Alterations of postawakening cortisol parameters during a prolonged stress period: Results of a prospective controlled study

Daily life stress and the cortisol awakening response over a 13-months stress period - Findings from the LawSTRESS project

The LawSTRESS project is a controlled prospective-longitudinal study on psychological, endocrine, central nervous and genetic predictors of responses to long-lasting academic stress in a homogenous cohort. In this first project report, we focused on the association between daily life stress and the cortisol awakening response (CAR). The CAR, a distinct cortisol rise in the first 30-45 min after morning awakening, is a well-established marker of cortisol regulation in psychoneuroendocrinology. Law students from Bavarian universities (total n = 452) have been studied over a 13-months period at six sampling points starting 12 months prior exam. The stress group (SG) consisted of students experiencing a long-lasting and significant stress period, namely the preparation for the first state examination for law students. Law students assigned to the control group (CG) were studied over an equally long period without particular and sustained stress exposure. To investigate stress related alterations in the CAR, we examined a subsample of the LawSTRESS project consisting of 204 students with 97 participants from the SG (69.1% female, mean age = 22.84 ± 1.82) and 107 from the CG (78.5% female, mean age = 20.95 ± 1.93). At each sampling point, saliva samples for cortisol assessment were collected immediately upon awakening and 30 as well as 45 min later. Perceived stress in daily life was measured by repeated ambulatory assessments (about 100 queries over six sampling points). The time course of perceived stress levels in the two groups differed significantly, with the SG showing an increase in perceived stress until the exam and a decrease thereafter. Stress levels in the CG were relatively stable. The CAR was not significantly different between groups at baseline. However, a blunted CAR in the SG compared to the baseline measure and to the CG developed over the measurement timepoints and reached significance during the exam. Remarkably, this effect was neither associated with the increase in perceived stress nor with anxiety and depression symptoms, test anxiety and chronic stress at baseline. The present study successfully assessed multidimensional stress trajectories over 13 months and it documented the significant burden, law students preparing for the first state examination are exposed to. This period was related to a blunted CAR with presumed physiological consequences (e.g., on energy metabolism and immune function). Mean psychological stress levels as well as the CAR returned to baseline levels after the exam, suggesting a fast recovery in the majority of the participants.

Examination stress in academic students: a multimodal, real-time, real-life investigation of reported stress, social contact, blood pressure, and cortisol

ObjectiveAcademic examinations are a frequent and significant source of student stress, but multimodal, psychophysiological studies are still missing. Participants & methods: Psychological and physiological variables were assessed on 154 undergraduate students in daily life using e-diaries resp. blood pressure devices at the beginning of the semester, and again before an examination. Results: Multilevel analysis revealed lower calmness, more negative valence, higher task-related stress, higher demands, lower perceived control, lower frequency of social contact, and a higher desire to be alone during the examination period (all p values < .0001), as well as lower ambulatory systolic blood pressure (p = .004), heightened cortisol at awakening (p = .021), and a smaller increase in cortisol (p = .012). Conclusions: Our study revealed empirical evidence that examination periods are not only associated with indicators of dysphoria, stress, and social withdrawal but also by altered physiological processes, which might reflect anticipatory stress and withdrawal effects.

Motivation and learning methods of anatomy: Associations with mental well-being

Appropriate anatomy education for speech and language therapists is a crucial part of preparation for clinical practice. While much research has been conducted regarding the anatomical education of medical students, there is a paucity of evidence for speech and language therapy students. This study assessed the methods employed by a cohort of first-year speech and language therapy students to learn anatomy, their perceptions of the clinical importance of anatomy and motivation to learn anatomy (using a modified version of the motivation strategies for learning questionnaire) and how this related to potential barriers to motivation such as mental well-being (using the Warwick-Edinburgh Mental Well-Being Scale [WEMWBS]). Analysis revealed that 92% of students agreed or strongly agreed that a sound knowledge of anatomy is important for clinical practice, 74% agreed or strongly agreed that listening at lectures was how they primarily learned anatomy, and 91% of students agreed or strongly agreed that they worried a great deal about tests. The latter statement was negatively correlated with a number of statements on the WEMWBS. Overall, the data revealed that first-year speech and language therapy students place importance on anatomy and its role in their future clinical practice, that they have different preferences for learning anatomy compared to medical students, and also have significant anxiety surrounding anatomy examinations. Multiple significant correlations between responses to the motivation and mental well-being questionnaires suggest that there is a significant relationship between first-year student motivation to learn anatomy and well-being.

The Cortisol Awakening Response Mediates the Relationship Between Acculturative Stress and Self-Reported Health in Mexican Americans

BACKGROUND

The assessment of acculturative stress as synonymous with acculturation level overlooks the dynamic, interactive, and developmental nature of the acculturation process. An individual's unique perception and response to a range of stressors at each stage of the dynamic process of acculturation may be associated with stress-induced alterations in important biological response systems that mediate health outcomes. Evidence suggests the cortisol awakening response (CAR) is a promising pre-clinical biomarker of stress exposure that may link acculturative stress to self-reported health in Mexican Americans.

PURPOSE

The aim of the current study was to examine whether alterations in the CAR mediate the relationship between acculturative stress and self-reported health in Mexican Americans.

METHODS

Salivary cortisol samples were collected at awakening, 30, 45, and 60 min thereafter, on two consecutive weekdays from a sample of adult Mexican Americans. Acculturative stress and self-reported health were assessed. Data were aggregated and analyzed (n = 89) using a mixed effects regression model and path analysis.

RESULTS

Poorer self-reported health was associated with attenuated CAR profiles (primarily due to a diminished post-awakening rise in cortisol) predicted by both moderate and high levels of exposure to acculturative stress. Stress-induced alterations in the CAR mediated the relationship between exposure to acculturative stressors and self-reported health.

CONCLUSIONS

Findings demonstrate that different levels of acculturative stress are associated with distinct CAR profiles and suggest the CAR is one possible biological pathway through which exposure to culturally unique stressors may be linked to health disparities.

Mother-Toddler Cortisol Synchrony Moderates Risk of Early Internalizing Symptoms

Cortisol synchrony is the degree to which mother-toddler cortisol levels are mutually regulated within a dyad. Synchrony's impact on toddler development is not well understood, so this study investigated how synchronous cortisol levels (reactivity and total concentration) in mother-toddler dyads moderates the association between risk factors (i.e., maternal worry, toddler inhibition) and early internalizing symptoms. Seventy mothers and their 2-year-old toddlers provided interpretable saliva samples. Behavioral observations were made to assess the toddler's temperament at age 2, and mothers reported on their toddler's internalizing symptoms when toddlers were 2- and 3-years-old. Results suggest that mother-toddler synchrony in total cortisol concentration moderates the relation between risk factors and internalizing symptoms. Specifically, toddler inhibition and maternal worry were less associated with concurrent toddler internalizing symptoms when dyads demonstrated greater cortisol synchrony in total concentration. Further, synchrony in total cortisol levels marginally moderated the association between toddler inhibition and future internalizing symptoms, such that inhibited toddlers were less likely to demonstrate internalizing symptoms at age 3 when dyads demonstrated more cortisol synchrony. This suggests that cortisol synchrony may serve as an advantageous context that reduces the risk of developing of internalizing symptoms and augments the field's understanding of the implications of shared physiological responses within mother-toddler dyads.

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.

Effect of prolonged stress on the adrenal hormones of individuals with irritable bowel syndrome

Background

The purpose of this study was to investigate the effect of prolonged stress on the salivary adrenal hormones (cortisol, dehydroepiandrosterone [DHEA], DHEA-sulfate [DHEA-S]) of individuals with irritable bowel syndrome (IBS).

Methods

The participants were female college students, including 10 with IBS and 16 without IBS (control group), who were scheduled for a 2-week teaching practice at a kindergarten. Participants were asked to collect saliva for determining adrenal hormones immediately and 30 min after awakening and before sleep, 2 weeks before the practice, the first week of the practice, the second week of the practice, and a few days after the practice.

Results

Regarding cortisol/DHEA ratio, significantly increased levels were found during the first week of the practice, and a significant interaction between group and time was found; the ratio at 30 min after awakening in the IBS group was higher than that in the control group. For the other adrenal hormone indexes, no significant differences due to the presence of IBS were found.

Conclusions

Individuals with IBS showed an elevated cortisol/DHEA ratio after awakening compared with individuals without IBS, and the elevated ratio peaked under the prolonged stress. The present study suggests that the cortisol effect is dominant in individuals with IBS under prolonged stress.

Somatic symptoms evoked by exam stress in university students: the role of alexithymia, neuroticism, anxiety and depression

OBJECTIVE

The etiology of somatization is incompletely understood, but could be elucidated by models of psychosocial stress. Academic exam stress has effectively been applied as a naturalistic stress model, however its effect on somatization symptoms according to ICD-10 and DSM-IV criteria has not been reported so far. Baseline associations between somatization and personality traits, such as alexithymia, have been studied exhaustively. Nevertheless, it is largely unknown if personality traits have an explanatory value for stress induced somatization.

METHODS

This longitudinal, quasi-experimental study assessed the effects of university exams on somatization - and the reversal of effects after an exam-free period. Repeated-observations were obtained within 150 students, measuring symptom intensity before, during and after an exam period, according to the Screening for Somatoform Symptoms 7-day (SOMS-7d). Additionally, self-reports on health status were used to differentiate between medically explained and medically unexplained symptoms. Alexithymia, neuroticism, trait-anxiety and baseline depression were surveyed using the Toronto-Alexithymia Scale (TAS-20), the Big-Five Personality Interview (NEO-FFI), the State Trait Anxiety Inventory (STAI) and Beck's Depression Inventory (BDI-II). These traits were competitively tested for their ability to explain somatization increases under exam stress.

RESULTS

Somatization significantly increased across a wide range of symptoms under exam stress, while health reports pointed towards a reduction in acute infections and injuries. Neuroticism, alexithymia, trait anxiety and depression explained variance in somatization at baseline, but only neuroticism was associated with symptom increases under exam stress.

CONCLUSION

Exam stress is an effective psychosocial stress model inducing somatization. A comprehensive quantitative description of bodily symptoms under exam stress is supplied. The results do not support the stress-alexithymia hypothesis, but favor neuroticism as a personality trait of importance for somatization.

Chronic stress exposure decreases the cortisol awakening response in healthy young men

Academic examination is a major stressor for students in China. Investigation of stress-sensitive endocrine responses to major examination stress serves as a good model of naturalistic chronic psychological stress in an otherwise healthy population. The cortisol awakening response (CAR) is an endocrine marker of the hypothalamic-pituitary-adrenocortical (HPA) axis in response to stress. However, it remains unknown how chronic examination stress impacts the CAR in a young healthy population To exclude the influence of sex effects on hormone level, the CAR and psychological stress responses were assessed on two consecutive workdays in 42 male participants during their preparations for the Chinese National Postgraduate Entrance Exam (NPEE) and 21 non-exam, age-matched male comparisons. On each day, four saliva samples were collected immediately after awakening, 15 minutes, 30 minutes and 60 minutes after awakening. The waking level (S1), the increase within 30 minutes after awakening (R30), the area under the curve with respect to ground (AUCg), and the area under the curve with respect to increase (AUCi) were used to quantify the CAR. Psychological stress and anxiety were assessed by the Perceived Stress Scale and the Spielberger State-Trait Anxiety Inventory, respectively. Male participants in the exam group had greater perceived stress and anxiety scores relatibe to the non-exam group. Both R30 and AUCi in the exam group were significantly lower than the comparison group and this effect was most pronounced for participants with high levels of perceived stress in the exam group. Perceived stress and anxiety levels were negatively correlated with both R30 and AUCi. Chronic examination stress can lead to the decrease of CAR in healthy young men, possibly due to reduced HPA axis activity under long-term sustained stress.

Effects of prolonged stress on salivary cortisol and dehydroepiandrosterone: a study of a two-week teaching practice

This study investigated variations in salivary levels of cortisol and dehydroepiandrosterone (DHEA) in a prolonged stressful situation (a two-week teaching practice). Thirty-three women for whom a two-week teaching practice at a kindergarten was scheduled were asked to collect saliva samples at awakening, 30 min after awakening, and bedtime at four time points: two weeks before the practice, the first week of the practice, the second week of the practice, and a few days after the practice. In addition, they completed questionnaires for assessing perceived stress and subjective moods on each day. A linear mixed model indicated that cortisol levels significantly increased during the first and second week of the practice compared with those before and after the practice period, and that DHEA levels significantly decreased after the practice period compared with those at the other time points. Further, cortisol awakening response after the practice period significantly reduced compared with that at the other time points. Scores of perceived stress and negative moods were also higher during the practice period. This study showed that prolonged stress affected cortisol and DHEA secretion during as well as after the stress period.

Intraindividual stability of hair cortisol concentrations

The analysis of cortisol in human hair constitutes a promising method for the retrospective assessment of cumulative cortisol secretion over extended periods of time. An implicit assumption underlying the use of this method is that in the absence of major life changes hair cortisol concentrations show a high level of intraindividual stability, i.e. single hair cortisol assessments exhibit considerable trait-specificity and are only to a smaller extent influenced by state-dependent factors. Here, we present data from two independent studies examining patterns of intraindividual stability in hair cortisol levels. In study I, 45 participants were examined at two sampling points carried out one year apart from each other. In study II, 64 individuals provided data at three sampling points which occurred at two-month intervals. In both studies, at each time point hair was sampled and relevant psychosocial and hair-related variables were assessed. Results of both studies consistently revealed strong test-retest associations for repeated hair cortisol measurements ('r's between 0.68 and 0.79, 'p's <0.0001). Findings of structural equation modelling applied to data of study II showed that single hair cortisol assessments comprise a strong trait component, explaining between 59 and 82% of variance, and are only to a lesser extent influenced by state-related factors. Only inconsistent evidence for covariation of changes in hair cortisol concentrations and simultaneous changes in perceived stress or other relevant variables was seen across the two studies. The current findings suggest a considerable degree of intraindividual stability in hair cortisol levels which highlights the utility of this method for obtaining trait estimates of long-term cortisol secretion in psychoneuroendocrinological research.