Is the association between depression and blunted cardiovascular stress reactions mediated by perceptions of stress?

Emotion regulation tendencies and cardiovascular responses to repeated acute psychological stress

Poor emotion regulation has been associated with cardiovascular disease (CVD) through maladaptive cardiovascular responses to psychological stress. However, there has been scant research examining the relationship between emotion regulation and habituation of cardiovascular responses to recurrent stress, which may be more directly applicable to the experience of stress in everyday life. The aims of the current study were to examine the associations between emotion regulation tendencies and cardiovascular stress reactivity, as well as habituation of cardiovascular reactivity across repeated stressors. A sample of 453 participants (mean (SD) age = 19.5 (1.3) years; 62 % women) completed a repeated stress paradigm, which consisted of two 10-minute baselines and two identical 4-minute stress tasks, separated by a 10-minute recovery period. Heart rate (HR) was measured continuously; systolic/diastolic blood pressures (SBP/DBP) were measured every 2 min. At the end of the visit, participants completed the Emotion Regulation Questionnaire (ERQ) and Difficulties in Emotion Regulation Scale (DERS). Results indicate that impulse control difficulties when distressed (a DERS subscale) were significantly associated with blunted SBP, DBP, and HR reactivity to both stressors, as well as impaired HR habituation across the stressors. None of the ERQ subscales (cognitive reappraisal, expressive suppression) were found to be associated with cardiovascular stress reactivity or habituation. The outcomes of this study demonstrate a potential underlying physiological pathway through which impulse control difficulties when distressed may contribute to CVD risk. This study also reveals the importance of extending traditional cardiovascular stress reactivity protocols to include multiple exposures of the same stress task.

Type D personality is associated with lower cardiovascular reactivity to stress in women

OBJECTIVE

This study examines if Type D personality is (1) associated with cardiovascular reactivity to acute stress in a healthy sample, and (2) has predictive utility for cardiovascular reactivity above its individual subcomponents (negative affect; NA, social inhibition; SI), as well as anxiety and depression.

DESIGN

Undergraduate students (n = 173) competed a standardised cardiovascular reactivity experimental protocol consisting of resting baseline and stressor phase (mental arithmetic), with systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) monitored throughout.

MAIN OUTCOME MEASURES

The main outcome measures were cardiovascular reactivity to the stressor, which was operationalised as the difference between resting baseline and the stressor phase for SBP, DBP and HR.

RESULTS

The continuous Type D interaction term (NA × SI) significantly predicted lower SBP reactivity to the mental arithmetic stressor amongst women, independent of NA, SI and confounding variables. Moreover, this remained significant after adjustment for anxiety and depressive symptoms. Depression, NA and SI were also significant independent predictors of SBP reactivity amongst women.

CONCLUSION

Type D personality is associated with lower SBP reactivity to acute stress in women, which may be indicative of blunted cardiovascular reactivity. This association was independent of NA, SI, Anxiety and Depression.

Behavioural clusters characteristic of cardiovascular reactivity profiles relate to poorer health outcomes

OBJECTIVES

Blunted cardiovascular reactivity is associated with a distinct behavioural profile of greater exposure to early life adversity, coupled with higher levels of behavioural disengagement and symptoms of depression. The present study sought to extend on this work by investigating if behavioural clusters with distinct patterns of reactivity were related to health and behavioural outcomes at baseline and at a 4-year follow-up.

METHODS

Hierarchical cluster analyses were conducted using longitudinal data drawn from the Midlife Development in the United States (MIDUS 2) Biomarker Project and the MIDUS 3 follow-up 4 years later. During MIDUS, 2 participants (N = 513) underwent a standardized stress testing protocol and had their blood pressure and heart rate monitored throughout. In addition, hierarchical cluster analyses were conducted on responses from measures of early life adversity, behavioural disengagement and depression. Binary logistic regressions were conducted to determine whether cluster membership was related to health and behavioural outcomes which were taken at both time points.

RESULTS

Three behavioural clusters emerged with statistically different blood pressure reactivity patterns. The cluster characterized by greater exposure to early life adversity, higher levels of behavioural disengagement and depressive symptoms, had relatively lower blood pressure reactivity patterns compared with both the exaggerated reactivity cluster and the cluster similar to the sample mean. In fully adjusted models, this cluster was associated with hypertension (p = .050) and depressed affect (p = .033), while Cluster 1 characteristic of an exaggerated blood pressure reactivity profile was associated with depressed affect (p < .001). Cluster membership did not significantly predict future health status.

CONCLUSION

This study extends research on behavioural clusters characteristic of reactivity profiles to demonstrate how they relate to health and behavioural outcomes during MIDUS 2.

Lifetime Stressor Exposure and Psychophysiological Reactivity and Habituation to Repeated Acute Social Stressors

This study addressed whether lifetime stressor exposure was associated with psychophysiological reactivity and habituation to a novel laboratory-based stressor. Eighty-six participants (Mage = 23.31 years, SD = 4.94) reported their exposure to lifetime non-sport and sport-specific stressors before completing two consecutive trials of the Trier Social Stress Test, while cardiovascular (i.e., heart rate) and endocrine (i.e., salivary cortisol) data were recorded. Exposure to a moderate number of lifetime non-sport and sport-specific stressors was associated with adaptive cardiovascular reactivity, whereas very low or very high stressor exposure was related to maladaptive reactivity. Moreover, experiencing a very low number of lifetime non-sport (but not sport-specific) stressors was associated with poorer habituation. In contrast, lifetime stressor severity was unrelated to cardiovascular reactivity. Finally, greater lifetime non-sport and sport-specific stressor counts were associated with blunted cortisol reactivity and poorer habituation. These results suggest that lifetime stressor exposure may influence sport performers' acute stress responses.

Cluster analysis reveals distinct patterns of childhood adversity, behavioral disengagement, and depression that predict blunted heart rate reactivity to acute psychological stress

BACKGROUND

There is considerable evidence documenting associations between early life adversity, behavioral disengagement, and depression with blunted cardiovascular reactivity to acute psychological stress. However, while often examined as independent predictors, it is also likely that a combination of these factors uniquely relate to cardiovascular reactivity.

PURPOSE

The present study employed multivariate cluster analysis to examine if distinct combinations of these outcomes relate to cardiovascular stress reactivity.

METHODS

Participants (N = 467) were predominantly female (60.6%) with a mean age of 19.30 years (SD = 0.82). Measures of early life adversity, behavioral disengagement, and depression were completed; in addition, participants had their blood pressure and heart rate monitored throughout a standardized stress testing session. Cardiovascular reactivity was calculated as the difference between mean stress and mean baseline cardiovascular values.

RESULTS

Analyses revealed two clusters with distinct patterns of exposure to early life adversity, levels of behavioral disengagement and depression, uniquely related to cardiovascular reactivity. In unadjusted models, Cluster 1 that was characterized by greater exposure to early life adversity, higher levels of behavioral disengagement and depression, was associated with lower systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) reactivity. Cluster 2 was characterized by reactivity values similar to the sample means. In fully adjusted models, Cluster 1 predicted heart rate reactivity to stress.

CONCLUSIONS

The present study identifies a behavioral cluster that is characteristic of a blunted heart rate reactivity profile, significantly extending the research in this area.

Childhood Trauma and Cortisol Reactivity: An Investigation of the Role of Task Appraisals

Background

Childhood adversity is linked to adverse health in adulthood. One posited mechanistic pathway is through physiological responses to acute stress. Childhood adversity has been previously related to both exaggerated and blunted physiological responses to acute stress, however, less is known about the psychological mechanisms which may contribute to patterns of physiological reactivity linked to childhood adversity.

Objective

In the current work, we investigated the role of challenge and threat stress appraisals in explaining relationships between childhood adversity and cortisol reactivity in response to an acute stressor.

Methods

Undergraduate students (n = 81; 61% female) completed an online survey that included general demographic information and the Risky Families Questionnaire 24 h before a scheduled lab visit. In the lab, a research assistant collected a baseline salivary cortisol sample. Following the baseline period, participants were read instructions for the Trier Social Stress Test (TSST), a validated psychological lab stressor. Next, they completed a challenge vs. threat task appraisal questionnaire and completed the speech and math portion of the TSST. Twenty minutes following the start of the TSST, a second salivary sample was collected to measure changes in salivary cortisol following the TSST.

Results

Linear regression analyses adjusted for age, sex, childhood socioeconomic status (SES), and baseline cortisol levels, showed childhood adversity associated with changes in cortisol levels [B = –0.29 t(73) = –2.35, p = 0.02, R^2=0.07]. Linear regression analyses controlling for age, sex, and childhood SES showed childhood adversity associated with both challenge [B = –0.52 t(74) = –5.04, p < 0.001, R^2=0.24] and threat [B = 0.55 t(74) = 5.40, p < 0.001, R^2=0.27] appraisals. Significant indirect effects of childhood trauma on cortisol reactivity were observed through challenge appraisals [B = –0.01 (95% confidence interval = –0.02, –0.003)], and threat appraisals [B = –0.01 (95% confidence interval = –0.01, –0.003)].

Conclusion

Childhood adversity may contribute to blunted cortisol reactivity, a pattern of response which is linked to obesity, addiction, and other behavior-related diseases. Our findings suggest that this relationship is in part a product of stress appraisals.

Cardiovascular reactions to acute psychological stress and academic achievement

Cardiovascular reactions to acute psychological stress have been associated with cognitive function. However, previous work has assessed cardiovascular reactions and cognitive function in the laboratory at the same time. The present study examined the association between cardiovascular reactions to acute psychological stress in the laboratory and academic performance in final year high school students. Heart rate, blood pressure, stroke volume, and cardiac output reactions to an acute psychological stress task were measured in 131 participants during their final year of high school. Performance on high school A‐levels were obtained the following year. Higher heart rate and cardiac output reactivity were associated with better A‐level performance. These associations were still statistically significant after adjusting for a wide range of potentially confounding variables. The present results are consistent with a body of literature suggesting that higher heart rate reactions to acute psychological stress are associated with better cognitive performance across a variety of domains.

The present study is the first to examine the associations between cardiovascular reactions to stress in the laboratory and academic achievement. Additionally, it is the first to examine a more comprehensive hemodynamic profile of cardiovascular reactivity (e.g., cardiac output) with cognitive function. The present results are consistent with a body of literature suggesting that higher heart rate reactions to acute psychological stress are associated with better cognitive performance across a variety of domains.

Early Life Adversity and Blunted Cardiovascular Reactivity to Acute Psychological Stress: The Role of Current Depressive Symptoms

OBJECTIVE

The pathways underlying the early life adversity and cardiovascular reactivity association remain unclear. The current study examined the role of current depressive symptoms on this relationship.

METHODS

Mediation analyses were conducted using data from 639 participants drawn from the Midlife Development in the United States 2 Biomarker Project. Responses were derived from the Childhood Trauma Questionnaire and Center for Epidemiologic Studies Depression Scale. Participants had their systolic and diastolic blood pressure (SBP, DBP) and heart rate monitored throughout a standardized stress testing protocol.

RESULTS

The association between early life adversity and reactivity was mediated by current depressive symptoms; all adversity factors were linked to higher levels of current depressive symptoms, which, in turn, were associated with lower cardiovascular reactivity. For emotional abuse, this was noted for SBP (β = -0.06 [95% confidence interval {CI}, -0.13 to -0.01]) and DBP (β = -0.04 [-0.07 to -0.01]), physical abuse (SBP: β = -0.05 [-0.11 to -0.01]; DBP: β = -0.03 [-0.06 to -0.01]), sexual abuse (SBP: β = -0.04 [-0.09 to -0.01]; DBP: β = -0.02 [-0.05 to -0.01]), emotional neglect (SBP: β = -0.04 [-0.09 to -0.01]; DBP: β = -0.02 [-0.05 to -0.01]), physical neglect (SBP: β = -0.09 [-0.17 to -0.02]; DBP: β = -0.05 [-0.09 to -0.02]), and total Childhood Trauma Questionnaire score (SBP: β = -0.02 [-0.03 to -0.00]; DBP: β = -0.01 [-0.02 to -0.00]).

CONCLUSIONS

The present findings extend research and demonstrate that depression is an underlying mechanism linking early life adversity and blunted cardiovascular reactivity.

Adverse childhood experiences (ACEs) relate to blunted cardiovascular and cortisol reactivity to acute laboratory stress: A systematic review and meta-analysis

Adverse childhood experiences (ACEs) are associated with poor future mental and physical health. Altered biological reactivity to mental stress may be a possible mechanism linking ACEs to poor health. However, it is not clear if ACEs relate to blunted or exaggerated stress reactivity. This meta-analysis aimed to determine whether exposure to ACEs is associated with cardiovascular and cortisol stress reactivity. A systematic review yielded 37 sources. Random-effects modelling tested the aggregate effects of 83 studies of the association between ACEs and stress reactivity. Exposure to ACEs was associated with relatively blunted cardiovascular and cortisol stress reactivity. Effect sizes did not vary as a function of sample sex or reactivity measure (e.g., heart rate, blood pressure, or cortisol). Meta-regression revealed preliminary evidence of greater blunting in samples of a younger age and samples reporting greater ACE exposure. Subgroup analyses for stress task, ACE measurement instrument, and sample race were not conducted because of a lack of between-study variability. Exposure to ACEs is associated with dysregulation of multiple components of the human stress response system.

Exhausted Heart Rate Responses to Repeated Psychological Stress in Women With Major Depressive Disorder

Past research links depression and blunted cardiac vagal reactivity to chronic stress. Yet, to our knowledge no experiment investigates heart rate (variability) responses to a repeated laboratory stressor in patients with depression. Repeated exposure may provide valuable information on stress reactivity in depression. Fifty-nine women (30 inpatients diagnosed with depression and 29 matched controls) underwent two consecutive runs of a mental arithmetic stress paradigm consisting of one baseline and two exposures to control, stress, and recovery phases of 5 min each, in a case-control design. Subjective stress and electrocardiography were recorded. Variance of heart rate (HR) and root mean square of successive RR interval differences (RMSSD) were analyzed using linear mixed models. Overall, physiological parameters (HR and RMSSD) and subjective stress showed a strong group effect (all p < 0.001). In both groups, subjective stress and HR increased in response to stress, but the subjective stress levels of patients with depression did not return to baseline levels after the first stressor and for the remainder of the experiment (all p < 0.004 compared to baseline). Patients' HR reactivity responded oppositely: while HR recovered after the first stress exposure, no reactivity was observed in response to the second exposure. These findings may suggest that the often-reported blunted HR/HRV response to stressors results from exhaustion rather than an incapacity to react to stress. The altered HR reactivity could indicate allostatic (over-) load in depression.

The cumulative effect of chronic stress and depressive symptoms affects heart rate in a working population

BACKGROUND

Chronic stress and depressive symptoms have both been linked to increased heart rate (HR) and reduced HR variability. However, up to date, it is not clear whether chronic stress, the mechanisms intrinsic to depression or a combination of both cause these alterations. Subclinical cases may help to answer these questions. In a healthy working population, we aimed to investigate whether the effect of chronic stress on HR circadian rhythm depends on the presence of depressive symptoms and whether chronic stress and depressive symptoms have differential effects on HR reactivity to an acute stressor.

METHODS

1,002 individuals of the SWEET study completed baseline questionnaires, including psychological information, and 5 days of electrocardiogram (ECG) measurements. Complete datasets were available for 516 individuals. In addition, a subset (n = 194) of these participants completed a stress task on a mobile device. Participants were grouped according to their scores for the Depression Anxiety Stress Scale (DASS) and Perceived Stress Scale (PSS). We explored the resulting groups for differences in HR circadian rhythm and stress reactivity using linear mixed effect models. Additionally, we explored the effect of stress and depressive symptoms on night-time HR variability [root mean square of successive differences (RMSSD)].

RESULTS

High and extreme stress alone did not alter HR circadian rhythm, apart from a limited increase in basal HR. Yet, if depressive symptoms were present, extreme chronic stress levels did lead to a blunted circadian rhythm and a lower basal HR. Furthermore, blunted stress reactivity was associated with depressive symptoms, but not chronic stress. Night-time RMSSD data was not influenced by chronic stress, depressive symptoms or their interaction.

CONCLUSION

The combination of stress and depressive symptoms, but not chronic stress by itself leads to a blunted HR circadian rhythm. Furthermore, blunted HR reactivity is associated with depressive symptoms and not chronic stress.

Effect of childhood maltreatment on cardiovascular response habitation to repeated psychosocial stress

Childhood maltreatment as an early-life stress leads to cardiovascular stress response dysregulation manifested by either exaggerated or blunted stress responses. However, little is known how childhood maltreatment affects cardiovascular response habituation to recurrent stress, which implicated in the long-term health effects of chronic stress. The scale of Childhood Trauma Questionnaire (CTQ) was administered to 192 healthy undergraduates who underwent continuous cardiovascular monitoring [heart rate (HR), blood pressure (BP), cardiac output (CO) and total peripheral resistance (TPR)] while facing two consecutive psychosocial stress exposures (public speaking tasks). Results showed that childhood maltreatment was negatively associated with HR and CO reactivity to the first stress exposure and HR reactivity to the second stress exposure. Even after controlling for depression symptoms, both high and low childhood maltreatment groups (upper and lower 27% of total CTQ scores) exhibited HR and CO response habituation to repeated stress exposures, but high childhood maltreatment group showed blunted HR and CO reactivity to the first stress exposure compared with low childhood maltreatment group. These findings suggest that the observed cardiovascular response habituation to repeated stress following initial blunted (i.e., inadequate) reactivity among individuals with high childhood maltreated experiences might be maladaptive, which would lead to cardiovascular disease risk.

A Pilot Study of Temporal Associations Between Psychological Stress and Cardiovascular Response

Psychological stress (PS) in daily life can trigger acute changes in cardiovascular function and may lead to increased risk of cardiovascular problems. Prior laboratory-based studies provide little evidence on temporal changes in the associations between PS and cardiovascular responses in natural settings. We hypothesized that daily PS would be associated with higher heart rate (HR) and lower heart rate variability (HRV). Using smartphones, ten participants (four females, 21.1±1.1 years) completed ecological momentary assessment (EMA) 6 times a day for two weeks regarding their current affective state. Participants rated levels of PS, as well as 3 high-arousal negative affect (HNA: Anxious, Annoyed, and Upset), and 3 low-arousal negative affect (LNA: Sluggish, Bored, and Sad) states. They also wore a chest-mounted heart-rate monitor and a wrist accelerometer to monitor cardiovascular response and physical activity, respectively. HR and HRV variables in the time intervals (5, 30, 60 min) before and after EMA were used as indicators of cardiovascular response. Multilevel modeling was used to examine the association between affect and HR/HRV, controlling for physical activity. Higher HR and lower HRV were related to subsequent greater feelings of stress at the 5 and 30-min time intervals. No significant associations were observed between cardiovascular parameters and subsequent affective states, suggesting that the acute exaggerated cardiovascular responses occurred due to PS. Higher LNA was related to antecedent/subsequent lower HR or higher HRV within 2 hours, while HNA was unrelated to HR or HRV for all time intervals, suggesting that both high/low arousal NA were not related to exaggerated cardiovascular response. Understanding psychological feelings of stress and LNA may be helpful in the management of daily cardiovascular health.

Cardiovascular Stress Reactivity and Health: Recent Questions and Future Directions

OBJECTIVE

High cardiovascular reactions to psychological stress are associated with the development of hypertension, systemic atherosclerosis, and cardiovascular disease. However, it has become apparent that low biological stress reactivity also may have serious consequences for health, although less is known about the mechanisms of this. The objectives of this narrative review and opinion article are to summarize and consider where we are now in terms of the usefulness of the reactivity hypothesis and reactivity research, given that both ends of the reactivity spectrum seem to be associated with poor health, and to address some of the key criticisms and future challenges for the research area.

METHODS

This review is authored by the members of a panel discussion held at the American Psychosomatic Society meeting in 2019, which included questions such as the following: How do we measure high and low reactivity? Can high reactivity ever indicate better health? Does low or blunted reactivity simply reflect less effort on task challenges? Where does low reactivity originate from, and what is a low reactor?

RESULTS

Cardiovascular (and cortisol) stress reactivity are used as a model to demonstrate an increased understanding of the different individual pathways from stress responses to health/disease and show the challenges of how to understand and best use the reconstruction of the long-standing reactivity hypothesis given recent data.

CONCLUSIONS

This discussion elucidates the gaps in knowledge and key research issues that still remain to be addressed in this field, and that systematic reviews and meta-analyses continue to be required.

Eveningness, depression and cardiovascular reactivity to acute psychological stress: A mediation model

The psychological pathways linking depression to blunted cardiovascular reactivity (CVR) are still being elucidated. The purpose of the present study was to test whether the association between eveningness, a diurnal/sleep-wake preference and CVR would be mediated by depressive symptoms. One hundred and eighty-two healthy young adults completed measures of morningness/eveningness (the Morningness-Eveningness Questionnaire; MEQ-SA), depressive symptoms (Hospital Anxiety and Depression Scale; HADS) and had their blood pressure and heart rate monitored throughout a standardised stress testing protocol. Results indicated that depressive symptoms were negatively associated with systolic blood pressure (SBP) but not diastolic blood pressure (DBP) or heart rate (HR) reactions to the stress task. Eveningness was also negatively associated with both SBP and DBP, but not HR. As such, those who reported increased depressive symptomology, and higher scores on eveningness displayed a more blunted cardiovascular response. Furthermore, the latter relationship was mediated by depressive symptoms such that those reporting higher scores on eveningness also reported increased depressive symptomology and this resulted in blunted CVR for SBP. These findings withstood adjustment for several confounding factors including time of testing. In conclusion, the present findings highlight the importance of considering eveningness when looking at the depression-blunted CVR relationship.

Cardiovascular Variability and Reactivity in Major Depressive Disorder

Abstract. This study investigated cardiovascular variability and stress reactivity in major depressive disorder (MDD). While previous research has documented reduced heart rate variability, knowledge about blood pressure variability in MDD remains scarce. Regarding reactivity, a particular focus was placed on the time courses of the cardiovascular responses, which may provide insight into the autonomic mechanisms underlying the hypo-reactivity expected in MDD. In 76 MDD patients and 71 healthy controls, blood pressure was continuously recorded at rest and during mental stress induced by a 3-min serial subtraction task. Compared to controls, patients exhibited lower systolic and diastolic blood pressure, heart rate variability, and systolic and diastolic blood pressure variability. Moreover, smaller stress-related changes in heart rate, systolic and diastolic blood pressure, and sensitivity of the cardiac baroreflex arose in patients. Cardiovascular parameters did not differ between patients using antidepressants and unmedicated patients. According to time-course analysis, reduced hemodynamic modulations in MDD mainly occurred after 50 s of the stress period. Low heart rate variability in MDD reflects deficient top-down integration of the brain mechanisms allowing flexible autonomic and behavioral control; diminished blood pressure variability is indicative of poor homeostatic capacity with respect to the regulation of blood pressure and organ perfusion. Moreover, blunted cardiovascular reactivity implies poor adjustment of energetic resources to internal and environmental demands and may be a correlate of deficient motivational dynamics characterizing MDD. While cardiovascular hypo-reactivity in MDD may be mediated by baroreflex and adrenergic mechanisms, the fast-acting parasympathetic system may play a subordinate role.

Motivational orientation mediates the association between depression and cardiovascular reactivity to acute psychological stress

Recent theoretical developments in cardiovascular reactivity research suggest the association between depression and blunted reactions to stress is linked to motivational factors. Thus, the present study aimed to test whether the association between depressive symptoms and cardiovascular reactivity to acute stress was mediated by motivation; be it intrinsic or extrinsic motivation. One hundred and eighty-two healthy young adults completed measures of motivation (Global Motivation Scale; GMS), and depression (Hospital Anxiety and Depression Scale; HADS) and had their blood pressure and heart rate monitored throughout a standardised stress testing protocol. Results indicated that depression was negatively associated with both systolic blood pressure (SBP) and heart rate (HR) reactions to the stress task (all ps < .05), such that those who reported higher depressive symptomology displayed a blunted response. Furthermore this relationship was mediated by intrinsic, but not extrinsic motivation; the blunted responses were less pronounced through intrinsic motivation. The present findings add extensively to existing research and confirm that motivation is an underlying mechanism linking depression and cardiovascular reactivity.

Type D personality and blunted cardiovascular stress reactivity: Role of task engagement

OBJECTIVE

The underlying mechanisms for linking Type D personality to cardiovascular stress reactivity remain unknown. The present study explored the possible mediating role of cognitive appraisals of stress and/or motivational levels involved in stress in the association between Type D personality and cardiovascular stress reactivity.

DESIGN

Cross-sectional.

METHODS

Chinese version of Type D Scale-14 was administered to 154 undergraduate students who underwent psychosocial stress during which the physiological data were continuously monitored, and cognitive appraisals indexed by a ratio of perceived stress demands to perceived personal resources and motivational levels engaged in stress indexed by self-reported stress task engagement were immediately assessed after the stress exposure.

RESULTS

Results indicated that Type D personality was related to blunted HR, SBP, and DBP reactivity to stress. Self-reported stress task engagement mediated the relation between Type D personality and blunted cardiovascular stress reactivity. The mediation effect of cognitive appraisals on this link was non-significant.

CONCLUSIONS

These findings suggest that motivational disengagement in the psychosocial stress task might be an important pathway linking Type D personality to blunted cardiovascular stress reactivity.

The Impact of Psychological Functioning on Cardiovascular Disease

PURPOSE OF REVIEW

We report on recent findings pertaining to the relationship of both negative and positive indicators of psychological functioning with cardiovascular disease (CVD) and briefly describe possible mechanistic pathways to account for these relationships.

RECENT FINDINGS

A body of observational literature suggests that (1) depression is predictive of CVD and is a consequence of CVD; (2) anxiety is related to CVD but the precise nature of this relationship remains unclear; and (3) negative affectivity and Type D personality are constructs that combine aspects of negative psychological functioning that have shown relationships with CVD and are worthy of future investigation. Positive psychological constructs of meaning/purpose and optimism predict better cardiovascular outcomes and other positive psychological constructs have received promising, but limited, attention in the literature. Key remaining questions concern the magnitude and directionality of possible causal relationships as well as the mechanisms accounting for them.

American Indian young adults display diminished cardiovascular and cortisol responses to acute psychological stress

American Indian adults are at an increased risk for cardiovascular disease compared with non-Hispanic white adults. Scant research exists examining the underlying physiological and psychological mechanisms associated with these risks. This study aimed to examine possible psychological and physiological stress-related mechanisms related to cardiovascular disease risk in healthy American Indian and non-Hispanic white adults. Forty American Indian (60% female, Mean age = 19.93, SD = 2.08 years) and 45 non-Hispanic white (70% female, Mean age = 20.18, SD = 2.22 years) participants attended an in-person laboratory session. Salivary cortisol and cardiovascular activity were measured before (baseline), during, and after exposure to a 10-minute mental arithmetic task. Compared to non-Hispanic white participants, American Indian had diminished salivary cortisol (p < .001), blood pressure (p's < .001), and heart rate (p = .041) responses to acute psychological stress. These effects could not be accounted for by differences in task performance or self-reported engagement. Previous research has shown that exaggerated responses to stress are associated with increased risk of cardiovascular disease. However, diminished responses to stress are associated with early childhood stress and future adverse behaviors (e.g., addiction, obesity). Diminished reactivity may influence behaviors that can impact future development of cardiovascular disease in American Indian populations.

Diminished cardiovascular stress reactivity is associated with lower levels of social participation

Diminished cardiac reactions to acute psychological stress are associated with adverse behavioral and health-relevant outcomes. It has been proposed that diminished cardiac reactivity may be a marker for deficits in motivational functioning both at the biological and behavioral levels. Social participation reflects the frequency with which individuals participate in social events and has motivational components. As such, it is a distinct construct from other constructs such as social integration, which measures the number of social roles an individual has. Additionally, lower levels of social participation and diminished reactivity have been associated with similar adverse health outcomes. Therefore, it is possible that diminished cardiac reactivity is associated with lower levels of social participation. We aimed to examine whether diminished cardiovascular reactivity in response to an acute lab stressor was associated with reported social participation. The analyses were conducted using publicly available data from the Pittsburgh Cold Study 3 (PCS3). The PCS3 was a prospective viral-challenge study, which included participants completing an in-lab social evaluative stressor (N = 202, Age = M = 29.71, SD = 10.66) and measuring cardiovascular responses at baseline and in response to the stressor. Separate regression analyses for each cardiovascular variable (SBP, DBP, MAP, and HR) demonstrated that lower cardiovascular reactivity was associated with less social participation. These associations were still evident following adjustment for respective baseline cardiovascular levels, age, sex, race, depressive symptomology, body mass index, socioeconomic status, smoking status, and levels of social integration (R2 changes: ≥ 0.017; ps ≤ 0.02) The findings provide initial evidence that blunted cardiac reactivity may be a precursor to low levels of social participation.

Glutamate Within the Marmoset Anterior Hippocampus Interacts with Area 25 to Regulate the Behavioral and Cardiovascular Correlates of High-Trait Anxiety

High-trait anxiety is a risk factor for the development of affective disorders and has been associated with decreased cardiovascular and behavioral responsivity to acute stressors in humans that may increase the risk of developing cardiovascular disease. Although human neuroimaging studies of high-trait anxiety reveals dysregulation in primate cingulate areas 25 and 32 and the anterior hippocampus (aHipp) and rodent studies reveal the importance of aHipp glutamatergic hypofunction, the causal involvement of aHipp glutamate and its interaction with these areas in the primate brain is unknown. Accordingly, we correlated marmoset trait anxiety scores to their postmortem aHipp glutamate levels and showed that low glutamate in the right aHipp is associated with high-trait anxiety in marmosets. Moreover, pharmacologically increasing aHipp glutamate reduced anxiety levels in highly anxious marmosets in two uncertainty-based tests of anxiety: exposure to a human intruder with uncertain intent and unpredictable loud noise. In the human intruder test, increasing aHipp glutamate decreased anxiety by increasing approach to the intruder. In the unpredictable threat test, animals showed blunted behavioral and cardiovascular responsivity after control infusions, which was normalized by increasing aHipp glutamate. However, this aHipp-mediated anxiolytic effect was blocked by simultaneous pharmacological inactivation of area 25, but not area 32, areas which when inactivated independently reduced and had no effect on anxiety, respectively. These findings provide causal evidence in male and female primates that aHipp glutamatergic hypofunction and its regulation by area 25 contribute to the behavioral and cardiovascular symptoms of endogenous high-trait anxiety.SIGNIFICANCE STATEMENT High-trait anxiety predisposes sufferers to the development of anxiety and depression. Although neuroimaging of these disorders and rodent modeling implicate dysregulation in hippocampal glutamate and the subgenual/perigenual cingulate cortices (areas 25/32), the causal involvement of these structures in endogenous high-trait anxiety and their interaction are unknown. Here, we demonstrate that increased trait anxiety in marmoset monkeys correlates with reduced hippocampal glutamate and that increasing hippocampal glutamate release in high-trait-anxious monkeys normalizes the aberrant behavioral and cardiovascular responsivity to potential threats. This normalization was blocked by simultaneous inactivation of area 25, but not area 32. These findings provide casual evidence in primates that hippocampal glutamatergic hypofunction regulates endogenous high-trait anxiety and the hippocampal-area 25 circuit is a potential therapeutic target.

Heart rate and high frequency heart rate variability during stress as biomarker for clinical depression. A systematic review

The interaction of physical and mental vulnerability and environmental constraints is thought to foster the development of psychiatric disorders such as major depressive disorder (MDD). A central factor in the development of psychopathology is mental stress. Despite some evidence for parasympathetic withdrawal and sympathetic overactivity in MDD, the psychophysiological response to stress in depression is not clear-cut. Given the growing interest in heart rate and heart rate variability as indicators for remote monitoring of patients, it is important to understand how patients with MDD react to stress in a laboratory-controlled environment. We conducted a systematic review of studies using electrocardiography to derive heart rate and heart rate variability during stress in patients with clinical depression. We focused on well-validated stress tasks- the mental arithmetic stress task, the Trier social stress task and public speaking task- to minimize confounding effects due to the nature of the stressor. The majority of studies found hypo-reactivity during stress as a hallmark of depression as evidenced by lower fluctuation in heart rate and heart rate variability in the high-frequency band. We address the potential underlying biological mechanisms, the influence of covariates on these measures and briefly discuss the specificity and potential for remote monitoring by using these variables.

History of Preeclampsia Adds to the Deleterious Effect of Chronic Stress on the Cardiac Ability to Flexibly Adapt to Challenge

Preeclampsia, a pregnancy-specific disorder, presents a major health problem during gestation, but is also associated with increased risk for cardiovascular complications in later life. We aimed to investigate whether chronic stress experience and preeclampsia may have additive adverse effects on the cardiac ability to flexibly adapt to challenge, that is, to mount an appropriately vigorous heart rate response to an acute psychological challenge, or whether they may perhaps have synergistic effects (e.g., mutual augmentation of effects). Blunted cardiac responding to challenge has been linked to poor health outcomes in the longer term. Women previously affected by preeclampsia and women after uncomplicated pregnancies were tested 15-17 weeks post-partum in a standardized stress-reactivity protocol, while cardiovascular variables were simultaneously recorded. Changes in heart rate and blood pressure in response to the stressor were analyzed with regard to the effects of history of preeclampsia and chronic stress experience. Findings indicated blunted cardiac responses in women with higher chronic stress experience (p = 0.020) and, independently from that, in women with a history of preeclampsia (p = 0.018), pointing to an additive nature of the effects of preeclampsia and chronic stress on impaired cardiovascular functioning. Consequently, if both are present, a history of preeclampsia may add to the already deleterious effects of the experience of chronic stress. The additive nature of the effects suggests that stress-reducing interventions, albeit they will not eliminate the heightened cardiovascular risk in patients with a history of preeclampsia, may improve their overall prognosis by avoiding further accumulation of risk.

The behavioural, cognitive, and neural corollaries of blunted cardiovascular and cortisol reactions to acute psychological stress

Recent research shows that blunted cardiovascular and cortisol reactions to acute psychological stress are associated with adverse behavioural and health outcomes: depression, obesity, bulimia, and addictions. These outcomes may reflect suboptimal functioning of the brain's fronto-limbic systems that are needed to regulate motivated behaviour in the face of challenge. In support of this, brain imaging data demonstrate fronto-limbic hypoactivation during acute stress exposure. Those demonstrating blunted reactions also show impairments of motivation, including lower cognitive ability, more rapid cognitive decline, and poorer performance on motivation-dependent tests of lung function. Persons exhibiting blunted stress reactivity display well established temperament characteristics, including neuroticism and impulsivity, characteristic of various behavioural disorders. Notably, the outcomes related to blunted stress reactivity are similar to those that define Reward Deficiency Syndrome. Accordingly, some individuals may be characterised by a broad failure in cardiovascular and cortisol responding to both stress and reward, reflecting fronto-limbic dysregulation. Finally, we proffer a model of blunted stress reactivity, its antecedents and sequelae, and identify future research priorities.

Suicide ideation among high-risk adolescent females: Examining the interplay between parasympathetic regulation and friendship support

Poor physiological self-regulation has been proposed as a potential biological vulnerability for adolescent suicidality. This study tested this hypothesis by examining the effect of parasympathetic stress responses on future suicide ideation. In addition, drawing from multilevel developmental psychopathology theories, the interplay between parasympathetic regulation and friendship support, conceptualized as an external source of regulation, was examined. At baseline, 132 adolescent females (M age = 14.59, SD = 1.39) with a history of mental health concerns participated in an in vivo interpersonal stressor (a laboratory speech task) and completed self-report measures of depressive symptoms and perceived support within a close same-age female friendship. Respiratory sinus arrhythmia (RSA) was measured before and during the speech task. Suicide ideation was assessed at baseline and at 3, 6, and 9 months follow-up. The results revealed that females with greater relative RSA decreases to the laboratory stressor were at higher risk for reporting suicide ideation over the subsequent 9 months. Moreover, parasympathetic responses moderated the effect of friendship support on suicide ideation; among females with mild changes or higher relative increases in RSA, but not more pronounced RSA decreases, friendship support reduced risk for future suicide ideation. Findings highlight the crucial role of physiological and external regulation sources as protective factors for youth suicidality.

Differential Autonomic Nervous System Reactivity in Depression and Anxiety During Stress Depending on Type of Stressor

OBJECTIVES

It remains unclear whether depressive and anxiety disorders are associated with hyporeactivity or hyperreactivity of the autonomic nervous system (ANS) and whether deviant reactivity occurs in all types of stressors. This study compared ANS reactivity in people with current or remitted depression/anxiety with reactivity in healthy controls during two stress conditions.

METHODS

From the Netherlands Study of Depression and Anxiety, data of 804 individuals with current depression/anxiety, 913 individuals with remitted depression/anxiety, and 466 healthy controls (mean age = 44.1 years; 66.4% female) were available. Two conditions were used to evoke stress: a) an n-back task, a cognitively challenging stressor, and 2) a psychiatric interview, evoking personal-emotional stress related to the occurrence of symptoms of depression/anxiety. Indicators of ANS activity were heart rate (HR), root mean square of differences between successive interbeat intervals (RMSSD), respiratory sinus arrhythmia (RSA), and preejection period.

RESULTS

As compared with controls, participants with psychopathology had significant hyporeactivity of HR (controls = 4.1 ± 4.2 beats/min; remitted = 3.5 ± 3.5 beats/min; current psychopathology = 3.1 ± 3.4 beats/min), RMSSD (controls = -6.2 ± 14.5 milliseconds; remitted = -5.4 ± 17.8 milliseconds; current psychopathology = -3.5 ± 15.4 milliseconds), and RSA (controls = -9.3 ± 17.0 milliseconds; remitted = -7.4 ± 16.5 milliseconds; current psychopathology = -6.9 ± 15.0 milliseconds) during the n-back task. In contrast, during the psychiatric interview, they showed significant hyperreactivity of HR (controls = 2.7 ± 3.4 beats/min; remitted = 3.5 ± 3.4 beats/min; current psychopathology = 4.0 ± 3.3 beats/min), RMSSD (controls = -3.4 ± 12.2 milliseconds; remitted = -4.1 ± 12.1 milliseconds; current psychopathology = -5.6 ± 11.8 milliseconds), and RSA (controls = -3.8 ± 8.1 milliseconds; remitted = -4.3 ± 7.9 milliseconds; current psychopathology = -5.0 ± 7.9 milliseconds). The lack of group differences in preejection period reactivity suggests that the found effects were driven by altered cardiac vagal reactivity in depression/anxiety.

CONCLUSIONS

The direction of altered ANS reactivity in depressed/anxious patients is dependent on the type of stressor, and only the more ecologically valid stressors may evoke hyperreactivity in these patients.

How are neuroticism and depression related to the psychophysiological stress response to acute stress in healthy older people?

Neuroticism and depressive symptomatology have been related to a heightened and diminished physiological stress response, which may partly explain their negative relationship with health and wellbeing. Identifying factors that may increase disease vulnerability is especially relevant in older people, whose physiological systems decline. With this in mind, we investigated the influence of neuroticism and depression on the psychophysiological stress response in healthy older people (from 55 to 76years old). A total of 36 volunteers were exposed to a stressful task (Trier Social Stress Test, TSST), while 35 volunteers performed a control non-stressful task. The physiological stress response was assessed through measures of cortisol, alpha-amylase, heart rate (HR). Our results showed that, neuroticism was not related to physiological stress response. However, depression was related to higher cortisol response and lower HR reactivity in the stress condition. In summary, emotional states such as depressive mood seem to amplify the cortisol stress response and reduce the cardiovascular response, whereas more stable dispositions such as neuroticism did not affect stress response in older people. These findings confirm, in healthy older people, the adverse effects of depression, acting on different subsystems of the stress response.

Problematic Internet use, excessive alcohol consumption, their comorbidity and cardiovascular and cortisol reactions to acute psychological stress in a student population

BACKGROUND AND AIMS

Problematic Internet use and excessive alcohol consumption have been associated with a host of maladaptive outcomes. Further, low (blunted) cardiovascular and stress hormone (e.g. cortisol) reactions to acute psychological stress are a feature of individuals with a range of adverse health and behavioural characteristics, including dependencies such as tobacco and alcohol addiction. The present study extended this research by examining whether behavioural dependencies, namely problematic Internet use, excessive alcohol consumption, and their comorbidity would also be associated with blunted stress reactivity.

METHODS

A large sample of university students (N = 2313) were screened using Internet and alcohol dependency questionnaires to select four groups for laboratory testing: comorbid Internet and alcohol dependence (N = 17), Internet dependence (N = 17), alcohol dependence (N = 28), and non-dependent controls (N = 26). Cardiovascular activity and salivary cortisol were measured at rest and in response to a psychological stress protocol comprising of mental arithmetic and public speaking tasks.

RESULTS

Neither problematic Internet behaviour nor excessive alcohol consumption, either individually or in combination, were associated with blunted cardiovascular or cortisol stress reactions. Discussion It is possible that problematic Internet behaviour and excessive alcohol consumption in a student population were not related to physiological reactivity as they may not reflect ingrained addictions but rather an impulse control disorder and binging tendency.

CONCLUSIONS

The present results serve to indicate some of the limits of the developing hypothesis that blunted stress reactivity is a peripheral marker of the central motivational dysregulation in the brain underpinning a wide range of health and behavioural problems.

Emotional non-acceptance links early life stress and blunted cortisol reactivity to social threat

Early life stress (ELS) has been recently associated with blunted cortisol reactivity and emotion dysregulation, but no study until now examined whether these characteristics are related. The main goal of this study was to examine the potential mediator role of emotion dysregulation in the relation between ELS and cortisol reactivity to social threat. Only women who were free of psychiatric and endocrine disorders, had regular menstrual cycle and did not use oral contraceptives were selected for this study (N=62). After filling in ELS and multidimensional emotion dysregulation measures, participants underwent the Trier Social Stress Test during which cortisol and autonomic responses were assessed. Most participants (85.5%) reported one or more major stressful events (i.e., physical abuse, sexual abuse, major parental conflicts, death of a family or close friend, severe illness) experienced before age 17. ELS was negatively associated with cortisol reactivity and positively associated with skin conductance level (SCL) reactivity, but it did not influence heart rate and respiratory sinus arrhythmia. In addition, ELS was positively related to emotional non-acceptance (i.e., a tendency to develop secondary emotional responses to one's negative emotions), and the latter was negatively related to cortisol responses and positively related to SCL responses. Bootstrapping analyses indicated that emotional non-acceptance was a significant mediator in the relationships between ELS and both cortisol and SCL responses. Emotional non-acceptance is thus one of the psychological mechanisms underlying blunted cortisol and increased sympathetic reactivity in young healthy volunteers with a history of ELS.

Blunted exercise-induced mobilization of monocytes in somatization syndromes and major depression

BACKGROUND

Previous research indicates that physical activity may alter the number of immune cells. We examined whether increasing or decreasing the level of physical activity affects circulating lymphocyte and monocyte counts in patients with somatization syndromes and patients with major depression.

METHODS

Thirty-eight participants with major depression, 26 participants with somatization syndromes and 47 healthy controls participated in the study. Using an experimental within-subject design, participants were involved in 1 week of increased physical activity (daily exercise sessions) and 1 week of reduced physical activity. Counts of total lymphocytes, lymphocyte subsets and monocytes were determined before and after each trial. Linear mixed models adjusted for sex, body mass index, age, fitness status and the order of trials were used for longitudinal data analysis.

RESULTS

One week of exercise increases the number of monocytes in healthy controls (p<.05), but not in patients with somatization syndromes or patients with major depression. In addition, after 1 week of exercise, depressive symptoms were reduced in patients with major depression (p<.05) while somatoform symptoms were reduced (p<.05) in both clinical groups. Baseline comparisons and mixed models indicated reduced T helper cell counts in patients with somatization syndromes.

LIMITATIONS

Relatively small sample size. The time of physical activity was relatively short and restricted to low-graded exercise.

CONCLUSIONS

This study demonstrates a blunted mobilization of monocytes by exercise in both patients with somatization syndromes and patients with major depression. In addition, even one week of exercise reduces somatoform and depressive symptoms.

Does stress elicit depression? Evidence from clinical and preclinical studies

Exposure to stressful situations may induce or deteriorate an already existing depression. Stress-related depression can be elicited at an adolescent/adult age but evidence also shows that early adverse experiences even at the fetal stage may predispose the offspring for later development of depression. The hypothalamus-pituitary-adrenal axis (HPA-axis) plays a key role in regulating the stress response and dysregulation in the system has been linked to depression both in humans and in animal models. This chapter critically reviews clinical and preclinical findings that may explain how stress can cause depression, including HPA-axis changes and alterations beyond the HPA-axis. As stress does not elicit depression in the majority of the population, this motivated research to focus on understanding the biology underlying resilient versus sensitive subjects. Animal models of depression have contributed to a deeper understanding of these mechanisms. Findings from these models will be presented.

Integrative commentary: implications of blunted reactivity

The previous issue of the International Journal of Psychophysiology was a special issue that collected some of the latest emerging evidence on blunted reactivity and its relationships with a variety of negative health outcomes. This commentary on the special issue briefly reviews each of the contributions and then provides some thoughts on the general themes that run through these papers. The findings from the special issue suggest that both lower and higher than expected cardiovascular and neuroendocrine responses to active psychological challenges may be maladaptive and differentially associated with adverse health sequelae.