Vagally-mediated Heart Rate Variability Research Articles

Effects of stress management interventions on heart rate variability in adults with cardiovascular disease: a systematic review and meta-analysis.

Meta-analysis was used to investigate the potential benefits of stress management interventions (SMIs) on vagally-mediated heart rate variability (HRV) in adults with cardiovascular disease. Electronic bibliographic databases were searched through August 2022. Randomized controlled trials and quasi-experimental studies assessing effects of SMIs on HRV were included. Methodological quality was assessed with a standardized checklist. A pooled effect size was calculated for vagally-mediated HRV indices (standard deviation of normal-to-normal intervals, root mean square of the successive differences, and high frequency power) using random effects models. Fourteen studies (1202 participants, Mage: 59 ± 6.25years; 25% ± 16% women; 61% ± 22% White) were included. Ten studies (11 effects) reported short-term HRV assessment; a small between-group difference emerged for vagally-mediated HRV (d+ = .27, 95% confidence interval [CI] 0.01-0.52, k = 11). Most interventions examined biofeedback; these studies yielded a small between-group difference on vagally-mediated HRV (d+ = 0.31, 95% CI 0.09-0.53, k = 7, Q [6] = 3.82, p = .70, I2 = 11%). This is the first systematic examination of the effect of SMIs on HRV in adults with CVD. Findings suggest a small effect of SMIs on vagally-mediated HRV, with biofeedback likely driving the effect. More research is required to fully understand whether this benefit on vagally-mediated HRV applies to other SMIs.

481. Vagally-Mediated Heart Rate Variability Across the Menstrual Cycle and Its Association With Psychiatric Symptoms in Transdiagnostic Outpatients With Suicidality

481. Vagally-Mediated Heart Rate Variability Across the Menstrual Cycle and Its Association With Psychiatric Symptoms in Transdiagnostic Outpatients With Suicidality

The relationship between sustained attention and parasympathetic functioning

Sustained attention (SA) is an important cognitive ability that plays a crucial role in successful cognitive control. Resting vagally-mediated heart rate variability (vmHRV) has emerged as an informative index of parasympathetic nervous system activity and a sensitive correlate of individual differences in cognitive control. However, it is unclear how resting vmHRV is associated with individual differences in sustained attention. The primary aim of the current study was to assess if resting vmHRV was associated with individual differences in performance on a neuropsychological assessment of sustained attention. We further aimed to characterize the relationship between resting vmHRV and dispositional factors related to sustained attention, specifically attentional errors in daily life, self-regulation, mindfulness and media-multitasking. Based on previous work, we hypothesized higher resting vmHRV would be associated with better sustained attention across task-based and self-report measures. We did not find resting vmHRV to be significantly associated with performance measures on a task-based assessment of sustained attention. Further, resting vmHRV was not significantly associated with attention errors, self-regulation, mindfulness, or media-multitasking. This work stands to expand the current understanding between parasympathetic functioning, cognition, and behavior, investigating the unexplored domain of sustained attention and related dispositional factors.

Cerebral Hemodynamics and Vagally Mediated HRV Associated with High- and Low-frequency Yoga Breathing: An Exploratory, Randomized, Crossover Study

Abstract Background: Volitionally modifying respiration leads to changes in middle cerebral arterial (MCA) blood flow. The effect of changes in breath rate on MCA blood flow has not been reported. Aims and Objectives: To determine the effect of slow (bumblebee yoga breathing) and fast (high frequency yoga breathing) yoga breathing techniques on MCA blood flow and vagally mediated heart rate variability. Materials and Methods: Thirty participants (mean age ± standard deviation, 27.3 ± 4.2 years) were assessed on 2 separate days practicing either high frequency yoga breathing (HFYB, breath frequency 54.2/min) or slow frequency bumblebee yoga breathing (BBYB, breath frequency 3.8/min) in random order to determine the effects of changes in breath frequency on MCA hemodynamics. Assessments included transcranial Doppler sonography, vagally mediated heart rate variability (VmHRV), and respiration. Results: Both HFYB and BBYB (i) reduced MCA flow velocities, i.e., peak systolic, end diastolic, and mean flow velocities, and (ii) increased MCA pulsatility indices. There was an increase in VmHRV during BBYB based on increased power in high frequency (HF) and low frequency (LF). LF reflects VmHRV for slow breath frequencies. In BBYB the average breath rate was 3.8 breaths/min. In contrast, VmHRV decreased during HFYB (based on reduced HF power; repeated measures analysis of variance, P < 0.05, all cases). Conclusion: Hence, irrespective of the differences in breath frequency, both HFYB and BBYB appear to reduce MCA flow velocities and increase the resistance to blood flow bilaterally, although the VmHRV changed in opposite directions. MCA velocity and pulsatility changes are speculated to be associated with low global neural activity during yoga breathing.

Influence of Respiratory Frequency of Slow-Paced Breathing on Vagally-Mediated Heart Rate Variability.

Breathing techniques, particularly slow-paced breathing (SPB), have gained popularity among athletes due to their potential to enhance performance by increasing cardiac vagal activity (CVA), which in turn can help manage stress and regulate emotions. However, it is still unclear whether the frequency of SPB affects its effectiveness in increasing CVA. Therefore, this study aimed to investigate the effects of a brief SPB intervention (i.e., 5min) on CVA using heart rate variability (HRV) measurement as an index. A total of 75 athletes (22 female; Mage = 22.32; age range = 19-31) participated in the study, attending one lab session where they performed six breathing exercises, including SPB at different frequencies (5 cycles per minute (cpm), 5.5cpm, 6cpm, 6.5cpm, 7cpm), and a control condition of spontaneous breathing. The study found that CVA was significantly higher in all SPB conditions compared to the control condition, as indexed by both root mean square of the successive differences (RMSSD) and low-frequency HRV (LF-HRVms2). Interestingly, LF-HRVms2 was more sensitive in differentiating the respiratory frequencies than RMSSD. These results suggest that SPB at a range of 5cpm to 7cpm can be an effective method to increase CVA and potentially improve stress management and emotion regulation in athletes. This short SPB exercise can be a simple yet useful tool for athletes to use during competitive scenarios and short breaks in competitions. Overall, these findings highlight the potential benefits of incorporating SPB into athletes' training and competition routines.

Heart rate variability as a marker and predictor of inflammation, nosocomial infection, and sepsis - A systematic review.

The autonomic nervous system interacts with the immune system via the inflammatory response. Heart rate variability (HRV), a marker of autonomic activity, is associated with inflammation, and nosocomial infections/sepsis, and has clinical implications for the monitoring of at-risk patients. Due to the vagal tone's influence on anti-inflammatory immune response, this association may predominately be reflected by vagally-mediated HRV indices. However, HRV's predictive significance on inflammation/infection remains unclear. 843 studies examining the associations/prognostic value of HRV indices on inflammation, and nosocomial infection/sepsis were screened in this systematic review. According to inclusion and exclusion criteria, 68 associative studies and 14 prediction studies were included. HRV and pro-inflammatory state were consistently associated in healthy subjects and patient groups. Pro-inflammatory state was related to reduced total power HRV including vagally- and non-vagally-mediated HRV indices. Similar, compared to controls, HRV reductions were observed during nosocomial infections/sepsis. Only limited evidence supports the predictive value of HRV in the development of nosocomial infections/sepsis. Reduced very low frequency power HRV showed the highest predictive value in adults, even with different clinical conditions. In neonates, an increased heart rate characteristic score, combining reduced total power HRV, decreased complexity, and vagally-dominated asymmetry, predicted sepsis. Pro-inflammatory state is related to an overall reduction in HRV rather than a singular reduction in vagally-mediated HRV indices, reflecting the complex autonomic-regulatory changes occurring during inflammation. The potential benefit of using continuous HRV monitoring for detecting nosocomial infection-related states, and the implications for clinical outcome, need further clarification.

The moderating effect of resting heart rate variability on the relationship between internet addiction tendency and brain morphology.

Previous neuroimaging studies have investigated brain morphology associated with internet addiction tendency (IAT) in healthy subjects. However, whether resting vagally-mediated heart rate variability (HRV) exerting influences on the association of IAT and brain morphology remains unclear. This study used voxel-based morphometry (VBM) and multiple regression analyses to assess the interaction effect of IAT and resting vagally-mediated HRV on regional grey matter volumes in 82 healthy subjects. To further illustrate the observed interaction effect, the moderated hierarchical regression analysis was performed. The results showed that resting vagally-mediated HRV moderated the relationship between IAT scores and grey matter volume (GMV) in the precuneus and cerebellum. Specifically, individuals with higher resting vagally-mediated HRV showed a significant positive relationship between IAT scores and GMV in the precuneus, whereas individuals with lower resting vagally-mediated HRV showed a significant negative relationship between IAT scores and GMV in the precuneus. In addition, IAT scores were negatively correlated with GMV in the cerebellum among individuals with lower resting vagally-mediated HRV, but not among individuals with higher resting vagally-mediated HRV. These findings have demonstrated a moderating role of resting vagally-mediated HRV on the association of IAT and brain morphology.

Influence of physical post-exercise recovery techniques on vagally-mediated heart rate variability: A systematic review and meta-analysis.

In sports, physical recovery following exercise-induced fatigue is mediated via the reactivation of the parasympathetic nervous system (PNS). A noninvasive way to quantify the reactivation of the PNS is to assess vagally-mediated heart rate variability (vmHRV), which can then be used as an index of physical recovery. This systematic review and meta-analysis investigated the effects of physical recovery techniques following exercise-induced fatigue on vmHRV, specifically via the root mean square of successive differences (RMSSD). Randomized controlled trials from the databases PubMed, WebOfScience, and SportDiscus were included. Twenty-four studies were part of the systematic review and 17 were included in the meta-analysis. Using physical post-exercise recovery techniques displayed a small to moderate positive effect on RMSSD (k = 22, Hedges' g = 0.40, 95% confidence interval [CI] = 0.20-0.61, p = 0.04) with moderate heterogeneity. In the subgroup analyses, cold water immersion displayed a moderate to large positive effect (g = 0.75, 95% CI: 0.42-1.07) compared with none for other techniques. For exercise type, physical recovery techniques performed after resistance exercise (g = 0.69, 95% CI: 0.48-0.89) demonstrated a larger positive effect than after cardiovascular intermittent (g = 0.52, 95% CI: 0.06-0.97), while physical recovery techniques performed after cardiovascular continuous exercise had no effect. No significant subgroup differences for training status and exercise intensity were observed. Overall, physical post-exercise recovery techniques can accelerate PNS reactivation as indexed by vmHRV, but the effectiveness varies with the technique and exercise type.

Leveraging Vagally Mediated Heart Rate Variability as an Actionable, Noninvasive Biomarker for Self-Regulation: Assessment, Intervention, and Evaluation

This contribution highlights the significance of using vagally-mediated heart rate variability (vmHRV), a general indicator of adaptation, as an actionable biomarker to assess and enhance self-regulation abilities in individuals and organizations. The paper reviews the state-of-the-art on vmHRV and introduces various techniques to enhance vmHRV, including slow-paced breathing, the diving reflex, transcutaneous vagus nerve stimulation (tVNS), transcranial magnetic stimulation (TMS), and transcranial direct current stimulation (tDCS). The recommendations for policymaking are based on recent systematic reviews and meta-analyses related to the implementation of these techniques in diverse settings, such as clinical, organizational, and educational contexts. The discussion emphasizes the efficacy, accessibility, and cost-effectiveness of vmHRV assessments and offers practical tools for individuals and organizations through a three-part framework—assessment, intervention, and evaluation—ultimately fostering self-regulation abilities at both individual and societal levels.

Vagally-mediated HRV as a marker of trait rumination in healthy individuals? A large cross-sectional analysis.

The tendency to ruminate (i.e., repetitive, self-referential, negative thoughts) is a maladaptive form of emotional regulation and represents a transdiagnostic vulnerability factor for stress-related psychopathology. Vagally-mediated heart rate variability (vmHRV) provides a non-invasive, surrogate measure of vagal modulation of the heart, and higher HRV is considered an indicator of susceptibility, or ability to respond to stress. Past research has suggested a link between trait rumination and vmHRV; however, inconsistent results exist in healthy individuals. In this study, we investigated the association between the tendency to ruminate, brooding, and reflection (using the Ruminative Response Scale) with vmHRV measured at baseline in a healthy population using a large cross-sectional dataset (N = 1189, 88% female; mean age = 21.55, ranging from 17 to 48 years old), which was obtained by combining samples of healthy individuals from different studies from our laboratory. The results showed no cross-sectional correlation between vmHRV and trait rumination (confirmed by Bayesian analysis), even after controlling for important confounders such as gender, age, and depressive symptoms. Also, a non-linear relationship was rejected. In summary, based on our results in a large sample of healthy individuals, vmHRV is not a marker of trait rumination (as measured by the Ruminative Response Scale).

Exhaustion and cardiovascular risk factors: the role of vagally-mediated heart rate variability

PurposeExhaustion symptoms are known to be associated with cardiovascular disease (CVD) risk; however, the underlying mechanisms remain unclear. Autonomic imbalance, as indicated by reductions in vagally-mediated heart rate variability (vmHRV), appears to be a valid candidate for such a biological link, as it has been associated with both exhaustion symptoms and CVD risk and mortality. MethodsThe present study examined a potential mediation of vmHRV on the association between exhaustion symptoms and self-reported CVD risk factors as well as the age dependency of this mediation in a large, heterogeneous sample of the Dresden Burnout Study (N = 388; 72.9% females; Mage = 42.61, SD = 11.67). ResultsResults indicate that exhaustion symptoms were indirectly associated with CVD risk factors through vmHRV even after adjusting for well-known confounders (i.e., sex, body mass index, depressive symptoms). Moreover, this pattern was significant only among middle-aged (i.e., 54.27 years) and older individuals. ConclusionsOur findings add to growing evidence that autonomic imbalance may be a key biological link between exhaustion symptoms and CVD risk in middle-aged and older individuals. Implications for public health are discussed.

Baseline heart rate variability predicts placebo hypoalgesia in men, but not women.

Placebo hypoalgesic effects vary greatly across individuals, making them challenging to control for in clinical trials and difficult to use in treatment. We investigated the potential of resting vagally-mediated heart rate variability (vmHRV) to help predict the magnitude of placebo responsiveness. In two independent studies (total N = 77), we administered a placebo paradigm after measuring baseline HRV. In Study I, we delivered heat pain to the forearm, on skin patches treated with "real" and "control" cream (identical inactive creams). In Study II, electrical pulses to the forearm were modulated by sham transcutaneous electrical nerve stimulation. We combined data from both studies to evaluate the relationship between vagally-mediated HRV (vmHRV) parameters and the placebo response size, while also assessing sex differences in this relationship. This revealed a positive association between vmHRV and the degree of pain relief, and this effect was driven by men. These results not only reveal new insights into the (sex-specific) mechanisms of placebo hypoalgesia, but also suggest that measuring vmHRV may be helpful in predicting placebo responsiveness. Given that placebo hypoalgesic effects contribute substantially to treatment outcomes, such a non-invasive and easily obtained predictor would be valuable in the context of personalized medicine.

Mindfulness-Based Intervention Effect on the Psychophysiological Marker of Self-Regulation in Women With Endometriosis-Related Chronic Pain

Endometriosis is a gynecological disease that involves a broad biopsychosocial compromise with the potential to create a negative vicious cycle. Despite the complexity of factors influencing women's improvement, most interventions investigated target just the peripheral nociceptive sources of endometriosis-related pain. An alternative is intervening in self-regulation, which can potentially influence multiple domains of the illness experience. The present study examines the effect of a brief Mindfulness-Based Intervention (bMBI) on attention and autonomic nervous system regulation in women with endometriosis-related pain. Also, explore the interaction between these self-regulation domains and the affective pain dimension. An exploratory analysis of the secondary outcomes of a pilot randomized controlled trial was performed. The vagally-mediated Heart Rate Variability (vmHRV) at rest, cognitive stress, and recovery was employed to measure autonomic regulation. The Flanker and Stroop tasks were used to estimate the attention domains. Results showed that bMBI (n = 26) significantly improved Flanker accuracy and Flanker and Stroop reaction time compared to the control group (n = 28). bMBI significantly increased vmHRV at rest and recovery after cognitive stress. Attention mediated the bMBI effect on affective pain improvement. Results suggest that bMBI improves self-regulation domains with the potential to develop a broad biopsychosocial benefit in the endometriosis context. PerspectiveThis article demonstrates the positive impact of a brief Mindfulness-Based Intervention on attention and parasympathetic regulation in women suffering from endometriosis-related pain. This mindfulness-induced self-regulation improvement can benefit affective pain and potentially multiple psychophysiological processes relevant to endometriosis.

The increase in vagally-mediated heart rate variability mediates treatment effects of exercise on global symptom severity across diagnostically heterogenous mental disorders: A secondary analysis of the ImPuls trial

BackgroundThe reduced ability to adaptively respond to stressors (coping) has been proposed as an underlying mechanism across psychopathology. It is associated with a reduced vagally-mediated heart rate variability (vmHRV) at rest and increased perceived stress. The present study investigated the increase in vmHRV and the reduction in perceived stress as potential mediators of the previously demonstrated intervention effect of exercise on global symptom severity across diagnostically heterogeneous mental disorders. MethodsSedentary outpatients with depressive disorders, anxiety disorders, insomnia and attention deficit hyperactivity disorder were randomly assigned to a 12-week standardized exercise intervention (n = 38) or passive control condition (n = 36). Baseline and post-treatment assessments included measures of global symptom severity (Symptom Checklist-90), resting vmHRV (root mean square of successive differences between normal heartbeats), and perceived stress (Perceived Stress Scale). Intention-to-treat analyses were conducted using linear mixed models and structural equations modeling. ResultsAmong the intervention group, resting vmHRV increased significantly (d = 0.87, p = .003) but perceived stress did not show a significant reduction (d = −0.32, p = .267) compared to the control group. The increase in vmHRV partially mediated the intervention effect on global symptom severity (ß = −0.05, p = .013). ConclusionThe study results provide evidence that an increase in vmHRV potentially acts as a partial mediator for the beneficial effects of exercise interventions on symptoms across individuals with mental disorders who may have a diminished ability to cope with stressors.

Menstrual cycle, heart rate variability (HRV), and mood: Is cyclicity of HRV associated with cyclicity of mood symptoms?

In an effort to understand potential biological indices of menstrually-related mood changes experienced by some naturally cycling individuals, we previously investigated whether vagally-mediated HRV (i.e., a biomarker of physical and mental health) fluctuates across the menstrual cycle. Our recent meta-analysis revealed a significant decrease of HRV in the midluteal phase which, as two-follow up studies suggest, is correlated with progesterone. However, the question remains whether cyclicity of HRV is associated with cyclicity of mood symptoms. Fifty naturally-cycling participants (M=24.8 years, SD=5.8) were examined (10-min baseline EKG for HRV assessment, PANAS for mood assessment) in three precisely determined cycle phases (ovulatory, midluteal, menstrual) via ovulation testing. To test the idea that degree of midluteal (vs. menstrual phase) HRV suppression is associated with the degree of PANAS same-day mood deterioration in the midluteal phase (vs. menstrual phase), each person’s difference score in HRV between the two phases was assessed. This between-person factor was taken into multilevel models predicting PANAS items from menstrual cycle phase. Analyses revealed that greater midluteal phase suppression of HRV was associated with greater midluteal phase increases in distress, as well as several fear and anxiety variables. No differences in sadness or irritability were found. These findings suggest that cyclical HRV suppression and cyclical increase in mood symptoms tend to covary. Further work is needed to clarify whether cyclicity of HRV may serve as a biological index of menstrually-related mood disorders.

Heart rate variability during social interaction: Effects of valence and emotion regulation

Conceptual models of psychosocial influences on short-term changes (i.e., reactivity) in vagally-mediated heart rate variability (vmHRV) emphasize self-regulatory effort and social threat versus comfort. However, these two general perspectives have been tested separately in nearly all cases, limiting conclusions about the relative importance or possible interactive effects of effortful self-regulation and social stress. The present study compared effects of effort to regulate emotional expression and social stress versus safety on vmHRV reactivity during an interpersonal interaction, in a 2 (self-regulate emotion vs. express emotion freely) × 3 (positive vs. neutral vs. negative interaction valence) × 2 (male vs. female) between-subjects randomized factorial design. A sample of 180 undergraduates (90 women; 69 % White) discussed a current events topic (i.e., human-caused climate change) with a prerecorded partner, presented as a live interaction over a computer. Self-reports of affective responses, self-regulation effort, and appraisals of the partner's behavior, as well as observer ratings of participants' behavior during the interaction, supported the effectiveness of self-regulation and interaction valence manipulations, although the former manipulation may have been somewhat weaker than the latter. Primary analyses of high-frequency heart rate variability (HF-HRV) and root mean square of successive differences (RMSSD) in heart beat intervals recorded at baseline and during the interaction revealed larger decreases in vmHRV during negative than neutral or positive interactions, but no effects of self-regulation instructions. Overall, results indicated more robust effects of social stress on vmHRV reactivity, relative to effects of self-regulatory effort.

Sex differences in heart rate and heart rate variability in rats: Implications for translational research.

The present study aimed to investigate sex differences in measures of cardiac chronotropy and heart rate variability (HRV) in 132 young adult wild-type Groningen rats (n = 45 females). Electrocardiographic signals were recorded for 48h in freely moving rats to quantify heart rate (HR) and inter-beat interval (IBI) as measures of cardiac chronotropy, and time- and frequency-domain HRV parameters as physiological readouts of cardiac vagal modulation. Females showed greater vagally-mediated HRV despite having higher HR and shorter IBI than males during undisturbed conditions. Such differences were evident i) at any given level of HRV, and ii) both during the 12-h light/inactive and 12-h dark/active phase of the daily cycle. These findings replicate the paradoxical cardiac chronotropic control reported by human meta-analytic findings, since one would expect greater vagally-mediated HRV to be associated with lower HR and longer IBI. Lastly, the association between some HRV measures and HR was stronger in female than male rats. Overall, the current study in young adult rats provides data illustrating a sex-dependent association between vagally-mediated HRV and indexes of cardiac chronotropy. The current results i) are in line with human findings, ii) suggest to always consider biological sex in the analysis and interpretation of HRV data in rats, and iii) warrant the use of rats for investigating the neuro-hormonal basis and temporal evolution of the impact of sex on the association between vagally-mediated HRV and cardiac chronotropy, which could inform the human condition.

Physiological stress reactivity and recovery: Some laboratory results transfer to daily life.

Stress is a prevalent theme in our daily lives and is related to numerous negative health outcomes. Laboratory research has studied the physiological stress response extensively with objective measures such as vagally-mediated heart rate variability (vmHRV). Recently, the vagal tank theory emerged as a promising approach to predicting adaptive vmHRV levels around stressful events. This study aimed to investigate whether the predictions of the vagal tank theory about vmHRV during stress reactivity and recovery translate into naturalistic stressful events in daily life. Sixty-seven students wore an EcgMove 4 sensor for 4 days to measure vmHRV. Through a combination of device-based and self-report assessment, vmHRV data were segmented into before, during, and after stressful events. VmHRV segments were analyzed with multilevel modeling, accounting for physiological and psychological covariates. VmHRV before stressful events predicted more adaptive vmHRV during the event but not vmHRV recovery afterwards. The results therefore partially support the vagal tank theory's predictions with data from daily life and allow recommendations for future studies of real-world stress reactivity and recovery. The value of intraindividual variations in vmHRV as predictors of adaptive stress response is underscored by these findings and could inform future interventions that seek to increase momentary vmHRV.

A scoping review of heart rate variability in sport and exercise psychology

ABSTRACT Sport and Exercise Psychology (SEP) often adopts physiological markers in theory and practice, and one measure receiving increasing attention is heart rate variability (HRV). This paper aimed to provide a scoping review of the use of HRV within SEP. The protocol was made available on the Open Science Framework. Study inclusion criteria were examination of HRV in SEP, using athletes or healthy populations, peer-reviewed and published in English. Exclusion criteria were non-peer reviewed work, animal studies, clinical populations, review or conference papers. In February 2022 a systematic search of Web of Science, PubMed and Sport Discus identified 118 studies (4979 participants) using HRV in sport psychology (71) or exercise psychology (47). Risk of bias was assessed via the Mixed Methods Appraisal Tool. A narrative synthesis revealed that HRV was assessed within a range of topics such as stress, overtraining, anxiety, biofeedback, cognitive performance, and sporting performance. Three key limitations within the field were discovered: limited application of theoretical frameworks, methodological issues with HRV measurement, and differing interpretations of HRV results. Future research should use vagally-mediated HRV as a marker of self-regulation and adaptation in SEP, consult relevant HRV theories prior to hypothesis development, and follow methodological guidelines for HRV.

Early indicators of vulnerability to depression: The role of rumination and heart rate variability

BackgroundDespite the evidence of increased levels of rumination and reduced heart rate variability (HRV) in depression, whether these measures can be considered early indicators of vulnerability to depression has yet to be investigated. Therefore, the present study aimed to investigate both levels of rumination and resting HRV in individuals with familial risk for depression that is the most reliable risk factor for the disorder. MethodsRumination and vagally-mediated HRV were assessed using the Ruminative Response Scale and a smartphone-based photoelectric volumetric pulse wave assay, respectively, in 25 individuals who had family history of depression (but did not report current depressive symptoms), 15 individuals who reported depressive symptoms (but had no family history of depression), and 25 controls (without depressive symptoms and family history of depression). Results: Individuals with depressive symptoms and those with a family history of depression were characterized by higher levels of rumination and lower cardiac vagal control than controls. LimitationsGiven the small sample size, this study should be used to design larger confirmatory studies; the cross-sectional nature of the study does not allow discussing the results in terms of cause-effect relationships. ConclusionsOur findings suggested that individuals at risk of developing depression, also in absence of depressive symptoms, are defined by defective self-regulation capacity that may lead to future depression episodes. Increased ruminative thoughts and reduced HRV may represent early indicators of vulnerability to depression. Effective prevention programs designed to reduce rumination and/or increase HRV may reduce the risk of developing a full-blown depressive episode.