Is diurnal variation of mood associated with parasympathetic activity?

Acupuncture for Combat-Related Posttraumatic Stress Disorder: A Randomized Clinical Trial

Importance

Current interventions for posttraumatic stress disorder (PTSD) are efficacious, yet effectiveness may be limited by adverse effects and high withdrawal rates. Acupuncture is an emerging intervention with positive preliminary data for PTSD.

Objective

To compare verum acupuncture with sham acupuncture (minimal needling) on clinical and physiological outcomes.

Design, Setting, and Participants

This was a 2-arm, parallel-group, prospective blinded randomized clinical trial hypothesizing superiority of verum to sham acupuncture. The study was conducted at a single outpatient-based site, the Tibor Rubin VA Medical Center in Long Beach, California, with recruitment from April 2018 to May 2022, followed by a 15-week treatment period. Following exclusion for characteristics that are known PTSD treatment confounds, might affect biological assessment, indicate past nonadherence or treatment resistance, or indicate risk of harm, 93 treatment-seeking combat veterans with PTSD aged 18 to 55 years were allocated to group by adaptive randomization and 71 participants completed the intervention protocols.

Interventions

Verum and sham were provided as 1-hour sessions, twice weekly, and participants were given 15 weeks to complete up to 24 sessions.

Main Outcomes and Measures

The primary outcome was pretreatment to posttreatment change in PTSD symptom severity on the Clinician-Administered PTSD Scale-5 (CAPS-5). The secondary outcome was pretreatment to posttreatment change in fear-conditioned extinction, assessed by fear-potentiated startle response. Outcomes were assessed at pretreatment, midtreatment, and posttreatment. General linear models comparing within- and between-group were analyzed in both intention-to-treat (ITT) and treatment-completed models.

Results

A total of 85 male and 8 female veterans (mean [SD] age, 39.2 [8.5] years) were randomized. There was a large treatment effect of verum (Cohen d, 1.17), a moderate effect of sham (d, 0.67), and a moderate between-group effect favoring verum (mean [SD] Δ, 7.1 [11.8]; t90 = 2.87, d, 0.63; P = .005) in the intention-to-treat analysis. The effect pattern was similar in the treatment-completed analysis: verum d, 1.53; sham d, 0.86; between-group mean (SD) Δ, 7.4 (11.7); t69 = 2.64; d, 0.63; P = .01). There was a significant pretreatment to posttreatment reduction of fear-potentiated startle during extinction (ie, better fear extinction) in the verum but not the sham group and a significant correlation (r = 0.31) between symptom reduction and fear extinction. Withdrawal rates were low.

Conclusions and Relevance

The acupuncture intervention used in this study was clinically efficacious and favorably affected the psychobiology of PTSD in combat veterans. These data build on extant literature and suggest that clinical implementation of acupuncture for PTSD, along with further research about comparative efficacy, durability, and mechanisms of effects, is warranted.

Trial Registration

ClinicalTrials.gov Identifier: NCT02869646.

Positive affect and parasympathetic activity: Evidence for a quadratic relationship between feeling safe and content and heart rate variability

There has been an increased interest in the study of underlying autonomic correlates of emotions. This study tests the hypothesis that high levels of high-frequency heart rate variability (HF HRV) are associated with positive emotions. In addition, we hypothesize that this association will differ according to the type of positive emotion. Also, based on recent findings, we tested the hypothesis that this relationship would be nonlinear. Resting-state HRV was collected and self-report measures of different positive emotions were administered to a sample of 124 volunteers.

RESULTS

Results suggested that there was a quadratic relationship between high-frequency heart rate variability and positive emotions associated with safeness and contentment, but not with positive emotions associated with excitement or lack of arousal. Our data suggests that different positive emotions may be characterized by qualitatively distinct profiles of autonomic activation. Also, given the role of positive emotions in social affiliation, and particularly positive emotions associated with a quiescence motivational state, results are interpreted in light of theoretical accounts that highlight the importance of vagal regulation for social behavior.

The variable heart: High frequency and very low frequency correlates of depressive symptoms in children and adolescents

BACKGROUND

Work examining the link between lower heart rate variability (HRV) and depression in children and adolescents is lacking, especially in light of the physiological changes that occur during pubertal development.

METHOD

We investigated the association between spectral measures of resting HRV and depressive symptoms among 127 children and adolescents, ages 10-17. Using spectral analysis, we evaluated (1) the association between relative high frequency (HF) HRV and depressive symptoms; (2) the predictive power of relative HF HRV for depressive symptoms in the context of relative low frequency (LF) and relative very low frequency (VLF) HRV; and (3) the relationship between relative HF, LF, and VLF band activity, age and pubertal maturation.

RESULTS

Consistent with previous work, results revealed that relative HF HRV was negatively associated with self-reported depressive symptoms. As well, relative VLF HRV was positively associated with depressive symptoms. Regression analyses revealed that relative HF HRV and relative VLF HRV significantly predicted self-report depressive symptoms while controlling for age, sex and pubertal maturation, with relative VLF HRV emerging as the strongest indicator of depressive symptoms. Developmental findings also emerged. Age and pubertal maturation were negatively associated with relative HF HRV and positively correlated with relative VLF HRV.

CONCLUSIONS

Results provide support for the relationship between HRV and depression and suggest that both HF and VLF HRV are relevant to depression symptom severity. Findings also reinforce the importance of considering pubertal development when investigating HRV-depression associations in children and adolescents.

LIMITATIONS

Influences on cardiac control including physical activity levels and exercise patterns could be controlled in future work. Our data speak to a depressive symptom dimension and relative spectral power HRV. Thus, we cannot make strong claims about relative spectral power HRV and clinical depression.

Bright light therapy for depression: a review of its effects on chronobiology and the autonomic nervous system

Bright light therapy (BLT) is considered among the first-line treatments for seasonal affective disorder (SAD), yet a growing body of literature supports its use in other neuropsychiatric conditions including non-seasonal depression. Despite evidence of its antidepressant efficacy, clinical use of BLT remains highly variable internationally. In this article, we explore the autonomic effects of BLT and suggest that such effects may play a role in its antidepressant and chronotherapeutic properties. After providing a brief introduction on the clinical application of BLT, we review the chronobiological effects of BLT on depression and on the autonomic nervous system in depressed and non-depressed individuals with an emphasis on non-seasonal depression. Such a theory of autonomic modulation via BLT could serve to integrate aspects of recent work centered on alleviating allostatic load, the polyvagal theory, the neurovisceral integration model and emerging evidence on the roles of glutamate and gamma-hydroxybutyric acid (GABA).

Acupuncture for posttraumatic stress disorder: conceptual, clinical, and biological data support further research

Posttraumatic stress disorder (PTSD) is common, debilitating, and has highly heterogeneous clinical and biological features. With the exception of one published preliminary clinical trial, rationale in support of the efficacy of acupuncture, a modality of Chinese medicine (CM), for PTSD has not been well described. This is a focused review of conceptual and clinical features of PTSD shared by modern western medicine (MWM) and CM, and of biological mechanisms of acupuncture that parallel known PTSD pathology. MWM and CM both recognize individual developmental variables and interactions between external conditions and internal responses in the genesis of PTSD. There is one published and one unpublished clinical trial that preliminarily support the efficacy of acupuncture for PTSD. Although there have been no mechanistic studies of acupuncture in human PTSD, extant research shows that acupuncture has biological effects that are relevant to PTSD pathology. Conceptual, clinical, and biological data support possible efficacy of acupuncture for PTSD. However, further definitive research about simultaneous clinical and biological effects is needed to support the use of acupuncture for PTSD in health care systems.

Trait negative affect: toward an integrated model of understanding psychological risk for impairment in cardiac autonomic function

OBJECTIVE

To assess depression, anxiety, and anger as well as the variance that these emotions share (conceptualized as negative affect) in relationship to high-frequency heart rate variability (HF-HRV), a specific indicator of parasympathetic cardiac autonomic function related to premature cardiovascular morbidity and mortality. Although individual trait negative emotions have been studied in relation to risk for coronary heart disease (CHD) as well as biological mechanisms leading to CHD end points (e.g., autonomic nervous system [ANS] dysfunction), the degree to which a general tendency to experience negative emotions may account for these relations is not known.

METHODS

The sample included 653 community volunteers (51.0% female; 15.8% Black) aged 30 to 54 years (mean +/- standard deviation = 43.8 +/- 7.1 years). Latent constructs of depression, anxiety, and anger were each measured by three scales from well-validated self-report questionnaires. Resting HF-HRV was derived from 5-minute segments of continuous electrocadiographs recorded during both unpaced and paced respiration conditions.

RESULTS

Structural equation models (SEM) of the individual trait emotions showed depression and anxiety related inversely to HF-HRV and anger unrelated to HF-HRV. SEM also showed negative affect related inversely to HF-HRV. All associations were present after covariate adjustment for traditional cardiovascular risk factors, including age, sex, race, education, body mass index, smoking status, and blood pressure.

CONCLUSIONS

Negative affect as a common pathway between depression, anxiety, and anger and impairments in cardiac autonomic function was supported, suggesting negative affect may be the unifying and potentially toxic element linking individual trait negative emotions to ANS dysregulation.

Diurnal variation in regional brain glucose metabolism in depression

BACKGROUND

This study compared diurnal variation in mood and regional cerebral metabolic rate of glucose (rCMRglc) in depressed and healthy subjects.

METHODS

Depressed and healthy subjects were investigated using [18F]-fluoro-deoxyglucose positron emission tomography scans during morning and evening wakefulness. All subjects completed subjective mood ratings at both times of day. Statistical parametric mapping was used to compare rCMRglc between the two groups across time of day.

RESULTS

Depressed patients showed evening mood improvements compared with healthy subjects. Compared with healthy subjects, depressed patients showed smaller increases in rCMRglc during evening relative to morning wakefulness in lingual and fusiform cortices, midbrain reticular formation, and locus coeruleus and greater increases in rCMRglc in parietal and temporal cortices. Depressed patients had hypermetabolism in limbic-paralimbic regions and hypometabolism in frontal and parietal cortex at both times of day compared with healthy subjects.

CONCLUSIONS

Variation in rCMRglc differs across times of day in depressed and healthy subjects. In depressed patients, evening mood improvements were associated with increased metabolic activity in ventral limbic-paralimbic, parietal, temporal, and frontal regions and in the cerebellum. This increased metabolic pattern during evening wakefulness may reflect partial normalization of primary and compensatory neural systems involved in affect production and regulation.

Sex differences in cardiac vagal control in a depressed sample: implications for differential cardiovascular mortality

Previous studies suggest depression is a risk factor for all cause mortality, with depressed men at greater risk than depressed women. Diminished cardiac vagal control (CVC) in depressed patients has also been found to increase risk of cardiac mortality. Previous research found that depressed women have higher CVC than depressed men suggesting CVC might be related to the discrepancy in mortality rates between depressed men and women. This finding, however, was in the context of a study with several methodological weaknesses. The current study sought to replicate the sex difference in CVC in a sample of 137 medically healthy and clinically diagnosed depressed patients. Main effects of sex and age significantly predicted CVC such that depressed women had greater CVC and CVC decreased with age in the cross-sectional sample. The results suggest greater CVC in depressed women might confer cardioprotective functions, which may partially explain the sex difference in mortality rates in the depressed population.

Cardiac vagal control in depression: a critical analysis

Rapidly developing research has found abnormal cardiac vagal control (CVC) in several physical and mental health conditions. CVC findings in depression are mixed, and the degree to which CVC is compromised in depression is unclear. A meta-analysis of 13 rigorous cross-sectional studies reveals that a diagnosis of depression exerts a small-to-medium effect size on CVC, and explains only about 2% of the overall variance in CVC. More robust data may emerge from alternative approaches to the depression-CVC relationship, such as the use of CVC to predict the course of the disorder. Despite the vigor of recent work on CVC and depression, overall findings are suggestive rather than conclusive. Methodological desiderata and priorities for future research are discussed, including the need to clarify the etiological significance of CVC.

Cardiac Vagal Tone, defensiveness, and motivational style

Cardiac Vagal Tone has been proposed as a stable biological marker for the ability to sustain attention and regulate emotion [Porges, Monographs of the Society for Research in Child Development 59 (1994) 167-186]. Vagal tone is a physiological index of parasympathetic nervous system influence on the heart that has predicted a number of emotional behaviors and styles in infants, children, and adults. Little research, however, has sought to explore the link between vagal tone and established variables relating to personality and self-regulation. In this study, vagal tone was collected during 5-min baseline, stress, and recovery periods. Subjects (n = 98) also completed a short form of the Marlowe-Crowne Social Desirability Scale, the Behavioral Activation and Behavioral Inhibition Scales, the Taylor Manifest Anxiety Scale, the Self-Consciousness Scale, and the Openness to Experience subscale of the Five Factor Personality Inventory. Poorer modulation for vagal tone was associated with greater social anxiety, while lower vagal tone across recording periods was associated with greater defensiveness and lower behavioral activation sensitivity.

Resting RSA is associated with natural and self-regulated responses to negative emotional stimuli

Resting respiratory sinus arrhythmia (RSA) was assessed among 111 adult participants. These individuals were then asked to watch a positive or negative affective film in either a natural manner or while exaggerating their facial response. Facial reactions to the film were video-recorded and subsequently rated in terms of facial affect. Participants also self-reported the valence of their emotional experience. Results from regression analyses revealed that persons with low resting RSA behaviorally evidenced a more negative facial response to the negative film under natural-watch conditions. Low RSA individuals were also less able to modulate (i.e., amplify) their facial response to the negative film. In terms of self-report measures, persons in the exaggerate condition reported more positive affect to the positive film than did those in the natural-watch condition. Results suggest that cardiac vagal control is inversely associated with negative facial expression but positively associated with facial regulation ability to negative stimuli.

Reduced sympathetic outflow and adrenal secretory activity during a 40-day stay in the Antarctic

Human adaptation to unknown and extreme environments requires changes in the psychological and physical homeostasis. We previously reported a significant decrease of anterior pituitary and adrenal hormonal levels and a significant modification of psychophysiological correlates of stress, such as galvanic skin response, after exposure to Antarctica, suggesting a possible decrease of individual arousal. The latter was hypothesized to be correlated with a modification of autonomic balance, mainly represented by a possible reduction of adrenergic output. The aim of the present study was to assess the patterns of hormonal circadian rhythms and the autonomic nervous system balance by means of spectral analysis of heart rate variability (HRV). These parameters were evaluated during 3 sessions (baseline, session 1 and session 2), before, at the beginning and after a 40-day stay in Antarctica (Station of Terra Nova Bay; average temperature in the study period: -11 degrees C, 24 h of light, sea level). In each of the sessions, 6 healthy male subjects underwent a 24-h electrocardiogram and blood sampling (08.00, 12.00, 16.00, 20.00, 24.00 and 08.00 h) for hormonal determinations. The data showed a remarkable decrease of hormonal levels without significant changes in circadian rhythms. Spectral analysis of HRV showed an imbalance of the autonomic nervous system with a relative significant decrease of the low frequency band (0.1 Hz) in session 1 and 2 compared to baseline, which can be functionally interpreted as a relative decrement of the sympathetic component. In conclusion, the exposure to a cold and extreme environment seems to affect autonomic balance over a 40-day period. This is followed by a significant reduction of the anterior pituitary and adrenal hormonal secretory patterns with preserved hormonal circadian rhythms (within the same time period of 40 days). This pattern is suggestive of a trophotropic neurovegetative adaptive process.

A comparison of self-reports of distress and affective disorder diagnoses in rheumatoid arthritis: a receiver operator characteristic analysis

OBJECTIVE

To compare 3 commonly used psychiatric symptom checklists (the Center for Epidemiological Studies Depression Scale [CES-D], the Positive and Negative Affect Schedule, and the Endler Multidimensional Anxiety Scales [EMAS]) to determine their sensitivity, specificity, and ability to discriminate between a disorder (Major Depression [MD], Generalized Anxiety Disorder [GAD]), and no disorder. To compare the checklists for their ability to discriminate between type of disorder (MD and GAD). To evaluate the discriminant ability of the subscales, particularly positive affect; whether the somatic items in the CES-D artificially inflate affective scores; and the optimal cut off score for the CES-D.

METHODS

We compared the 3 scales to diagnostic criterion of MD, GAD, and comorbid disorder using receiver operator characteristic (ROC) and logistic regression analyses. The sample consisted of a national panel of 415 individuals with rheumatoid arthritis (RA).

RESULTS

Each of the scales had high sensitivity and specificity (areas under the curve: CES-D = 0.92, negative affect = 0.88, positive affect and EMAS = 0.82). The CES-D, however, demonstrated better sensitivity and specificity than the positive affect and the EMAS, but not the negative affect scale.

CONCLUSION

All 3 self-reports have high combined sensitivity and specificity as measures of affective disorders among RA patients.

Autonomic and emotion regulation in bereavement and depression

OBJECTIVES

Prior research suggests important differences between depression and the depressed feelings experienced in the context of bereavement, despite some overlap. Differences include an increase in restlessness, suggesting underlying physiological differences between the groups.

METHOD

This study examined the level of depressive symptoms, heart rate (HR), and heart rate variability (HRV), and coping style of 10 bereaved, 10 depressed, and 10 control participants.

RESULTS

Bereaved participants showed significantly higher HR than either depressed or control participants, while there were no such differences in HRV. Level of depression in the bereaved group correlated negatively with HRV. Additional analyses showed that the use of passive coping had a marginally significant negative correlation with HRV in bereaved subjects.

CONCLUSION

The present data suggest that differences in HR and HRV could be associated with increased cardiovascular fatalities in bereaved individuals, known as the "broken heart phenomenon." These physiological differences have potential implications for both the mental and physical health of the bereaved.

Effects of Total Sleep Deprivation on Cardiovascular Parameters: An Absence of Biologically Significant Findings?

Abstract The present study analyzes the variations of heart rate (HR) and systolic and diastolic blood pressure (SBP and DBP) during 60 h of total sleep deprivation (TSD). All variables were evaluated every 2 h in a resting condition, during the performance of a vigilance task. Thirty healthy volunteers (15 men and 15 women) from 18 to 24 years old participated in the experiment. The analyses of variance (ANOVAS) with repeated measures showed some modifications of HR and SBP mean values mainly marked by circadian oscillations. The circadian oscillations had a smaller amplitude for SBP than for HR. HR showed a slight decrease on the second night of TSD and a slight increase on the third day of TSD. SBP decreased during the first 24 h of TSD and after that maintained its values without significant changes. DBP did not show any significant variations during TSD. In addition, there were no differences in function of gender for the TSD effect on the studied variables. All these statistically significant findings, however, seem to have no biological or clinical relevance. These aspects as well as the possible relationships between our results and activation or stress levels during TSD are discussed.