Cortisol responses to naturalistic and laboratory stress in student teachers: comparison with a non-stress control day

Stress in the collective: Psychophysiological reactivity to an orchestra concert as a collective naturalistic, real-life stressor of psychosocial nature

BACKGROUND & OBJECTIVES

The investigation of collective stress experiences, including collective stressors and the psychophysiological reactivity of a collective to these stressors, has been widely neglected so far. Here, we examined public non-professional orchestra concerts as collective naturalistic, real-life stressors of psychosocial nature and the resulting psychophysiological reactivity in a collective of non-professional orchestra musicians.

METHODS

The members of two non-professional music orchestras (N = 54) were accompanied during a public concert (stress condition) and a rehearsal (control condition). We repeatedly assessed heart rate, salivary cortisol, and excitement levels before, during, and after the concert/rehearsal in addition to the anticipatory cognitive stress appraisal.

RESULTS

We observed greater physiological reactivity to the concert compared to the rehearsal (p's ≤.017), with higher increases in heart rate levels in anticipation of and in reaction to the concert and in cortisol levels in reaction to the concert compared to the rehearsal. Moreover, orchestra members reported greater psychological reactivity to the concert than to the rehearsal (p's ≤.024) in terms of higher cognitive stress appraisal in anticipation and increased excitement levels before and during the concert compared to the rehearsal.

DISCUSSION

Our findings indicate that orchestra concerts by non-professional musicians constitute collective naturalistic, real-life stressors of psychosocial nature, resulting in significant psychophysiological stress responses with reactivity kinetics differing between the sympathetic-adrenal-medullary axis, the hypothalamic-pituitary-adrenal axis, and the psychological response. Potential implications and modulating factors need to be elucidated in future studies.

When virtual reality becomes psychoneuroendocrine reality: A stress(or) review

This review article was awarded the Dirk Hellhammer award from ISPNE in 2023. It explores the dynamic relationship between stressors and stress from a historical view as well as a vision towards the future of stress research via virtual reality (VR). We introduce the concept of a "syncytium," a permeable boundary that blurs the distinction between stress and stressor, in order to understand why the field of stress biology continues to inadequately measure stress alone as a proxy for the force of external stressors. Using Virtual Reality (VR) as an illustrative example to explicate the black box of stressors, we examine the distinction between 'immersion' and 'presence' as analogous terms for stressor and stress, respectively. We argue that the conventional psychological approaches to stress measurement and appraisal theory unfortunately fall short in quantifying the force of the stressor, leading to reverse causality fallacies. Further, the concept of affordances is introduced as an ecological or holistic tool to measure and design a stressor's force, bridging the gap between the external environment and an individual's physiological response to stress. Affordances also serve to ameliorate shortcomings in stress appraisal by integrating ecological interdependencies. By combining VR and psychobiological measures, this paper aims to unravel the complexity of the stressor-stress syncytium, highlighting the necessity of assessing both the internal and external facets to gain a holistic understanding of stress physiology and shift away from reverse causality reasoning. We find that the utility of VR extends beyond presence to include affordance-based measures of immersion, which can effectively model stressor force. Future research should prioritize the development of tools that can measure both immersion and presence, thereby providing a more comprehensive understanding of how external stressors interact with individual psychological states.

How is momentary well-being and stress associated in persons with spinal cord injury and their romantic partners? A study protocol for a dyadic everyday life study

INTRODUCTION

Very little is known about daily life dynamics and mutual influences that tie together well-being and psychobiological stress responses in persons with spinal cord injury (SCI) and their romantic partners in particular. The role of social support and physical activity in the associations between emotional well-being and stress has not been investigated in the context of SCI yet and studies applying a dyadic approach, exploring the role of a romantic partner, are currently unavailable. The overall objective is thus to better understand the interplay between emotional well-being and the psychobiological stress marker cortisol, and to investigate the potentially moderating role of social support and physical activity in the well-being-stress association among persons with SCI and their romantic partners using a dyadic perspective.

METHODS AND ANALYSIS

The stRess and Health Among romantic couPles with Spinal cOrD injurY study, funded by the Swiss National Science Foundation (10001C_204739), aims to recruit N=150 community-dwelling persons with SCI and their romantic partners including three phases of data collection. The first phase includes a baseline questionnaire. The second phase, the time sampling phase, comprises an ecological momentary assessment design in the everyday life of couples where both partners provide concurrent salivary cortisol samples five times a day and complete assessments four times a day over seven consecutive days. Wrist-worn accelerometers record physical activity during this period. The third phase is an observational study in the laboratory, where a couples' discussion on the SCI management in their everyday life is recorded and coded to identify a couple-specific coping with SCI to enrich data. The dyadic data will be analysed using multilevel modelling, based on the actor-partner interdependence model framework.

ETHICS AND DISSEMINATION

The study was approved by the ethics committee of Northwest and Central Switzerland (2022-01072) and findings will be disseminated through peer-reviewed publications and conference presentations.

Associations of diurnal cortisol parameters with cortisol stress reactivity and recovery: A systematic review and meta-analysis

Researchers commonly assess the functioning of the hypothalamic-pituitary-adrenal (HPA) axis by measuring natural fluctuations of its end product cortisol throughout the day or in response to a standardized stressor. Although it is conceivable that an individual releasing relatively more cortisol when confronted with a laboratory stressor does the same in everyday life, inconsistencies remain in the literature regarding associations between diurnal cortisol parameters and cortisol stress responses. Hence, the current meta-analysis aggregated findings of 12 studies to examine overall associations of diurnal cortisol parameters (including total output, diurnal slope, and cortisol awakening response [CAR]) with cortisol stress reactivity and recovery in the Trier Social Stress Test (TSST). There were no significant overall associations of total output, slope, or CAR with stress reactivity. Lower total diurnal cortisol output was significantly related to better stress recovery, whereas diurnal slope and CAR were unrelated to stress recovery. Moderation analyses revealed that associations between diurnal cortisol and cortisol stress responses were dependent on the computation method of cortisol parameters, questioning the convergence and validity of commonly employed measures of stress reactivity and recovery. Overall, it seems that we cannot predict characteristics of the diurnal cortisol rhythm from a one-time measure of stress reactivity in a standardized psychosocial laboratory paradigm.

Associations between emotion reactivity to daily interpersonal stress and acute social-evaluative stress during late adolescence

Emotion reactivity refers to the intensity of changes in positive and negative emotion following a stimulus, typically studied with respect to daily stressors (e.g., arguments, demands) or laboratory stressors, including the Trier Social Stress Test (TSST). Yet, it is unclear whether emotion reactivity to daily and to laboratory stressors are related. The present study examined whether greater emotion reactivity to daily stressors (i.e., arguments, demands) is associated with greater reactivity to the TSST. Late adolescents (N = 82; Mage = 18.35, SD = 0.51, range 17-19; 56.1% female; 65.9% Latine, 34.2% European American) reported whether they experienced arguments and demands with friends, family, and individuals at school and their negative and positive emotion nightly for 15 days. They also completed the TSST, a validated paradigm for eliciting social-evaluative threat, and reported their emotion at baseline and immediately post-TSST. Multilevel models examined whether daily and laboratory emotion reactivity were related by testing whether the daily associations between arguments and demands with emotion differed by emotion reactivity to the TSST. Individuals with greater positive emotion reactivity (i.e., greater reductions in positive emotion) and greater negative emotion reactivity to the TSST showed greater positive emotion reactivity to daily demands. Emotion reactivity to the TSST was not significantly related to emotion reactivity to arguments. Findings provide preliminary evidence that emotion reactivity to the TSST relates to some aspects of daily emotion reactivity, with relations differing depending on type of daily stressor and valence of emotion. Results contextualise the implications of emotion reactivity to the TSST for daily stress processes.

Comparison of the Perceived Stress Reactivity Scale with physiological and self-reported stress responses during ecological momentary assessment and during participation in a virtual reality version of the Trier Social Stress Test

Valid approaches to conveniently measure stress reactivity are needed due to the growing evidence of its health-impairing effects. This study examined whether the Perceived Stress Reactivity Scale (PSRS) predicts cardiovascular and psychological responses to psychosocial stressors during daily life and during a virtual reality (VR) Trier Social Stress Test (TSST). Medical students answered a standardized baseline questionnaire to assess perceived stress reactivity by the PSRS. The PSRS asks participants to rate the intensity of their typical affective responses to common stressors during daily life. They were further asked to participate in a VR-TSST and in an ecological momentary assessment (EMA) over a period of three consecutive workdays during daily life. Blood pressure and self-reported stress were repeatedly, heart rate variability (HRV) continuously measured during the VR-TSST and EMA. Furthermore, participants repeatedly assessed task demands, task control and social conflict during the EMA. Data was analysed using multilevel analysis and multiple linear regression. Results indicate that the PSRS moderates associations between blood pressure (but not HRV) and demands and control during daily life. Furthermore, the PSRS directly predicted self-reported stress, but did not moderate associations between self-reported stress and demands, control and social conflict. The PSRS did not predict physiological and self-reported stress responses to the VR-TSST. This study partly confirmed convergent validity of the PSRS to stress reactivity in daily life. Furthermore, the lack of association between the PSRS and stress responses to the VR-TSST calls for future studies to search for reliable and valid ways to assess stress reactivity.

Psychological Stress = Physiological Stress?

Abstract. The present study analyzed experimentally the association between the experience of psychological stress and the physiological stress response of prospective teachers. The experienced stress was assessed by self-reported data. Cortisol concentrations via saliva samples reflected the physiological response. The results show no difference between the stress and the control group in the experience of psychological stress. However, the stress group had significantly increased cortisol concentrations compared to the control group. The study could not show any correlation between the two stress parameters. The results suggest that a stress response should be validated based not only on the experience of psychological stress but also on the physiological stress response. This is particularly crucial in light of the fact that the majority of studies concerning stress in teachers are limited to experiences of psychological stress so far. Due to this, the results may provide a first important contribution to a more comprehensive stress assessment for teachers.

What Does Sleeping Brain Tell About Stress? A Pilot Functional Near-Infrared Spectroscopy Study Into Stress-Related Cortical Hemodynamic Features During Sleep

People with mental stress often experience disturbed sleep, suggesting stress-related abnormalities in brain activity during sleep. However, no study has looked at the physiological oscillations in brain hemodynamics during sleep in relation to stress. In this pilot study, we aimed to explore the relationships between bedtime stress and the hemodynamics in the prefrontal cortex during the first sleep cycle. We tracked the stress biomarkers, salivary cortisol, and secretory immunoglobulin A (sIgA) on a daily basis and utilized the days of lower levels of measured stress as natural controls to the days of higher levels of measured stress. Cortical hemodynamics was measured using a cutting-edge wearable functional near-infrared spectroscopy (fNIRS) system. Time-domain, frequency-domain features as well as nonlinear features were derived from the cleaned hemodynamic signals. We proposed an original ensemble algorithm to generate an average importance score for each feature based on the assessment of six statistical and machine learning techniques. With all channels counted in, the top five most referred feature types are Hurst exponent, mean, the ratio of the major/minor axis standard deviation of the Poincaré plot of the signal, statistical complexity, and crest factor. The left rostral prefrontal cortex (RLPFC) was the most relevant sub-region. Significantly strong correlations were found between the hemodynamic features derived at this sub-region and all three stress indicators. The dorsolateral prefrontal cortex (DLPFC) is also a relevant cortical area. The areas of mid-DLPFC and caudal-DLPFC both demonstrated significant and moderate association to all three stress indicators. No relevance was found in the ventrolateral prefrontal cortex. The preliminary results shed light on the possible role of the RLPCF, especially the left RLPCF, in processing stress during sleep. In addition, our findings echoed the previous stress studies conducted during wake time and provides supplementary evidence on the relevance of the dorsolateral prefrontal cortex in stress responses during sleep. This pilot study serves as a proof-of-concept for a new research paradigm to stress research and identified exciting opportunities for future studies.

Effects of Overtraining Status on the Cortisol Awakening Response-Endocrine and Metabolic Responses on Overtraining Syndrome (EROS-CAR)

The cortisol awakening response (CAR) is a distinct component of the circadian cortisol profile and has promise as a biomarker for the monitoring of athlete readiness and training status. Although some studies have suggested the CAR may be affected by the development of overtraining syndrome (OTS), this has yet to be systematically investigated.

PURPOSE

To compare the CAR and diurnal cortisol slope between athletes diagnosed with OTS, healthy athletes, and sedentary controls.

METHODS

This study was a secondary analysis of data from the Endocrine and Metabolic Responses on Overtraining study. Male participants were recruited to either OTS, healthy athlete, or sedentary control groups. The participants produced saliva samples immediately after waking (S1), 30 minutes after waking (S2), at 16:00 hours, and at 23:00 hours. Salivary cortisol concentration was determined by an electrochemiluminescence assay. Mixed-effects models were used to assess the conditional effect of group (sedentary controls, OTS, and healthy athletes) on the change in cortisol over time. Separate models were fit for the awakening samples (S1 and S2) and for the diurnal slope (linear change across S1, 16:00 h, and 23:00 h).

RESULTS

The models demonstrated significant time-by-group interaction for OTS for the 2 cortisol concentrations collected during the awakening period (β = -9.33, P < .001), but not for the diurnal cortisol slope (β = 0.02, P = .80).

CONCLUSIONS

These results suggest the CAR may be associated with OTS and should be considered within a panel of biomarkers. Further research is necessary to determine whether alterations in the CAR may precede the diagnosis of OTS.

Association of the HPA axis response to upcoming competition and shooting outcomes in elite junior shooting players

Successful shooting performance in competition is reliant on several factors such as shooting techniques and competition-associated psychological stresses. This study examined the hypothalamus-pituitary-adrenal (HPA) axis response to upcoming competition and its association with shooting outcomes in elite junior shooting players. The cortisol awakening response (CAR) and dehydroepiandrosterone (DHEA) secretion after awakening were measured for two consecutive days (the day before and on the day of competition for the selection of national shooting team members) in 19 junior men and 21 junior women players, and the shooting scores of the individual players were obtained. The total cortisol secretion during the CAR period (CARauc) increased, but total DHEA secretion during the post-awakening period (Dauc_awk) decreased on the day of competition, compared with one day before competition. The CARauc was higher in women than in men players, whereas Dauc_awk was higher in men than in women players across the two consecutive days. Cortisol and DHEA levels were comparable between low-scored (below the mean scores for air pistol or air rifle players) and high-scored players one day before competition. However, the CARauc on the day of competition was higher and the variations in the CARauc and molar CARauc/Dauc_awk ratios across the two consecutive days were greater in low-scored than in high-scored men and women players. These results indicated that upcoming competition involves alterations of the CAR and DHEA secretion after the awakening period, and greater HPA response to the upcoming competition was adversely associated with shooting scores in junior shooting athletes.Lay summaryAn important upcoming competition was perceived as a strong stressor on awakening that induced alteration in CAR and DHEA secretion after the awakening period in elite shooting players. This study observed that, irrespective of their age and period of shooting practice, the HPA axis function on the day of competition was associated with shooting outcomes in elite shooting players.

Minimally-invasive methods for examining biological changes in response to chronic stress: A scoping review

BACKGROUND

Nurse researchers are increasingly interested in incorporating biological indicators related to chronic stress, or repeated or constant exposure to psychological stressors. Minimally invasive collection methods may improve access to vulnerable populations.

OBJECTIVE

To map biological indicators measured through minimally invasive methods investigating biological changes in response to chronic stress.

DESIGN, DATA SOURCES, AND METHODS

The paper seeks to answer two questions: What are the characteristics of the minimally-invasive methods used to measure the biological correlates of chronic stress? What are the limitations regarding the use of the minimally-invasive methods and/or biological indicators identified above? Authors completed a scoping review following guidelines from the Joanna Briggs Institute Manual and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for Scoping Reviews. A literature search was completed in PubMed, PsycINFO, and Scopus. 2518 articles were screened and 145 studies were included. Data were extracted using a standardized extraction tool, compiled, and coded.

RESULTS

Studies included minimally-invasive methods to measure the hypothalamic-adrenal-pituitary axis (N = 173), immune and inflammatory markers (N = 118), and adult neurogenesis (N = 6). Cortisol was most frequently measured (N = 136), usually in saliva (N = 86). Studies included a variety of limitations for the methods and indicators, including concerns about timing and accuracy of collection, frequency of sampling, and controlling for acute stressors.

CONCLUSIONS

Nurse researchers have access to many minimally-invasive methods to measure altered biological processes related to chronic stress. A gap identified by this review is the paucity of minimally-invasive methods for investigating neurogenesis; the measurement of brain derived neurotrophic factor in plasma is a distal proxy and further research is needed to test the response of peripheral levels to psychosocial stress interventions. Additionally, while this scoping review allows nurse researchers to consider possible biological indicators to include in their research, future research is still needed on some of the basic premises of stress research, including agreement on the conceptualization of chronic stress.

Competition Stress Leads to a Blunting of the Cortisol Awakening Response in Elite Rowers

Background: Anticipation of forthcoming demands is often met with biological up-regulation, for example, levels of the stress hormone cortisol are typically elevated immediately prior to an anticipated event. Similarly, the cortisol awakening response (CAR), a surge in cortisol in the period following waking, is elevated on days of anticipated demand and this is viewed as an adaptive response in the preparation for challenge. This study assessed the effects of competition as an anticipated challenge in elite rowers. Methods: Elite rowers (N = 8) were assessed during two training and two competition weekends. Each assessment involved the measurement of self-reported competitive (cognitive and somatic) anxiety and salivary diurnal cortisol across 2 days representing a preparation day prior to either a training or competition day. Competitive anxiety was measured each morning and saliva samples were provided immediately upon waking and 30 min post waking (CAR) and before bed. Results: Self-reported cognitive and somatic anxiety levels were significantly greater during the competition phase compared with training. Additionally, levels of cognitive anxiety were greater on the day of competition compared with the preparation day. CAR magnitude was significantly reduced during the competition phase compared with training; however, there were no differences between preparation and event days. Conclusions: Reduced or blunted CARs are typically observed in chronically stressed populations and are characteristic of burnout and fatigue. While an increased CAR during competition may represent an adaptive response to challenge, blunted CARs and the concomitant increases in competitive anxiety observed here indicate maladaptive responding during a period where maximized functioning is critical.

Effects of Noradrenergic Stimulation Upon Context-Related Extinction Learning Performance and BOLD Activation in Hippocampus and Prefrontal Cortex Differ Between Participants Showing and Not Showing Renewal

While the neural structures mediating context-related renewal of extinction are well established, the neurotransmitter systems processing renewal remain elusive. Noradrenergic stimulation before extinction improved learning, but did not alter renewal. Since context processing already during initial conditioning can influence renewal, in this fMRI study we investigated how noradrenergic stimulation by a single dose of atomoxetine (ATO) before initial acquisition of a context-related predictive-learning task affects subsequent learning and renewal in humans. ATO participants showing contextual renewal (REN) exhibited a selective extinction learning deficit compared to placebo (PLAC) and ATO participants lacking renewal (ATO NoREN), probably owing to formation of more stable associations during acquisition. New learning and retrieval during the extinction phase as well as initial acquisition were unimpaired. In ATO REN, higher activation in right inferior frontal gyrus (iFG) during acquisition may have supported the formation of more stable associations, while reduced activation in hippocampus and left iFG during extinction was associated with impaired context encoding and response inhibition. During recall, ATO REN showed reduced overall context-dependent renewal associated with higher activation in medial PFC and right hippocampus. The results demonstrate the importance of noradrenergic processing in inferior frontal cortex and hippocampus for human extinction learning, but not necessarily initial conditioning. Since an identical atomoxetine treatment evoked diverging blood-oxygen level dependent (BOLD) activation patterns in REN and NoREN participants, the effect is presumably related to the participants’ preferred processing strategies that may have recruited differentially interconnected networks in which noradrenergic stimulation produced diverging consequences. In the ATO REN group, probably an additive effect of their preferred processing strategy, which pre-activated the noradrenergic system, and the experimental treatment caused a shift beyond the optimal working range of the noradrenergic system, thus modulating BOLD activation in a way that impaired extinction learning and recall.

Resilience characteristics and prior life stress determine anticipatory response to acute social stress in children aged 7-11 years

OBJECTIVES

To assess the interplay of prior life stress and characteristics of resilience in determining how children cope with potentially stressful situations, using a two-phase study that triangulates parent-child dyadic interview data with subsequent experience of an acute laboratory stressor in 7-11-year-olds.

METHODS

Participants (n = 34) were designated as being in one of four groups based on high/low levels of prior stress experience and high/low resilience ratings assessed during at-home interviews and from questionnaires measuring recent life events, hassles, and trait coping. During a subsequent laboratory stress protocol, salivary cortisol and heart rate were monitored, and a verbal subjective report was provided.

RESULTS

Salivary cortisol showed a significant increase in anticipation of the stress test, heart rate increased during the test, and children self-reported the task as stressful. Males displayed higher levels of cortisol than females in the anticipatory period. We observed no increase in salivary cortisol in response to the stress testing phase. Using the stress/resilience categorization, children with a higher level of resilience were differentiated by cortisol level in anticipation of the acute stress experiment based on their level of prior life stress. Highly resilient children with greater experience of prior life stress showed a lower anticipatory cortisol response than highly resilient children with less experience of prior life stress.

CONCLUSIONS

This study highlights the relevance of contextual factors, such as prior stress experience and resilience, in physiological response to the anticipation of acute stress and has implications for understanding how children cope with stressful experiences. Statement of contribution What is already known on this subject? An adaptation to the stress testing paradigm, the Bath Experimental Stress Test for Children (BEST-C) was found to reliably induce a salivary cortisol response in young children, suggesting that peer matching the audience was an effective modification to laboratory social stress testing. Recent work focusing on early life adversity has seen the emergence of prior stress experience and resilience as key factors in the examination of acute stress responses. However, much of the research regarding the impact of childhood stress is ambiguous; some research suggests that if children have experienced prior stressful life events this will enact a positive effect on stress responses and lead to resilience, and other research suggested that it will have a compounding negative effect. What does the study add? Findings provide support for the capacity of the BEST-C to induce an anticipation stress response in children. Contextual factors e.g., prior stress experience and resilience are key for understanding stress responses. Resilient children with more experience of stress show lower cortisol than those with less stress experience.

Influence of Regular Physical Activity and Fitness on Stress Reactivity as Measured with the Trier Social Stress Test Protocol: A Systematic Review

BACKGROUND

Psychosocial stress is associated with multiple health complaints. Research to date suggests that regular physical activity (PA) and higher cardiorespiratory fitness may reduce stress reactivity and therefore contribute to a reduction of stress-related risk factors. While previous reviews have not differentiated between stressors, we focus on psychosocial stress elicited with the Trier Social Stress Test (TSST).

OBJECTIVE

Our objective was to examine the effect of regular PA and cardiorespiratory fitness on stress reactivity, with a particular focus on the TSST. The TSST is the laboratory task most widely used to induce socio-evaluative stress and elicits stronger stress reactions than most other cognitive stressor tasks.

METHODS

A systematic search within various databases was performed in January 2018. The following outcomes were considered: cortisol, heart rate, psychological stress reactivity, and potential moderators (age, sex, exercise intensity, assessment mode, and psychological constructs).

RESULTS

In total, 14 eligible studies were identified. Cortisol and heart rate reactivity were attenuated by higher PA or better fitness in seven of twelve studies and four of nine studies, respectively. Two of four studies reported smaller increases in anxiety and smaller decreases in calmness in physically active/fitter participants. Three of four studies found that higher PA/fitness was associated with more favorable mood in response to the TSST.

CONCLUSION

About half of the studies suggested that higher PA/fitness levels were associated with an attenuated response to psychosocial stress. Currently, most evidence is based on cross-sectional analyses. Therefore, a great need for further studies with longitudinal or experimental designs exists.

Hair cortisol concentrations in a Spanish sample of healthy adults

BACKGROUND

Hair cortisol concentration (HCC), as a novel promising method to retrospectively measure hypothalamic-pituitary-adrenal (HPA) axis activation, is being increasingly studied. We tested the relationships between HCC and a range of possible confounding variables in a Spanish sample of healthy adults and pregnant women.

METHODS

The number of healthy adults who participated in the study was 529, being 270 males and 259 females, with a combined mean age of 37.88 years (SD = 15.66). Additionally, a separate sample of 62 pregnant women was also recruited with a mean age of 32.95 (SD = 3.67), and in the first trimester of pregnancy. Each participant was interviewed before the study to obtain sociodemographic and lifestyle variables, and a hair sample was taken from the posterior vertex of the head, cut as close to the scalp as possible. Assuming the average growth rate of head hair is 1 cm per month, a 3-cm segment was analysed, in order to measure the cortisol concentrations from a three-month period. For the pregnant women, hair samples for each trimester of pregnancy were analysed.

RESULTS

The mean hair cortisol concentration was 127.91 (111.52) pg/mg for the general sample. The variables of age, education, employment status, use of hair dyes, use of oral contraceptives, and physical exercise had a significant relation to HCC. When adjusted for further variables, only education and physical exercise remained statistically significant. When including the use of oral contraceptives and only with respect to females, only physical exercise remains statistically significant. For the subsample of pregnant woman, the mean hair cortisol concentration was 334.51 (409.77) pg/mg for the first trimester, 302.18 (270.24) pg/mg for the second trimester, and 331.31 (295.46) pg/mg for the third trimester of pregnancy. None of the assessed confounding variables (age, body mass index, previous miscarriages, employment status, hair dyes, dependent children and physical exercise), except education level, was related to HCC.

CONCLUSIONS

In this sample of healthy Spaniards, results suggested an association between HCC and physical exercise and educational level. In pregnant women, the prevalence of HCC was higher than in non-pregnant woman, and was related to educational level. This study emphasises the need to determine the relationship between HCC and confounders such as sociodemographic and lifestyle variables in the general population and specific groups formed by individuals such as pregnant women.

Is cortisol production in response to an acute stressor associated with diurnal cortisol production during adolescence?

The goal of the current study was to examine the extent to which cortisol responding to an acute stressor is related to diurnal cortisol patterns during adolescence. Participants were 105 adolescents (10-17 years of age) who experienced a robust social-evaluative stressor and provided saliva samples (before and immediately after, as well as 10, 20, and 30 min after the stressor) to assess both cortisol reactivity and recovery and also provided saliva samples (at wake-up, 30 min after wake-up, 4 pm, and at bedtime) on two consecutive days to measure diurnal cortisol production. Dual process latent growth curve models, one for cortisol reactivity and one for diurnal cortisol, indicated that dampened cortisol reactivity and prolonged cortisol recovery (i.e., less cortisol produced during reactivity but more cortisol produced during recovery) were associated with dampened decreases in cortisol production across the day, suggesting that adolescents are likely to show attenuation in multiple components of HPA axis functioning.

Salivary cortisol and alpha-amylase: Is there consistency between psychosocial stress test and burdensome work shifts?

This study examined the consistency of salivary cortisol and alpha-amylase (sAA) total daily secretion between laboratory and field circumstances. The 95 participants were shift working female health care professionals with high (n = 53) or low (n = 42) psychosocial stress (job strain) measured by the Job Content Questionnaire (JCQ). The Trier Social Stress Test including a 5-min free speech and a mental arithmetic task was conducted with four, and field measurements with three daily saliva samples of cortisol and sAA during circadian rhythm and inter-shift recovery controlled morning shift, night shift, and a day off. The associations of salivary cortisol and sAA area under the curve with respect to ground (AUCg) and area under the curve with respect to increase (AUCi) between laboratory and field were tested using OLS (Ordinary Least Squares) regression. The sAA AUCg output in the laboratory was correlated with the output during all field measurement days and similarly among high and low job strain groups (p < 0.001). SAA AUCi and salivary cortisol AUCg and AUCi were not correlated between laboratory and field measurement, neither in the whole sample nor among the low or high job strain group. In conclusion, a laboratory measure of sAA AUCg output is promising in predicting stress-related output during burdensome work shifts and leisure time, whereas sAA AUCi or salivary cortisol seem not to have this potential.

Analyses of hair and salivary cortisol for evaluating hypothalamic-pituitary-adrenal axis activation in patients with autoimmune disease

Although many studies have shown that patients with autoimmune disease present a hypoactive hypothalamic-pituitary-adrenal axis (HPA), controversial results have been described. Our objective was to study HPA axis activity in women with autoimmune disease compared to healthy women. Therefore, we analyzed salivary cortisol over the course of a day, and hair cortisol concentrations from the three preceding months, from 65 women divided into two groups: healthy women (n = 30), with a mean age of 44.70 ± 11.65 years; and women with autoimmune disease (n = 35), with a mean age of 48.26 ± 9.04 years. The latter group comprises women with systemic lupus erythematosus (SLE), Sjögren's syndrome (SS), and systemic sclerosis (SSc). Perceived stress and psychopathological symptomatology were also evaluated. Autoimmune disease group scored higher on the somatization subscale SCL-90-R and lower on the anxiety subscale than the control group. Regarding HPA axis activation, the area under curve for cortisol levels during the day was higher for the autoimmune disease group. In addition, higher cortisol levels in hair were found in the group with autoimmune disease. Our findings show greater short and long-term HPA axis activity in women with autoimmune disease than in healthy women.

Psychosocial functioning and the cortisol awakening response: Meta-analysis, P-curve analysis, and evaluation of the evidential value in existing studies

Cortisol levels rise immediately after awakening and peak approximately 30-45min thereafter. Psychosocial functioning influences this cortisol awakening response (CAR), but there is considerable heterogeneity in the literature. The current study used p-curve and meta-analysis on 709 findings from 212 studies to test the evidential value and estimate effect sizes of four sets of findings: those associating worse psychosocial functioning with higher or lower cortisol increase relative to the waking period (CARi) and to the output of the waking period (AUCw). All four sets of findings demonstrated evidential value. Psychosocial predictors explained 1%-3.6% of variance in CARi and AUCw responses. Based on these effect sizes, cross-sectional studies assessing CAR would need a minimum sample size of 617-783 to detect true effects with 80% power. Depression was linked to higher AUCw and posttraumatic stress to lower AUCw, whereas inconclusive results were obtained for predictor-specific effects on CARi. Suggestions for future CAR research are discussed.

Sex differences in salivary cortisol reactivity to the Trier Social Stress Test (TSST): A meta-analysis

Some, but not all studies using the Trier Social Stress Test (TSST) have demonstrated evidence in support of sex differences in salivary cortisol. The aim of the current meta-analysis is to examine sex differences in salivary cortisol following exposure to the TSST. We further explored the effects of modifications to the TSST protocol and procedural variations as potential moderators. We searched articles published from January, 1993 to February, 2016 in MedLine, PsychINFO, and ProQuest Theses and Dissertations. This meta-analysis is based on 34 studies, with a total sample size of 1350 individuals (640 women and 710 men). Using a random effects model, we found significant heterogeneity in salivary cortisol output across sexes, such that men were observed to have higher cortisol values at peak and recovery following the TSST compared to women. Modifications to the sampling trajectory of cortisol (i.e., duration of acclimation, peak sampling time, and duration of recovery) significantly moderated the heterogeneity across both sexes. Further, there are observed sex differences at various time points of the reactive cortisol following the TSST. Lastly, current results suggest that these sex differences can be, at least in part, attributed to variations in methodological considerations across studies. Future research could advance this line of inquiry by using other methods of analyses (e.g., area under the curve; AUC), in order to better understand the effects of methodological variations and their implications for research design.

Hair and stress: A pilot study of hair and cytokine balance alteration in healthy young women under major exam stress

Mouse models show that experimental stress mimicking prolonged life-stress exposure enhances neurogenic inflammation, induces adaptive immunity cytokine-imbalance characterized by a shift to Type 1 T-helper cell cytokines and increases apoptosis of epithelial cells. This affects hair growth in otherwise healthy animals. In this study, we investigate whether a prolonged naturalistic life-stress exposure affects cytokine balance and hair parameters in healthy humans. 33 (18 exam, 15 comparison) female medical students with comparable sociobiological status were analyzed during a stressful final examination period, at three points in time (T) 12 weeks apart. T1 was before start of the learning period, T2 between the three-day written exam and an oral examination, and T3 after a 12 week rest and recovery from the stress of the examination period. Assessments included: self-reported distress and coping strategies (Perceived Stress Questionnaire [PSQ], Trier Inventory for the Assessment of Chronic Stress [TICS]), COPE), cytokines in supernatants of stimulated peripheral blood mononucleocytes (PBMCs), and trichogram (hair cycle and pigmentation analysis). Comparison between students participating in the final medical exam at T2 and non-exam students, revealed significantly higher stress perception in exam students. Time-wise comparison revealed that stress level, TH1/TH2 cytokine balance and hair parameters changed significantly from T1 to T2 in the exam group, but not the control. However, no group differences were found for cytokine balance or hair parameters at T2. The study concludes that in humans, naturalistic stress, as perceived during participation in a major medical exam, has the potential to shift the immune response to TH1 and transiently hamper hair growth, but these changes stay within a physiological range. Findings are instructive for patients suffering from hair loss in times of high stress. Replication in larger and more diverse sample populations is required, to assess suitability of trichogram analysis as biological outcome for stress studies.

Test Anxiety and Salivary Cortisol Levels in Nursing Students

Stress, in the form of test anxiety, inhibits examination performance essential to nursing success. Salivary cortisol, a biomarker of stress, was obtained before 3 examinations and 1 nursing didactic class from a sample of baccalaureate nursing students in a midwestern US university. Significant differences were found between cortisol sampling events and by junior or senior status. These findings suggest that diverse examinations and program level yield differences in stress for students.

Psychophysiological Assessment of Social Stress in Natural and Laboratory Situations

Abstract. Experience sampling and psychophysiological ambulant assessment methods were employed to compare reactions to social stress using a laboratory stressor (The Trier Social Stress Test [TSST]) or a corresponding real-life condition (seminar presentation). Stress reactions were assessed by self-report as well as additional heart rate (AHR, i.e., heart rate increases corrected for physical activity and initial values) and were compared to a control condition in each group. Twenty-five participants gave a talk in a university seminar course and twenty-two participants took part in the TSST. The TSST elicited a greater overall physiological stress reaction as compared to the seminar presentation. However, analyses of dynamic AHR levels revealed that the groups of speakers showed different response profiles during the time course of the stress situations. AHR levels of both groups were similar at the beginning of the free speech. During the course of their presentation, seminar speakers downregulated their arousal level. The arousal level of TSST participants showed a further increase in the later portion of the TSST during the mental arithmetic task. Thus, the more prominent overall physiological stress reaction during the TSST as compared to the seminar presentation appeared to depend on different demand characteristics rather than on differences of laboratory versus real-life situations per se. The experience of emotional strain was greater in response to the social stressors than in response to control situations in both the TSST and seminar speaker group with no differential effects of the experimental setting (laboratory vs. real life). During the TSST procedure, salivary cortisol concentrations were also assessed. Significant correlations of AHR with cortisol level and subjective experience indicate that AHR measurement provides a valid psychophysiological indicator of social stress. These findings suggest that ambulatory assessment techniques successfully contribute to the validation of a common social stress task.

Testing the ecological validity of the Trier Social Stress Test: Association with real-life exam stress

The Trier Social Stress Test (TSST) is the most widely used laboratory stress protocol in psychoneuroendocrinology. Despite its popularity, surprisingly few attempts have been made to explore the ecological validity of the TSST. In the present study, 31 young healthy subjects (24 females) were exposed to the TSST about 4 weeks before completing an oral exam on a separate day. Salivary cortisol levels increased significantly in response to both stimuli (TSST: F(2.21, 66.33)=5.73, p=0.004; oral exam: F(1.98, 59.28)=4.38, p=0.017) with similar mean response curves and significant correlations between cortisol increases and areas under the response curves (increase: r=0.67; AUC: r=0.56; both p≤0.01). Correspondingly, changes in positive and negative affect did also show significant correlations between conditions (increase: positive affect: r=0.36; negative affect: r=0.50; both: p≤0.05; AUC: positive affect: r=0.81; negative affect: r=0.70; both p≤0.01) while mean time course dynamics were significantly different (positive affect: F(2.55, 76.60)=10.15, p=0.001; negative affect: F(1.56, 46.82)=23.32, p=0.001), indicating that the oral exam had a more pronounced impact on affect than the TSST. Our findings provide new evidence for the view that cortisol as well as subjective stress responses to the TSST are indeed significantly associated with acute stress responses in real life.

Blunted HPA Axis Activity in Suicide Attempters Compared to those at High Risk for Suicidal Behavior

Studies looking at the relationship of the hypothalamic-pituitary-adrenal (HPA) axis to suicidal behavior and its risk factors, such as depression, childhood abuse, and impulsive aggression, report inconsistent results. These studies also do not always differentiate between subjects who go on to attempt suicide, suicidal subjects who never attempted suicide, and non-suicidal subjects with psychiatric disorders. In this study, we examined cortisol responses to an experimental stressor, the Trier Social Stress Test (TSST), in 208 offspring of parents with mood disorder. Offspring suicide attempters showed lower total cortisol output (β=-0.47, 95% CI (-0.83, -0.11), p=0.01) compared with offspring with suicide-related behavior (SRB) but never attempted, non-suicidal offspring, and a healthy control group. The result remained significant even after controlling for sex, age, race, ethnicity, site, socio-economic status, and hour of the day when the TSST was conducted. Suicide attempters also showed lower baseline cortisol before the TSST (β=-0.45, 95% CI (-0.74, -0.17), p=0.002). However, there were no significant differences between the groups on cortisol reactivity to stress (β=4.5, 95% CI (-12.9, 22), p=0.61). Although subjects with suicide attempt and SRB have similar clinical and psychosocial characteristics, this is the first study to differentiate them biologically on HPA axis indices. Blunted HPA axis activity may increase risk for suicide attempt among individuals with psychopathology by reducing their ability to respond adaptively to ongoing stressors. These results may help better identify subjects at high risk for suicidal behavior for targeted prevention and intervention efforts.

Physiological adaptations to chronic stress in healthy humans - why might the sexes have evolved different energy utilisation strategies?

KEY POINTS

The human stress response activates the autonomic nervous system and endocrine systems to increase performance during environmental challenges. This response is usually beneficial, improving the chance of overcoming environmental challenges, but costs resources such as energy. Humans and other animals are known to adapt their responses to acute stress when they are stimulated chronically, presumably to optimise resource utilisation. Characterisation of these adaptations has been limited. Using advanced imaging techniques, we show that cardiovascular and endocrine physiology, reflective of energy utilisation during acute stress, and energy storage (fat) differ between the sexes when they are exposed to chronic stress. We examine possible evolutionary explanations for these differences, related to energy use, and point out how these physiological differences could underpin known disparities between the sexes in their risk of important cardiometabolic disorders such as obesity and cardiovascular disease.

ABSTRACT

Obesity and associated diseases, such as cardiovascular disease, are the dominant human health problems in the modern era. Humans develop these conditions partly because they consume excess energy and exercise too little. Stress might be one of the factors contributing to these disease-promoting behaviours. We postulate that sex-specific primordial energy optimisation strategies exist, which developed to help cope with chronic stress but have become maladaptive in modern societies, worsening health. To demonstrate the existence of these energy optimisation strategies, we recruited 88 healthy adults with varying adiposity and chronic stress exposure. Cardiovascular physiology at rest and during acute stress (Montreal Imaging Stress Task), and body fat distribution were measured using advanced magnetic resonance imaging methods, together with endocrine function, cardiovascular energy use and cognitive performance. Potential confounders such as lifestyle, social class and employment were accounted for. We found that women exposed to chronic stress had lower adiposity, greater acute stress cardiovascular responses and better cognitive performance. Conversely, chronic stress-exposed men had greater adiposity and lower cardiovascular responses to acute stress. These results provide initial support for our hypothesis that differing sex-specific energy conservation strategies exist. We propose that these strategies have initially evolved to benefit humans but are now maladaptive and increase the risk of disorders such as obesity, especially in men exposed to chronic stress.

The effects of an anticipated challenge on diurnal cortisol secretion

In healthy, non-challenged individuals, the secretion of cortisol typically follows a diurnal profile characterized by a peak in the period following waking (cortisol awakening response) and a gradual decline throughout the day. In addition, cortisol secretion is increased in response to acutely stressful stimuli, particularly stressors involving social evaluation. The current study is the first to assess the impact of an anticipated acute laboratory stressor upon the typical diurnal pattern of HPA activation and relationship to acute cortisol secretion. A sample of 23 healthy young adults provided salivary cortisol samples at four time points (immediately upon awakening, 30-min post-awakening, 1200 h and before bed) on 2 consecutive days. On the second day, participants attended the laboratory and undertook an anticipated acute socially evaluative stressor immediately following provision of their 1200 h saliva sample. Heart rate, blood pressure and mood were recorded immediately before and after the stressor and at 10 and 20 min post-stressor along with additional salivary cortisol samples. Typical patterns of cortisol secretion were observed on both days and exposure to the laboratory stressor was associated with the expected increases in cortisol, heart rate, blood pressure and negative mood. However, significant differences in diurnal cortisol secretion were observed between the two days with greater secretion, in particular, during the period following awakening, evident on the day of the anticipated laboratory stressor. Furthermore, secretion of cortisol during the period following awakening was positively related to secretion during the acute reactivity periods. This is the first study to integrate a laboratory stressor into a typical day and assess its impact on indices of diurnal cortisol secretion in an ambulatory setting. The current findings support the notion that the cortisol awakening response is associated with anticipation of the upcoming day and the subsequent demands required of the individual.

Correlates of cortisol in human hair: implications for epidemiologic studies on health effects of chronic stress

Assessment of cortisol concentrations in hair is one of the latest innovations for measuring long-term cortisol exposure. We performed a systematic review of correlates of cortisol in human hair to inform the design, analysis, and interpretation of future epidemiologic studies. Relevant publications were identified through electronic searches on PubMed, WorldCat, and Web of Science using keywords, "cortisol," "hair," "confounders," "chronic," "stress," and "correlates." Thirty-nine studies were included in this review. Notwithstanding scarce data and some inconsistencies, investigators have found hair cortisol concentrations to be associated with stress-related psychiatric symptoms and disorders (e.g., post-traumatic stress disorder), medical conditions indicating chronic activation of the hypothalamic-pituitary-adrenal axis (e.g., Cushing's syndrome), and other life situations associated with elevated risk of chronic stress (e.g., shiftwork). Results from some studies suggest that physical activity, adiposity, and substance abuse may be correlates of hair cortisol concentrations. In contrast to measures of short-term cortisol release (saliva, blood, and urine), cigarette smoking and use of oral contraceptives appear not to be associated with hair cortisol concentrations. Studies of pregnant women indicate increased hair cortisol concentrations across successive trimesters. The study of hair cortisol presents a unique opportunity to assess chronic alterations in cortisol concentrations in epidemiologic studies.

Psychological, endocrine and neural responses to social evaluation in subclinical depression

This study aimed to identify vulnerability patterns in psychological, physiological and neural responses to mild psychosocial challenge in a population that is at a direct risk of developing depression, but who has not as yet succumbed to the full clinical syndrome. A group of healthy and a group of subclinically depressed participants underwent a modified Montreal Imaging Stress task (MIST), a mild neuroimaging psychosocial task and completed state self-esteem and mood measures. Cortisol levels were assessed throughout the session. All participants showed a decrease in performance self-esteem levels following the MIST. Yet, the decline in performance self-esteem levels was associated with increased levels of anxiety and confusion in the healthy group, but increased levels of depression in the subclinical group, following the MIST. The subclinical group showed overall lower cortisol levels compared with the healthy group. The degree of change in activity in the subgenual anterior cingulate cortex in response to negative evaluation was associated with increased levels of depression in the whole sample. Findings suggest that even in response to a mild psychosocial challenge, those individuals vulnerable to depression already show important maladaptive response patterns at psychological and neural levels. The findings point to important targets for future interventions.