Attenuated Heart Rate Responses to Public Speaking in Individuals With Alcohol Dependence

Immersive virtual plus-maze to examine behavior and psychophysiological-related variables in young people with problematic alcohol and cannabis consumption

Stressful events appear to be risky situations that can precipitate the consumption of drugs. One way to recreate stressful contexts, in an ecological and controlled method, is through immersive virtual reality (VR). In our study, we designed the scenario of an elevated plus-maze (EPM) using VR, which is widely used in animal models to assess unconditioned anxiety. This task allowed us to analyze the behavioral, psychophysiological (heart rate and electrodermal activity), and hormonal response (salivary cortisol and Alpha-amylase) to this stressful situation in different moments (before VR task (anticipation), at the end of the task and 10 minutes later) in young people with problematic alcohol use (AU, n = 27), alcohol combined with cannabis consumption (AU + C, n = 10), as well as in a control group (CO, n = 33). Behavioral analysis revealed that the AU group displayed fewer entries into open arms than the CO group, whereas both experimental groups spent less time at the end of the open arms, as well as lower time by look down index compared to the CO group. Moreover, our VR EPM induced different psychophysiological responses in the different moments measured. In general, electrodermal activity seemed to be a good biomarker of recovery from a stressful situation, as once the exposure to the stressful situation ended, the AU + C group took longer to recover compared to the CO group. Regarding hormonal analyses, we observed a similar response pattern in all groups suggesting that our VR task was able to activate both stress systems. The alpha-amylase to cortisol ratio, proposed as a biomarker of stress systems dysregulation, was higher in the group of young participants with alcohol abuse. Interestingly, our VR EPM was able to induce a slight alcohol craving in both experimental groups. In conclusion, our results suggest certain subtle behavioral and physiological differences that could be used to detect young individuals at risk of future severe addictions or other stress-related comorbidities. Moreover, it could help us to develop prevention strategies focused on emotional, cognitive, and psychophysiological aspects.

Blunted cortisol and normal sympathetic nervous system responses to an acute psychosocial stressor in internet addiction

Studies have demonstrated that addiction leads to blunted responses of cortisol and sympathetic nervous system (SNS) to acute stressors; however, limited studies have examined the neuroendocrine and SNS stress responses in Internet addiction (IA). To examine acute stress responses in IA, the current study recruited a total of 76 Japanese university students and staff members (51 females and 25 males, mean age = 22.4 years, SD = 4.7), and measured the salivary cortisol, salivary alpha-amylase (sAA), and blood pressure (BP) responses to an acute stressor under stress or a nonstress placebo conditions in IA and non-IA groups. The results revealed that patients with IA showed a blunted cortisol response to a stressor. In contrast, no differences were found in the sAA and BP responses between the IA and non-IA groups. These results suggest that IA may be characterized by blunted cortisol responses in acute stress settings.

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.

The physiological responses to acute stress in alcohol-dependent patients: A systematic review

Dysregulation of physiological stress reactivity plays a key role in the development and relapse risk of alcohol dependence. This article reviews studies investigating physiological responses to experimentally induced acute stress in patients with alcohol dependence. A systematic search from electronic databases resulted in 3641 articles found and after screening 62 articles were included in our review. Studies are analyzed based on stress types (i.e., social stress tasks and nonsocial stress tasks) and physiological markers (i.e., the nervous system, the endocrine system, somatic responses and the immune system). In studies applying nonsocial stress tasks, alcohol-dependent patients were reported to show a blunted stress response compared with healthy controls in the majority of studies applying markers of adrenocorticotropic hormone and cortisol. In studies applying social stress tasks, findings are inconsistent, with less than half of the studies reporting altered physiological stress responses in patients. We discuss the impact of duration of abstinence, comorbidities, baseline physiological arousal and intervention on the discrepancy of study findings. Furthermore, we review evidence for an association between blunted physiological stress responses and the relapse risk among patients with alcohol dependence.

Blunted cardiovascular reactivity to acute psychological stress predicts low behavioral but not self-reported perseverance: A replication study

Emerging evidence suggests that individuals with poor behavioral perseverance show low or blunted physiological responses to acute psychological stress. For example, a recent preliminary laboratory study demonstrated that blunted responders give up sooner and take fewer attempts when endeavoring to complete an impossible puzzle, but do not self-report poor perseverance. This present research is a replication of the previous study with an increased sample size, longer recovery periods between tasks and addition of social evaluation to the cold pressor. Participants (147) completed a self-report perseverance questionnaire (Short Grit Scale) and behavioral perseverance tasks (impossible Euler puzzle and socially evaluated cold-pressor (SECPT)). The number of attempts and time spent trying to complete the unsolvable puzzle, and duration of hand submergent during the SECPT, were recorded as behavioral perseverance measures. Difference in blood pressure (BP) and pulse rate (PR) from baseline to a 10-min paced auditory serial addition task (PASAT) were computed as reactivity. As previously, reactivity did not relate to self-reported perseverance and blunted BP reactivity to the PASAT was associated with less time persevering at the unsolvable puzzle. Additionally, blunted BP and PR reactivity to the PASAT related to poorer perseverance during the SECPT. These findings, replicating the previous study, increase confidence that blunted reactivity is a physiological marker of poor behavioral perseverance. Moreover, given that self-reported perseverance does not relate to reactivity, this suggests that blunted responders are not conscious of this detriment in perseverance, but likely need additional support when persistence is critical (e.g., during behavior change).

What is the role of stress cardiovascular reactivity in health behaviour change? A systematic review, meta-analysis and research agenda

OBJECTIVE

The stress reactivity hypothesis posits that the extremes of exaggerated and low or blunted cardiovascular reactivity (CVR) to stress may lead to adverse health outcomes via psychophysiological pathways. A potential indirect pathway between CVR and disease outcomes is through health-related behaviour and behaviour change. However, this is a less well understood pathway. Design: A registered systematic review was undertaken to determine the association between cardiovascular reactivity (CVR) and health behaviour change, as well as identify mediators and moderators. Eight papers that met the inclusion criteria, focused on smoking cessation and weight loss, were identified. Results: Pooling data from studies exploring the prospective relationship between CVR (as systolic blood pressure) and smoking cessation found that exaggerated CVR was associated with smoking relapse (Hedges' g = 0.39, SE = 0.00, 95% CI 0.38 - 0.40, p < .001; I2 = 0%; N = 257) but did not find evidence that CVR responses were associated with changes in weight. In order to advance our understanding of reactivity as a modifiable determinant of health behaviour change, our review recommends exploring the association between CVR and other health behaviours, to determine the influence of blunted reactivity versus low motivational effort identify mediators and moderators and determine the focus of interventions.

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.

Cognitive Bias of Interpretation in Type D Personality: Associations with Physiological Indices of Arousal

It is argued that the Type D person experiences increased distress when encountering social situations, which results in altered stress responding. However, little is known about how Type D individuals behave or feel during social interactions. Using a within-subjects design, the present study examined the physiological arousal of Type D and non-Type D individuals when rating how they would deal with a number of hypothetical social situations. Results showed that across all social situations, Type D individuals experienced greater levels of discomfort. In clearly negative and ambiguously neutral situations, this was paired with higher pulse rate. This study shows that the Type D individual not only reports greater discomfort but also experiences changes physiologically that support the role of the cardiovascular system as a potential psychosomatic pathway to disease.

Blood pressure reactivity to psychological stress is associated with clinical outcomes in patients with heart failure

INTRODUCTION

Cardiovascular (CV) reactivity to psychological stress has been implicated in the development and exacerbation of cardiovascular disease (CVD). Although high CV reactivity traditionally is thought to convey greater risk of CVD, the relationship between reactivity and clinical outcomes is inconsistent and may depend on the patient population under investigation. The present study examined CV reactivity in patients with heart failure (HF) and its potential association with long-term clinical outcomes.

METHODS

One hundred ninety-nine outpatients diagnosed with HF, with ejection fraction ≤40%, underwent an evaluation of blood pressure (BP) and heart rate reactivity to a laboratory-based simulated public-speaking stressor. Cox proportional hazards regression models were used to examine the prospective association between BP and heart rate reactivity on a combined end point of death or CV hospitalization over a 5-year median follow-up period.

RESULTS

Both systolic blood pressure (SBP) and diastolic blood pressure (DBP) reactivity, quantified as continuous variables, were inversely related to risk of death or CV hospitalization (Ps < .01) after controlling for established risk factors, including HF disease severity and etiology. In similar models, heart rate reactivity was unrelated to outcome (P = .12). In models with tertiles of reactivity, high SBP reactivity, compared with intermediate SBP reactivity, was associated with lower risk (hazard ratio [HR] = .498, 95% CI .335-.742, P =.001), whereas low SBP reactivity did not differ from intermediate reactivity. For DBP, high reactivity was marginally associated with lower risk compared with intermediate DBP reactivity (HR = .767, 95% CI .515-1.14, P =.193), whereas low DBP reactivity was associated with greater risk (HR = 1.49, 95% CI 1.027-2.155, P =.0359). No relationship of heart rate reactivity to outcome was identified.

CONCLUSIONS

For HF patients with reduced ejection fraction, a robust increase in BP evoked by a laboratory-based psychological challenge was associated with lower risk for adverse CVD events and may be a novel and unique marker of left ventricular systolic reserve that is accompanied by a more favorable long-term prognosis.

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.

Early-Life Adversity Interacts with FKBP5 Genotypes: Altered Working Memory and Cardiac Stress Reactivity in the Oklahoma Family Health Patterns Project

Exposure to stress during critical periods of development can have adverse effects on adult health behaviors, and genetic vulnerabilities may enhance these stress effects. We carried out an exploratory examination of psychological, physiological, and behavioral characteristics of 252 healthy young adults for the impact of early-life adversity (ELA) in relation to the G-to-A single nucleotide polymorphism (SNP), rs9296158, of the FKBP5 gene. FKBP5 is a molecular cochaperone that contributes to the functional status of the glucocorticoid receptor (GR) and to the quality of corticosteroid signaling. FKBP5 expression is upregulated by cortisol exposure during stressful episodes, with greater upregulation seen in A-allele carriers. As such, FKBP5 expression and GR function may be environmentally sensitive in A-allele carriers and therefore suitable for the study of gene-by-environment (G × E) interactions. Compared with FKBP5, GG homozygotes (N=118), A-allele carriers (N = 132) without psychiatric morbidity had progressively worse performance on the Stroop color-word task with increasing levels of ELA exposure (Genotype × ELA, F=5.14, P=0.007), indicating a G × E interaction on working memory in early adulthood. In addition, heart rate response to mental stress was diminished overall in AA/AG-allele carriers (F=5.15, P=0.024). Diminished working memory and attenuated autonomic responses to stress are both associated with risk for alcoholism and other substance use disorders. The present data suggest that FKBP5 in the GR pathway may be a point of vulnerability to ELA, as seen in this group of non-traumatized young adults. FKBP5 is accordingly a potential target for more extensive studies of the impact of ELA on health and health behaviors in adulthood.

Blunted cardiac stress reactors exhibit relatively high levels of behavioural impulsivity

Blunted physiological reactions to acute psychological stress are associated with a range of adverse health and behavioural outcomes. This study examined whether extreme stress reactors differ in their behavioural impulsivity. Individuals showing blunted (N=23) and exaggerated (N=23) cardiovascular reactions to stress were selected by screening a healthy student population (N=276). Behavioural impulsivity was measured via inhibitory control and motor impulsivity tasks. Blunted reactors exhibited greater impulsivity than exaggerated reactors on both stop-signal, F(1,41)=4.99, p=0.03, ηp(2)=0.108, and circle drawing, F(1,43)=4.00, p=0.05, η p(2)=0.085, tasks. Individuals showing blunted cardiovascular stress reactions are characterized by greater impulsivity which may contribute to their increased susceptibility to outcomes such as obesity and addiction.

Risk factors for alcoholism in the Oklahoma Family Health Patterns project: impact of early life adversity and family history on affect regulation and personality

AIM

This study examined the impact of early lifetime adversity (ELA) on affect regulation and personality in persons with family history (FH+) and without (FH-) a family history of alcoholism. We examined the impact of early life adversity in healthy young adults, 18-30 years of age enrolled in a long-term study on risk for alcohol and other substance abuse.

METHODS

ELA was assessed by a composite score of low socioeconomic status and personal experience of physical or sexual abuse and/or separation from parents before age 16, resulting in a score of 0, 1-2, or >3 adverse events. Unstable affect regulation and personality variables were obtained via self-report measures.

RESULTS

Higher ELA scores were seen in FH+ (χ(2)=109.2, p<0.0001) and in women (χ(2)=17.82, p=0.0019). Although higher ELA predicted less emotional stability and more behavioral undercontrol, further analysis including both FH and ELA showed that FH+ persons are prone to poor affect regulation, negative moods, and have risky drinking and drug abuse tendencies independent of ELA level. ELA predicts reduced stress reactivity and poorer cognitive control over impulsive behaviors as shown elsewhere.

CONCLUSIONS

The present work shows that FH+ have poor mood regulation and antisocial characteristics. The greater prevalence of ELA in FH+ persons indicates that life experience and FH+ work in tandem to result in risky patterns of alcohol and drug experimentation to elevate risk for alcoholism. Further studies of genetic and environmental contributions to alcoholism are called for.

Blunted Heart Rate Response as a Potential Endophenotype of Substance Use Disorders: Evidence from High-Risk Youth

BACKGROUND

Children of parents with a substance use disorder (CPSUD) are at increased risk for developing problematic substance use later in life. Endophenotypes may help to clarify the mechanism behind this increased risk. However, substance use and externalizing symptoms may confound the relation between dysregulated physiological stress responding and familial risk for substance use disorders (SUDs).

METHODS

We examined whether heart rate (HR) responses differed between CPSUDs and controls. Participants (aged 11-20 years) were CPSUDs (N = 75) and controls (N = 363), semi-matched on the basis of sex, socioeconomic status, and ethnicity. HR was measured continuously during a psychosocial stress procedure. Substance use and externalizing symptoms were self-reported and mother-reported, respectively.

RESULTS

A piecewise, mixed-effects model was fit for HR across the stress procedure, with fixed effects for HR reactivity and HR recovery. CPSUDs showed a blunted HR recovery. CPSUDs reported drinking more frequently, were more likely to use tobacco daily, were more likely to report ever use of cannabis and used cannabis more frequently, and exhibited more externalizing symptoms. These variables did not confound the relation between familial risk for SUDs and a blunted HR recovery.

CONCLUSION

Our findings suggest dysregulated autonomic nervous system (ANS) responding in CPSUDs and contribute to the accumulating evidence for ANS dysregulation as a potential endophenotype for SUDs.

Neuroendocrine and cardiovascular reactions to acute psychological stress are attenuated in smokers

A number of studies have now examined the association between smoking and the magnitude of physiological reactions to acute psychological stress. However, no large-scale study has demonstrated this association incorporating neuroendocrine in addition to cardiovascular reactions to stress. The present study compared neuroendocrine and cardiovascular reactions to acute stress exposure in current smokers, ex-smokers, and those who had never smoked in a large community sample. Salivary cortisol, systolic and diastolic blood pressure, heart rate and frequency components of systolic blood pressure and heart rate variability were measured at rest and during exposure to a battery of three standardized stress tasks in 480 male and female participants from the Dutch Famine Birth Cohort Study. Current smokers had significantly lower cortisol, systolic and diastolic blood pressure, and heart rate reactions to stress. They also exhibited smaller changes in the low frequency band of blood pressure variability compared to ex- and never smokers. There were no group differences in stress related changes in overall heart rate variability as measured by the root mean square of successive interbeat interval differences or in the high frequency band of heart rate variability. In all cases, effects remained significant following statistical adjustment for a host of variables likely to be associated with reactivity and/or smoking. In secondary analyses, there were no significant associations between lifetime cigarette consumption or current consumption and stress reactivity. In conclusion, compared to non-smokers and ex-smokers, current smokers exhibited attenuated neuroendocrine and cardiovascular reactions to acute psychological stress. Among smokers and ex-smokers, there is no evidence that lifetime exposure was associated with physiological reactions to acute stress, nor that current levels of cigarette consumption were associated with reactivity. It is possible, then, that attenuated stress reactivity may be a marker for an increased susceptibility to take up and/or maintain smoking behaviour once initiated.

Experimental public speaking: contributions to the understanding of the serotonergic modulation of fear

Public speaking is widely used as a model of experimental fear and anxiety. This review aimed to evaluate the effects of pharmacological challenges on public speaking responses and their implications for the understanding of the neurobiology of normal and pathological anxiety, specifically panic disorder. We also describe methodological features of experimental paradigms using public speaking as an inducer of fear and stress. Public speaking is a potent stressor that can provoke significant subjective and physiological responses. However, variations in the manners in which public speaking is modelled can lead to different responses that need to be considered when interpreting the results. Results from pharmacological studies with healthy volunteers submitted to simulated public speaking tests have similarities with the pharmacological responses of panic patients observed in clinical practice and panic patients differ from controls in the response to the public speaking test. These data are compatible with the Deakin and Graeff hypothesis that serotonin inhibits fear, as accessed by public speaking tasks, and that this inhibition is likely related to the actions of serotonin in the dorsal periaqueductal grey matter.

Is blunted cardiovascular reactivity in depression mood-state dependent? A comparison of major depressive disorder remitted depression and healthy controls

Prior work has repeatedly demonstrated that people who have current major depression exhibit blunted cardiovascular reactivity to acute stressors (e.g., Salomon et al., 2009). A key question regards the psychobiological basis for these deficits, including whether such deficits are depressed mood-state dependent or whether these effects are trait-like and are observed outside of depression episodes in vulnerable individuals. To examine this issue, we assessed cardiovascular reactivity to a speech stressor task and a forehead cold pressor in 50 individuals with current major depressive disorder (MDD), 25 with remitted major depression (RMD), and 45 healthy controls. Heart rate (HR), blood pressure and impedance cardiography were assessed and analyses controlled for BMI and sex. Significant group effects were found for SBP, HR, and PEP for the speech preparation period and HR, CO, and PEP during the speech. For each of these parameters, only the MDD group exhibited attenuated reactivity as well as impaired SBP recovery. Reactivity and recovery in the RMD group more closely resembled the healthy controls. Speeches given by the MDD group were rated as less persuasive than the RMD or healthy controls' speeches. No significant differences were found for the cold pressor. Blunted cardiovascular reactivity and impaired recovery in current major depression may be mood-state dependent phenomena and may be more reflective of motivational deficits than deficits in the physiological integrity of the cardiovascular system.

Alcohol and tobacco use and heart rate reactivity to a psychosocial stressor in an adolescent population

BACKGROUND

Few studies have investigated physiological stress (re)activity in relation to substance use, especially in adolescents. Using substances is one way to stimulate physiological arousal, therefore inherent hypo-arousal may be associated with substance use in adolescents. The purpose of this study was to examine the relation of autonomic nervous system (ANS) activity with alcohol and tobacco use in adolescents.

METHODS

ANS activity and perceived stress during a social stress procedure were examined in relation to substance use. 275 Dutch adolescents from a general population study provided complete data. Heart rate was recorded continuously during a pre-task rest period, a stressful task period and a post-task recovery period. Alcohol and tobacco use were self-reported.

RESULTS

Adolescents who consumed a medium and high number of alcoholic drinks per week (more than two) exhibited lower heart rates during the entire stress procedure as compared to those who consumed a low number of alcoholic drinks. Adolescents who smoked every day portrayed blunted heart rate reactivity to stress as compared to adolescents who smoked less frequently or not at all. Perceived stress was not related to alcohol or tobacco use.

CONCLUSIONS

Overall lower heart rate in adolescents who drank more and blunted heart rate reactivity to stress in those who used tobacco every day may indicate inherent hypo-arousal of the ANS system in those vulnerable to use substances more often. These adolescents may actively seek out substances in order to achieve a more normalized state of arousal.

Early life adversity reduces stress reactivity and enhances impulsive behavior: implications for health behaviors

Altered reactivity to stress, either in the direction of exaggerated reactivity or diminished reactivity, may signal a dysregulation of systems intended to maintain homeostasis and a state of good health. Evidence has accumulated that diminished reactivity to psychosocial stress may signal poor health outcomes. One source of diminished cortisol and autonomic reactivity is the experience of adverse rearing during childhood and adolescence. The Oklahoma Family Health Patterns Project has examined a cohort of 426 healthy young adults with and without a family history of alcoholism. Regardless of family history, persons who had experienced high degrees of adversity prior to age 16 had a constellation of changes including reduced cortisol and heart rate reactivity, diminished cognitive capacity, and unstable regulation of affect, leading to behavioral impulsivity and antisocial tendencies. We present a model whereby this constellation of physiological, cognitive, and affective tendencies is consistent with altered central dopaminergic activity leading to changes in brain function that may foster impulsive and risky behaviors. These in turn may promote greater use of alcohol other drugs along with adopting poor health behaviors. This model provides a pathway from early life adversity to low stress reactivity that forms a basis for risky behaviors and poor health outcomes.

Cardiovascular and cortisol reactions to acute psychological stress and adiposity: cross-sectional and prospective associations in the Dutch Famine Birth Cohort Study

OBJECTIVE

In recent analyses of data from a large community sample, negative cross-sectional and prospective associations between cardiac stress reactivity and obesity were observed. The present study reexamined the association between cardiovascular reactivity and adiposity in the Dutch Famine Birth Cohort, with the additional aim of examining the association between cortisol reactivity and adiposity.

METHODS

Blood pressure, heart rate, and salivary cortisol were measured at rest and in response to standard laboratory stress tasks in 725 adults. Height, weight, waist-and-hip circumference, and skinfold thickness were measured. Between 4 to 7 years later, 460 participants reported current height and weight. Obesity was defined as a body mass index of 30 kg/m(2) or higher.

RESULTS

Those with a greater body mass index (β = -0.39 beats per minute (bpm)), waist-to-hip ratio (β = -0.15 bpm), and triceps and subscapular skinfold thicknesses (β = -1.0 and -1.8 bpm) or who were categorized as obese (-3.9 bpm) displayed smaller cardiac reactions to acute stress (all p < .001). With the exception of waist-to-hip ratio, the same negative associations emerged for cortisol reactivity (all p ≤ .01). In prospective analyses, low cardiac reactivity was associated with an increased likelihood of becoming or remaining obese in the subsequent 4 to 7 years (odds ratio = 1.03, p = .01). All associations withstood adjustment for a range of possible confounders.

CONCLUSIONS

The present analyses provide additional support for the hypothesis that it is low not high cardiac and cortisol stress reactivity that is related to adiposity.

Disordered eating behaviour is associated with blunted cortisol and cardiovascular reactions to acute psychological stress

Research suggests a potential dysregulation of the stress response in individuals with bulimia nervosa. This study measured both cardiovascular and cortisol reactions to a standardised laboratory stress task in individuals identified as showing disordered eating behaviour to determine whether dysregulation of the stress response is characteristic of the two branches of the stress response system. Female students (N=455) were screened using two validated eating disorder questionnaires. Twelve women with disordered eating, including self-induced vomiting, and 12 healthy controls were selected for laboratory stress testing. Salivary cortisol and cardiovascular activity, via Doppler imaging and semi-automatic blood pressure monitoring, were measured at resting baseline and during and after exposure to a 10-min mental arithmetic stress task. Compared to controls the disordered eating group showed blunted cortisol, cardiac output, heart rate, and stroke volume reactions to the acute stress, as well as an attenuated vasodilatory reaction. These effects could not be accounted for in terms of group differences in stress task performance, subjective task impact/engagement, age, BMI, neuroticism, cardio-respiratory fitness, or co-morbid exercise dependence. Our findings suggest that disordered eating is characterised by a dysregulation of the autonomic stress-response system. As such, they add further weight to the general contention that blunted stress reactivity is characteristic of a number of maladaptive behaviours and states.

Cardiovascular and cortisol reactions to acute psychological stress and cognitive ability in the Dutch Famine Birth Cohort Study

Given evidence linking blunted cardiovascular and cortisol reactions to acute stress and a range of adverse behavioral outcomes, the present study examined the associations between cardiovascular and cortisol reactivity and cognitive ability measured independently of the stress task exposure. Cognitive ability was assessed using the Alice Heim-4 test of general intelligence and two memory tasks in 724 men and women who were part of the Dutch Famine Birth Cohort Study. Blood pressure and heart rate, as well as cortisol reactivity, were measured to a battery of three standard acute stress tasks. Poorer cognitive ability was associated with lower cardiovascular reactions to stress and lower cortisol area under the curve. Our results are consistent with recent findings implicating low physiological stress reactivity in a range of adverse behavioral and health outcomes.

Do low levels of stress reactivity signal poor states of health?

Studies of cardiovascular disease risk have explored the idea that exaggerated physiological responses to stress may signal increased risk of cardiovascular disease. We describe a neurophysiological model of brain structures and peripheral structures that may contribute to exaggerated reactivity. Level I in this model includes the limbic system and its interactions with the prefrontal cortex that determine stress appraisals and coping responses. Level II addresses the hypothalamus and brainstem that contribute outputs to the body and which also includes brainstem nuclei that feed back to Level I to modulate its functioning. Level III includes the peripheral tissues themselves. We then suggest that stress reactivity ranging from very low to very high has a normative midrange of intensity and present evidence that negative health outcomes may be associated with both exaggerated and diminished stress reactivity since both tendencies imply a loss of homeostatic regulation. In particular, dysregulation at Levels I and II in our heuristic model signify altered motivational function and an attendant alteration in outflow to the periphery and poor behavioral homeostasis. In consequence, poor affective and behavioral regulation would be expected to contribute to poor health behaviors therefore additionally impairing health. In conclusion, diminished as well as exaggerated physiological reactivity should be seen as nonoptimal functioning that can contribute to poor health outcomes. This conceptualization places physical health into the context of behavioral and physiological processes that contribute to homeostasis.

Medial prefrontal cortex damage affects physiological and psychological stress responses differently in men and women

The ability to produce appropriate physiological and psychological responses to stressful situations depends on accurate recognition and appraisal of such situations. Such ability is also important for proper emotion regulation. A number of studies have suggested that the medial prefrontal cortex (mPFC) plays a significant role in emotion regulation, as well as in the control of physiological endpoints of emotion regulation such as the hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system (ANS). Further, recent work has suggested that men and women may differ in these mechanisms of neural control of emotion regulation. Here, we examined the role of the human mPFC in self-report, ANS, and HPA stress reactivity by testing a group of participants with damage to this region (9 women and 9 men), a brain damaged comparison group (6 women and 6 men), and healthy comparison participants (27 women and 27 men) on an orthostatic challenge and the Trier Social Stress Test (TSST). The mPFC participants showed heightened self-reported stress in response to the TSST. In women, mPFC damage led to an increased cortisol response to the TSST. By contrast, in men, greater volume of mPFC damage was correlated with a decreased cortisol response. Finally, men with mPFC damage showed altered autonomic control of the heart (higher heart rate and lower high frequency heart rate variability) during an orthostatic challenge. These findings support the idea that the mPFC is involved in the regulation of physiological and psychological responses to stress and that this regulation may differ between men and women.

Blunted hypothalamic-pituitary-adrenocortical axis responsivity to stress in persons with a family history of alcoholism

Abstinent alcoholics show a blunted stress cortisol response that may be a consequence of drinking or a preexisting risk marker. We tested cortisol responses to psychological stress in 186 18-30 year-old, healthy social drinkers having no personal history of alcohol or drug dependence, 91 of whom had one or two alcoholic parents (FH+) and 95 having no family alcoholism for two generations (FH-). We predicted that, similar to alcoholic patients, the FH+ would have reduced stress cortisol responses that would be partially determined by their temperament characteristics, specifically antisocial tendencies as measured by the California Psychological Inventory. On a stress day, subjects performed continuous simulated public speaking and mental arithmetic tasks for 45 min, and on a control day they sat and rested for the same time period. The FH+ who were low in sociability had smaller cortisol responses than FH-, high-sociability persons (t=2.27, p=.02). These two groups were not different in diurnal cortisol secretion patterns or affective responses to the stressors. Persons with a familial risk for alcoholism who have more antisocial tendencies may have altered central nervous system responses to emotionally relevant social challenges. Disrupted cortisol stress responses may serve as a risk marker for the development of substance use disorders.

SALIVARY CORTISOL: A PREDICTOR OF CONVICTIONS FOR DRIVING UNDER THE INFLUENCE OF ALCOHOL?

AIMS

To examine the relationship between salivary cortisol and frequency of past driving under the influence of alcohol (DUI) convictions.

METHODS

A total of 104 males with previous DUI convictions (from one to eight) and mean age of 44.7 years were assessed on measures characterizing repeat DUI offenders, including sociodemographic information, alcohol use behaviours, biological indices of the organic consequences of chronic abuse, negative consequences of excessive drinking, past DUI conviction history, impulse control, and antisocial behaviour tendencies. Saliva samples were taken approximately every 30 min over a 6 h period during an exhaustive multidimensional assessment protocol, and were then assayed to obtain cortisol responses.

RESULTS

Blunted cortisol response, typically observed in alcoholics and in high-risk non-alcoholics, was associated with increased number of past DUI convictions. This association was particularly pronounced in multiple DUI offenders, and was stronger than, and independent of, other measures of alcohol use severity and chronicity commonly used for DUI assessment.

CONCLUSIONS

Cortisol response may be useful in understanding the mediators underlying repeat DUI offending and the frequent failure of intervention efforts in curbing DUI behaviour.

Sleep deprivation potentiates activation of cardiovascular and catecholamine responses in abstinent alcoholics

Alcohol dependence is associated with an increased incidence of hypertension and cardiac arrhythmias, but the triggering mechanisms are not known. Sleep loss, common in alcohol-dependent patients, causes an activation of the sympathetic nervous system. To determine whether sleep deprivation induces differential cardiovascular and sympathetic responses in alcohol dependence, we measured heart rate, blood pressure, and circulating sympathetic catecholamines in 36 abstinent alcohol-dependent men and 36 age-, gender-, and ethnicity-matched controls after a baseline night of sleep, in the morning after early night partial sleep deprivation, and again after a full night of recovery sleep. Subjects were on average normotensive and none was being treated for hypertension. Baseline heart rate, blood pressure, and sympathetic catecholamines were similar in the 2 groups. Administration of partial night sleep deprivation induced greater increases of heart rate (P<0.01) and circulating levels of norepinephrine (P<0.05) and epinephrine (P<0.05) in the alcohol-dependent men as compared with responses in controls. Even after a full night of recovery sleep, elevations in heart rate (P<0.05) and circulating catecholamines (P<0.05) persisted in the alcoholic subjects. Partial night sleep deprivation induces elevated heart rate and sympathetic catecholamine responses in alcoholic subjects as compared with controls, and this sympathetic activation is sustained after nights of partial and recovery sleep. It is possible that modest habitual sleep loss could contribute to triggering cardiac arrhythmias or other cardiovascular events in alcohol dependence.