Total Power Of Heart Rate Variability Research Articles

Low-Intensity Laser Therapy As a Method to Reduce Stress Responses after Septoplasty.

The aim of the study was to evaluate the effectiveness of the use of photobiomodulation therapy (PBMT) to minimize acute pain in the early postoperative period in patients after septoplasty. In total, 62patients underwent septoplasty under general anesthesia (40 men and 22 women, 18-44 years old) followed by nasal tamponade. Patients of the 1st group did not undergo PBMT, and patients of the 2nd group received PBMT 3, 6, and 24 h after septoplasty (infrared pulsed laser radiation, λ = 0.890 μm, P = 10 W, 2min in the projection of the wings of the nose). After 48 h, after the removal of tampons, intranasal PBMT with a nozzle in the red range, with λ = 0.63 μm, P = 8 mW, 2 min. ULF, HF, LF, and total power of heart rate variability (HRV), pain syndrome was assessed. ULF, LF, HF, total HRV power were significantly lower in group 2, compared to group 1. In the period from 6 to 24 h after septoplasty, patients of group 1 experienced higher pain than patients with PBMT (p < 0.001). The use of PBMT after septoplasty against the background of nasal tamponade helps to reduce the severity of pain syndrome and the inflammatory response to surgical stress and, consequently, leads to less pronounced changes in the autonomic nervous system in response to surgical stress.

Changes in the Time-Domain of Heart Rate Variability and Corticosterone after Surgical Trauma to the Nasal Septum in Rats.

The aim of the work was to study changes in the time range of heart rate variability (HRV) against the background of changes in the concentration of corticosterone in blood plasma in rats after surgical trauma to the nasal septum. Septoplasty was simulated in 30 mature male Wistar rats weighing 210-290 g. ECG was recorded with subsequent analysis of the time domain of HRV, as well as blood sampling to estimate changes in the concentration of corticosterone in the blood plasma was performed. As a result, SDNN significantly increased in comparison with the control on days 2 and 3 (p < 0.001) but decreased on days 4-5 (p < 0.001) and 6 (p < 0.01). rMSSD changed in waves with two irregular peaks on days 1 and 6. SDNN/rMSSD, in comparison with the 1st day of the postoperative period, increased on the 2nd day, continued to increase (p<0.05), and then began to decrease on day 4 (p < 0.01). The total HRV power of was low throughout the postoperative period (p < 0.001), except for day 3, when it was equal to the control data. The increase in the total power index fell on day 3 after the operation (p <0.01), after which its decline was observed again. The concentration of corticosterone in the blood plasma in rats was significantly higher than before (p < 0.001). On postoperative day 2 to 4, its plateau was determined. Simulation of septoplasty leads to changes in the time range of HRV, an increase in the concentration of corticosterone in the blood plasma in rats with its maximum at the time of surgery and 24 h later, and the formation of a "plateau" on postoperative days 2 to 4, which coincides with the changes in HRV.

Effects of bilateral lung transplantation on cardiac autonomic modulation and cardiorespiratory coupling: a prospective study

BackgroundAlthough cardiac autonomic modulation has been studied in several respiratory diseases, the evidence is limited on lung transplantation, particularly on its acute and chronic effects. Thus, we aimed to evaluate cardiac autonomic modulation before and after bilateral lung transplantation (BLT) through a prospective study on patients enrolled while awaiting transplant.MethodsTwenty-two patients on the waiting list for lung transplantation (11 women, age 33 [24–51] years) were enrolled in a prospective study at Ospedale Maggiore Policlinico Hospital in Milan, Italy. To evaluate cardiac autonomic modulation, ten minutes ECG and respiration were recorded at different time points before (T0) and 15 days (T1) and 6 months (T2) after bilateral lung transplantation. As to the analysis of cardiac autonomic modulation, heart rate variability (HRV) was assessed using spectral and symbolic analysis. Entropy-derived measures were used to evaluate complexity of cardiac autonomic modulation. Comparisons of autonomic indices at different time points were performed.ResultsBLT reduced HRV total power, HRV complexity and vagal modulation, while it increased sympathetic modulation in the acute phase (T1) compared to baseline (T0). The HRV alterations remained stable after 6 months (T2).ConclusionBLT reduced global variability and complexity of cardiac autonomic modulation in acute phases, and these alterations remain stable after 6 months from surgery. After BLT, a sympathetic predominance and a vagal withdrawal could be a characteristic autonomic pattern in this population.

Response of the Cardiac Autonomic Control to Exposure to Nanoparticles and Noise: A Cross-Sectional Study of Airport Ground Staff.

Airport activity causes the emission of particulate matter and noise, two environmental contaminants and potential health hazards, particularly for the personnel operating nearby taxiways. We explored the association between exposure to fine/ultrafine particles (UFPs) and noise with heart rate variability (HRV), an early indicator of cardiovascular autonomic response, among a sample of airport ground staff. Between May and June 2018, thirty-four male operators (mean age = 43 years and SD = 6.7) underwent personal monitoring of exposure to nanoparticles and noise, and HRV during their work activity. We conducted univariate and multivariate analysis to test the effect of UFP and noise exposure HRV. Total Lung Deposition Surface Area (LDSA) was significantly associated with a decrease in HRV Total Power and Triangular index (β = −0.038 p = 0.016 and β = −7.8 × 10−5, p = 0.042, respectively). Noise peak level showed an opposite effect, which was significant for Total Power (β = 153.03, p = 0.027), and for Triangular index (β = 0.362, p = 0.035). Further investigation is warranted to clarify the effect of the concurrent exposure to UFPs and noise on early changes of cardiac autonomic regulation.

Эффективность кардиобиоуправления у подростков 15–16 лет после физической нагрузки в условиях низких температур

Short-term biofeedback (BF) training provides effective restoration of the cardiovascular system (CVS) after physical exercise. Purpose: assessment of CVS reactivity in adolescents aged 15–16 years during a heart rate variability (HRV) BF session following a speed-strength exercise (thricerepeated standing long jump) in the open air (from –1 to –10 °C). Materials and methods. Healthy adolescents were examined: an experimental group (n = 15) subject to HRV BF training (3 min) using Varikard equipment (Ramena, Russia) in order to increase the total HRV power and a control group (n = 12). The following stages of recording HRV and blood pressure indicators were singled out: background (initial indicators), period immediately after physical activity, and recovery period with HRV training (experimental group) or being at rest (control group). Results. During the recovery period after a HRV BF session, subjects from the experimental group showed significantly higher total HRV power compared with the control (p = 0.04). In experimental group individuals with a heart rate of less than 90 bpm against the background of its increase during BF training, stress index did not change significantly. In subjects with tachycardia (above 90 bpm), heart rate and stress index remained elevated at all stages. Conclusion. Short-term BF training (3 min) after a speed-strength exercise in a cold environment increases the total HRV power in adolescents; the degree of reduction in sympathetic response depends on the initial heart rate level. The relative increase in heart rate during HRV BF training after physical exercise in a cold environment indicates the need for a longer BF session (over 3 min) in order to achieve a more pronounced influence of vagal effects on the heart rhythm.

Difficulty in initiating sleep is associated with poor morning cardiovascular function

Insomnia is a risk factor for hypertension and cardiovascular events, and this association is strongest for sleep-onset insomnia. This study explored morning cardiovascular function in individuals with sleep-onset insomnia by analysing heart rate variability (HRV), blood pressure variability, and baroreflex sensitivity. Sleep quality of fifteen good sleepers and 13 individuals with sleep-onset insomnia was measured by overnight polysomnography, followed by continuous recordings of the participant's blood pressure and heart rate for 10 min immediately after they had woken up the following morning. After morning awakening (averaged time: 12.33 ± 10.48 min), a significantly reduced vagal tone assessed by HRV, including lower total power of HRV, lower high frequency of HRV, and elevated slopes of systolic as well as diastolic blood pressure in the morning with a blunted baroreflex sensitivity in the insomnia group were noted, compared to the control group. No differences in sympathetic-related activity were observed. The regulation of cardiovascular activity by the parasympathetic nervous system plays an important role in sleep-onset insomnia. Weak vagal modulation and blunted baroreflex sensitivity were evident in this insomnia subtype, which indicates that difficulty in initiating sleep can independently affect morning cardiovascular function.

Cardiovascular Responses during and after Maximal Walking in Men and Women with Symptomatic Peripheral Artery Disease

Walking is recommended for patients with peripheral arterial disease (PAD). It has been shown that patients with PAD present sharper increases in blood pressure (BP) and heart rate (HR) during maximal walking when compared with healthy subjects. Additionally, women with PAD present a worse physiological profile, and it is possible that they may present higher cardiovascular load during and after a bout of maximal walking than men. Thus, the objective of this study was to compare cardiovascular and autonomic responses during and after maximal walking between men and women with PAD and intermittent claudication (IC). Forty patients with PAD and IC (20 men and 20 women) underwent, in random order, 2 sessions: control (standing on treadmill) and exercise (maximal treadmill walking test with Gardner's protocol). During the exercise, HR and BP were measured. Before and after the sessions, cardiovascular variables (BP HR, cardiac output, peripheral vascular resistance, and stroke volume) and autonomic modulation (HR and BP variabilities and baroreflex sensitivity) were assessed. In addition, an ambulatory BP monitoring was recorded after each session. Men and women presented similar maximal walking capacity. During the walking test, HR and systolic BP increased similarly in men and women. After the maximal walking, cardiovascular and autonomic responses did not differ between the genders. In addition, postintervention ambulatory BP parameters were also similar in men and women. Therefore, in men and women, maximal walking similarly reduced clinic systolic BP and stroke volume, and increased HR and total power of HR variability during the recovery period. Men and women with PAD and IC present similar cardiovascular and autonomic responses during and after maximal walking.

M46. THE STUDY OF HEART RATE VARIABILITY AND EMOTIONAL RESPONSE TO POSITIVE AND NEGATIVE AUDIOVISUAL STIMULATION IN PATIENTS WITH SCHIZOPHRENIA

BackgroundThis study was to investigate the Heart Rate Variability (HRV) and emotional response to positive and negative audiovisual stimulation in patients with chronic schizophrenia and healthy control group.MethodsAmong 253 chronic schizophrenic patients, 104 patients were informed about this research and consented. 35 healthy control consisted of peoples that did not have past and present history of mental and physical illness. Positive and negative affect and HRV were compared between chronic schizophrenia and healthy control groups, and positive and negative affect and HRV to positive and negative audiovisual stimulation were measured. Positive and negative audiovisual stimulation was defined by an art therapy professionalist and a psychiatrist as 10 positive and negative pictures. 3 positive and negative musics were shown to two groups for 4 minutes simulta¬neously. Positive and negative audiovisual stimulation were shown to two groups during 1-week intermission. HRV was measured with Ubpulse H3, an equipment for autonomic nervous system test made by Laxtha company and also analyzed by frequency domain analysis. Emotional Empathy Scale(EES) and Positive Affect and Negative Affect Schedule (PANAS) of two groups were measured at baseline and after positive and negative audiovisual stimulation. Global Assessment of Functioning Scale(GAF) and Positive and Negative Syndrome Scale(PANSS) of chronic schizophrenia group were measured by a psychiatrist.ResultsPositive affect of patients group were significantly lower than control group, negative affect of patients group were significantly higher than control group. Low Frequency (LF), High Frequency (HF), and Total Power (TP) of HRV in patients group were significantly lowered than control group at baseline. 7 subscales of emotional empathy scale were lowered in patients group compared to control group. Positive affect of patients group was significantly less increased compared to the control group after positive audiovisual stimulation, negative affect of patients group was significantly less decreased to the control group after positive audiovisual stimulation. Positive affect of patients group was increased after negative audiovisual stimulation, but positive affect of control group was significantly decreased compared to the patients group after negative audiovisual stimulation. There was no significant difference in negative affect between two groups after audiovisual stimulation. LF of patients group was significantly higher than control group after positive audiovisual stimulation, HF and TP of patients group were significantly lowered than control group after positive audiovisual stimulation. LF of patients group was significantly higher than control group after negative audiovisual stimulation, HF and PT of patients were significantly lowered than control group after negative audiovisual stimulation.DiscussionAudiovisual stimulation in integrative arts therapy program for schizophrenia might have avoid overactive sympathetic stimulation and recommend activate parasympathetic stimulation. Integrative art therapy for schizophrenia must be sufficiently relaxed, empathetic, and promote positive affect during therapeutic process.

ЗНАЧИМОСТЬ УРОВНЯ ГИПОТЕРМИИ В НЕЙРОФИЗИОЛОГИЧЕСКИХ РЕАКЦИЯХ ОРГАНИЗМА ЧЕЛОВЕКА НА ЭКСПЕРИМЕНТАЛЬНОЕ ОБЩЕЕ ОХЛАЖДЕНИЕ

Effects of hypothermia on the character of changes in central hemodynamics, heart rate variability (HRV) and EEG were studied during an experimental whole-body cooling of 30 healthy male subjects at the age of 18–20 years. The subjects were divided into 2 equal groups by the median body temperature in the total sample (34.1 °С) during cooling. The experiment consisted of 3 steps: rest at +20 °С, 10-min exposure to -20 °С in a hypothermal chamber and rewarming at +20 °С. The parameters registered at each step included EEG, blood pressure (BP), heart rate (HR) and temperature in the external auditory meatus. In the cooling chamber, body temperature lowered reliably by 1.4–3.1 °С on the average. In both groups hypothermia reduced the index of regulatory systems strain, increased total HRV power and BP, and decreased HR. During rewarming all these parameters tended to return to baseline values. Subjects with a more distinct hypothermia (33.1 °С) displayed a weakened baroreflex reaction (slight HR reduction) accompanied by a stronger vascular reaction (significant BP rise). High baroreflex stability in the subjects with low-level hypothermia (35 °С) was evidenced by a significant HR decrease in response to the BP rise. Changes in the EEG amplitude and frequency patterns during cooling declared themselves by enhancement of the subcortex regulatory activity (reliable rise in the theta-activity). Also, the alpha-activity was increased in the subjects with high-level hypothermia and decreased in 73 % of the subjects with a low-level hypothermia which points to desynchronization of the main rhythm.

Emotion, Respiration, and Heart Rate Variability: A Mathematical Model and Simulation Analyses

Although the generation mechanism of the low-frequency (LF) component of heart rate variability (HRV) is controversial, HRV is a potential candidate in designing objective measurement methodologies for emotions. These methodologies could be valuable for several biosignal applications. Here, we have conducted a simulation analysis using a novel mathematical model that integrates emotion, respiration, the nervous system, and the cardiovascular system. Our model has well reproduced experimental results, specifically concerning HRV with respiratory sinus arrhythmia and LF, the relation between HRV total power and the respiration frequency, and the homeostatic maintenance by the baroreflex. Our model indicates the following possibilities: (i) The delay in the heart rate control process of the parasympathetic activity works as a low-pass filter and the HRV total power decreases with a higher respiration frequency; (ii) the LF component of HRV and the Mayer wave are generated as transient responses of the baroreflex feedback control to perturbations induced by an emotional stimulus; and (iii) concentration on breathing to reduce the respiration frequency can reduce LF/HF and the reduction can be fed back to the emotional status.

HRV (Heart Rate Variability) as a non-invasive measurement method for performance diagnostics and training control

Abstract The aim of this study was to determine whether non-invasive heart rate variability (HRV) recordings can be used to monitor training exercises and to estimate athletic performance. Thus far, condition and performance have been evaluated with lactate test procedures and spirometry. Several tests were conducted to determine the relationship of data from lactate test samplings, spirometry and HRV recordings. Four groups of professional athletes in different disciplines such as ball sports (n=15), martial arts (n=17), endurance sports (n=8) and hobby athletes (n=6) underwent a standardized treadmill or bicycle ergometer step test while increasing load rates, e.g. 2 km/h or 20-50 Watt every 3.5 minutes, synchronized with standardized series of lactate test sampling, spirometry and ECG recording. An inclusion criterion for all athlete groups was a minimum training frequency of an hour, five days a week focusing on continuous performance improvement. Evidence shows that offline analysis of ECG data allows conclusions on actual individual athletic performance without the need for complex instrumentation and laboratory environment. The total power parameter of the HRV reaches a plateau phase in all tested subjects and this plateau phase reaches zero near the 2 mmol threshold of lactate concentration in all subjects recorded on a bicycle ergometer. Nine out of ten subjects measured on the bicycle ergometer had negatively correlating data of lactate concentration and total power of HRV (α &lt; 0.05). Lactate measurements using treadmills require resting periods for blood sampling. As the HRV increases instantly in these resting periods, the use of bicycle ergometers, where no testing breaks are needed, is recommended for further research.

Non-restorative Sleep Caused by Autonomic and Electroencephalography Parameter Dysfunction Leads to Subjective Fatigue at Wake Time in Shift Workers.

Sleep is a physiological state that plays important role in the recovery of fatigue. However, the relationship between the physiological status of sleep and subjective fatigue remains unknown. In the present study, we hypothesized that the non-recovery of fatigue at wake time due to non-restorative sleep might be ascribed to changes in specific parameters of electroencephalography (EEG) and heart rate variability (HRV) in poor sleepers. Twenty healthy female shift-working nurses participated in the study. Subjective fatigue was assessed using the visual analog scale (VAS) at bedtime and wake time. During sleep on the night between 2 consecutive day shifts, the EEG powers at the frontal pole, HRV based on electrocardiograms, and distal-proximal gradient of skin temperature were recorded and analyzed. The results indicated that the subjects with high fatigue on the VAS at wake time exhibited (1) a decrease in deep non-rapid eye movement (NREM) (stageN3) sleep duration in the first sleep cycle; (2) a decrease in REM latency; (3) a decrease in ultra-slow and delta EEG powers, particularly from 30 to 65 min after sleep onset; (4) a decrease in the total power of HRV, particularly from 0 to 30 min after sleep onset; (5) an increase in the very low frequency component of HRV; and (6) a smaller increase in the distal-proximal gradient of skin temperature, than those of the subjects with low fatigue levels. The correlational and structural equation modeling analyses of these parameters suggested that an initial decrease in the total power of HRV from 0 to 30 min after sleep onset might inhibit the recovery from fatigue during sleep (i.e., increase the VAS score at wake time) via its effects on the ultra-slow and delta powers from 30 to 65 min after sleep onset, stageN3 duration in the first sleep cycle, REM latency, and distal-proximal gradient of skin temperature. These findings suggest an important role of these physiological factors in recovery from fatigue during sleep, and that interventions to modify these physiological factors might ameliorate fatigue at wake time.

Application of autonomic nervous function evaluation to job stress screening

The present study focuses on the evaluation of autonomic nervous function, which is increasingly being used as an objective measure of fatigue state. It has recently been reported that autonomic nervous activity, which is expressed as total heart rate variability (HRV) power, is associated with, and can be used as an objective measure of, mental and physical fatigue. Total HRV power (log (LF + HF)) has been shown to decline with ageing, and thus cannot be utilized as a fatigue index in populations with a different age composition. In the present study, we devised standard scores (deviation value) for autonomic nervous activity corrected for individual age calculated from the distribution of such activity in individual age cohorts. This allowed us to accurately evaluate an individual's autonomic nervous activity, even when that individual was part of a group with members of different ages. Standard scores were quantified using autonomic nervous function data gathered from 1,969 healthy individuals (age range 20–77 years).The efficacy of this method in mental health screening was investigated by evaluating both autonomic nervous function and subjective levels of fatigue among corporate workers. Based on results from the Brief Job Stress Questionnaire recommended by the research team of the Ministry of Health, Labour and Welfare, 103 participants were divided into two groups (a high-stress group [n = 17] and a non–high-stress group [n = 86]). Visual analog scale (VAS) scores for all fatigue-related symptoms were significantly higher among the high-stress than among the non–high-stress group (p < 0.01).The mean standard score for autonomic nervous activity was 56.3 for the non–high-stress group. The score for the high-stress group was significantly lower, at 47.9 (p < 0.01), indicating that autonomic nervous function was reduced among participants who experienced high stress. According to an analysis of raw and standard scores in each domain, autonomic nervous activity did not significantly correlate with stress-causing factors (e.g., overwork) or other factors affecting stress responses (e.g., support from supervisors and colleagues), but did exhibit a significant positive correlation with physical and mental responses to stress (r = 0.334, p < 0.01). Lower raw scores for mental and physical responses to stress represent stronger subjective symptoms. Moreover, greater stress responses were found to be associated with lower standard scores for autonomic nervous activity.In terms of fatigue-related symptoms rated using the VAS, autonomic nervous activity negatively correlated with mental stress, physical stress, fatigue/malaise, depressed mood, anxiety/fear, tension, irritation/anger, cognitive decline, and muscle/joint/general pain, and positively correlated with motivation/vitality. Reduced autonomic nervous activity was observed with high stress, confirming that standard scores for autonomic nervous activity are associated with mental and physical responses to stress and subjective fatigue-related symptoms.These results indicate that the evaluation of autonomic nervous activity using standard scores (deviation value) is a useful tool for the objective measurement of fatigue state, even in groups with members of different ages, and can be applied as a useful objective health index to evaluate industrial fatigue.

Reduction in Parasympathetic Tone During Sleep in Children With Habitual Snoring.

Introduction: Changes in the autonomic nervous system due to Obstructive Sleep Apnea (OSA) during the life span have been described. Some pediatric studies have shown cardiovascular effects in children who do not fit the criteria for OSA; namely children with mild sleep disordered breathing.Objective: We investigated heart rate variability (HRV) during sleep in children with chronic snoring and flow limitation events during sleep.Methods: Ten children and adolescents with chronic snoring and an apnea hypopnea index < 1, associated to high Respiratory Index, and 10 controls matched for age, gender, and Tanner stage were monitored following one night of habituation in the sleep laboratory. HRV was studied at each sleep stage. The time and frequency domains were calculated for each 5-min period.Results: All patients were chronic heavy snorers. They presented an apnea hypopnea index = 0.8, respiratory disturbance index = 10.2/h with lowest O2 saturation 96.1 ± 2.4%. The total power of HRV was decreased in all stages (p < 0.05). There was also a decrease in NN50 and pNN50 during all sleep stages compared to healthy controls (p = 0.0003 and p = 0.03, respectively).Conclusion: A reduction in parasympathetic tone was found in the patient group. This may represent an autonomic impairment during sleep in children with mild SDB. A reduction in HRV in children with habitual snoring could be associated with possible increases in cardiovascular risk in adulthood.Significance: The study indicates that children with habitual snoring have important parasympathetic tone changes during sleep.

A cross-sectional study of impact of body composition and anthropometry on heart rate variability in different age groups of adults

Background: Obesity adversely affects the homeostasis of a person through a combination of impairments to multiple physiological mechanisms. Autonomic functions are proposed to be in the core of different aspects of health and well-being. Aims and Objectives: The objective of this study was to assess the impact of body composition and anthropometry on heart rate variability (HRV) in different age groups of adults. Materials and Methods: A total of 140 healthy adults were randomly selected for this cross-sectional observational study. They were divided into three groups based on the age distributions: Group 1: 18–30 years (n = 51); Group 2: 31–45 years (n = 47); and Group 3: 46–60 years (n = 42). Following assessments were done in all the participants in three groups: Anthropometric measurements, body composition analysis based on the principle of bioelectric impedance, and HRV. One-way analysis of variance followed by post hoc analysis was done for intergroup comparisons and Spearman’s correlation was done to find the correlation coefficients between HRV characteristics and anthropometric measurements and body composition characteristics. P < 0.05 was considered as statistically significant. Results: The body mass index (BMI), waist circumference (WC), waist/hip ratio (WHR), body fat%, visceral fat%, and very low frequency (VLF) were found to be increasing, whereas high frequency (HF) and total power were decreasing with age. BMI, WC, fat mass, subcutaneous fat (whole body)%, and visceral fat% were significantly correlated with frequency domain characteristics of HRV. The HF and total power of HRV were negatively correlated with BMI, WC, body fat%, and visceral fat%. In addition, the significant positive correlation between LF/HF ratio and WC and visceral fat% would point to the adverse effect of central adiposity and visceral fat on sympathovagal balance. Conclusion: These results reflected parasympathetic withdrawal and sympathetic predominance with increased adiposity, associated with aging.

Abstract P331: Transition From Pre-Diabetes To Diabetes Is Associated With Worsening Of Cardiac Autonomic Neuropathy: Reversal By Anti-Diabetic Drugs

Cardiac autonomic neuropathy (CAN) occurs early in the course of diabetes leading to significant cardiovascular mortality and morbidity. Manifested as impaired heart rate variability (HRV) and baroreflex sensitivity (BRS), CAN represents an independent risk predictor of cardiac mortality. CAN development is linked to hyperglycemia; however, current understanding extends cardiovascular risk to pre-diabetic patients with slight glycemic changes. Here, we assessed the incidence and manifestation of CAN in a rat model of metabolic challenge prior to and after the development of diabetes. Rats were fed a hypercaloric (HC) diet (4.035 KCal/g vs. 3 KCal/g for control rats) composed of: weight (calories) 18.06 % fat (38.68%), 15.8% protein (15.66%), and 46.13% carbohydrates (45.73%). Stable fasting hyperglycemia developed by 16 weeks of feeding. The pre-diabetic stage was associated with signs of perivascular and epicardiac adipose inflammation (4- and 40- fold increase in IL-1β and TGF-β and 2-fold increase in NK-κB expression; and macrophage infiltration) and increased brainstem oxidative stress accompanied with impairment of HRV (total power decrease from 3098 ± 233 to 89 ± 88μs 2 ) and the parasympathetic arm of the baroreflex (slope decrease from -1.02 ± 0.12 to -0.34 ± 0.04). These abnormalities were reversed upon treatment with non-hypoglycemic doses of either metformin or pioglitazone or upon lowering the rat caloric intake. On the other hand, after progression to diabetes, the autonomic deficit progressed to the sympathetic arm of the baroreflex (Slope reduction from -0.35 ± 0.02 to -0.09 ± 0.03). The same hypoglycemic doses of metformin and pioglitazone failed to reverse the impaired HRV and BRS. Whereas, reduction of hyperglycemia to control levels by insulin was only capable of reversing the sympathetic impairment (BRS slope of -0.28 ± 0.04). Our present results outline a framework for sequential involvement of different detrimental mechanisms in the course of metabolic disease leading to differential impact on cardiac autonomic control. Furthermore, our findings emphasize the value of early intervention with antidiabetic drugs with potential protective pleiotropic effects.

Pulse pressure amplification and cardiac autonomic dysfunction in patients with type 2 diabetes mellitus.

The main aim of this cross-sectional study was to investigate the association between pulse pressure amplification (PPA) and cardiac autonomic activity (baroreflex sensitivity (BRS) and heart rate variability (HRV)) in patients with type 2 diabetes mellitus (T2DM). In addition, we examined the association between cardiac autonomic activity and central hemodynamic parameters that may affect PPA such as augmentation index (AIx), aortic stiffness (pulse wave velocity (PWV)), and common carotid artery stiffness distensibility coefficient (DC). A total of 142 patients with T2DM were included in the study. In multivariate linear regression analysis-after controlling for age, diabetes duration, height, waist circumference, aortic PWV, use of β-blockers, and BRS-PPA was associated significantly and independently with male gender (standardized regression coefficient (β) = 0.156, p = 0.007), aortic systolic blood pressure (β = -0.221, p < 0.001), heart rate (β = 0.521, p < 0.001), AΙx (β = -0.443, p < 0.001), and parameters of HRV, such as total power of HRV (β = -0.157, p = 0.005). No significant associations were found between BRS or parameters of HRV with aortic PWV, AIx, or DC. In patients with T2DM, cardiac autonomic dysfunction was associated with enhanced PPA. This association was independent from the well-described effect of resting heart rate, as well as from traditional cardiovascular risk factors or diabetes-related factors. Moreover, it was not mediated by effects of the autonomic dysfunction on arterial stiffness or on pressure wave reflections. These findings suggest that cardiac autonomic dysfunction affects PPA by mechanisms other than resting tachycardia and arterial properties.

F223. COMPARATIVE STUDY OF HEART RATE VARIABILITY AND EMOTIONAL RESPONSE TO POSITIVE AND NEGATIVE AUDIOVISUAL STIMULATION IN PATIENTS WITH CHRONIC SCHIZOPHRENIA AND HEALTHY CONTROL

BackgroundThis study was to investigate the Heart Rate Variability(HRV) and emotional response to positive and negative audiovisual stimulation in patients with chronic schizophrenia and healthy control groupMethodsAmong 253 chronic schizophrenic patients admitted in 00 Hospital in 00 city by psychiatrist, 104 patients were informed about this research and consented. Those who met this study criteria were randomly selected. 35 healthy control consisted of peoples that did not have past and present history of mental and physical illness. Positive and negative affect and HRV were compared between chronic schizophrenia and healthy control groups, and positive and negative affect and HRV to positive and negative audiovisual stimulation were measured according to planed research process. Positive and negative audiovisual stimulation was defined by an art therapy professionalist and a psychiatrist as 10 positive and negative pictures. 3 positive and negative musics were shown to two groups for 4 minutes simultaneously. Positive and negative audiovisual stimulation were shown to two groups during 1-week intermission. HRV was measured with Ubpulse H3, an equipment for autonomic nervous system test made by Laxtha company and also analyzed by frequency domain analysis. Emotional Empathy Scale(EES) and Positive Affect and Negative Affect Schedule (PANAS) of two groups were measured at baseline and after positive and negative audiovisual stimulation. Global Assessment of Functioning Scale(GAF) and Positive and Negative Syndrome Scale(PANSS) of chronic schizophrenia group were measured by a psychiatrist.Results1) Positive affect of patients group were significantly lower than control group, negative affect of patients group were significantly higher than control group. Low Frequency(LF), High Frequency(HF), and Total Power(TP) of HRV in patients group were significantly lowered than control group at baseline.2) 7 subscales of emotional empathy scale were lowered in patients group compared to control group.3) Positive affect of patients group was significantly less increased compared to the control group after positive audiovisual stimulation, negative affect of patients group was significantly less decreased to the control group after positive audiovisual stimulation.4) Positive affect of patients group was increased after negative audiovisual stimulation, but positive affect of control group was significantly decreased compared to the patients group after negative audiovisual stimulation. There was no significant difference in negative affect between two groups after audiovisual stimulation.5) LF of patients group was significantly higher than control group after positive audiovisual stimulation, HF and TP of patients group were significantly lowered than control group after positive audiovisual stimulation.6) LF of patients group was significantly higher than control group after negative audiovisual stimulation, HF and PT of patients were significantly lowered than control group after negative audiovisaul stimulation.DiscussionPatients with schizophrenia showed lower positive affect, higher negative affect, and lowered HRV parameters compared to the control group. They also showed lower empathy ability and inappropriate and non-contexual response. Schizophrenic patients represented hypersensitive sympathetic nervous system activity and lowered parasympathetic nervous system activity to the audiovisual stimulation. These results suggested that schizophrenic patients would show higher negative affect, less adaptive autonomic nervous system and hypersensitive or sharp to audiovisual stimulation, and decreased relaxation ability after stimulation. Audiovisual stimulation in integrative arts therapy program for schizophrenia might have avoid overactive sympathetic stimulation and recommend activate parasympathetic stimulation. Integrative art therapy for schizophrenia must be sufficiently relaxed, empathetic, and promote positive affect during therapeutic process.

Leptin and its Relation to Autonomic Activity, Endothelial Cell Activation and Blood Pressure in a Young Black and White Population: The African-PREDICT study

An increasing prevalence of obesity-related hypertension is observed in the youth and may have severe consequences for future cardiovascular disease development. Previous studies portrayed leptin as a potential factor involved in obesity-related hypertension development. In order to understand leptin's contributions to early cardiovascular deterioration, we investigated leptin and its associations with measures of autonomic activity, endothelial activation, and blood pressure in young healthy black and white men and women. We included 820 participants (aged 20-30 years) and determined serum leptin and endothelial cellular adhesion molecules. We measured 24-h blood pressure, heart rate, and heart rate variability components. In multivariate-adjusted regression analyses, we found consistent associations between markers of autonomic activity (such as 24-h heart rate, day and night-time heart rate as well as heart rate variability total power) and leptin in both white (all p≤0.001) and black men (all p≤0.040). These findings were absent or less prominent in women, despite their almost 10-fold higher leptin levels than men. Only in white men, 24-h diastolic blood pressure was associated with leptin (Std β=0.37; p=0.006). This association was found to be partly mediated by autonomic activity (24-h heart rate variability total power). No independent associations were observed between leptin and markers of endothelial cell activation, irrespective of race or gender. Leptin's independent association with autonomic neural activity in a young apparently healthy population suggests an early influence of leptin on autonomic function and future blood pressure elevation especially in men.

Which psychological, psychophysiological, and anthropometric factors are connected with life events, depression, and quality of life in patients with cardiovascular disease.

ObjectiveThe aim of the study was to determine psychological, psychophysiological, and anthropometric factors connected with life events, level of depression, and quality of life in people at risk for cardiovascular disease and healthy controls.MethodsThis is a cross-sectional study involving arterial hypertension patients and healthy controls. There were several measurements including physical, anthropological, cardiovascular, and psychophysiological measurements and administration of questionnaires.ResultsA total of 99 participants were recruited for this study, 54 healthy controls (mean age: 35.59±13.39 years) and 45 patients with cardiovascular disease (CVD) (mean age: 46.33±12.39 years). The healthy controls and the patients with CVD significantly differed in the mean total score of life events, level of depression, quality of life score, temperature, blood pressure (BP), pulse transit time, heart rate, high-frequency total power, heart rate variability total power, waist-to-height ratio (WHtR), body fat percentage, fat control, pulse wave velocity, and augmentation index. In healthy subjects, the total score of the life events was not correlated with any cardiovascular or anthropometric factor. A score of depression significantly correlated with the WHtR, augmentation index, body fat percentage, and fat control. The quality of life – visual scale correlated with the body temperature, BP, and percentage of body fat. In the group of the patients with CVD, the score of the life events did not correlate with any measured cardiovascular or anthropometric factor. The level of depression correlated with the augmentation index. The quality of life – visual scale significantly correlated with body temperature, WHtR, and fat control.ConclusionThe patients with CVD reported higher scores of life events, worse quality of life, and a greater level of depressive symptoms than healthy controls. In healthy controls, a higher mean total score of life events significantly negatively correlated with high-frequency total power, and the degree of depression correlated with being overweight. In patients with CVD, a score of depression was linked to being overweight.