Big five traits and interpersonal goals during stressors as predictors of hair cortisol

Hair cortisol as a marker of stress in mild traumatic brain injury: a challenging measure

Cortisol is released through activation of the hypothalamic-pituitary-adrenal axis by physiological and psychological stressors, such as mild traumatic brain injury (mTBI). This hormone is accumulated in hair over longer periods of time, reflecting both acute and chronic forms of stress, allowing for retrospective analyses within certain timeframes. The main objectives of this study were to analyze pre- and post-injury hair cortisol concentrations, and to explore possible associations with personality and recovery after mTBI. Hair samples of 61 mTBI patients were collected at 4-6 weeks post-injury and divided into pre- (1 cm) and post-injury (1 cm) segments. For comparison, hair samples of 24 age, sex and education matched healthy controls (HC) were collected and divided into similar segments. Cortisol was quantified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). At two weeks post-injury, post-traumatic symptoms (PTS), emotional distress (anxiety/depression), and the personality trait neuroticism were measured. At six months post-injury, PTS and functional recovery (Glasgow Outcome Scale Extended) were determined. A significant increase in hair cortisol concentration from pre- to post-injury was found for both mTBI patients and HC, likely due to washout effects, with similar concentrations in both groups. Neither hair cortisol, nor the interaction with neuroticism, were associated with long-term PTS or functional recovery. Additionally, no differences in hair cortisol were observed between patients with a higher and lower risk of developing persistent PTS based on a modified Post-Concussion Symptoms Rule (PoCS Rule) including demographics, acute symptoms, pre-injury mental health and head CT. Altogether, our findings do not support the current use of hair cortisol as a potential marker of stress in mTBI.

The effects of single testosterone administration and stress induction on steroid hormone levels in hair

Hair steroid analysis is increasingly recognized for its ability to capture cumulative hormone secretion, thought to reflect an individual's response to long-term environmental conditions. Despite its growing use, the influence of single, isolated events on hair steroid concentrations remains underexplored. Our study therefore examined the effects of a single-dose transdermal testosterone administration (150 mg) and acute laboratory stress induction on hair testosterone and cortisol levels in a randomized, between-subject, placebo-controlled, and double-blind design. Liquid chromatography-tandem mass spectrometry analysis revealed a significant increase in hair testosterone levels seven weeks post-testosterone administration, underscoring the efficacy of hair analysis in detecting single-use hormone intake. Moreover, we observed a significant elevation in hair cortisol levels seven weeks post-exposure to the laboratory somatic stressor (Cold pressor test), highlighting the efficacy of hair analysis in capturing experimentally induced hormonal responses. The exploration of contextual factors revealed that individuals in committed relationships exhibited lower levels of both hair cortisol and testosterone compared to those who were single or in uncommitted relationships. Our study provides new insights into the sensitivity of hair analysis for detecting hormonal changes following single-dose hormone administration and experimentally induced short-term stress events. The exploratory findings emphasize the importance of individual contextual factors in influencing hair hormone concentrations and lay the groundwork for further investigation into the dynamics of cumulative hair hormone measurements.

Characterizing Stress Processes by Linking Big Five Personality States, Traits, and Day-to-Day Stressors

The accumulation of day-to-day stressors can impact mental and physical health. How people respond to stressful events is a key mechanism responsible for the effects of stress, and individual differences in stress responses can either perpetuate or prevent negative consequences. Most research on daily stress processes has focused on affective responses to stressors, but stress responses can involve more than just affect (e.g., behavior, cognitions). Additionally, most research has studied the role of neuroticism in shaping those responses, but many other individual differences are associated with stress. In this study, we more broadly characterized daily stress processes by expanding the nomological networks of stress responses to include Big Five personality states. We also linked those stress responses to all Big Five traits, as well as individual differences in stress variety, severity, and controllability. We studied a sample of participants (N = 1,090) who reported on stressful events, their appraisal of events in terms of severity and controllability, and their Big Five personality states daily for 8-10 days (N = 8,870 observations). Multi-level structural equation models were used to separate how characteristics of the perceived stressful situation and characteristics of the person play into daily stress processes. Results showed that (1) all Big Five personality states shift in response to perceived stress, (2) all Big Five personality traits relate to average levels of perceived stress variety, severity, and controllability, (3) individual differences in personality and average perceived stress variety and perceived severity relate to the strength of personality state responses to daily stress, albeit in a more limited fashion. Our results point to new pathways by which stressors affect people in everyday life and begin to clarify processes that may explain individual differences in risk or resilience to the harmful effects of stress.

Associations between the Big Five personality traits, testosterone, and cortisol in adolescent male athletes

Testosterone (T) has been conceptualized as a biomarker of individual differences, yet T associations with the Big Five personality traits are inconsistent. Athletes provide a suitable model for evaluation here, as T co-expresses traits related to male-to-male competition and fitness with cortisol (C) playing a moderating role. This study investigated associations between the Big Five traits, T, and C in adolescent male athletes. One hundred and twenty male ice hockey players (aged 14-19 years) were assessed for blood total (T, C) and free (FT, FC) hormones, body-size dimensions (i.e., body mass, height, body mass index [BMI]), the Big Five personality traits (i.e., extraversion, neuroticism, agreeableness, conscientiousness, openness), and trait anxiety. Correlational and regression (with age and BMI as covariates) analyses identified a positive effect of FT on extraversion, but a negative FT effect on neuroticism and anxiety (p < 0.05). Significant FT × FC interactions emerged for extraversion and agreeableness. Slope testing revealed that FT had a positive effect on extraversion at the FC mean and +1 SD, and a negative effect on agreeableness with FC at +1 SD. In conclusion, adolescent male athletes with a higher serum FT concentration tended to express higher extraversion, but lower neuroticism and anxiety. The FT association with extraversion was moderated by FC concentration, as was agreeableness. Therefore, high-FT athletes presented a behavioural disposition that favours dominance and resiliency, with some dependencies on FC availability. Since all association effect sizes were weak, replicate studies on larger adolescent samples are needed.

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.

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.

Pre-pandemic Psychobiological Features Predict Impact of COVID-19 Confinement on Loneliness

The coronavirus disease 2019 (COVID-19) pandemic led to various government-imposed limitations on social interaction and strict home confinement. Such involuntary social-distancing policies can exacerbate feelings of loneliness and alter emotional well-being. Dysregulation of the hypothalamic-pituitary-adrenocortical (HPA) axis is a potential mechanism for loneliness' deleterious health effects. In this study, we explored whether pre-pandemic diurnal cortisol output (AUC G ), a measure of HPA axis function, may predict the propensity to changes in loneliness during long-term COVID-19 home confinement and if extraversion would moderate this relationship. This association has been explored by analysing the impact of COVID-19 pandemic and strict home confinement on social and emotional loneliness in 45 Spanish young adults. Diurnal cortisol levels were measured from five saliva samples obtained across a day just before the pandemic, and data about participants' perceived loneliness, empathic state, extraversion, and prospective volunteering were obtained both before and during the confinement. Participants' social and family loneliness increased during long-term strict home confinement, while prospective volunteering tendencies and extraversion decreased. Importantly, after adjusting for relevant confounders, moderation analyses revealed that in young adults with high pre-pandemic extraversion, a higher AUC G predicted a larger increase in social loneliness during confinement, while in individuals with low extraversion, AUC G was negatively related to change in loneliness. Our findings highlight the utility of pre-pandemic diurnal cortisol output in predicting the social impact of COVID-19 home confinement, presenting this hormone as a potential biomarker for a priori identification of at-risk groups during public health crises.