Standard Deviation Of The NN Intervals Research Articles

Effects of eating together online on autonomic nervous system functions: a randomized, open-label, controlled preliminary study among healthy volunteers

BackgroundEating alone has been significantly associated with psychological distress. However, there is no research that evaluates the effects or relation of eating together online to autonomic nervous system functions.MethodsThis is a randomized, open-label, controlled, pilot study conducted among healthy volunteers. Participants were randomized into either an eating together online group or an eating-alone group. The effect of eating together on autonomic nervous functions was evaluated and compared with that of the control (eating alone). The primary endpoint was the change in the standard deviation of the normal-to-normal interval (SDNN) scores among heart rate variabilities (HRV) before and after eating. Physiological synchrony was investigated based on changes in the SDNN scores.ResultsA total of 31 women and 25 men (mean age, 36.6 [SD = 9.9] years) were included in the study. In the comparison between the aforementioned groups, two-way analysis of variance revealed interactions between time and group on SDNN scores. SDNN scores in the eating together online group increased in the first and second halves of eating time (F[1,216], P < 0.001 and F[1,216], P = 0.022). Moreover, high correlations were observed in the changes in each pair before and during the first half of eating time as well as before and during the second half of eating time (r = 0.642, P = 0.013 and r = 0.579, P = 0.030). These were statistically significantly higher than those in the eating-alone group (P = 0.005 and P = 0.040).ConclusionsThe experience of eating together online increased HRV during eating. Variations in pairs were correlated and may have induced physiological synchrony.Trial registrationThe University Hospital Medical Information Network Clinical Trials Registry, UMIN000045161. Registered September 1, 2021. https://center6.umin.ac.jp/cgi-open-bin/icdr/ctr_view.cgi?recptno=R000051592.

Heart rate variability as a predictor of mechanical ventilation weaning outcomes

BackgroundDelays in the mechanical ventilation (MV) weaning process increase mortality. The spontaneous breathing test is the gold standard to assess weaning and extubation success, although it has approximately 85% accuracy. Studies have demonstrated a correlation between decreased heart rate variability (HRV) and weaning failure. ObjectivesTo assess the usefulness of HRV as a predictor of MV weaning outcomes. MethodsCross-sectional analytical study in adults of both sexes on MV in intensive care unit (ICU) stay. Patients were divided into weaning success and failure groups. Clinical data were collected, and HRV records were obtained with a heart rate monitor. ResultsThe study included 68 individuals – 91.1% in the weaning success group and 8.9% in the failure group. All HRV indices analyzed in both groups were lower than the reference values. No statistical difference was found in the mean RR interval (RRi), the standard deviation of the NN interval (SDNN), and the square root of the mean squared differences of successive NN intervals (RMSSD) between the groups. The weaning failure group had a significant increase in LF (41 vs. 69.4) and LF/HF ratio (0.685 vs. 2.6) and a significant decrease in HF (58.85 vs. 30.2). ConclusionsHRV measure with spectral analysis can be a good predictor of MV weaning failure. Integrating this assessment tool in ICU to predict weaning outcomes could provide more precise prognoses and more adequate assistance quality.

Autonomic dysfunction in COVID-19 patients receiving mechanical ventilation: A cross-sectional study

Coronavirus disease 2019 (COVID-19) can damage cardiac tissue by increasing troponin levels and inducing arrhythmias, myocarditis, and acute coronary syndrome. To analyze the impact of COVID-19 on cardiac autonomic control in mechanically ventilated intensive care unit (ICU) patients. This cross-sectional analytical study of ICU patients of both sexes receiving mechanical ventilation was conducted in a tertiary hospital. 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. 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. 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.

Effect of Surya Namaskar on Autonomic Status and Serum Cortisol Levels in Male Medical Students: A Longitudinal Study

Introduction: Stress is an unavoidable and ongoing phenomenon in human life that affects physiological processes in the body. Regular practice of Surya Namaskar, a yogic exercise, has been shown to improve autonomic functions by reducing sympathetic activity, thereby decreasing stress levels and improving cortisol levels. Aim: To evaluate the effects of Surya Namaskar on autonomic status and serum cortisol levels among medical students. in the Department of Physiology at the Faculty of Medicine and Health Sciences, SGT University, Gurugram, Haryana, India. The study duration was three months, from November 2021 to January 2022. A total of 30 male medical students, aged between 18 and 21 years, were included in the study. Blood samples for cortisol estimation were collected before the start of the study and after six weeks of regular yogic practice. Parameters such as mean pulse rate, Blood Pressure (BP), and Low Frequency to High Frequency (LF/HF) ratio were also studied during these two time points. Statistical analysis of Heart Rate Variability (HRV) parameters, including Standard deviation of the N-N interval (SDNN), mean Heart Rate (HR), and pNN50, was performed using Analysis of Variance (ANOVA) at baseline and after six weeks. Comparison of serum cortisol levels within the groups was done using paired t-tests. Results: The mean age of the study participants was 20.37 years. Comparison of HRV frequency domain parameters (LF, HF, and LF/HF ratio) at baseline, day one, and after six weeks of yogic practice showed statistically significant variations in LF/ HF ratio after six weeks (p-value=0.001). Baseline serum cortisol levels compared to levels after six weeks of yogic practice were also found to be statistically significant (p&lt;0.001). Conclusion: There is a positive association between cortisol levels and autonomic parameters, as evidenced by the results of the autonomic battery of tests. Incorporating yogic interventions into one’s lifestyle helps reduce sympathetic parameters and shift the balance towards parasympathetic dominance.

Effects of a one-week vacation with various activity programs on well-being, heart rate variability, and sleep quality in healthy vacationers—an open comparative study

ObjectivesThis open comparative study aimed to analyze the effects of a one-week vacation with various activity programs on well-being, heart rate variability (HRV) and sleep quality in healthy vacationers.MethodsFifty-two healthy untrained vacationers spent a one-week vacation with regular exercise in East Tyrol. Exercise was performed on six of seven days. The study participants were divided into a) Group 1, playing golf (G), and b) Group 2 performing Nordic walking or e-biking (NW&EB). Well-being was measured with the WHO-5 well-being-index; stress and recovery status was obtained with the EBF-24-questionnaire (recovery-stress questionnaire). HRV parameters in the time and frequency domain (SDNN, pNN50, r-MSSD, log LF/HF and total power) were measured with a 24-h-ECG (electrocardiogram). Sleep quality was derived from the EBF-24 questionnaire and sleep architecture from HRV-analysis. Examinations were performed one day before and after the vacation.ResultsWell-being significantly improved in the G group (+ 40%, p < 0.001) and NW&EB group (+ 19%, p = 0.019). The stress and recovery profile also improved significantly in both groups (stress-decrease: -43.7% G group; -44.7% NW&EB group; recovery-increase: + 23.6% G group; + 21.5% NW&EB group). Except for the SDNN (standard deviation of the NN interval), no significant change was noted in HRV-parameters. SDNN improved significantly only in the NW&EB group (+ 9%, p < 0.05). Sleep quality (+ 21% G group, p = 0.029; + 19% NW&EB group, p = 0.007) and architecture (-10% G group, p = 0.034; -23% NW&EB group, p = 0.012) significantly improved in both groups.ConclusionA short-term vacation with regular exercise was well tolerated by the study participants and improved well-being, sleep quality, HRV and autonomic regulation.Trial registrationRegistry and the registration no. of the study/trial: Approval was received from the ethics committee of the Leopold Franzens University of Innsbruck (AN2013-0059 332/4.8).

Abstract 15665: Pod-Based Electronic Cigarette Use Alters Measures of Heart Rate Variability

Background: Previous studies demonstrate changes in autonomic function with combustible and earlier generation electronic cigarette (ecig) use. We sought to explore the effects of nicotine salt containing pod-based ecigs on autonomic regulation in young adult regular users by analyzing indices of heart rate variability (HRV). Methods: We enrolled healthy adults (18-45 yo) who were self-reported tobacco nonusers, pod-based ecig users, or combustible cigarette users. Participants were asked to refrain from tobacco product use at least 6 h before the study visit. Indices of HRV: standard deviation of the NN intervals (SDNN) and the root mean square differences of successive NN intervals (RMSSD, measure of parasympathetic function) were measured by Sphygmacor before and 10 minutes after structured use of participants’ own product. Measurements of urinary levels of cotinine, a nicotine metabolite, and 3HPMA, an acrolein metabolite, were made 1 h after product use. Results: In 133 subjects (age 26±5, 49% women), baseline HRV measures were comparable among tobacco non-users (N=39), pod-based ecig users (N=64), and combustible cigarette users (N=30). Analyses adjusted for age and sex demonstrated that acute pod-based ecig use reduced SDNN compared with non-use (-5.9±2.6ms vs 6.5±3.2ms, P=0.004) and similar to the effect of combustible cigarette use (-10.2±3.8ms, P=0.37). Moreover, acute pod-based ecig use reduced RMSSD compared with non-use (-5.6±3.3ms vs 5.4±4.1ms, P=0.04) and similar to the effect of combustible cigarette use (-10.9±4.9ms, P=0.38). Urinary cotinine, reflective of nicotine exposure, was associated with decreases in SDNN and RMSSD (r=-0.33, P=0.001; r=-0.29,P=0.003, respectively) whereas 3HPMA associated with SDNN and showed a trend toward association with RMSSD (r=-0.27, P=0.006; r=-0.18, P=0.06, respectively). Conclusion: Our data demonstrate an association between acute use of pod-based ecigs and altered cardiac autonomic function in association with the level of nicotine and acrolein exposure.

The development and clinical application of a novel schizophrenia screening system using yoga-induced autonomic nervous system responses.

Background: In severe cases, schizophrenia can result in suicide and social isolation. Diagnosis delay can lead to worsening symptoms, and often results in prolonged therapy. An estimated 50%–80% of patients with schizophrenia are unaware of their condition. Biomarkers for schizophrenia are important for receiving a diagnosis from a psychiatrist at an early stage. Although previous studies have investigated near-infrared spectroscopy as a biomarker for schizophrenia, the required equipment is expensive and not designed for home use. Hence, we developed a novel home-use schizophrenia screening system that uses a wearable device to measure autonomic nervous system responses induced by yoga, which is frequently adopted in rehabilitation for schizophrenia. Materials and methods: The schizophrenia screening system automatically distinguishes patients with schizophrenia from healthy subjects via yoga-induced transient autonomic responses measured with a wearable wireless electrocardiograph (ECG) using linear discriminant analysis (LDA; Z score ≥ 0 → suspected schizophrenia, Z-score < 0 → healthy). The explanatory variables of LDA are averages of four indicators: components of heart rate variability (HRV): the very low-frequency (VLF), the low-frequency (LF), HR, and standard deviation of the NN intervals (SDNN). In the current study, HRV is defined as frequency domain HRV, which is determined by integrating RRI power spectrum densities from 0.0033 to 0.04 Hz (VLF) and 0.04–0.15 Hz (LF), and as time domain HRV, SDNN of which is calculated as the mean of the standard deviations of the RR intervals. These variables were measured before (5 min), during (15 min), and after (5 min) yoga in a 15-min mindfulness-based yoga program for schizophrenia (MYS). The General Health Questionnaire-28 (GHQ28) score was used to assess the severity of mental disorders for patients with schizophrenia and healthy volunteers. Twelve patients with schizophrenia (eight female and four male, 23–60 years old) and 16 healthy volunteers (seven female and nine male, 22–54 years old) were recruited. Results: The schizophrenia screening system achieved sensitivity of 91% and specificity of 81%. Z-scores of LDA were significantly correlated with GHQ28 scores (r = 0.45, p = 0.01). Conclusion: Our proposed system appears to be promising for future automated preliminary schizophrenia screening at home.

Effects of Missing Data on Heart Rate Variability Metrics.

Heart rate variability (HRV) has been studied for decades in clinical environments. Currently, the exponential growth of wearable devices in health monitoring is leading to new challenges that need to be solved. These devices have relatively poor signal quality and are affected by numerous motion artifacts, with data loss being the main stumbling block for their use in HRV analysis. In the present paper, it is shown how data loss affects HRV metrics in the time domain and frequency domain and Poincaré plots. A gap-filling method is proposed and compared to other existing approaches to alleviate these effects, both with simulated (16 subjects) and real (20 subjects) missing data. Two different data loss scenarios have been simulated: (i) scattered missing beats, related to a low signal to noise ratio; and (ii) bursts of missing beats, with the most common due to motion artifacts. In addition, a real database of photoplethysmography-derived pulse detection series provided by Apple Watch during a protocol including relax and stress stages is analyzed. The best correction method and maximum acceptable missing beats are given. Results suggest that correction without gap filling is the best option for the standard deviation of the normal-to-normal intervals (SDNN), root mean square of successive differences (RMSSD) and Poincaré plot metrics in datasets with bursts of missing beats predominance (), whereas they benefit from gap-filling approaches in the case of scattered missing beats (). Gap-filling approaches are also the best for frequency-domain metrics (). The findings of this work are useful for the design of robust HRV applications depending on missing data tolerance and the desired HRV metrics.

Effect of behavioral activation on time and frequency domain heart rate variability in older adults with subthreshold depression: a cluster randomized controlled trial in Thailand.

BackgroundIncreased prevalence of depression highlights the need for effective interventions. Behavioral activation (BA), which can easily be adapted for non-clinical populations, has been the recommended treatment for depression. It is based on a model of psychopathology explaining that losses or chronically low levels of positive reinforcement yield behavioral and emotional changes in depression and that encouraging individuals to increase their engagement in reinforcing activities can improve their mood and enhance their valuable life experiences. Heart rate variability (HRV) provides indices of autonomic function related to depression, but only a few studies have investigated the effect of BA on HRV, particularly among older adults with subthreshold depression. Accordingly, we aimed to investigate the effect of BA on HRV in older adults with subthreshold depression.MethodsWe conducted a 9-month cluster randomized controlled trial in two Health Promoting Hospitals (HPHs). Eighty-two participants were randomized into either intervention (BA with usual care) or control (usual care only) groups, with 41 participants per group. Daily step count was collected weekly during the 12-week BA intervention period, while HRV parameters, including the Standard Deviation of the Normal-to-Normal interval (SDNN), High Frequency (lnHF), Low Frequency (LF), and Low Frequency/High Frequency ratio (LF/HF), were examined at 0, 3, 6 and 9 months. Generalized Estimating Equations (GEEs) were used in the data analysis.ResultsOver nine months, the intervention and control groups differed significantly in the unadjusted mean change of HRV, SDNN [7.59 ms (95% CI: 1.67, 13.50)], lnHF [0.44 ms2 (95% CI: 0.04, 0.85)], and LF [0.53 ms2 (95% CI: 0.09, 0.98)], whereas the groups did not differ significantly in LF/HF ratio [0.01 ms2 (95% CI: -0.04, 0.06)].ConclusionOur results suggest that BA may have a therapeutic effect on depression symptoms of older adults with subthreshold depression via improved HRV.Trial registrationTCTR20211019003, thaiclinicaltrials.org, retrospectively registered on 19 October 2021. Supplementary InformationThe online version contains supplementary material available at 10.1186/s12888-022-03962-8.

Effect of Resonance Breathing on Heart Rate Variability and Cognitive Functions in Young Adults: A Randomised Controlled Study.

Introduction: Heart rate variability (HRV) is an important physiological biomarker of wellbeing, mood, and adaptation, and hence improvements in HRV signify improved health, mood, and adaptation to stress. Resonance breathing has consistently been shown to increase HRV, mood, and adaptability. The study investigated the effects of four-week training of resonance breathing in young adults on HRV, stress, and cognition functions.Methods: The randomized controlled study was conducted on young men (18-30 years) after obtaining Institutional Ethics Committee approval and written informed consent from the participants. Participants were randomly divided into two groups: the control group and the resonance breathing (RB) group. Baseline parameters, along with heart rate variability, trail tests for cognition, and perceived stress level, were assessed in both groups. After undergoing four weeks of training, the intervention group practiced deep breathing at the resonance frequency for 20 minutes per day for four weeks, whereas the control group did not. All parameters were recorded again after four weeks of resonance breathing.Results: No difference was observed in the HRV parameters in the control group at baseline and four weeks after the baseline recording (p>0.05). In the intervention group, there was a significant improvement in the HRV parameters, the standard deviation of the normal-to-normal interval (SDNN), the proportion derived by dividing NN50 by the total number of NN intervals (pNN50), and total power, after practicing four weeks of resonance breathing (p<0.05). A significant difference in these parameters was also observed in the control and intervention groups after four weeks (p<0.05). There was a significant improvement in the Trails A and B test performance in the intervention group after practicing for four weeks of RB. Similarly, the perceived stress score decreased significantly in the RB group in comparison to its baseline value as well as the control group value. Conclusion: Increased parasympathetic and decreased sympathetic activity were observed after practicing 20 minutes of resonance frequency breathing every day for four weeks. It also improved cognition and reduced perceived stress levels among young adults. It is recommended that young adults should practice deep breathing at the resonance frequency for a few minutes every day. This would allay anxiety and stress, improve their cognitive performance, and also reduce their cardiovascular morbidity.

Presentation and Evaluation of a Manual for Heart Rate Variability Biofeedback in Somatic Symptom Disorder

Background: There is initial evidence for the efficacy of heart rate variability biofeedback (HRV-BF) in depression, anxiety disorders, and functional somatic syndromes. In somatic symptom disorder (SSD), evidence is lacking. The aim of this study was to describe a newly developed HRV-BF brief intervention and to analyze HRV changes, and to examine the applicability and acceptance in SSD. Methods: We analyzed the data of the subsample of a pilot randomized controlled trial (22 subjects with SSD) who received HRV-BF over 4 sessions. We assessed HRV (SDNN: standard deviation of the NN interval, RMSSD: root mean square of successive differences between NN interval, LF: low frequency) and the subjective evaluation and acceptance of the intervention. Results: HRV analyses within therapy sessions showed that individuals learned to increase their HRV significantly during biofeedback sessions and were able to maintain it during self-regulation periods without feedback (SDNN, RMSSD, LF: 5.7 ≤ F_t ≤ 11.1). Moreover, HRV improved across sessions (SDNN). The majority of participants rated the intervention very positively (e.g., satisfaction, improvement in mood and physical well-being). Conclusions: HRV-BF can be learned within 4 sessions and shows positive effects in patients with SSD. Adding HRV-BF to existing treatments, e.g., psychotherapy, seems promising.

Effects of Long-Term Regular Continuous and Intermittent Walking on Oxidative Stress, Metabolic Profile, Heart Rate Variability, and Blood Pressure in Older Adults with Hypertension.

It is documented that regular exercise is beneficial for improving the antioxidant system, metabolic system, cardiac autonomic function, and blood pressure in those with hypertension. In this regard, low-intensity exercise is recommended for older adults, particularly those with chronic diseases. This study aimed to compare the effects of long-term regular continuous walking with intermittent walking on oxidative stress, metabolic profile, heart rate variability, and blood pressure in older adults with hypertension. Forty-three participants with hypertension aged 60–80 years were randomly divided into the continuous or intermittent walking (CON or INT) groups. Participants in the CON group walked for 30 min, 3 days/week for 12 weeks. Participants in the INT group split 30 min walking into 3 identical sessions punctuated by a 1 min rest after each session, 3 days/week for 12 weeks. Antioxidant and oxidative stress markers, metabolic markers, heart rate variability, and blood pressure were evaluated before and after the exercise program. Glutathione (GSH), GSH to GSH disulfide (GSSG) ratio, and total GSH increased significantly, and GSSG and malondialdehyde decreased significantly in both groups (p < 0.05) without significant differences between groups. Triglycerides, ratio of total cholesterol to high-density lipoprotein cholesterol, and atherosclerogenic index were significantly lower in the CON group than those in the INT group (p < 0.05). The standard deviation of the NN intervals and root mean square of the successive differences were significantly higher, and low-frequency power was significantly lower in the INT group than that in the CON group (p < 0.05). No significant changes in blood pressure were noted in both groups, and nor were there any significant differences between groups. Long-term regular continuous and intermittent walking may comparably increase antioxidants, reduce oxidative stress, and be beneficial for improving important blood pressure-related outcomes, including metabolic profile or cardiac autonomic function in older adults with hypertension.

Physiological indicators and subjective restorativeness with audio-visual interactions in urban soundscapes

The present study aimed to identify the trends of changes in physiological indicators and subjective restorativeness in response to audio-visual interactions in the environment. Four scenarios types were presented using four different modalities (video-sound, image-sound, sound-only, and video-only; each modality was evaluated by independent groups of subjects). The physiological responses and subjective restoration of subjects were measured to assess the interactions between the audio-visual modalities. These data were also analysed to determine the physiological and subjective differences between dynamic and static visual presentations. We found that with visual modalities, the heart rate (HR), heart rate variability (HRV) calculated using the standard deviation of the NN intervals (SDNNHRV), high-frequency band in the HRV power spectrum (HFHRV), alpha reactivity on electroencephalography, and skin temperature (ST) decreased; however, the beta reactivity on EEG and skin conductance level (SCL) increased. With auditory modalities, the SDNNHRV, HF-HRV, ST, and respiration depth decreased; however, the respiration rate and SCL increased. Use of static images and sound to reproduce the natural environment evoked more physiological comfort and subjective restorativeness. These findings could provide physiological insights for the theory of the restorative environment.

Autonomic Imbalance Increases the Risk for Non-alcoholic Fatty Liver Disease.

BackgroundAlthough autonomic imbalance is associated with an increased risk for metabolic disease, its effects on nonalcoholic fatty liver disease (NAFLD) remains unclear. We aimed to evaluate whether autonomic dysfunction predicts the risk for nonalcoholic fatty liver disease (NAFLD).MethodsA total of 33,899 participants without NAFLD who underwent health screening programs between 2011 and 2018 were enrolled. NAFLD was identified by ultrasonography. Autonomic activity was estimated using heart rate variability (HRV). Time domain [standard deviation of the normal-to-normal interval (SDNN) and root mean square difference (RMSSD)]; frequency domain [total power (TP), low frequency (LF), and high frequency (HF), and LF/HF ratio were analyzed.FindingsA total 6,466 participants developed NAFLD within a median of 5.7 years. Subjects with incident NAFLD showed decreased overall autonomic modulation and vagal activity with lowered SDNN, RMSSD, HF, normalized HF, compared to those without NAFLD. As the SDNN, RMSSD, TP, LF, and HF tertiles increased, the risk of NAFLD decreased with tertile 1 being the reference group [the hazard ratios (95% confidence intervals) of tertile 3 were 0.90 (0.85–0.96), 0.83 (0.78–0.88), 0.91 (0.86-0.97), 0.93 (0.87-0.99) and 0.89 (0.83-0.94), respectively] after adjusting for potential confounders. The risk for NAFLD was significantly higher in subjects in whom sustained elevated heart rate, normalized LF, and LF/HF ratio values than in those with sustained decrease in these parameters during follow-up.ConclusionsOverall autonomic imbalance, decreased parasympathetic activity, and recently increased sympathetic activity might increase the risk of NAFLD.

The effects of immersive garden experience on the health care to elderly residents with mild-to-moderate cognitive impairment living in nursing homes after the COVID-19 pandemic

Elderly patients living in long-term care facilities have been restricted from leaving to comply with social distancing guidelines during the COVID-19 pandemic. This has led to a worsening of disorders, such as anxiety and depression. This study aims to understand the health benefits of an immersive garden experience to elderly nursing home residents with mild-to-moderate cognitive impairments. Virtual reality devices were used to provide immersive garden experiences for the residents who were unable to go outside. The heart rate and heart rate variability (HRV) data of the participants of the participants were collected using biofeedback instruments, and changes in the low frequency/high frequency (LF/HF) and the standard deviation of the NN interval (SDNN) values caused by immersive garden experiences were discussed. The results show that the immersive garden experiences were beneficial to these elderly residents. Within 6 min of completing the experiment, we found that the heart rates of participants had dropped slightly, while SDNN and HF values continued to rise. SDNN values before and after the experiment demonstrated a statistically significant improvement. Furthermore, participants expressed their satisfaction with the video intervention program. The results indicated that nursing homes can provide immersive landscape experiences to help increase HRV and SDNN of their elderly residents. This will not only help these residents recall beautiful memories of their past, but will also improve their quality of life.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11355-021-00480-9.

Autonomic Imbalance in Lymphoma Survivors.

Among the types of blood cancers, non-Hodgkin lymphoma is the most common. The usual treatments for this type of cancer can cause heart failure. A descriptive observational study was conducted that included 16 non-Hodgkin lymphoma survivors and 16 healthy controls matched by age and sex. Vagal tone was evaluated in the short term with a three-channel Holter device, and the time and frequency domains were analyzed following a previously accepted methodology to evaluate cardiac autonomic balance. The results of the analysis revealed that the standard deviation of the NN interval (F = 6.25, p = 0.021) and the square root of the mean of the sum of the differences between NN intervals (F = 9.74, p = 0.004) were significantly higher in healthy subjects than in lymphoma survivors. In the heart rate variability (HRV) index, there were no significant differences between the groups (F = 0.03, p = 0.85), nor in the parameters of the frequency domains LF (F = 1.94, p = 0.17), HF (F = 0.35, p = 0.55), and the ratio LF/HF (F = 3.07, p = 0.09). HRV values were lower in non-Hodgkin lymphoma survivors in the first year after treatment, resulting in autonomic imbalance compared to healthy paired subjects.

Effect of handholding on heart rate variability in both patients with cancer and their family caregivers: a randomized crossover study

BackgroundMany family caregivers of patients with cancer feel guilty about self-care. A meaningful relationship with patients reduces such negative feelings and functions as self-care for family caregivers. Moreover, handholding improves autonomic functions in non-cancer patients. However, the effects of handholding on both patients with cancer and family caregivers remain unknown.MethodsWe evaluated the effects of handholding on heart rate variability (HRV) in patients with cancer and their family caregivers. This randomized crossover study divided patients with cancer and their family caregivers into two trial groups: Handholding trial (the family caregiver holds the patient’s hand for five minutes) and Beside trial (the family caregiver stays beside the patient without holding their hand). The study included 37 pairs of patients with cancer who received treatment in the cancer department of a university hospital in Japan and their family caregivers (n = 74). The primary end-point was the change in HRV before and during the intervention.ResultsThe median performance status of the patients was 3. An interaction was observed between trials in the standard deviation of the normal-to-normal interval (SDNN) of HRV for family caregivers (F = 7.669; p = 0.006), and a significant difference in time course was observed between the trials (before p = 0.351; during p = 0.003). No interaction was observed between trials in the SDNN for patients (F = 0.331; p = 0.566). Only a main effect in time course (F = 6.254; p = 0.014) was observed. SDNN increased significantly during the intervention in both trials (Handholding trial: p = 0.002, Beside trial: p = 0.049).ConclusionsHandholding improves autonomic functions of family caregivers and may function as self-care for family caregivers.Trial registrationUMIN000020557. Registered on January 15, 2016.

Differential Effects of Focused Attention and Open Monitoring Meditation on Autonomic Cardiac Modulation and Cortisol Secretion.

Mindfulness-based interventions (MBIs) have been used widely as a useful tool for the alleviation of various stress-related symptoms. However, the effects of MBIs on stress-related physiological activity have not yet been ascertained. MBIs primarily consist of focused-attention (FA) and open-monitoring (OM) meditation. Since differing effects of FA and OM meditation on brain activities and cognitive tasks have been mentioned, we hypothesized that FA and OM meditation have also differing effects on stress-related physiological activity. In this study, we examined the effects of FA and OM meditation on autonomic cardiac modulation and cortisol secretion. Forty-one healthy adults (aged 20–46 years) who were meditation novices experienced 30-min FA and OM meditation tasks by listening to instructions. During resting- and meditation-states, electrocardiogram transducers were attached to participants to measure the R-R interval, which were used to evaluate heart rate (HR) and perform heart rate variability (HRV) analyses. Saliva samples were obtained from participants pre- and post-meditation to measure salivary cortisol levels. Results showed that FA meditation induced a decrease in HR and an increase in the root mean square of successive differences (rMSDD). In contrast, OM meditation induced an increase in the standard deviation of the normal-to-normal interval (SDNN) to rMSSD ratio (SDNN/rMSSD) and a decrease in salivary cortisol levels. These results suggest that FA meditation elevates physiological relaxation, whereas OM meditation elevates physiological arousal and reduces stress.

Cardiac autonomic function and cognitive performance in patients with atrial fibrillation

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Swiss National Science Foundation OnBehalf Swiss-AF Investigators Background Atrial fibrillation (AF) is associated with loss of cognition and dementia. Cardiac autonomic dysfunction has been linked to cognitive decline. We aimed to investigate if reduced cardiac autonomic function (CAF) is associated with cognitive impairment in AF patients. Methods Patients with paroxysmal, persistent and permanent AF were enrolled from a multicenter cohort study if they presented in AF ("AF group") or in sinus rhythm ("SR group") on a baseline 5-minute ECG recording. Parameters quantifying CAF (heart rate variability triangular index (HRVI), mean heart rate (MHR), the root mean square of successive differences (RMSSD) and the standard deviation of the normal-to-normal intervals (SDNN)) were calculated. We used the Montreal Cognitive Assessment (MoCA) to assess global cognitive function. Results 1,685 AF patients with a mean age of 73 ± 8 years, 29% females, were included. The MoCA score was 24.5 ± 3.2 in the AF group (n = 710 patients) and 25.4 ± 3.2 in the SR group (n = 975 patients). After adjusting for multiple confounders, lower HRVI was associated with lower MoCA scores, both in the SR group (β=0.049; 95% confidence interval (CI): 0.016 to 0.081; p = 0.003) and in the AF group (β=0.068; 95% CI: 0.020 to 0.116; p = 0.006). In the AF group, higher MHR was associated with a poorer performance in the MoCA (β=-0.008; 95% CI: -0.014 to -0.002; p = 0.014 ). Other parameters of CAF were not associated with cognition. Conclusion Our data suggest that impaired CAF is associated with worse cognitive performance in patients with AF. Elderly AF patients with impaired HRVI might undergo cognitive testing in order to screen for cognitive impairment.

Mobile Heart Rate Variability Biofeedback as a Complementary Intervention After Myocardial Infarction: a Randomized Controlled Study

BackgroundTo enhance effective prevention programs after myocardial infarction (MI), the study examined the effects and feasibility of mobile biofeedback training on heart rate variability (HRV-BF).MethodsForty-six outpatients aged 41 to 79 years with a documented MI were randomized to HRV-BF versus usual care. Generalized estimating equation (GEE) analyses were performed to test improvements in measures of short- and long-time HRV, namely, the standard deviation of the normal-to-normal intervals (SDNN) and well-being after 12 weeks of HRV-BF.ResultsThere were intervention effects for short-time HRV (d > 0.4, p < 0.04), which were partly replicated in the GEE models that accounted for control variables: In the HRV-BF group, the high-frequency HRV (group × time interaction: β = 0.59, p = 0.04) compensated for significantly lower baseline levels than the group with usual care. In an optimal dose sample (on average two HRV-BF sessions a day), SDNN significantly increased after HRV-BF (p = 0.002) but not in the waitlist control group. Compensatory trends of HRV-BF were also found for high-frequency HRV and self-efficacy. No adverse effects of the intervention were found but neither were effects on long-time HRV measures.ConclusionThe results showed the feasibility of self-guided HRV-BF for almost all post-MI patients. HRV-BF as an adjunctive behavioral treatment increased HRV, which is an indicator of lower cardiovascular risk, and self-efficacy, which suggests heightened psychological resilience. These benefits warrant confirmation and tests of sustainability in larger studies.Trial RegistrationThe trial has not been registered due to its starting point in 2017 predating the publication of the applicable CONSORT extension for reporting social and psychological intervention trials in 2018.