Heart rate vARiability and physical activity in inpatient treatMent of burnOut and DepressIon (HARMODI): protocol of a cross-sectional study with up to 8-week follow up.

INTRODUCTION: Chronic stress can cause an imbalance within the autonomic nervous system, thereby affecting cardiovascular and mental health. Physical activity (PA) may have a positive effect on the autonomic nervous system and stress-related disorders, such as depression and burnout. Heart rate variability (HRV) is a non-invasive marker of the autonomic nervous system. However, limited and inconsistent data exist on the exact relationship between HRV, PA and depression and burnout symptoms. The HARMODI study aims to explore whether HRV is a feasible marker of depression and burnout symptoms and aims to evaluate the role of PA in the treatment of stress-related disorders. METHODS AND ANALYSES: This is an observational study with a cross-sectional up to 8 week follow-up study design. A total of 153 patients, undergoing psychiatric inpatient treatment with burnout syndrome (Z73) and depressive episode (F32 or F33) or adjustment disorder (F43.2), will be recruited. Data on depression and burnout symptoms, HRV recordings (24-hour, supine, standing and exercise stress test), cognitive function, cardiorespiratory fitness, cardiovascular health, balance and strength will be collected at baseline (T1) and after up to 8 weeks (T2). Continuous data on PA and Ecological Momentary Assessments of exhaustion, mood and tension will be monitored daily throughout inpatient treatment. Multiple regression models, adjusted for potential confounders, will assess the association between HRV as the primary outcome, PA and depression and burnout severity score. ETHICS AND DISSEMINATION: The protocol has been approved by Swiss Ethics Committee, Cantonal Ethics Committee Zürich. Results of HARMODI will be disseminated through peer-reviewed journals and conference presentations. TRIAL REGISTRATION NUMBER: NCT05874856.

Teachers' perception of aggressive student behavior through the lens of chronic worry and resignation, and its association with psychophysiological stress: An observational study.

Aggressive student behavior is considered a leading risk factor for teacher stress. However, teachers' coping styles may affect how they perceive and respond to aggressive student behavior. This study tests whether teachers' perceptions of aggressive student behavior mainly mirror objectively observed aggression in presence of the teacher (as coded by external observers) or whether teachers' perception of aggressive student behavior primarily reflects teachers' avoidant coping styles, such as chronic worry and resignation. Finally, we examine whether observed and teacher-perceived aggression relates to increased vital exhaustion and psychophysiological stress among teachers (i.e., higher hair cortisol concentration). In an ambulatory assessment study, we administered self-reports to 42 Swiss teachers to assess perceived student aggression, chronic worry, resignation, and vital exhaustion. Additionally, four consecutive lessons per teacher were filmed, and aggressive student behavior in presence of the teacher was coded by four trained external observers. The concentration of cortisol was assessed in hair samples. Results showed that teacher-perceived and observed aggression were moderately associated. Observed aggression was related to teacher perceptions to a much lesser extent than teachers' avoidant coping styles, that is, chronic worry and resignation. While teacher-perceived student aggression was associated with teachers' self-reported vital exhaustion, we did not find any significant association with hair-cortisol concentration. Our findings suggest that teachers perceive student aggression through the lens of their coping styles. Teachers' dysfunctional coping styles are associated with an overestimation of student aggression. Teachers' overestimation of student aggression relates to higher levels of vital exhaustion. Therefore, it is crucial to identify and change teachers' dysfunctional coping styles to prevent a vicious cycle of dysfunctional teacher-student interactions.

Predictors of Psychological Strain and Allostatic Load in Teachers: Examining the Long-Term Effects of Biopsychosocial Risk and Protective Factors Using a LASSO Regression Approach.

Teacher stress significantly challenges teachers' health, teaching quality, and students' motivation and achievement. Thus, it is crucial to identify factors that effectively prevent it. Using a LASSO regression approach, we examined which factors predict teachers' psychological strain and allostatic load over two years. The study included 42 teachers (28 female, Mage = 39.66, SD = 11.99) and three measurement time points: At baseline, we assessed teachers' (a) self-reports (i.e., on personality, coping styles, and psychological strain), (b) behavioral data (i.e., videotaped lessons), and (c) allostatic load (i.e., body mass index, blood pressure, and hair cortisol concentration). At 1- and 2-year follow-ups, psychological strain and allostatic load biomarkers were reassessed. Neuroticism and perceived student disruptions at baseline emerged as the most significant risk factors regarding teachers' psychological strain two years later, while a positive core self-evaluation was the most important protective factor. Perceived support from other teachers and the school administration as well as adaptive coping styles were protective factors against allostatic load after two years. The findings suggest that teachers' psychological strain and allostatic load do not primarily originate from objective classroom conditions but are attributable to teachers' idiosyncratic perception of this environment through the lens of personality and coping strategies.

Associations between stress, resources, and hair cortisol concentration in teachers.

Challenging interactions are the main source of teacher' stress in the classroom. We investigated the association of chronic stress and characteristics of teacher-student interactions with teachers' Hair Cortisol Concentration (HCC). Forty-one teachers (27 women; Mage = 39.65 ± 12.14 years; Mlesson number = 23.15 ± 3.99 lessons per week; grade: elementary, secondary, high, and vocational school teachers) participated in the present study, with participation lasting over the length of one year. HCC was assessed from a 3 cm hair segment near the scalp. Self-reported chronic stress in the last three months was further assessed using the 'Trier Inventory for Chronic Stress' (TICS). Additionally, four consecutive, same-day lectures of each teacher were videotaped and coded offline in an event sampling procedure by trained external observers. The videos were analyzed for two stressors, i.e., classroom disruptions and total student aggression, as well as two resources, i.e., teacher-student relationship and classroom management. Overall, hair samples were collected M = 120.34 days (SD = 84.39) after the distribution of the questionnaires, and M = 67.63 days (SD = 18.40) prior to the observations. Lesson number, classroom disruptions, as well as total student aggression were all significantly positively correlated with HCC. In addition, both teacher-student relationship and classroom management were significantly negatively related to HCC. With regard to self-rated chronic stress, only the TICS subscale 'Pressure to perform' was positively related to HCC. Exploratory moderation analyses revealed that an increasingly good, observed teacher-student relationship buffered the positive association between lesson number and HCC. Our findings show significant associations between HCC and mainly objectively assessable stress, supporting HCC as a biological indicator of chronic stress. In this association, a good relationship between teachers and students acts as a buffer. While the findings underline the importance of examining objective and behavioral data for better understanding the psychobiology of stress, they also support the importance of boostering teachers' (social) resources to increase their overall resilience.

The diurnal course of salivary cortisol and alpha-amylase on workdays and leisure days in teachers and the role of social isolation and neuroticism.

Teachers are among the occupational groups with the highest sick leave rates due to workplace stress and burnout symptoms. A substantial body of research has suggested social isolation and neuroticism to be related to physiological stress activity. However, the relationship between such characteristics and stress experiences has rarely been studied in conjunction with physiological stress indicators in the teachers' natural settings. Thus, the present study examines salivary cortisol and α-amylase as physiological stress indicators on teachers' work and leisure days and their relationship with social isolation. Furthermore, we test whether neuroticism moderates the relationship between social isolation and salivary biomarkers. Forty-two teachers completed questionnaires assessing social isolation (Trier Inventory for the Assessment of Chronic Stress) and neuroticism (Big-Five Inventory). Participants collected eight saliva samples on three days, two workdays, and one leisure day to measure the concentration of cortisol and α-amylase as biomarkers of the hypothalamic-pituitary-adrenal (HPA) axis and the autonomic nervous system (ANS), respectively. Results showed a significantly higher Cortisol Awakening Response (CAR) and diurnal cortisol slope (DCS) on workdays than on the leisure day but no significant differences regarding measures of α-amylase. We found a significant positive relationship between social isolation and the CAR on the leisure day but no association with the α-amylase measures. Furthermore, after controlling for confounders, social isolation was unrelated to neuroticism, and the latter did not moderate between social isolation and the CAR. Our findings suggest an association between social isolation and the HPA axis, i.e., the CAR, but do not support an association with the ANS, which would be indicated by the α-amylase assessments. Finally, our findings could not support an association of neuroticism with the HPA axis and ANS.

An interpretable machine learning approach to multimodal stress detection in a simulated office environment.

BACKGROUND AND OBJECTIVE: Work-related stress affects a large part of today's workforce and is known to have detrimental effects on physical and mental health. Continuous and unobtrusive stress detection may help prevent and reduce stress by providing personalised feedback and allowing for the development of just-in-time adaptive health interventions for stress management. Previous studies on stress detection in work environments have often struggled to adequately reflect real-world conditions in controlled laboratory experiments. To close this gap, in this paper, we present a machine learning methodology for stress detection based on multimodal data collected from unobtrusive sources in an experiment simulating a realistic group office environment (N=90). METHODS: We derive mouse, keyboard and heart rate variability features to detect three levels of perceived stress, valence and arousal with support vector machines, random forests and gradient boosting models using 10-fold cross-validation. We interpret the contributions of features to the model predictions with SHapley Additive exPlanations (SHAP) value plots. RESULTS: The gradient boosting models based on mouse and keyboard features obtained the highest average F1 scores of 0.625, 0.631 and 0.775 for the multiclass prediction of perceived stress, arousal and valence, respectively. Our results indicate that the combination of mouse and keyboard features may be better suited to detect stress in office environments than heart rate variability, despite physiological signal-based stress detection being more established in theory and research. The analysis of SHAP value plots shows that specific mouse movement and typing behaviours may characterise different levels of stress. CONCLUSIONS: Our study fills different methodological gaps in the research on the automated detection of stress in office environments, such as approximating real-life conditions in a laboratory and combining physiological and behavioural data sources. Implications for field studies on personalised, interpretable ML-based systems for the real-time detection of stress in real office environments are also discussed.

Post-awakening salivary alpha-amylase as modulator of treatment response in patients with burnout and major depression.

Around 50% of patients with major depression do not respond to standard first-line treatments, such as psychotherapy and pharmacotherapy. At the same time, a subgroup exhibits altered functioning of stress-responsive bodily systems, such as the central locus coeruleus/sympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis. Given that these systems impact arousal and cognition, it is possible that this subgroup contributes to the high rates of non-responders. Our aim was to investigate whether sympathetic and HPA axis activity modulate treatment outcomes in patients with stress-related major depression. A total of N = 74 inpatients (median age: 50, 62% male) with signs of burnout who fulfilled diagnostic criteria for major depression were recruited. Saliva samples were collected at awakening as well as 30 and 45 min later. Alpha-amylase activity and cortisol concentrations were determined before patients underwent evidence-based multimodal treatment. Non-responders were defined as patients exhibiting a <50% decrease in depression on the Beck Depression Inventory. Non-responders had significantly higher post-awakening alpha-amylase activity than responders (p = .025). In addition, alpha-amylase activity increased significantly over the course of treatment (p = .004), irrespective of responder status. Post-awakening cortisol was neither a predictor nor an indicator of treatment response. If future research confirms alpha-amylase activity as a modulator of treatment response, this may indicate a subgroup of patients with major depression which may benefit from augmentative treatments, such as heart rate variability biofeedback and/or cognitive interventions targeting high arousal.

Longitudinal Associations Between Core Self-Evaluation, Vital Exhaustion and Hair Cortisol in Teachers and the Mediating Effects of Resignation Tendency.

Work-related stress appears to be especially high among teachers. However, most research on teacher stress relies exclusively on teachers' self-reports. Little is known about the physiological correlates of affective stress in teachers. This longitudinal study investigates the relationship between core self-evaluation and adverse psychological and physiological stress outcomes in 42 teachers. Self-report questionnaires were used to assess core self-evaluation, vital exhaustion, and resignation tendency. The concentration of cortisol was assessed using hair samples. One year after the initial measurement, vital exhaustion and hair cortisol were assessed again. Path-analytic mediational models showed that core self-evaluation strongly predicted vital exhaustion, and resignation tendency partially mediated this relationship. However, core self-evaluation did not predict hair cortisol concentration. These findings suggest that core self-evaluation plays a crucial role in preventing vital exhaustion among teachers. A positive core self-evaluation seems beneficial for teachers' primary and secondary appraisal and an essential resource for the long-term prevention of self-reported vital exhaustion.

Association between workaholism, vital exhaustion, and hair cortisol concentrations among teachers: A longitudinal study testing the moderation effect of neuroticism.

Introduction: Workaholism in teachers is characterized by the willingness to work until exhausted and may be associated with various adverse health outcomes as well as high economic costs. The present study examines the association between workaholism, vital exhaustion (VE), and hair cortisol concentration (HCC) as indicators of chronic stress. In addition, this study explores the moderating role of the personality trait neuroticism on the relationship between workaholism and chronic stress indicators, i.e., VE and HCC. Methods: Forty-two Swiss teachers (28 females; M age = 39.66, SD = 11.99) completed questionnaires assessing VE (Maastricht Vital Exhaustion Questionnaire), workaholism (Measure of Coping Capacity Questionnaire), and neuroticism (Big-Five Inventory). Together with VE, HCC was assessed twice, with a one year lag. Results: Both workaholism and neuroticism were positively associated with VE at both time points but not with HCC. Moderation analyses revealed a positive relationship between workaholism and VE in teachers with high neuroticism, while no such association was observed in teachers with low neuroticism. No associations were found between self-reports and HCC. Discussion: These findings emphasize the importance of considering individual characteristics when investigating VE. Further research is necessary to investigate the applicability of HCC as a biomarker of chronic stress in the context of work.

Resilience as a Protective Factor in Basic Military Training, a Longitudinal Study of the Swiss Armed Forces.

For recruits, basic military training (BMT) can be experienced as a stressful episode in which relevant protective factors such as resilience might be essential for successful completion of the training. The present study examined whether resilience would act as a protective factor during BMT in the Swiss Armed Forces. To this end, we conducted a cross-sectional and longitudinal study of resilience and psychological burden. At the beginning of the BMT and at week 11, 525 male recruits (mean age: 20.3 years) completed a series of questionnaires covering demographic information and assessing resilience, perceived stress and mental distress. In parallel, their superiors rated recruits' military performance in week 13. Dropout rates were also registered. Cross-sectionally and longitudinally, higher resilience scores predicted lower scores for perceived stress, mental distress, and better military performance. Higher self-rated resilience was moderately associated with military performance, as rated by recruits' superiors. Resilience scores, perceived stress and mental distress did not differ between those recruits continuing their BMT and dropouts. In support of our assumptions, resilience acted as a protective factor during Swiss Armed Forces BMT.

The effects of acute work stress and appraisal on psychobiological stress responses in a group office environment.

BACKGROUND: The high prevalence of office stress and its detrimental health consequences are of concern to individuals, employers and society at large. Laboratory studies investigating office stress have mostly relied on data from participants that were tested individually on abstract tasks. In this study, we examined the effect of psychosocial office stress and work interruptions on the psychobiological stress response in a realistic but controlled group office environment. We also explored the role of cognitive stress appraisal as an underlying mechanism mediating the relationship between work stressors and the stress response. METHODS AND MATERIALS: Ninety participants (44 female; mean age 23.11 ± 3.80) were randomly assigned to either a control condition or one of two experimental conditions in which they were exposed to psychosocial stress with or without prior work interruptions in a realistic multi-participant laboratory setting. To induce psychosocial stress, we adapted the Trier Social Stress Test for Groups to an office environment. Throughout the experiment, we continuously monitored heart rate and heart rate variability. Participants repeatedly reported on their current mood, calmness, wakefulness and perceived stress and gave saliva samples to assess changes in salivary cortisol and salivary alpha-amylase. Additionally, cognitive appraisal of the psychosocial stress test was evaluated. RESULTS: Our analyses revealed significant group differences for most outcomes during or immediately after the stress test (i.e., mood, calmness, perceived stress, salivary cortisol, heart rate, heart rate variability) and during recovery (i.e., salivary cortisol and heart rate). Interestingly, the condition that experienced work interruptions showed a higher increase of cortisol levels but appraised the stress test as less threatening than individuals that experienced only psychosocial stress. Exploratory mediation analyses revealed a blunted response in subjective measures of stress, which was partially explained by the differences in threat appraisal. DISCUSSION: The results showed that experimentally induced work stress led to significant responses of subjective measures of stress, the hypothalamic-pituitary-adrenal axis and the autonomic nervous system. However, there appears to be a discrepancy between the psychological and biological responses to preceding work interruptions. Appraising psychosocial stress as less threatening but still as challenging could be an adaptive way of coping and reflect a state of engagement and eustress.

Ambulatory Assessment of Psychological and Physiological Stress on Workdays and Free Days Among Teachers. A Preliminary Study.

OBJECTIVE: Teachers are affected by high levels of job stress, leading to one of the highest rates of burnout. The purpose of our pilot study was to investigate the diurnal course of teachers' psychological and physiological stress responses [cortisol levels, alpha-amylase, heart rate (HR), and heart rate variability (HRV)]. Another aim of the project was to test the applicability of ambulatory assessment methods in daily teaching situations. METHODS: In a non-clinical sample of eight primary school teachers (mean age = 43, SD = 15.22, 6 females) in Switzerland, continuous biopsychological data on two workdays and a free day were assessed. The teachers' HRs and HRV were measured continuously using an ambulatory ECG. Additionally, eight saliva samples were collected from the teachers repeatedly throughout the day to determine the diurnal course of salivary cortisol and alpha-amylase (sAA). Perceived stress and anger ratings were assessed simultaneously. RESULTS: As hypothesized, the teachers' morning cortisol levels, perceived stress, and anger levels were significantly higher, and their overall HRV was significantly lower on workdays than on a free day. Conversely, sAA levels and HRs showed no significant differences between working and free days. Salivary markers exhibited the expected diurnal course, with decreasing cortisol and increasing sAA levels over the course of the day, while self-rated stress reached the maximum at midday during working days. CONCLUSION: The results of the present explorative study show that physiological and psychological parameters differ within working and free days for teachers. A comparison between working and free days resulted in differences in morning cortisol levels, HRV as well as stress and anger levels. The ambulatory assessment method was found to be applicable in daily teaching situations.

Psychosocial Stress Before a Nap Increases Sleep Latency and Decreases Early Slow-Wave Activity.

Sleep disturbances are an important risk factor for stress-related diseases such as burnout or depression. In particular, slow-wave activity (SWA) during sleep might be eminently relevant for optimal maintenance of mental health and cognitive functioning. In spite of the clinical importance and the pertinence of stress-related processes in everyday life, the physiological mechanisms of the association between stress, sleep, and cognition are not well-understood. In the present study, we carefully mapped the time course of the influence of a psychosocial stressor on sleep architecture and sleep-related oscillations during a midday nap. We induced stress using a psychosocial laboratory stressor, the Montreal Imaging Stress Task, vs. a neutral control task. Afterward, participants were allowed to take a 90-min nap (n = 20) or stayed awake (n = 19) and cortisol was measured via saliva samples. We hypothesized that stress would decrease sleep efficiency and SWA in a time-dependent manner, with impairing effects on cognitive functioning. Psychosocial stress resulted in increased cortisol levels, which were elevated throughout the study interval. In the nap group, psychosocial stress increased sleep latency, but had only minor effects on sleep architecture. Still, SWA in the first 30 min of sleep was significantly reduced, whereas alpha activity was enhanced. These effects vanished after approximately 30 min. No impairing effect on cognitive functioning occurred. Our results show that psychosocial stress before sleep has an impact on sleep latency and early SWA during sleep. In contrast to our hypothesis, the effects were rather small and short-lasting. Importantly, cognitive functioning was maintained. We conclude that the effects of psychosocial stress before a nap are possibly better compensated than previously believed.

Cardiovascular and psychological responses to voluntary recall of trauma in posttraumatic stress disorder.

Voluntary recall of trauma is a key element in exposure-based psychotherapies and can trigger spontaneous dissociative responses such as flashbacks, depersonalisation, and derealisation. In order to examine the associations between cardiovascular and psychological responses to voluntary recollection of trauma, individuals with PTSD recalled a traumatic memory. Heart rate and heart rate variability were recorded continuously and the episodes when different forms of dissociation were experienced during the recall were identified. A significant increase in parasympathetic activity was found during trauma recall, with greater parasympathetic dominance being indicative of greater state depersonalisation/derealisation. Whereas overall decreases in heart rate during trauma recall were associated with increased fear and perceived threat, flashbacks were accompanied by short-term increases in heart rate. These findings demonstrate different types of cardiovascular responses associated with different psychological experiences during trauma recall. Future research directions were discussed.

El recuerdo voluntario del trauma es un elemento clave en las psicoterapias basadas en la exposición y puede gatillar respuestas disociativas espontáneas como flashbacks, despersonalización y desrealización. Con el fin de examinar las asociaciones entre las respuestas cardiovascular y psicológica al recuerdo voluntario del trauma, individuos con TEPT evocaron una memoria traumática. Se midió en forma continua su frecuencia cardiaca y la variabilidad de la misma y se identificó los episodios en que experimentaron diferentes formas de disociación durante la evocación. Se encontró un incremento significativo en la actividad parasimpática durante el recuerdo del trauma, siendo una mayor dominancia parasimpática indicadora de un mayor estado de despersonalización/desrealización. Mientras que una disminución general en la frecuencia cardiaca durante el recuerdo del trauma se asoció a un incremento del miedo y percepción de amenaza, los flashbacks estaban acompañados de incrementos breves de la frecuencia cardiaca. Estos hallazgos demuestran que diferentes tipos de respuesta cardiovascular se asocian a diferentes experiencias psicológicas durante el recuerdo del trauma. Se discutieron futuras direcciones para la investigación.

Long-term stability of diurnal salivary cortisol and alpha-amylase secretion patterns.

This study aimed to investigate long-term stability and variability of diurnal cortisol and alpha-amylase patterns. Diurnal cortisol and alpha-amylase secretion patterns were assessed on a single workday with three waves of measurement across a total time period of 24months in 189 participants. Separate hierarchical linear models were analyzed, with and without a number of potential predictor variables (age, BMI, smoking, chronic stress, stress reactivity). While low long-term stability was found in diurnal cortisol, the stability of diurnal alpha-amylase was moderate across the time period of 24months. Several predictor variables had a positive impact on diurnal cortisol and alpha-amylase secretion patterns averaged across waves. Our findings underpin the notion that long-term stability is not necessarily warranted in longitudinal studies. It is important to choose an appropriate study design when attempting to disentangle clinically and biologically relevant changes from naturally occurring variations in diurnal cortisol and alpha-amylase.

Physical fitness level affects perception of chronic stress in military trainees.

This study investigated whether physical fitness affects the perception of chronic stress in military trainees while controlling for established factors influencing stress perception. The sample consisted of 273 men (20.23 ± 1.12 years, 73.56 ± 10.52 kg, 1.78 ± 0.06 m). Physical fitness was measured by progressive endurance run (maximum oxygen uptake; VO2 max), standing long jump, seated shot put, trunk muscle strength, and one leg standing test. Perceived stress was measured using the Perceived Stress Questionnaire in Weeks 1 and 11 of basic military training (BMT). VO2 max and four influencing variables (perceived stress in Week 1, neuroticism, transformational leadership style, and education level) explained 44.44% of the variance of the increase in perceived stress during 10 weeks of BMT (R2  = 0.444, F = 23.334, p < .001). The explained variance of VO2 max was 4.14% (R2  = 0.041), with a Cohen's f2 effect size of 0.045 (assigned as a small effect by Cohen, ). The results indicate a moderating influence of good aerobic fitness on the varied level of perceived stress. We conclude that it is advisable to provide conscripts with a specific endurance training program prior to BMT for stress prevention reasons.

Aerobic Fitness Level Affects Cardiovascular and Salivary Alpha Amylase Responses to Acute Psychosocial Stress.

BACKGROUND: Good physical fitness seems to help the individual to buffer the potential harmful impact of psychosocial stress on somatic and mental health. The aim of the present study is to investigate the role of physical fitness levels on the autonomic nervous system (ANS; i.e. heart rate and salivary alpha amylase) responses to acute psychosocial stress, while controlling for established factors influencing individual stress reactions. METHODS: The Trier Social Stress Test for Groups (TSST-G) was executed with 302 male recruits during their first week of Swiss Army basic training. Heart rate was measured continuously, and salivary alpha amylase was measured twice, before and after the stress intervention. In the same week, all volunteers participated in a physical fitness test and they responded to questionnaires on lifestyle factors and personal traits. A multiple linear regression analysis was conducted to determine ANS responses to acute psychosocial stress from physical fitness test performances, controlling for personal traits, behavioural factors, and socioeconomic data. RESULTS: Multiple linear regression revealed three variables predicting 15 % of the variance in heart rate response (area under the individual heart rate response curve during TSST-G) and four variables predicting 12 % of the variance in salivary alpha amylase response (salivary alpha amylase level immediately after the TSST-G) to acute psychosocial stress. A strong performance at the progressive endurance run (high maximal oxygen consumption) was a significant predictor of ANS response in both models: low area under the heart rate response curve during TSST-G as well as low salivary alpha amylase level after TSST-G. Further, high muscle power, non-smoking, high extraversion, and low agreeableness were predictors of a favourable ANS response in either one of the two dependent variables. CONCLUSIONS: Good physical fitness, especially good aerobic endurance capacity, is an important protective factor against health-threatening reactions to acute psychosocial stress.

Salivary Alpha-Amylase Correlates with Subjective Heat Pain Perception.

OBJECTIVE: Self-reports of pain are important for an adequate therapy. This is a problem with patients and infants who are restricted in providing an accurate verbal estimation of their pain. Reliable, real-time, economical, and non-invasive physiological correlates might contribute to a more comprehensive description of pain. Salivary alpha-amylase constitutes one candidate biomarker, which reflects predominantly sympathetic nervous system alterations under stressful conditions and can be measured non-invasively. The current study investigated the effects of acute heat pain on salivary alpha-amylase activity. METHODS: Heat pain tolerance was measured on the non-dominant forearm. Participants completed visual analog scales on pain intensity and unpleasantness. Saliva samples were collected directly after pain induction. SUBJECTS: Twenty-seven healthy volunteers were recruited for this study. RESULTS: While salivary alpha-amylase levels correlated positively with intensity and unpleasantness ratings in response to acute heat pain stimuli, there was no corresponding association with pain tolerance. CONCLUSIONS: Salivary alpha-amylase is suggested to be an indirect physiologic correlate of subjective heat pain perception. Future studies should address the role of salivary alpha-amylase depending on the origin of pain, the concerned tissue, and other pain assessment methods.

Alpha-Amylase Activity in Blood Increases after Pharmacological, But Not Psychological, Activation of the Adrenergic System.

BACKGROUND & AIM: Alpha-amylase in both blood and saliva has been used as a diagnostic parameter. While studies examining alpha-amylase activity in saliva have shown that it is sensitive to physiological and psychological challenge of the adrenergic system, no challenge studies have attempted to elucidate the role of the adrenergic system in alpha-amylase activity in blood. We set out to examine the impact of psychological and pharmacological challenge on alpha-amylase in blood in two separate studies. METHODS: In study 1, healthy subjects were examined in a placebo-controlled, double-blind paradigm using yohimbine, an alpha2-adrenergic antagonist. In study 2, subjects were examined in a standardized rest-controlled psychosocial stress protocol. Alpha-amylase activity in blood was repeatedly measured in both studies. RESULTS: Results of study 1 showed that alpha-amylase in blood is subject to stronger increases after injection of yohimbine compared to placebo. In study 2, results showed that there was no significant effect of psychological stress compared to rest. CONCLUSIONS: Alpha-amylase in blood increases after pharmacological activation of the adrenergic pathways suggesting that sympathetic receptors are responsible for these changes. Psychological stress, however, does not seem to have an impact on alpha-amylase in blood. Our findings provide insight into the mechanisms underlying activity changes in alpha-amylase in blood in healthy individuals.

Blunted endocrine and cardiovascular reactivity in young healthy women reporting a history of childhood adversity.

BACKGROUND: Chronic or prolonged stress exposure in childhood can alter structural and functional brain development, leading to mental and physical illness and alterations of psychobiological stress systems in adulthood. Recently, attenuation in stress reactivity of the hypothalamic-pituitary-adrenal (HPA) axis and cardiovascular system have been related to the number of adverse childhood experiences (ACEs). We set out to investigate the association of ACE duration and age of ACE occurrence on stress reactivity. METHODS: 104 women in the age range 18-25 years (mean=21.7) free of mental and physical illness underwent psychosocial stress testing with the Montreal Imaging Stress Task (MIST). Free saliva cortisol and heart rate were assessed repeatedly before and after the MIST. RESULTS: Number of ACEs was associated with attenuated cortisol and heart rate responses to stress in a dose-response relationship. Whereas overall duration of ACEs was significantly associated with an attenuated cortisol response, the specific age of first ACE occurrence did not contribute further to the dampened stress response. CONCLUSIONS: ACEs are associated with blunted endocrine and cardiovascular stress reactivity in young and healthy women. Adverse life events in childhood, particularly if they occur repeatedly and chronically, show a strong association with alterations in stress reactivity in adulthood, potentially predisposing for later mental or physical disorders.