Heart rate variability in generalized anxiety disorder, major depressive disorder and panic disorder: A network meta-analysis and systematic review

Effects of A Brief Resonance Frequency Breathing Exercise on Heart Rate Variability and Inhibitory Control in the Context of Generalised Anxiety Disorder

Generalised anxiety disorder (GAD) is associated with cognitive and physiological symptoms including uncontrollable worry, inhibitory control deficits, and low heart rate variability (HRV). Literature linking HRV and inhibition in GAD is predominantly correlational. The present experiment investigated whether HRV has a causal role in maintaining inhibitory control. Participants (N = 135, 111 female) aged 18-37 reporting high levels of symptoms associated with GAD (GAD-7 scores ≥ 10; Penn State Worry Questionnaire scores ≥ 56) were assigned to an experimental or active control condition and completed baseline measures of HRV, respiration rate, and inhibitory control. The experimental condition completed resonance frequency breathing (RFB) training, and the control condition practiced breathing at their mean breathing rate before repeating the inhibitory control assessment. Participants also completed the breathing training before a behavioural worry task. The experimental condition was predicted to show increased HRV, alongside improved inhibitory control and better ability to stop worrying as compared to the control condition. HRV increased during the experimental condition, as compared to the control condition. However, there were no significant effects of RFB on inhibitory control or worry, or on HRV during the inhibitory control tasks. In conclusion, RFB can increase HRV in high GAD scorers, but further research is required to determine whether there is a relationship between increased HRV and symptoms of GAD in a single session experiment.

Under the surface: Low cardiac vagal tone and poor interoception in young adults with subclinical depressive symptoms

INTRODUCTION

Depressive symptoms are associated with alterations in central and autonomic nervous system activity, including misperception of bodily activity (e.g., low interoception), somatic symptoms and decreased vagally mediated heart rate variability (vmHRV). However, there is a lack of studies that examine both perception of bodily activity and autonomic function in depression. The present study investigated the association between interoception, vmHRV, and subclinical depressive symptoms.

METHOD

Eighty-eight students were enrolled and vmHRV was calculated from a 5-minute resting electrocardiogram. Interoceptive accuracy (heartbeat tracking task; heartbeat discrimination task), interoceptive sensibility (Body Perception Questionnaire), and depressive symptoms (Depression, Anxiety and Stress Scale - 21 Items) were assessed.

RESULTS

Interoceptive accuracy and sensibility positively correlated with vmHRV and negatively correlates with depressive symptoms. Cluster analysis performed on vmHRV, interoceptive accuracy, and sensibility provided two clusters: the first characterized by a pattern of low interoceptive accuracy, sensibility, and decreased resting vmHRV, the second characterized by an opposite pattern. Regression analyses showed that the first cluster was characterized by significantly higher depressive symptoms compared to the second (β = 1.97; pBonferroni = 0.04), even after controlling for sex, BMI, anxiety, and stress levels.

CONCLUSIONS

Subclinical depressive symptoms are associated with a consistent impairment in the perception and interpretation of bodily activity and altered regulatory function of the autonomic nervous system. The present results suggest that the alteration of brain-body communication could be involved in subclinical depressive symptoms. Early identification of such alterations could help with targeted preventive strategies.

Preliminary study on the effect of first- and second-hand smoke of heat-not-burn tobacco products on urinary nicotine and cotinine levels and cardiovascular system

Heart rate variability (HRV) of 10 participants was assessed to evaluate the impact of exposure to first- and second-hand smoke from heat-not-burn (HnB) products and conventional cigarettes on cardiovascular health and the autonomic nervous system. The nicotine and cotinine concentrations in the urine of smokers and non-smokers exposed to this smoke were also measured. Nicotine levels in the urine of smokers exposed to HnB products and conventional cigarettes averaged 71.76 and 229.36 ng/ml, respectively. Short-term analyses of HRV in both time- and frequency-domain were performed. There were no significant differences in HRV indicators between both groups at baseline. However, decreases in SDNN, rMSSD, TINN, and pNN50 (%) were observed in smokers exposed to both first- and second-hand smoke from HnB products and conventional cigarettes. No significant trends were noted in non-smokers. The frequency-domain analysis revealed a decrease in low frequency components among smokers.

Heart rate variability in mental disorders: an umbrella review of meta-analyses

Heart rate variability (HRV) monitoring is increasingly applied in the realm of mental disorders; however, it remains a subject of controversy. This umbrella review summarizes HRV differences between individuals with mental disorders and healthy controls (HCs), as well as changes in HRV before and after treatment in patients with mental disorders. A literature search was conducted using Medline, PubMed, Embase, and the Cochrane Database. Meta-analyses on HRV changes in patients with mental disorders, as well as meta-analyses comparing HCs and patients with mental disorders were included. We computed the summary effect size using random effects models, along with 95% confidence and prediction intervals. We assessed heterogeneity, p value of the largest study, excess significance bias, and small-study effects. Evidence levels were classified as convincing, highly suggestive, suggestive, weak, or not significant. Twenty-one systematic reviews on HRV, covering 19 mental disorders (53 meta-analyses) and 8 treatment modalities (18 meta-analyses), included 442 primary studies and 34,625. For differences between mental disorders and HCs, evidence was suggestive for 7 (13.2%) pooled analyses, indicating decreased HRV in dementia, PTSD, somatic symptom disorders, functional somatic syndromes, and schizophrenia. For other disorders, including autism spectrum disorder, alcohol use disorder, bipolar disorder, generalized anxiety disorder, insomnia, and major depressive disorder, the evidence was weaker and below the suggestive level. For treatment effects, 5 pooled analyses (27.8%) had weak evidence, indicating altered HRV before and after antipsychotic treatment, repetitive transcranial magnetic stimulation treatment, physiotherapy, and psychotherapy. The credibility of HRV evidence in mental disorders varied across HRV variables and diseases. No two diseases exhibited identical altered HRV patterns, highlighting the potential significance of overall HRV profiles in delineating distinct disorders.

Heart rate variability in subthreshold depression and major depressive disorder

BACKGROUND

The relationship between heart rate variability (HRV) and major depressive disorder (MDD) has been well explored. However, current researches lack an observation of HRV in subthreshold depression (SubD), which increases the risk of MDD and presents significant societal challenges.

METHODS

This study compared resting state HRV among 128 MDD patients, 131 SubD individuals and 222 healthy controls (HC) recruited from the hospital, physical examination center, and colleges. Depression, anxiety and sleep quality were assessed by the Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7) and Pittsburgh Sleep Quality Index (PSQI) scale. Statistical analyses including Kruskal-Wallis test, spearman correlation and binary logistic regression were conducted to investigate relationships between HRV and emotional issues.

RESULTS

The results revealed increasing trends in HRV across three groups, and the top three indices correlated with self-reported symptoms were standard deviation of the Poincaré plot perpendicular along the line of identity (SD2), standard deviation of all RR intervals (SDNN) and low frequency (LF). After adjusting for demographics, lower HRV was significantly associated with increased MDD risk compared to HC or SubD. Additionally, LF, SDNN and SD2 exhibited significant associations between SubD and HC.

CONCLUSIONS

This study is the first attempt to explore the HRV in SubD and compares it with MDD/HC. Our findings indicate that HRV changes are evident in minor depression, with indices in SubD lower than HC yet higher than MDD. SDNN, LF, and SD2 emerge as potential biomarkers for identifying depression early.

Self-compassion modulates autonomic and psychological responses to stress among adults with generalized anxiety disorders

Background

Self-compassion is associated with emotional well-being, yet its benefits in generalized anxiety disorder (GAD) patients remain unclear. This study investigated the impact of self-compassion on emotional and physiological stress responses in individuals diagnosed with GAD.

Methods

Seventy-seven GAD patients were categorized into high (n = 39) and low (n = 38) self-compassion groups using the Self-Compassion Scale. Electrocardiograms were recorded during a stress-inducing task, in which negative feedback was provided on personal intelligence and career development. Participants reported state anxiety and perceived stress pre- and post-task.

Results

When exposed to a stressor, individuals with higher self-compassion had lower heart rates (t (75) = -2.06, p = 0.043), higher heart rate variability (t (75) = 2.73, p = 0.04), and lower anxiety (t (75) = -2.07, p = 0.041) compared to the lower self-compassion group. Moreover, heart rate variability was negatively correlated with anxiety across patients (r = -0.31, df = 75, p = 0.03).

Conclusion

These results highlight the role of self-compassion in managing psychological and physiological responses to stress in GAD patients and indicate the potential of self-compassion interventions in GAD treatments.

Automated classification of stress and relaxation responses in major depressive disorder, panic disorder, and healthy participants via heart rate variability

Background

Stress is a significant risk factor for psychiatric disorders such as major depressive disorder (MDD) and panic disorder (PD). This highlights the need for advanced stress-monitoring technologies to improve treatment. Stress affects the autonomic nervous system, which can be evaluated via heart rate variability (HRV). While machine learning has enabled automated stress detection via HRV in healthy individuals, its application in psychiatric patients remains underexplored. This study evaluated the feasibility of using machine-learning algorithms to detect stress automatically in MDD and PD patients, as well as healthy controls (HCs), based on HRV features.

Methods

The study included 147 participants (MDD: 41, PD: 47, HC: 59) who visited the laboratory up to five times over 12 weeks. HRV data were collected during stress and relaxation tasks, with 20 HRV features extracted. Random forest and multilayer perceptron classifiers were applied to distinguish between the stress and relaxation tasks. Feature importance was analyzed using SHapley Additive exPlanations, and differences in HRV between the tasks (ΔHRV) were compared across groups. The impact of personalized longitudinal scaling on classification accuracy was also assessed.

Results

Random forest classification accuracies were 0.67 for MDD, 0.69 for PD, and 0.73 for HCs, indicating higher accuracy in the HC group. Longitudinal scaling improved accuracies to 0.94 for MDD, 0.90 for PD, and 0.96 for HCs, suggesting its potential in monitoring patients' conditions using HRV. The HC group demonstrated greater ΔHRV fluctuation in a larger number of and more significant features than the patient groups, potentially contributing to higher accuracy. Multilayer perceptron models provided consistent results with random forest, confirming the robustness of the findings.

Conclusion

This study demonstrated that differentiating between stress and relaxation was more challenging in the PD and MDD groups than in the HC group, underscoring the potential of HRV metrics as stress biomarkers. Psychiatric patients exhibited altered autonomic responses, which may influence their stress reactivity. This indicates the need for a tailored approach to stress monitoring in these patient groups. Additionally, we emphasized the significance of longitudinal scaling in enhancing classification accuracy, which can be utilized to develop personalized monitoring technologies for psychiatric patients.

Smart furniture using radar technology for cardiac health monitoring

The integration of radar technology into smart furniture represents a practical approach to health monitoring, circumventing the concerns regarding user convenience and privacy often encountered by conventional smart home systems. Radar technology's inherent non-contact methodology, privacy-preserving features, adaptability to diverse environmental conditions, and high precision characteristics collectively establish it a compelling alternative for comprehensive health monitoring within domestic environments. In this paper, we introduce a millimeter (mm)-wave radar system positioned strategically behind a seat, featuring an algorithm capable of identifying unique cardiac waveform patterns for healthy subjects. These patterns are characterized by two peaks followed by a valley in each cycle, which can be correlated to Electrocardiogram (ECG), enabling effective cardiac waveform monitoring. The provided algorithm excels in discerning variations in heart patterns, particularly in individuals with prolonged corrected QT intervals, by minimizing high frequency breathing interference and ensuring accurate pattern recognition. Additionally, this paper addresses the influence of body movements in seated individuals, conducting a comprehensive study on heart rate variability and estimation. Experiment results demonstrate a maximum interbeat intervals (IBI) error of 30 milliseconds and an average relative error of 4.8% in heart rate estimation, showcasing the efficacy of the proposed method utilizing variational mode decomposition and a multi-bin approach.

Seasonal variations in the mental state and heart rate variability in adolescents residing beyond the Arctic Circle

Background — Residence beyond the Arctic Circle is associated with a distinct condition, Polar Tension Syndrome (PTS), which shares similarities with Seasonal Affective Disorder (SAD). However, the interplay of mental state and heart rate variability within the context of seasonal photoperiodicity in both PTS and SAD remains poorly understood. Objectives — This study investigated the effects of polar photoperiodicity on the mental and physiological states of male adolescents living in the Kola Peninsula, Russia (67°34′ N, 33°23′ E), a region beyond the Arctic Circle. Methods — Mental state was assessed using the State-Trait Anxiety Inventory (STAI) and the Self-Esteem of health, Activity, and Mood (SAM) scales. Heart rate variability (HRV) indices provided objective measures of the psychophysiological state. Results — Significant associations were found between state and trait anxiety (StA and TrA) and seasonal photoperiodicity in adolescents residing beyond the Arctic Circle. Reduced parasympathetic (HF) and increased sympathetic (LF) Autonomic Nervous System (ANS) contributions to heart rate (HR) regulation during the polar night may underlie the physiological manifestations of polar tension syndrome (PTS) and seasonal sffective disorder (SAD), both characterized by elevated anxiety. Analysis revealed monthly fluctuations in the dominance of HF and LF contributions to HR regulation, with LF predominating during the polar night and in March. Conclusion — This study demonstrates an association between state and trait anxiety (StA and TrA), heart rate regulation, and seasonal photoperiodicity in adolescents residing beyond the Arctic Circle. Adolescents with anxiety and low parasympathetic (HF) HRV activity show an increased risk of developing PTS and SAD symptoms.

Heart rate variability and perinatal depressive symptoms: A scoping review protocol

Objective

An emerging marker of depression in the perinatal period is represented by a reduction in the autonomic nervous system (ANS) activity, reflected by heart rate variability (HRV). This scoping review aims to map the association between HRV and depression during the perinatal period and to understand its potential clinical implications.

Introduction

Previous evidence associated ANS dysfunction and depressive symptomatology in the general population. Few observational and intervention studies investigated how HRV could be related to both pre- and post-partum depressive symptoms. However, high heterogeneity in the study designs and methods has been reported. Therefore, this scoping review plans to combine all these findings to build a starting point for future research.

Inclusion criteria

This scoping review will consider articles focusing on the association between HRV and depression in the peripartum and - when available - on the impact of interventions on HRV and how this correlates with changes in depressive symptoms. Studies will be included with no restrictions on participants' age, peripartum time points for the assessment, and HRV parameters collected.

Methods

We will perform a systematic search using the Medline (PubMed), PsychInfo, and Web of Science (WoS) databases. Two authors will independently screen titles, abstracts, and then full-text articles that meet the inclusion criteria. The review will include only journal articles published in English, with no time limitations. Data will be extracted and presented in tables and/or graphical representations to summarise and describe the results. Extracted data will be reported in a comprehensive summary.

Bidirectionality of LF when the movie makes you sad: Effects of negative emotions on heart rate variability among patients with major depression

OBJECTIVES

Heart rate variability (HRV) reflects the capacity to adapt to internal and environmental changes. Decreased HRV may indicate inadequate adaptive capacity. This study aims to investigate the relationship between the heart and brain's adaptive abilities, both at rest and when negative emotions are stimulated in depression.

SUBJECTS AND METHODS

The study included 30 patients (20 female, 10 male) with major depression (mean age = 29.8 ± 7.8) and 30 healthy controls, all of whom had similar characteristics in terms of age and gender, selected through convenience sampling. The patients were drug-free at the time of the assessment. Holter recordings were obtained while subjects watched videos stimulating anger, fear, sadness, and a neutral video, and at rest, HRV parameters were calculated. To control for interindividual variability and account for paired sampling, linear mixed effects models were employed.

RESULTS

Watching the 'sadness video' led to an increase in low frequency band (LF) [LF change (Control vs depression); Difference:-620.80 df:107 t:-2.093 P:0.039] and LF/high frequency band ratio (LF/HF) [LF/HF change (control vs depression group); Difference:-1.718 df:105 t:-2.374 P:0.020] in the depression group. The video led to a decrease in LF and LF/HF in the controls. Although the differences between the conditions and interactions with the group were significant, the effects were independent of depression severity.

CONCLUSION

In depression, brain's regulatory effect on the heart differed from controls in the sadness condition, possibly due to increased arousal levels in subjects with depression and their inability to suppress sympathetic activity when a state of sadness is stimulated.

Heart rate variability (HRV) after traumatic brain injury (TBI): a scoping review

BACKGROUND

Heart rate variability (HRV), defined as the variability between successive heart beats, is a noninvasive measure of autonomic nervous system (ANS) function, which may be altered following traumatic brain injury (TBI). This scoping review summarizes the existing literature regarding changes in HRV after TBI as well as the association between measures of HRV and outcomes following TBI.

METHODS

A literature search for articles assessing 'heart rate variability' and 'brain injury' or 'concussion' was completed. Articles were included if HRV was measured in human subjects with TBI or concussion. Review articles, protocol papers, and studies including non-traumatic injuries were excluded.

RESULTS

Sixty-three articles were included in this review. Varied methods were used to measure HRV in the different studies. Forty articles included information about differences in HRV measures after TBI and/or longitudinal changes after TBI. Fifteen studies assessed HRV and symptoms following TBI, and 15 studies assessed HRV and either functional or cognitive outcomes after TBI.

CONCLUSIONS

HRV has been studied in the context of mortality, clinical symptoms, and medical, functional, or cognitive outcomes following TBI. Methods used to measure HRV have varied amongst the different studies, which may impact findings, standardized protocols are needed for future research.

Compassionate mind training for people with Parkinson's disease: A pilot study and predictors of response

INTRODUCTION

People with Parkinson's disease (PD) often present with disabling neuropsychiatric symptoms. Compassionate mind training (CMT) is a psychological approach effective in reducing stress and promoting psychological well-being. Heart rate variability (HRV), a measure reflecting sympathovagal balance, has been associated with psychological well-being and a compassionate attitude.

AIM

To assess the feasibility and effectiveness of CMT in enhancing the quality of life and psychological well-being in PD patients. Additionally, we evaluated HRV as a physiomarker for assessing the CMT outcomes.

METHODS

Twenty-four PD patients participated in the study. A 6-week online CMT intervention was delivered on a weekly basis. At baseline and post-intervention patients completed questionnaires assessing depression, anxiety and quality of life. In a subsample of 11 patients, HRV was measured at baseline and post-intervention in three conditions: at rest, during stress and after 3 min of deep breathing.

RESULTS

The attendance rate was 94.3%. Quality of life and perceived stigma improved post-intervention as compared with baseline (p = 0.02 and p = 0.03 for PD Questionnaire-39 total score and Stigma subscore, respectively). After CMT, patients presented better physiological regulation to stress, as measured by higher HRV as compared with baseline (p = 0.005). Notably, patients who were more resilient to stress at baseline (less decrease in HRV during stress) experienced a more substantial reduction in anxiety and depression following CMT.

CONCLUSIONS

CMT is feasible and can improve quality of life and stigma in PD patients. HRV emerges as a promising physiomarker for predicting and measuring the outcomes of psychological interventions in PD.

Mood and physiological effects of visual stimulation with images of the natural environment in individuals with depressive and anxiety disorders

BACKGROUND

Nature therapies are gaining attention as non-pharmacological treatments for depressive and anxiety disorders, but research on their effectiveness in patients is limited. This study investigates the mood-improving effects of visual stimulation with natural environmental images in patients with depressive and anxiety disorders.

METHODS

We conducted a randomized crossover comparison trial involving 60 right-handed adult participants with depressive or anxiety disorders and receiving outpatient treatment. Visual stimuli of natural environments consisted of green-themed nature images, while the control stimuli featured urban scenes dominated by buildings. The stimulation lasted for 3 min, during which orbital prefrontal brain activity was measured using a 2-channel Near-infrared Spectroscopy (NIRS) system, and heart rate variability was assessed using fingertip accelerated plethysmography.

RESULTS

Mood enhancement effects were observed in both the depressive and anxiety disorder groups following visual stimulation with nature images. In the depression group, orbital prefrontal oxygenated hemoglobin concentration significantly increased after visual stimulation with nature images, while there were no significant changes in the anxiety group. However, in the anxiety group, a correlation was found between reduced orbital prefrontal oxygenated hemoglobin in response to nature images and increased mood-enhancement. Furthermore, the severity of depressive symptoms did not significantly affect the intervention effects, whereas heightened anxiety symptoms was associated with a smaller mood enhancement effect.

DISCUSSION

Our study demonstrates the benefits of nature image stimulation for patients with depressive and anxiety disorders. Differential orbital prefrontal brain activity impacts notwithstanding, both conditions exhibited mood enhancement, affirming the value of nature image stimulation.

Dose-dependent response of prefrontal transcranial direct current stimulation on the heart rate variability: An electric field modeling study

Transcranial direct current stimulation (tDCS) of the prefrontal cortex (PFC) modulates the autonomic nervous system by activating deeper brain areas via top-down pathway. However, effects on the nervous system are heterogeneous and may depend on the amount of current that penetrates. Therefore, we aimed to investigate the variable effects of tDCS on heart rate variability (HRV), a measure of the functional state of the autonomic nervous system. Using three prefrontal tDCS protocols (1.5, 3 mA and sham), we associated the simulated individual electric field (E-field) magnitude in brain regions of interest with the HRV effects. This was a randomized, double-blinded, sham-controlled and within-subject trial, in which healthy young-adult participants received tDCS sessions separated by 2 weeks. The brain regions of interest were the dorsolateral PFC (DLPFC), anterior cingulate cortex, insula and amygdala. Overall, 37 participants were investigated, corresponding to a total of 111 tDCS sessions. The findings suggested that HRV, measured by root mean squared of successive differences (RMSSD) and high-frequency HRV (HF-HRV), were significantly increased by the 3.0 mA tDCS when compared to sham and 1.5 mA. No difference was found between sham and 1.5 mA. E-field analysis showed that all brain regions of interest were associated with the HRV outcomes. However, this significance was associated with the protocol intensity, rather than inter-individual brain structural variability. To conclude, our results suggest a dose-dependent effect of tDCS for HRV. Therefore, further research is warranted to investigate the optimal current dose to modulate HRV.

Are There Biological Correlates of Response to Yoga-Based Interventions in Depression? A Critical Scoping Review

Depression is the most common mental disorder worldwide. Both antidepressants and psychotherapy are effective in treating depression, but the response to these treatments is often incomplete. Yoga-based interventions (YBIs) have been advocated by some researchers as a promising form of alternative treatment for depression. Recent research has attempted to identify the biological mechanisms associated with the antidepressant actions of YBIs. In this scoping review, conducted according to the PRISMA-ScR guidelines, the PubMed and Scopus databases were searched to retrieve research on biomarkers of response to YBIs in patients with depression. These studies were also critically reviewed to evaluate their methodological quality and any sources of bias. Nineteen studies were included in the review. Based on these studies, there is preliminary evidence that YBIs may be associated with increased serum brain-derived neurotrophic factor (BDNF) and reduced serum cortisol and interleukin-6 (IL-6) in patients with depression. However, many of these changes were also observed in the control arms, and the overall quality of the research was low. At present, it cannot be concluded that there are reliable biomarkers of response to YBIs in depression, though there are some potential biological correlates. Further advances in this field will depend critically on improvements in study design, particularly the minimization of sources of bias and the selection of more specific and sensitive biomarkers based on existing evidence from other treatment modalities.

The relationship between emotional disorders and heart rate variability: A Mendelian randomization study

OBJECTIVE

Previous studies have shown that emotional disorders are negatively associated with heart rate variability (HRV), but the potential causal relationship between genetic susceptibility to emotional disorders and HRV remains unclear. We aimed to perform a Mendelian randomization (MR) study to investigate the potential association between emotional disorders and HRV.

METHODS

The data used for this study were obtained from publicly available genome-wide association study datasets. Five models, including the inverse variance weighted model (IVW), the weighted median estimation model (WME), the weighted model-based method (WM), the simple model (SM) and the MR-Egger regression model (MER), were utilized for MR. The leave-one-out sensitivity test, MR pleiotropy residual sum and outlier test (MR-PRESSO) and Cochran's Q test were used to confirm heterogeneity and pleiotropy.

RESULTS

MR analysis revealed that genetic susceptibility to broad depression was negatively correlated with HRV (pvRSA/HF) (OR = 0.380, 95% CI 0.146-0.992; p = 0.048). However, genetic susceptibility to irritability was positively correlated with HRV (pvRSA/HF, SDNN) (OR = 2.017, 95% CI 1.152-3.534, p = 0.008) (OR = 1.154, 95% CI 1.000-1.331, p = 0.044). Genetic susceptibility to anxiety was positively correlated with HRV (RMSSD) (OR = 2.106, 95% CI 1.032-4.299; p = 0.041). No significant directional pleiotropy or heterogeneity was detected. The accuracy and robustness of these findings were confirmed through a sensitivity analysis.

CONCLUSIONS

Our MR study provides genetic support for the causal effects of broad depression, irritable mood, and anxiety on HRV.

Meta-analysis on inflammation and autonomic nervous system of coronary heart disease combined with depression

OBJECTIVES

This meta-analysis aimed to explore the association between inflammatory factors, heart rate variability (HRV) and the coexistence of coronary heart disease (CHD) and depression.

DESIGN

Systematic review and meta-analysis. Complying with the Meta-analysis Of Observational Studies in Epidemiology statement.

DATA SOURCES

We searched PubMed, Web of Science and EMBASE for the data from the inception date to 16 March 2023.

ELIGIBILITY CRITERIA

We included cross-sectional and cohort studies with inclusion criteria: (1) patients with CHD; (2) depression measurement and (3) including inflammatory factors or cardiac biomarkers or HRV.

DATA EXTRACTION AND SYNTHESIS

Two authors searched the databases independently. The effect estimates and heterogeneity were synthesised by Review Manager V.5.3. Sensitivity analysis and publication bias were analysed by STATA software. The quantitative synthesis outcomes were presented by mean difference (MD) or standard MD (SMD) with 95% CI.

RESULTS

By searching the databases, we identified a total of 6750 articles. There were 22 articles left after selection, including 6344 participants. This meta-analysis indicated that patients with CHD with depression had higher levels of C reaction protein (CRP) (SMD 0.50, 95% CI (0.19 to 0.81), p=0.001), high-sensitivity C reactive protein (hs-CRP) (SMD 0.28, 95% CI (0.07 to 0.48), p=0.008), IL-6 (SMD 0.49, 95% CI (0.05 to 0.92), p=0.03) and a lower level of the mean RR interval and the SD of all RR intervals (SMD -0.64, 95% CI (-1.11 to -0.17), p=0.008), SD of the 5 min averages of all normal RR intervals (MD -12.77 ms, 95% CI (-21.20 to -4.33), p=0.003), overage of the SD of all normal RR intervals for each 5 min segment (MD -13.83 ms, 95% CI (-15.94 to -11.72), p<0.00001), root mean square of successive differences (MD: -8.02 ms, 95% CI (-13.62 to -2.43), p=0.005), proportion of adjacent cycles differing by >50 ms (pNN50) (SMD -0.86, 95% CI (-1.41 to -0.31), p=0.002), than those without depression.

CONCLUSIONS

This study underscores the association between elevated CRP, hs-CRP, IL-6 and lower HRV in patients with CHD with depression. It emphasises the importance of clinicians assessing CRP, hs-CRP, IL-6 and HRV in patients with CHD to potentially identify depressive conditions.

Emotion contagion and physiological synchrony: The more intimate relationships, the more contagion of positive emotions

The study aimed to explore how interpersonal closeness (friends vs. strangers) and emotion type (positive vs. negative) influenced emotion contagion and physiological synchrony between interacting partners. Twenty-eight friend dyads (n = 56) and 29 stranger dyads (n = 58) participated in an emotion contagion laboratory task. In each dyad, one participant, the 'sender', was randomly asked to watch a film clip (neutral, positive, or negative), while their partner, the 'observer' passively observed the sender's facial expressions. Participants' electrocardiograms (ECG) and facial electromyography (EMG) signals were recorded using the BIOPAC system. Results revealed that observing the sender's facial expressions led to the observer's spontaneous mimicry and emotional contagion, accompanied by enhanced physiological synchrony between interacting partners. In the positive emotion condition, the observers reported more positive emotions and displayed stronger zygomaticus major activity in friend dyads than in stranger dyads. Greater physiological synchrony (heart rate and heart rate variability) between interacting partners was also observed in friend dyads than in stranger dyads in the positive emotion condition. These results indicate that positive emotion contagion is more likely to occur between close partners than negative emotion contagion.

Neurobiological Underpinnings of Hyperarousal in Depression: A Comprehensive Review

Patients with major depressive disorder (MDD) exhibit an abnormal physiological arousal pattern known as hyperarousal, which may contribute to their depressive symptoms. However, the neurobiological mechanisms linking this abnormal arousal to depressive symptoms are not yet fully understood. In this review, we summarize the physiological and neural features of arousal, and review the literature indicating abnormal arousal in depressed patients. Evidence suggests that a hyperarousal state in depression is characterized by abnormalities in sleep behavior, physiological (e.g., heart rate, skin conductance, pupil diameter) and electroencephalography (EEG) features, and altered activity in subcortical (e.g., hypothalamus and locus coeruleus) and cortical regions. While recent studies highlight the importance of subcortical-cortical interactions in arousal, few have explored the relationship between subcortical-cortical interactions and hyperarousal in depressed patients. This gap limits our understanding of the neural mechanism through which hyperarousal affects depressive symptoms, which involves various cognitive processes and the cerebral cortex. Based on the current literature, we propose that the hyperconnectivity in the thalamocortical circuit may contribute to both the hyperarousal pattern and depressive symptoms. Future research should investigate the relationship between thalamocortical connections and abnormal arousal in depression, and explore its implications for non-invasive treatments for depression.

Cardiovascular variations in patients with major depressive disorder versus bipolar disorder

BACKGROUND

Differentiating depression in major depressive disorder and bipolar disorder is challenging in clinical practice. Therefore, reliable biomarkers are urgently needed to differentiate between these diseases. This study's main objective was to assess whether cardiac autonomic function can distinguish patients with unipolar depression (UD), bipolar depression (BD), and bipolar mania (BM).

METHODS

We recruited 791 patients with mood disorders, including 191 with UD, 286 with BD, and 314 with BM, who had been drug free for at least 2 weeks. Cardiovascular status was measured using heart rate variability (HRV) and pulse wave velocity (PWV) indicators via finger photoplethysmography during a 5-min rest period.

RESULTS

Patients with BD showed lower HRV but higher heart rates than those with UD and BM. The PWV indicators were lower in the UD group than in the bipolar disorder group. The covariates of age, sex, and body mass index affected the cardiovascular characteristics. After adjusting for covariates, the HRV and PWV variations among the three groups remained significant. Comparisons between the UD and BD groups showed that the variable with the largest effect size was the frequency-domain indices of HRV, very low and high frequency, followed by heart rate. The area under the receiver operating characteristic curve (AUC) for each cardiovascular variable ranged from 0.661 to 0.714. The High-frequency index reached the highest AUC.

LIMITATIONS

Cross-sectional design and the magnitude of heterogeneity across participants with mood disorders limited our findings.

CONCLUSION

Patients with BD, but not BM, had a greater extent of cardiac imbalance than those with UD. Thus, HRV may serve as a psychophysiological biomarker for the differential diagnosis of UD and BD.

Integrating Genome-wide information and Wearable Device Data to Explore the Link of Anxiety and Antidepressants with Heart Rate Variability

Background

Anxiety disorders are associated with decreased heart rate variability (HRV), but the underlying mechanisms remain elusive.

Methods

We selected individuals with whole-genome sequencing, Fitbit, and electronic health record data (N=920; 61,333 data points) from the All of Us Research Program. Anxiety PRS were derived with PRS-CS after meta-analyzing anxiety genome-wide association studies from three major cohorts-UK Biobank, FinnGen, and the Million Veterans Program (N Total =364,550). The standard deviation of average RR intervals (SDANN) was calculated using five-minute average RR intervals over full 24-hour heart rate measurements. Antidepressant exposure was defined as an active antidepressant prescription at the time of the HRV measurement in the EHR. The associations of daily SDANN measurements with the anxiety PRS, antidepressant classes, and antidepressant substances were tested. Participants with lifetime diagnoses of cardiovascular disorders, diabetes mellitus, and major depression were excluded in sensitivity analyses. One-sample Mendelian randomization (MR) was employed to assess potential causal effect of anxiety on SDANN.

Results

Anxiety PRS was independently associated with reduced SDANN (beta=-0.08; p=0.003). Of the eight antidepressant medications and four classes tested, venlafaxine (beta=-0.12, p=0.002) and bupropion (beta=-0.071, p=0.01), tricyclic antidepressants (beta=-0.177, p=0.0008), selective serotonin reuptake inhibitors (beta=-0.069; p=0.0008) and serotonin and norepinephrine reuptake inhibitors (beta=-0.16; p=2×10 -6 ) were associated with decreased SDANN. One-sample MR indicated an inverse effect of anxiety on SDANN (beta=-2.22, p=0.03).

Conclusions

Anxiety and antidepressants are independently associated with decreased HRV, and anxiety appears to exert a causal effect on HRV. Our observational findings provide novel insights into the impact of anxiety on HRV.