: 0.001), pNN50 (P: 0.000), HF (NU/normalized unit) [P: 0.033], HF (%) [P: 0.002], LF (NU/normalized unit) [P: 0.033], LF (%) [P: 0.012], and LF/HF (P: 0.033). Conclusion: As there is a significant alteration of several HRV parameters in moderate COPD patients, we conclude that HRV measurement may subserve as a simple and non-invasive tool to assess autonomic dysfunction in patients of COPD at the earliest.
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Objectives: Micro and macrovasculopathy are common complications of undertreated or undiagnosed type 2 diabetes mellitus (T2DM) patients. One of the underlying factors of macrovasculopathy is arterial stiffness, which may lead to cardiovascular and cerebrovascular diseases. Understandably, diabetic micro and macrovasculopathy affect vital functions, which may affect the well-being of the individual. However, few studies have attempted to determine arterial stiffness, cardiac autonomic neuropathy (CAN) and lipid profile separately in South Asian population and examined its associations with T2DM. Moreover, there is a need to understand the mechanistic links among cardiovascular risk factors. This forms the basis of the present study. Materials and Methods: T2DM patients of 53–62 years and age- and gender-matched healthy control subjects were recruited in the cross-sectional and observational study (n = 30 each, eight women). Anthropometric measurements, physiological parameters such as resting heart rate, peripheral blood pressure (PBP), central blood pressure (CBP), augmentation index% (AIx%), brachial-ankle pulse wave velocity and lead II ECG for analysis of heart rate variability parameters were recorded after obtaining the consent of the study participants. The lipid profile and fasting blood glucose were also analysed. Results: Peripheral systolic blood pressure was significantly higher (P = 0.05) in T2DM patients. Dyslipidaemia was evident in T2DM patients. Atherogenic index of plasma (AIP) was also significantly higher in T2DM patients. Correlation analysis revealed a positive association between AIx% with PBP and CBP as well as between AIP index and central systolic blood pressure, serum triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and very low-density lipoprotein cholesterol (VLDL-C) levels. AIP index was found to be negatively associated with HF (nu). Serum TG, high-density lipoprotein cholesterol (HDL-C) levels and AIP index have emerged as significant independent predictors of T2DM vasculopathy by multiple regression analysis. Conclusion: In the present study, atherogenic dyslipidaemia was observed in T2DM patients in combination with increased serum levels of TG, VLDL-C and decreased serum levels of HDL-C. Moreover, AIP index, a predictor cardiovascular risk, was found to be significantly higher in T2DM patients. Dyslipidaemia was found to be associated with dysregulation of autonomic nervous system in those patients. A positive association between noninvasive, surrogate markers of arterial stiffness with PBP and CBP indicates that enhanced arterial stiffness may elevate systemic arterial pressure. Therefore, early screening of T2DM patients for the estimation of serum lipid profile, arterial stiffness and cardiac autonomic neuropathy may be performed to unravel diabetic vasculopathy.
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Objectives: Angina is a symptom of coronary artery disease (CAD). Modulation of cardiac autonomic tone as assessed by heart rate (HR) variability (HRV) is found reduced in patients with CAD; myocardial ischemia, myocardial infarction and some other cardiovascular diseases. Reduced HRV has been found associated with sudden cardiac death in these CAD patients. Several patients present with anginal symptoms clinically in absence of CAD or other diseases. The status of HRV is not much clear in these patients. Thus, we aimed to assess HRV in patients with angina with and without myocardial ischemia and compare it with HRV of healthy subjects of similar age groups and follow-up patients for 1 year for cardiac/health events. Materials and Methods: The study included 61 consecutive male patients clinically presenting with angina and 30 healthy subjects. Based on Thallium-201 myocardial perfusion Single-photon emission computerized tomography (SPECT) imaging, patients were divided into two groups; patients with myocardial perfusion defects (MPD), (n = 33, age 54.91 ± 7.43 years) and patients with no MPD (NMPD), NMPD (n = 28, age 53.04 ± 8.50 years). Short-term HRV was assessed in all patients and subjects in resting supine position following standard protocol. All MPD and 25 NMPD patients could be followed up for 1 year for cardiac/health events. Results: Surprisingly, the NMPD patients showed significantly reduced HRV, Standard deviation of the N-N intervals, The square root of the mean squared differences of successive N-N intervals, Percentage of the number of interval differences of successive N-N intervals greater than >50 ms divided by total number of R-R intervals, low frequency (LF) power, High Frequency (HF) power and total power as compared to both MPD patients and healthy subjects. (Total power [NMPD vs. MPD]: 610.1 [379.9–1072.8] vs. 1508.0 [748.4–2339.4] millisecond squares (ms2 ), P = 0.001), healthy subjects (Total power: 1414.6 [1104.6-2141.5] ms2 , P = 0.001). The markers of sympathetic tone; LF (normalised unit) and LF/HF ratio were higher in NMPD patients as compared to MPD patients resulting in an altered sympathovagal balance. During a 1-year follow-up, sudden death was seen in one MPD patient (3.1%) and two NMPD patients (8%). Conclusion: The NMPD patients showed significantly reduced HRV as compared to both MPD patients and Healthy subjects with an altered sympathovagal balance. Sudden death was also seen in NMPD patients as MPD patients.
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ABSTRACT BACKGROUND: Coronavirus disease 2019 (COVID-19) can damage cardiac tissue by increasing troponin levels and inducing arrhythmias, myocarditis, and acute coronary syndrome. OBJECTIVES: To analyze the impact of COVID-19 on cardiac autonomic control in mechanically ventilated intensive care unit (ICU) patients. DESIGN AND SETTING: This cross-sectional analytical study of ICU patients of both sexes receiving mechanical ventilation was conducted in a tertiary hospital. METHODS: Patients were divided into COVID-19-positive (COVID(+)) and COVID-19-negative (COVID(-)) groups. Clinical data were collected and heart rate variability (HRV) records obtained using a heart rate monitor. RESULTS: The study sample comprised 82 subjects: 36 (44%) in the COVID(-) group (58.3% female; median age, 64.5 years) and 46 (56%) in the COVID(+) group (39.1% females; median age, 57.5 years). The HRV indices were lower than the reference values. An intergroup comparison identified no statistically significant differences in the mean normal-to-normal (NN) interval, standard deviation of the NN interval, or root mean square of successive differences in NN intervals. The COVID(+) group had an increased low frequency (P = 0.05), reduced high frequency (P = 0.045), and increased low frequency/high frequency (LF/HF) ratio (P = 0.048). There was a weak positive correlation between LF/HF and length of stay in the COVID(+) group. CONCLUSION: Patients who received mechanical ventilation had lower overall HRV indices. COVID(+) patients who received mechanical ventilation had lower vagal HRV components. These findings likely indicate clinical applicability, as autonomic control impairments are associated with a greater risk of cardiac death.
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Heart rate variability is one of the methods to evaluate cardiac autonomic nervous function. It is widely used because of its non-invasive, convenient, fast and other advantages. Various heart diseases, including cardiovascular disease, arrhythmia and myocardial disease, are closely related to autonomic dysfunction, so heart rate variability has also become one of the important indicators to predict the prognosis of heart disease. This article reviews the research status of heart rate variability and its application in heart disease.
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【Objective】 To observe the regulation of autonomic nerves in blood donors during blood donation by heart rate variability analysis and explore the possible mechanism of donation related vasovagal reaction. 【Methods】 Electrocardiogram (ECG) of 90 blood donors was monitored by Fontaine Ⅰlead during the whole process of blood donation, and the 5-min heart rate variation before, during and after blood donation was analyzed. 【Results】 During the whole process of blood donation, the sympathetic HRV index (LF nu) and the sympathetic and vagal balance ability index (LF/HF) increased, whereas the vagal nerve index (pNN50, RMSSD, HFnu) and heart rate variability index (SDNN, Total power) decreased. For baseline heart rate variability of different blood donors (first-time vs. repeated, male vs. female, 18-24 years old vs. ≥25 years old, <400 mL vs. 400 mL) before blood donation, the pNN50, RMSSD and Total power of 18-24 years old blood donors were higher, but other indicators showed no significant difference. There were differences in HRV indexes of different types of blood donors during blood donation compared with before blood donation. The decrease of pNN50 and HFnu and the increase of LF/HF were larger in experienced blood donors than in first-time blood donors. The decrease of RMSSD was larger in male blood donors than in female blood donors; the change of LF/HF was larger in blood donors aged≥25 years than in blood donors aged 18-24 years; other indicators had no significant difference. 【Conclusion】 Blood donation leads to reflex readjustment of the cardiac autonomic tone: the sympathetic nerve is excited while the vagal nerve is suppressed. The cardiac autonomic nerve function of first-time blood donors, female donors and low-age (18-24 years old) donors to blood donation stress is not fully regulated. Donation related vasovagal reaction may be related to the autonomic nerve regulation function of blood donors.
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BackgroundDepression is a kind of disease with relatively high suicide risk， which seriously affects the quality of life of patients and their families， and brings a great burden to society. Antidepressants in western medicine are effective， but the improvement of depressive symptoms is relatively limited by single use， and the combination of two antidepressants may increase the risk of adverse reactions in patients. The rational use of Chinese patent medicine and western medicine may play a complementary role， and the safety of Chinese patent medicine is high. ObjectiveTo explore the early clinical efficacy of fluoxetine combined with Shugan Jieyu capsule in the treatment of depression， and to compare the differences in efficacy， safety and influence on heart rate variability between fluoxetine combined with Shugan Jieyu capsule and fluoxetine alone， so as to provide references for clinical medication of depression patients. MethodsFrom December 2015 to June 2016， 64 patients who met the diagnostic criteria of depression in the Diagnostic and Statistical Manual of Mental Disorders， fifth edition （DSM-5） who were hospitalized in the Second Affiliated Hospital of Xinxiang Medical University were selected as the research objects， and were randomly divided into the combined medication group and the fluoxetine group with 32 patients in each group. Patients in both groups were treated with fluoxetine， while patients in the combined medication group were treated with Shugan Jieyu capsule on this basis. Patients in both groups were assessed with Hamilton Depression Scale-24 item （HAMD-24）， Hamilton Anxiety Scale （HAMA） and Heart Rate Variability （HRV） before treatment， and were assessed with HAMD-24 and Treatment Emergent Symptom Scale （TESS） at the end of the 2nd， 4th and 6th week of treatment， and HRV was analyzed again at the end of the 6th week of treatment. ResultsThe study ultimately included 60 patients with depression， with 30 cases in the combination therapy group and 30 cases in the fluoxetine group. At the end of the 2nd， 4th and 6th week of treatment， the HAMD-24 score of the combined drug group was lower than that of the fluoxetine group （t=-2.677， -3.960， -4.432， P<0.05 or 0.01）. Compared with before treatment， the 24-hour mean standard deviation of normal RR intervals （SDNN）， normal low frequency （nLF） and normal high frequency （nHF） in the combined treatment group were higher at the end of the 6th week （t=-73.970， -31.878， -38.721， P<0.01）， but significant lower in LF/HF （t=3.525， P<0.01）. At the end of the 6th week of treatment， the total effective rate of the combined treatment group was higher than that of fluoxetine group， and the difference was statistically significant （86.67% vs. 70.00%， χ2=18.764， P<0.01）. At the 2nd， 4th and 6th week of treatment， there was no significant difference in the number of adverse reactions between the two groups （P>0.05）. ConclusionCompared with fluoxetine alone， Shugan Jieyu capsule combined with fluoxetine may be better in clinical efficacy and improvement of heart rate variability in patients with depression， without increasing adverse reactions.
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@#Objective To study the relationship between preoperative heart rate variability (HRV) and postoperative atrial fibrillation (POAF) after off-pump coronary artery bypass grafting (OPCAB). Methods A retrospective analysis was performed on the clinical data of 290 patients who were admitted to the Department of Cardiovascular Surgery, General Hospital of Northern Theater Command from May to September 2020 and received OPCAB. There were 217 males and 73 females aged 36-80 years. According to the incidence of POAF, the patients were divided into two groups: a non-atrial fibrillation group (208 patients) and an atrial fibrillation group (82 patients). The time domain and frequency domain factors of mean HRV 7 days before operation were calculated: standard deviation of all normal-to-normal intervals (SDNN), root mean square of successive differences, percentage difference between adjacent normal-to-normal intervals that were greater than 50 ms, low frequency power (LF), high frequency power (HF), LF/HF. Results The HRV value of patients without POAF was significantly lower than that of patients with POAF (P<0.05). The median SDNN of the two groups were 78.90 ms and 91.55 ms, respectively. Age (OR=3.630, 95%CI 2.015-6.542, P<0.001), left atrial diameter (OR=1.074, 95%CI 1.000-1.155, P=0.046), and SDNN (OR=1.017, 95%CI 1.002-1.032, P=0.024) were independently associated with the risk of POPAF after OPCAB. Conclusion SDNN may be an independent predictor of POAF after OPCAB.
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By summarizing and analyzing the research status of the influence of needling different acupoints on heart rate variability (HRV) and autonomic nervous function, it is found that Neiguan (PC 6), Zusanli (ST 36) and Shenmen (HT 7) are common acupoints for HRV analysis involving Tongli (HT 5), Hegu (LI 4), Taichong (LR 3), Zhongwan (RN 12), Danzhong (RN 17), Xinshu (BL 15), Shenshu (BL 23) and other acupoints. Different acupoints have different influences on HRV but followed by some rules, which are possibly related to the efficacy of acupoints, meridian tropism and acupoint distributions. Needling on the same acupoint also has different influences on HRV, which is possibly affected by sample size, intervention object, data processing method and other factors, so more standardized measurement process is required in further studies.
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OBJECTIVE@#To investigate the association between short-term exposure to indoor total volatile organic compounds (TVOC) and nocturnal heart rate variability (HRV) among young female adults.@*METHODS@#This panel study recruited 50 young females from one university in Beijing, China from December 2021 to April 2022. All the participants underwent two sequential visits. During each visit, real time indoor TVOC concentration was monitored using an indoor air quality detector. The real time levels of indoor temperature, relative humidity, noise, carbon dioxide and fine particulate matter were monitored using a temperature and humidity meter, a noise meter, a carbon dioxide meter and a particulate counter, respectively. HRV parameters were measured using a 12-lead Holter. Mixed-effects models were used to evaluate the association between the TVOC and HRV parameters and establish the exposure-response relationships, and two-pollutant models were applied to examine the robustness of the results.@*RESULTS@#The mean age of the 50 female subjects was (22.5±2.3) years, and the mean body mass index was (20.4±1.9) kg/m2. During this study, the median (interquartile range) of indoor TVOC concentrations was 0.069 (0.046) mg/m3, the median (interquartile range) of indoor temperature, relative humidity, carbon dioxide concentration, noise level and fine particulate matter concentration were 24.3 (2.7) ℃, 38.5% (15.0%), 0.1% (0.1%), 52.7 (5.8) dB(A) and 10.3 (21.5) μg/m3, respectively. Short-term exposure to indoor TVOC was associated with significant changes in time-domain and frequency-domain HRV parameters, and the exposure metric for most HRV parameters with the most significant changes was 1 h-moving average. Along with a 0.01 mg/m3 increment in 1 h-moving average concentration of indoor TVOC, this study observed decreases of 1.89% (95%CI: -2.28%, -1.50%) in standard deviation of all normal to normal intervals (SDNN), 1.92% (95%CI: -2.32%, -1.51%) in standard deviation of average normal to normal intervals (SDANN), 0.64% (95%CI: -1.13%, -0.14%) in percentage of adjacent NN intervals differing by more than 50 ms (pNN50), 3.52% (95%CI: -4.30%, -2.74%) in total power (TP), 5.01% (95%CI: -6.21%, -3.79%) in very low frequency (VLF) power, and 4.36% (95%CI: -5.16%, -3.55%) in low frequency (LF) power. The exposure-response curves showed that indoor TVOC was negatively correlated with SDNN, SDANN, TP, and VLF when the concentration exceeded 0.1 mg/m3. The two-pollutant models indicated that the results were generally robust after controlling indoor noise and fine particulate matter.@*CONCLUSION@#Short-term exposure to indoor TVOC was associated with significant negative changes in nocturnal HRV of young women. This study provides an important scientific basis for relevant prevention and control measures.
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Humans , Female , Adult , Young Adult , Air Pollutants/analysis , Heart Rate/physiology , Volatile Organic Compounds/analysis , Carbon Dioxide , Particulate Matter/adverse effects , Environmental PollutantsABSTRACT
ObjectiveTo investigate the clinical effect of Guanxin Shutong capsules （GXSTC） on coronary heart failure with heart blood stasis. MethodA total of 98 coronary heart failure patients with heart blood stasis who visited the expert clinics of the Affiliated Hospital of Liaoning University of Traditional Chinese Medicine from June 2020 to August 2022 were selected. They were randomized into a control group and an observation group， with 49 in each group. The two groups were given standardized treatment according to the guidelines for coronary heart failure. On this basis， the observation group was treated with Chinese patent medicine GXSTC. The cardiac structural and functional indicators， total effective rate of symptoms， exercise tolerance， heart rate variability （HRV）， quality of life and inflammatory factor levels of the two groups before and after treatment were compared. ResultBefore treatment， there was no notable difference in high-sensitivity C-reactive protein （hs-CRP）， six minute walk test （6MWT）， minnesota living with heart failure questionnaire （MLHFQ） score， left ventricular ejection fraction （LVEF）， tumor necrosis factor-α （TNF-α）， left ventricular end-diastolic diameter （LVEDD）， N-terminal pro-brain natriuretic peptide （NT-proBNP） and HRV between the two groups， and thus the data were comparable. After treatment， the observation group had higher effective rates of traditional Chinese medicine （TCM） symptoms （Z=-2.362， P<0.05） and New York heart association class （NYHA） functional classes （Z=-2.175， P<0.05） than the control group. The two groups presented decreased LVEDD， TNF-α， NT-proBNP and hs-CRP （P<0.05， P<0.01） while increased MLHFQ， 6MWT and HRV（P<0.05，P<0.01） after treatment as compared with those before treatment， and the observation group had more decrease or increase than the control group （P<0.05， P<0.01）. ConclusionGXSTC combined with standardized treatment relieves the physical symptoms of coronary heart failure patients with heart blood stasis， improves exercise tolerance and quality of life， reduces inflammatory reaction， increases HRV， and improves cardiac structure and function.
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ABSTRACT Introduction: People with type 2 diabetes mellitus present multiple complications and comorbidities, such as peripheral autonomic neuropathies and reduced peripheral force and functional capacity. Inspiratory muscle training is a widely used intervention with numerous benefits for various disorders. The present study aimed to conduct a systematic review to identify inspiratory muscle training effects on functional capacity, autonomic function, and glycemic indexes in patients with type 2 diabetes mellitus. Methods: A search was carried out by two independent reviewers. It was performed in PubMed®, Cochrane Library, Latin American and Caribbean Literature in Health Sciences (or LILACS), Physiotherapy Evidence Database (PEDro), Embase, Scopus, and Web of Science databases. There were no restrictions of language or time. Randomized clinical trials of type 2 diabetes mellitus with inspiratory muscle training intervention were selected. Studies' methodological quality was assessed using PEDro scale. Results: We found 5,319 studies, and six were selected for qualitative analysis, which was also conducted by the two reviewers. Methodological quality varied - two studies were classified as high quality, two as moderate quality, and two as low quality. Conclusion: It was found that after inspiratory muscle training protocols, there was a reduction in the sympathetic modulation and an increase in functional capacity. The results should be carefully interpreted, as there were divergences in the methodologies adopted, populations, and conclusions between the studies evaluated in this review.
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Background: Well known facts for the rise in blood pressure, blood glucose, and cardiovascular diseases are the body fat mass that has become a major public health issue that correspond to health problems. Activation of sympathetic nervous system is directly proportional to body fat mass that results in an autonomic impairment. Aims and Objectives: The aim of the study is to compare body fat mass indices and heart rate variability (HRV) (Frequency Domain) in high body mass index (BMI) postmenopausal women. Materials and Methods: This research was directed on 104 postmenopausal women of age group 45–60 years grouped them into two. Group 1 having normal BMI (18.50–24.99) and Group 2 having high BMI >25.00 based on Asian’s classification for BMI. Approval from the Institutional Ethical Committee was obtained before beginning the study. Short-term HRV was measured in each participant by a 5-min frequency domain analysis. Results: Unpaired t-test was used to analyze all parameters of the study (control and study group). The result showed a lower level of parasympathetic and a higher sympathetic activity in the study group when matched against the control group. Conclusion: Body fat mass indices and HRV are inversely proportional in high BMI postmenopausal women and they more likely to suffer from cardiometabolic disorders in early.
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Background: Cigarette smoking induced sympathetic overdrive is one of the major independent modifiable risk factors for cardiovascular mortality and morbidity. There is altered autonomic activity with increased adrenergic activity in chronic smoking which also predisposes to cardiovascular morbidity and mortality. There are several tests that can determine the Autonomic Activity. Among them, heart rate variability (HRV), especially the time domain parameters of it, is simple, easy to perform, and non-invasive test for diagnosing autonomic dysfunction in the smokers. Aims and Objectives: The aims of this study were to compare the time domain parameters of HRV in smokers and non-smokers. Materials and Methods: The present study was carried out at autonomic function laboratory and cardiovascular function laboratory, Department of Physiology, Government Medical College, Bhavnagar, among 200 subjects, out of which 100 were smokers and 100 were non-smokers, in age group of 20–50 years. Results: There was a significant increase in mean heart rate, blood pressure, and R-R interval in smokers as compared to the non-smokers. There was also a significant decrease in all time domain parameters of HRV which suggests profound sympathetic overdrive and a decrease in vagal tone due to the actions of nicotine presents in tobacco smoke. Conclusions: Cigarette smoking plays a major role in degradation and decreased function of autonomic nervous system.
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Background: Heart rate variability (HRV) is a used to assess autonomic nervous system input to the heart. Studies on the impact of HRV on underweight are limited. Aims/Objectives: To evaluate HRV in age matched young adults of different BMI category. Methodology: This cross-sectional study was done among healthy young adult volunteers between 18 and 25 years of age. Anthropometric variables were measured. ECG was recorded in lead II configuration for 5 minutes. Heart rate variability was analysed with Kubios HRV analyzer. Results: HRV indices were reduced in underweight (UW), overweight (OW) and obese group compared to normal weight (NW) BMI group. Second order polynomial regression between BMI and HF log power in both genders shows an inverted U-shaped relationship with BMI. The association between BMI, waist circumference and body fat (percentage) with HRV indices shows a significant relation to heart rate var-iability among which waist circumference (WC) shows a greater association with HRV indices than BMI. Comparison of HRV parameters among men and women of different BMI group shows female had great-er heart rate variability compared to males across BMI Conclusions: underweight individual also have increased cardiovascular risk like obese group and ab-dominal obesity is better indicator of cardiovascular risk than BMI.
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Background: Because heart rate variability (HRV) has been linked to important clinical outcomes in various cardiovascular disease states, we investigated whether preprocedural ultrashort?term HRV (UST?HRV) differs between 1?year survivors and nonsurvivors after transcatheter aortic valve replacement (TAVR). Methods: In our single?center, retrospective, nested pilot study, we analyzed data from patients with severe aortic stenosis undergoing TAVR. All patients had preprocedural UST?HRV measured before the administration of any medications or any intervention. To investigate whether preprocedural HRV is associated with 1?year survival, we performed a logistic regression analysis controlling for Kansas City Cardiomyopathy Questionnaire 12 score. Results: In our parent cohort of 100 patients, 42 patients (28 survivors and 14 nonsurvivors) were included for analysis. Root mean square of successive differences (RMSSD) and standard deviation of NN intervals (SDNN) were lower in patients who survived to 1?year post TAVR compared to nonsurvivors [10 (IQR 8–23) vs 23 (IQR 17–33), P = 0.04 and 10 (IQR 7–16) vs 17 (IQR 11–40), P = 0.03, respectively]. Logistic regression demonstrated a trend in the association of preprocedure RMSSD with 1?year mortality and a 5% higher risk of 1?year mortality with each unit increment in UST?HRV using SDNN (OR 1.05; 95%CI 1.01–1.09, P = 0.02). Conclusion: Our data suggest an inverse relationship between preprocedural UST?HRV and 1?year survival post?TAVR.This finding highlights the potential complexity of HRV regulation in chronic vs acute illness. Prospective studies are needed to validate our findings and to determine whether UST?HRV can be used for risk stratification in patients with severe aortic stenosis.
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Background: Various studies using heart rate variability (HRV) as a tool have found reduced HRV in smokers in comparison with non-smokers. However, not many studies have studied the influence of smoking on HRV in light and heavy smokers calculated by pack years. Aim and Objective: The main aim of this study was to measure and compare the influence of smoking on autonomic functions in male light and heavy cigarette smokers using HRV. Materials and Methods: The present was conducted in the Department of Physiology, Navodaya Medical College, Raichur. Permission to conduct the study was obtained from the Institutional research ethical committee. This study was conducted among male cigarette smokers with age between 20 and 50 years who were apparently healthy. The selection of subjects participating in the study was done by simple random sampling, the subjects were residents of the Raichur district. The study group subjects were divided into light and heavy smokers considering both the amount and duration of smoking calculated by pack years. HRV was recorded by using the instrument Polygraph (AD instruments, Australia, model noML870). Statistical analysis was done by independent sample t-test to compare between the groups using EPI Info Version 7.0 software. A P < 0.05 was considered as statistically significant whereas a P < 0.001 was considered as highly significant. Results: The HRV parameters indicating sympathetic function such as low frequency (LF) component, LF power expressed in normalized unit (LFnu) and LF-HF ratio were significantly increased in heavy smokers in comparison to light smokers, whereas the HRV parameters indicating parasympathetic function such as total power, high frequency (HF) component and HF power expressed in normalized unit (HFnu) were significantly decreased in heavy smokers in comparison to light smokers. Conclusion: Increased sympathetic stimulation associated with a decrease in the cardiac vagal modulation leading to imbalance in the autonomic functions was more in heavy smokers when compared to light smokers.
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Objectives: Oncology caregivers often endure a significant amount of psychosocial stress while going through the experience of caregiving for their dependents. Exposure to chronic stress disrupts the cardiac autonomic balance and increases the risk of cardiovascular events. There is a paucity of research on the association between caregiving strain and cardiac autonomic status of primary oncology caregivers. This study aimed to assess the cardiac autonomic balance and its association with the levels of perceived strain and quality of life (QOL) of primary oncology caregivers. Materials and Methods: Forty-six individuals (30 males and 16 females) who have been primary caregivers of patients under the treatment for cancer at the Regional Cancer Centre over the past 3 months–1 year were recruited in this cross-sectional study. Cardiac autonomic status was assessed by heart rate variability (HRV) technique. The level of strain perceived and QOL of the study participants were assessed using the Modified Caregiver Strain Index (MCSI) and Caregiver QOL-Cancer (CQOL-C) questionnaires, respectively. Comparison of study parameters based on MCSI scores (low strain vs. moderate-high strain) was done using the Independent Student’s t-test. Spearman rank correlation coefficient test was performed to assess the correlation between sympathovagal balance (Low frequency [LF]/high frequency [HF]) and other study parameters. Multiple linear regression analysis was performed to predict the LF/HF ratio with independent variables MCSI score and CQOL-C score. P < 0.05 was considered statistically significant. Results: Significantly high blood pressure, LF power, LF nu (LF normalised units) and LF/HF ratio were observed among caregivers with moderate-to-high caregiving strain as compared to those with low strain levels, while significantly low HF nu (HF normalised units) and CQOL-C scores were noted among the moderate-to-high caregiving strain subgroup as compared to the low caregiving strain subgroup. LF/HF ratio revealed a significant positive correlation with the level of caregiving strain (r = 0.563, P < 0.001) and a significant negative correlation with the QOL (r = ?0.489, P = 0.001) of caregivers. However, on regression analysis, the level of caregiving strain was found to be a significant predictor of autonomic dysfunction unlike the caregivers’ QOL. Conclusion: Increased caregiving strain is associated with cardiac autonomic imbalance in primary oncology caregivers.