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

Blunted anticipatory stress responses on competition day in team sports athletes compared to individual sports athletes

Knowledge of anticipatory stress responses before sports competitions is limited, thus this study examined the relationship between anticipatory stress in terms of salivary cortisol secretion in athletes on the morning of a competition and a comparison baseline day. Thirty-seven athletes collected three saliva samples over a 45-min period post-awakening (0, 30 and 45 min). Anticipatory stress was expressed as Area Under the Curve compared to ground (AUCg; total cortisol secretion). There was no significant difference in AUCg between baseline and competition days. However, a mixed two-factor ANOVA with day and sport type (individual vs. team) revealed a significant main effect of sport type (p < 0.01) and a significant interaction (p = 0.001). Individual athletes demonstrated increased AUCg on competition day compared to baseline, while team athletes demonstrated decreased AUCg on competition day compared to baseline. This blunting response was also observed when analysing the raw cortisol secretion levels upon awakening. These findings suggest there may be substantive differences in anticipatory stress between individual and team sport athletes.

Anticipated stress predicts the cortisol awakening response: An intensive longitudinal pilot study

The cortisol awakening response (CAR) has been hypothesized to prepare the body for anticipated demands of the upcoming day. This pilot study investigates the influence of anticipated stress on the upcoming day on the CAR, using an intensive longitudinal design with ecological momentary assessments. Over a 30-day period, three healthy participants collected saliva samples each morning at three time points after awakening to measure cortisol levels and completed a questionnaire each evening on the anticipated stress for the following day. Additionally, they wore a smart headband to objectively determine the time point of awakening. There was high variability in the CAR magnitude within participants over time. A multi-level model was estimated to investigate the influence of anticipated stress on the CAR. Results indicated that anticipated stress is predictive of the CAR on the following morning, with higher anticipated stress being associated with increased cortisol levels at the post-awakening time points. These findings underscore the role of stress anticipation in modulating the CAR and highlight the importance of considering within-person variation and temporally lagged effects in biopsychological research.

The inconsistency of p-curve: Testing its reliability using the power pose and HPA debates

Recent works have called into question whether p-curve can reliably assess the presence of "evidential value" within a set of studies. To examine an as-yet unexplored issue, we examined the method used to identify p-values for inclusion in a p-curve analysis. We developed iterated p-curve analysis (IPA), which calculates and p-curves every permutation for a set of reported p-values, and applied it to the data reported in several published p-curve analyses. Specifically, we investigated two phenomena for which p-curves have been used to evaluate the presence of evidential value: the power pose and the hypothalamic-pituitary-adrenal (HPA) reactivity debates. The iterated p-curve analyses revealed that the p-curve method fails to provide reliable estimates or reproducible conclusions. We conclude that p-curve should not be used to make conclusions regarding the presence or absence of evidence for a specific phenomenon.

The cortisol awakening response is blunted in healthy women early postpartum

INTRODUCTION

The dynamic capacity of the hypothalamic-pituitary-adrenal (HPA) axis supports healthy adaptions to stress and play a key role in maintaining mental health. Perinatal adaptations in the HPA-axis dynamics in terms of the Cortisol Awakening Response (CAR), may be involved in dysregulation of perinatal mental health. We aimed to determine if CAR and absolute evening cortisol early postpartum differed from non-perinatal women and evaluate the association between the CAR and maternal mental well-being.

METHODS

The CAR was computed as the area under the curve with respect to increase from baseline from serial home-sampling of saliva across 0-60 minutes from awakening. We evaluated differences in CAR and absolute evening cortisol between postpartum women (N=50, mean postpartum days: 38, SD: ±11) and non-perinatal women (N=91) in a multiple linear regression model. We also evaluated the association between CAR and maternal mental well-being in a multiple linear regression model.

RESULTS

We found that healthy postpartum women had a blunted CAR (p<0.001) corresponding to 84% reduction and 80% lower absolute evening cortisol (p<0.001) relative to non-perinatal healthy women. In the postpartum group, there was a trend-level association between lower CAR and higher scores on the WHO Well-Being Index (WHO-5) (p=0.048) and lower Edinburgh Postnatal Depression Scale (EPDS) scores (p=0.04).

CONCLUSION

Our data emphasize the unique hormonal landscape during the postpartum period in terms of blunted CAR and lower absolute evening cortisol in healthy women early postpartum compared to non-perinatal. Our findings show a potential association between a reduced CAR and improved mental well-being during early motherhood, which suggests that reduced CAR might reflect healthy adjustment to early motherhood.

Interplay of Adolescents' and Parents' Mindsets of Socioeconomic Status on Adolescents' Stress-Related Outcomes

The reciprocity and variation of values and beliefs are dynamic features of the parent-child relationship. Parents and adolescents may hold congruent or incongruent views regarding the malleability of socioeconomic status (mindset of SES), potentially influencing adolescents' psychological and physiological stress outcomes, as reflected in stress perceptions and the hypothalamic-pituitary-adrenal (HPA) axis functioning. The current study investigated how patterns of parent-adolescent congruence and incongruence in mindset of SES were associated with adolescents' perceived stress and diurnal cortisol patterns four months later. A total of 253 adolescents (Mage = 12.60, 46.2% girls) and their parents (Mage = 40.09 years, 59.5% mothers) participated in this study. Polynomial regression analyses and response surface analyses showed that adolescents perceived lower levels of stress when they themselves or their parents reported a stronger growth mindset of SES. Additionally, adolescents with a stronger growth mindset of SES also exhibited a steeper diurnal cortisol slope. Moreover, parents' mindset significantly interacted with adolescents' mindset to influence adolescents' diurnal cortisol patterns such that when adolescents hold weaker growth mindset of SES, those with higher parental growth mindsets had significantly higher cortisol awakening response and steeper diurnal cortisol slope. Furthermore, adolescents who showed incongruence with their parents but had averagely stronger growth mindsets of SES reported a significantly steeper diurnal cortisol slope than those who had averagely weaker growth mindsets with their parents. The findings point to the beneficial impacts of the growth mindset of SES on stress-related outcomes among adolescents, as well as the significance of considering both parents' and adolescents' mindsets when exploring these associations.

A distinct immune cytokine profile is associated with morning cortisol and repeated stress

OBJECTIVE

The objective of this study was to investigate possible immune cytokine trends throughout a week-long surgical simulation mass-casualty training session in order to determine the effects of stress inoculation on the immune system.

METHODS

Thirty-seven military medical students participated in a hyper-realistic surgical simulation training event conducted at Strategic Operations site in San Diego, California. Salivary samples were collected every morning of the stress training exercise for 4 consecutive days. Cortisol, along with a panel of 42 immune cytokines, was measured using multiplex enzyme-linked immunosorbent assays from Eve Technologies. The determined concentrations were averaged and plotted on a scatter plot, and then points were fit to a second-order polynomial trendline of best fit to measure.

RESULTS

The cytokines epidermal growth factor, growth-related oncogene-α, interleukin (IL)-1α, and platelet-derived growth factor-AA followed a noted pattern of cortisol decrease throughout the week. In addition, cytokines IL-27, granulocyte colony stimulating factor, IL-10, and IL-13 demonstrated a late peak, followed by a return to baseline at the conclusion of training. Finally, the cytokine monocyte chemoattractant protein-1 displayed a decline throughout the week followed by an increase on the last day of stress training.

CONCLUSIONS

Altogether, these results help to identify important biomarkers that may help to improve long-term stress adaptation and prevent post-traumatic stress disorder following exposure to repeated stress.

[Depression in the field of tension of gender roles]

BACKGROUND

The distribution of depression and suicidal ideation by gender reveals a gender paradox: women are at least twice as likely to be diagnosed with depressive disorders but have a lower suicide rate than men. In contrast, the suicide rate of men is at least three times higher than women, while the prevalence of depressive disorders is only half as high. Although these differences have long been known the reasons for this paradox are still not fully understood.

AIM OF THE ARTICLE AND METHOD

The aim of this narrative review article is to discuss possible explanatory models regarding gender differences in depressive disorders. Aspects related to stress processing and traumatization are considered as well as sociological and biological factors. This article summarizes information that was considered particularly relevant in the interdisciplinary dialogue regarding possible explanatory factors for gender differences in depressive disorders.

RESULTS

The summarized studies indicate that women and men differ in certain aspects of stress processing and trauma exposure but men do not have a lower risk of disease as a result. On the contrary, the frequency of depressive disorders in men seems to be underestimated due to an atypical symptom manifestation.

DISCUSSION

The implementation of knowledge about gender-specific vulnerability in the training of physicians and psychotherapists, the systematic assessment of gender beyond binary classifications as well as further diversity domains in research and healthcare as well as gender-sensitive and diversity-sensitive prevention strategies could contribute to the resolution of the gender paradox.

Early childhood multiple or persistent regulatory problems and diurnal salivary cortisol in young adulthood

BACKGROUND

Early childhood multiple or persistent regulatory problems (RPs; crying, sleeping, or feeding problems) have been associated with a risk of behavioural problems in young adulthood. It has been suggested that this may be due to the possible influence of early RPs on the functioning of the hypothalamic-pituitary-adrenal (HPA) axis. However, associations between early RPs and HPA-axis activity in young adulthood remain unexplored. Thus, the aim of the current study was to investigate whether early childhood multiple or persistent RPs are associated with diurnal salivary cortisol in young adulthood.

METHODS

At the ages of 5, 20 and 56 months, RPs of 308 children from the Arvo Ylppö Longitudinal Study were assessed via standardized parental interviews and neurological assessments. Multiple RPs were defined as two or three RPs at the age of 5 months and persistent RPs as at least one RP at 5, 20 and 56 months. At the mean age of 25.4 years (SD= 0.6), the participants donated saliva samples for cortisol at awakening, 15 and 30 min thereafter, 10:30 am, at noon, 5:30 pm, and at bedtime during one day. We used mixed model regressions, and generalized linear models for testing the associations, controlling for important covariates.

RESULTS

Of the 308 children, 61 (19.8%) had multiple or persistent RPs in early childhood: 38 had multiple, and 27 had persistent RPs. Persistent RPs were associated with significantly higher cortisol peak and output in the waking period, and cortisol awakening response. On the other hand, multiple RPs were not associated with salivary cortisol.

CONCLUSION

Children displaying persistent RPs throughout early childhood show, over two decades later, increased HPA axis activity in response to awakening stress. This may be one physiological mechanism linking early childhood RPs to adulthood behavioural outcomes.

Reliability of diurnal salivary cortisol metrics: A meta-analysis and investigation in two independent samples

Stress-induced dysregulation of diurnal cortisol is a cornerstone of stress-disease theories; however, observed associations between cortisol, stress, and health have been inconsistent. The reliability of diurnal cortisol features may contribute to these equivocal findings. Our meta-analysis (5 diurnal features from 11 studies; total participant n = 3307) and investigation (15 diurnal cortisol features) in 2 independent studies (St. Louis Personality and Aging Network [SPAN] Study, n = 147, ages 61-73; Minnesota Longitudinal Study of Risk and Adaptation [MLSRA] Study, n = 90, age 37) revealed large variability in the day-to-day test-retest reliability of diurnal features derived from salivary cortisol data (i.e., ICC = 0.00-0.75). Collectively, these data indicate that some commonly used diurnal cortisol features have poor reliability that is insufficient for individual differences research (e.g., cortisol awakening response) while others (e.g., area under the curve with respect to ground) have fair-to-good reliability that could support reliable identification of associations in well-powered studies.

Effects of cranial electrotherapy stimulation on improving depressive symptoms in people with stress: A randomized, double-blind controlled study

BACKGROUND

Cranial electrotherapy stimulation (CES) is a form of neurostimulation that delivers alternating microcurrent via electrodes on the head. We investigated the effectiveness of CES in reducing stress.

METHODS

Participants who experienced subjective stress combined with subclinical depression or insomnia were recruited based on interviews and questionnaires. The subjects were randomly assigned to the active CES or sham groups and asked to use the device for 30 min twice a day for three weeks. Psychological rating scales, quantitative electroencephalography (QEEG), and serial salivary cortisol levels were measured before and after the intervention.

RESULTS

Sixty-two participants (58 females, mean age = 47.3 ± 8.2 years) completed the trial. After intervention, the depression scores improved significantly to a nearly normal level (Beck depression inventory-II, 31.3 ± 11.6 to 10.8 ± 7.2, p < 0.001) in the CES group, which were greater improvement compared to the sham group (p = 0.020). There were significant group-by-visit interactions in absolute delta power in the temporal area (p = 0.033), and theta (p = 0.038), beta (p = 0.048), and high beta power (p = 0.048) in the parietal area. CES led to a flattening of the cortisol slope (p = 0.011) and an increase in bedtime cortisol (p = 0.036) compared to the sham group.

LIMITATIONS

Bias may have been introduced during the process because device use and sample collection were self-conducted by participants at home.

CONCLUSIONS

CES can alleviate depressive symptoms and stress response, showing a potential as an adjunctive therapy for stress.

Short-term cortisol adaption to discrimination and Mexican-origin adolescents' mental and sleep health

Discrimination experiences are a salient contributor to the health disparities facing Latina/x/o youth. The biopsychosocial model of minority health posits that discrimination influences health through wear and tear on the biological stress responses, including the hypothalamic-pituitary-adrenal (HPA) axis, which is a primary stress response system in the body. Emerging evidence suggests that discrimination alters the secretion of cortisol, the end product of the HPA axis, yet, whether the daily processes between discrimination and diurnal cortisol response influence mental and sleep health remains unanswered. This study integrated daily diary and post-diary survey data to examine whether daily diurnal cortisol responses to discrimination influence adolescents' mental (depressive symptoms, anxiety) and sleep (sleep quality, duration) health in a sample of Mexican-origin youth (N = 282; M age = 17.10; 55% female). Results showed that adolescents who experienced more discrimination across the four-day diary period exhibited steeper diurnal cortisol slopes and lower evening cortisol; however, such physiological responses tended to be associated with poorer adolescents' mental and sleep health. The current study underscores the potential adaptation cost associated with short-term cortisol adaptation in the face of discrimination.

Dimensions of child maltreatment and longitudinal diurnal cortisol patterns: The roles of resilience and child sex

Informed by the dimensional approach to adversity, this study disaggregated child maltreatment effects to examine how abuse versus neglect influenced cortisol at the baseline assessment and longitudinal changes in diurnal cortisol among a sample of Chinese children and adolescents (N = 312; aged 9-13 years; M age = 10.80, SD = 0.84; 67% boys). The moderating roles of resilience and sex differences in these associations were also explored. Results revealed distinct effects of abuse versus neglect on diurnal cortisol in girls, but not boys, which varied by the time scale of assessment and type of cortisol measure. Specifically, abuse was associated with girls' longitudinal changes in awakening cortisol, cortisol awakening response, and diurnal cortisol slope over one year, whereas neglect was associated with girls' awakening cortisol and cortisol awakening response at the baseline assessment. Further, resilience moderated the effects of abuse on girls' baseline awakening cortisol and longitudinal changes in diurnal cortisol slope, suggesting both the potential benefits and costs of resilience. Findings support the application of the dimensional approach to research on stress physiology and deepen our understanding of individual differences in the associations between child maltreatment and diurnal cortisol.

Parent-Child Separation and Diurnal Cortisol Rhythms Among Left-Behind Adolescents: The Moderating Role of Sex

Prior research examining parent-child separation and the hypothalamic-pituitary-adrenal (HPA) axis functioning has primarily focused on separation due to parental divorce or loss or forced migration. Less clear is the impact of parental economic migration on adolescents' HPA axis functioning. The present study fills this gap by examining diurnal cortisol patterns among left-behind adolescents who experienced separation from their migrant parents. Participants were 293 Chinese adolescents (33.4% girls, 66.21% left-behind adolescents; M_age = 10.80 years old, SD = 0.82 years). Two-level multilevel modeling was conducted to examine the associations between parent-child separation experiences and diurnal cortisol patterns. Although no significant differences were found between left-behind adolescents and their non-left-behind peers, results revealed that left-behind adolescents who experienced parent-child separation at earlier ages had more blunted diurnal cortisol slopes (usually signaling poorer mental and physical health), compared to their counterparts who experienced separation at older ages. Left-behind adolescent girls who had more adverse separation experiences exhibited smaller waking cortisol and blunted diurnal slopes; these findings were not observed among left-behind adolescent boys. Observing the association between timing of parent-child separation and adolescents' diurnal cortisol and the moderating effects of child sex, this study contributes uniquely to the developmental science of left-behind adolescents' physiological health.

Lifetime discrimination, habitual and daily everyday discrimination, and diurnal cortisol among older African Americans adults

Experiences of discrimination can be major life events or daily chronic hassles that occur in various social contexts (e.g., housing, education, employment) and have been found to predict adverse health outcomes, including dysregulation of the Hypothalamic-Pituitary-Adrenal (HPA) axis. Previous work on daily cortisol dynamics has generally revealed an association between discrimination and flatter cortisol slopes, particularly among racial minorities. However, most of the existing studies have focused on youth and young adults, with little work among older adults. The current study aimed to investigate the relationship between three measures of discrimination (lifetime discrimination, habitual everyday discrimination, and daily everyday discrimination) and diurnal cortisol secretion in a sample of 203 older African Americans. Study results indicated that individuals reporting higher levels of lifetime discrimination experienced morning hypocortisolism and flatter diurnal cortisol slopes. Exploratory analyses also showed that prior daily everyday discrimination was significantly associated with blunted cortisol awakening response (CAR) the next day. Our findings underline the role of discrimination in modulating daily cortisol dynamics among older African American adults and advance knowledge on how social stressors influence healthy aging.

Dietary Intake, Serum Hormone Concentrations, Amenorrhea and Bone Mineral Density of Physique Athletes and Active Gym Enthusiasts

As the diet, hormones, amenorrhea, and bone mineral density (BMD) of physique athletes (PA) and gym enthusiasts (GE) are little-explored, we studied those in 69 females (50 PA, 19 GE) and 20 males (11 PA, 9 GE). Energy availability (EA, kcal·kgFFM−1·d−1 in DXA) in female and male PA was ~41.3 and ~37.2, and in GE ~39.4 and ~35.3, respectively. Low EA (LEA) was found in 10% and 26% of female PA and GE, respectively, and in 11% of male GE. In PA, daily protein intake (g/kg body mass) was ~2.9−3.0, whereas carbohydrate and fat intakes were ~3.6−4.3 and ~0.8−1.0, respectively. PA had higher protein and carbohydrate and lower fat intakes than GE (p < 0.05). Estradiol, testosterone, IGF-1, insulin, leptin, TSH, T4, T3, cortisol, or BMD did not differ between PA and GE. Serum IGF-1 and leptin were explained 6% and 7%, respectively, by EA. In non-users of hormonal contraceptives, amenorrhea was found only in PA (27%) and was associated with lower fat percentage, but not EA, BMD, or hormones. In conclusion, off-season dietary intakes, hormone levels, and BMD meet the recommendations in most of the PA and GE. Maintaining too-low body fat during the off-season may predispose to menstrual disturbances.

The association of self-esteem variability with diurnal cortisol patterns in a sample of adult workers

This study explored the relationships between self-esteem level and self-esteem variability at work with parameters of diurnal cortisol rhythm, using intensive longitudinal data collected during two consecutive working days from N = 166 workers. Participants self-reported measures of sex, height, weight, self-esteem, neuroticism, and negative events at T0. Then, they answered a single item of self-esteem 4 times per day. Self-esteem variability was assessed by means of the relative variability index approach proposed by Mestdagh et al. (2018). Further, participants collected salivary samples at specific time points for analysis of diurnal cortisol patterns. Self-esteem average levels and a specific form of self-esteem variability were associated with diurnal cortisol parameters. In particular, results showed a relationship between low self-esteem and blunted cortisol awakening response, specifically when low self-esteem levels were stable over time. Moreover, self-esteem variability predicted a lower diurnal cortisol decline and a smaller magnitude of overall cortisol production. Present findings highlight the neuroendocrine correlates of self-esteem level and variation at work, suggesting potential pathways by which short-term variability in self-esteem states may impact hypothalamic-pituitary-adrenal axis functioning and long-term workers' health and well-being.

Evaluation and update of the expert consensus guidelines for the assessment of the cortisol awakening response (CAR)

The cortisol awakening response (CAR) is frequently assessed in psychobiological (stress) research. Obtaining reliable CAR data, however, requires careful attention to methodological detail. To promote best practice, expert consensus guidelines on the assessment of the CAR were published (Stalder et al., 2016, PNEC). However, it is unclear whether these highly cited guidelines have resulted in actual methodological improvements. To explore this, the PNEC editorial board invited the present authors to conduct a critical evaluation and update of current CAR methodology, which is reported here. (i) A quantitative evaluation of methodological quality of CAR research published in PNEC before and after the guidelines (2013-2015 vs. 2018-2020) was conducted. Disappointingly, results reveal little improvement in the implementation of central recommendations (especially objective time verification) in recent research. (ii) To enable an update of guidelines, evidence on recent developments in CAR assessment is reviewed, which mostly confirms the accuracy of the majority of the original guidelines. Moreover, recent technological advances, particularly regarding methods for the verification of awakening and sampling times, have emerged and may help to reduce costs in future research. (iii) To aid researchers and increase accessibility, an updated and streamlined version of the CAR consensus guidelines is presented. (iv) Finally, the response of the PNEC editorial board to the present results is described: potential authors of future CAR research to be published in PNEC will be required to submit a methodological checklist (based on the current guidelines) alongside their article. This will increase transparency and enable reviewers to readily assess the quality of the respective CAR data. Combined, it is hoped that these steps will assist researchers and reviewers in assuring higher quality CAR assessments in future research, thus yielding more reliable and reproducible results and helping to further advance this field of study.

The relationship between cortisol awakening response and trait resilience in two patient cohorts and one population-based cohort

OBJECTIVES

We examined (1) the proportion of cortisol awakening non-responders, (2) the association between cortisol awakening response (CAR) and trait resilience, and (3) the association between CAR increase and trait resilience in two patient cohorts (depression and myocardial infarction [CVD]) and one population-based cohort.

METHODS

Eight hundred and eighty study participants delivered CAR scores (response and increase) based on three self-collected saliva samples and a trait resilience score. Descriptive data of CAR non-responders were reported and calculated. Associations between CAR response/increase and trait resilience, sociodemographic and compliance variables were evaluated using multiple logistic and multiple linear regression analyses stratified by cohort.

RESULTS

The proportion of CAR non-responders was high in all cohorts (57% depression cohort, 53.4% CVD cohort, 51.6% control cohort). In the depression cohort age was associated with CAR response and increase. In the CVD cohort salivary collection on a weekday was associated with CAR response and awakening time with CAR increase. In the control cohort age was associated with CAR response and sex with CAR increase.

CONCLUSIONS

We observed many CAR non-responders and significant associations between CAR response and CAR increase with single sociodemographic and compliance variables. We did not find significant relationships between CAR response or increase and trait resilience.

Adverse childhood experiences and diurnal cortisol patterns in older people in England

Adverse childhood experiences (ACE) are associated with HPA axis dysregulation at younger ages, but there is scarcity of evidence for this association at older ages. To add to our knowledge of the lifetime impact of ACE on HPA axis function, we examined whether ACE were associated with diurnal cortisol patterns in a national sample of 587 participants (356 women) aged 55-79 years from the English Longitudinal Study of Ageing (ELSA). We conducted descriptive analyses and estimated sex-specific robust regression models of the associations between the 8-item summary ACE score and four measurements of salivary cortisol over a 24-h cycle (upon waking, 30 min later, at 7 pm, and at bedtime) as well as the cortisol awakening response (CAR) and the diurnal cortisol slope. Our models were adjusted for age, then for childhood socioeconomic position and finally for adult socioeconomic position. In men, we found significant differences that were independent of covariates, with more ACE being associated with lower salivary cortisol levels on waking, a greater CAR, and a flatter diurnal cortisol slope. In women, we observed a graded association between ACE and increased 7 pm salivary cortisol levels. Our findings indicate that childhood adversity is related to HPA axis in older people, especially men. The chronological distance (on average >50 years) between ACE and salivary cortisol levels suggests the existence of a lifelong association between childhood adversity and HPA axis and neuroendocrine function. Notwithstanding sex differences, based on our findings we suggest that HPA axis dysregulation could be a pathway that mediates the association between ACE and chronic disease later in life.

Cortisol levels in rural Latina breast cancer survivors participating in a peer-delivered cognitive-behavioral stress management intervention: The Nuevo Amanecer-II RCT

Background

Compared to their White counterparts, Latina breast cancer survivors have poorer survival rates and health-related quality of life, and higher rates of depression and anxiety which may be a result of chronic stress. Chronic stress impacts the hypothalamic-pituitary-adrenal (HPA) axis, resulting in cortisol dysregulation which may be associated with breast cancer survival. However, cortisol levels and cortisol profiles of Latina breast cancer survivors are poorly characterized due to their underrepresentation in biomedical research.

Objective

The objective of this study was to describe cortisol levels and patterns of cortisol secretions in rural Latina breast cancer survivors participating in an RCT study of Nuevo Amanecer-II, an evidence-based peer-delivered cognitive behavioral stress management intervention.

Methods

Participant-centered recruitment and collection strategies were used to obtain biospecimens for cortisol analysis. Nine saliva samples (3/day for 3 days) and a hair sample were obtained at baseline and 6-months (3-months post-intervention). We describe cortisol levels and profiles, explore correlations of biomarkers with self-report measures of stress and psychological distress, and compare women who received the intervention with a delayed intervention group on biomarkers of stress. Mean hair cortisol concentration (HCC) was used to assess chronic stress. Based on daily measures of cortisol (awakening, 30 min post-awakening, and bedtime), we calculated three summary measures of the dynamic nature of the cortisol awakening response (CAR): 1) the CAR slope, 2) whether CAR demonstrates a percent change ≥40, and 3) total daily cortisol output (AUCg). Linear and log-binomial regression, accounting for multiple samples per participant, were used to compare cortisol measures at 6-month follow-up by treatment arm.

Results

Participants (n = 103) were from two rural California communities; 76 provided at least one saliva sample at baseline and follow-up and were included in the analysis. At baseline, mean age was 57 years, mean years since diagnosis was 2 years, 76% had a high school education or less, and 34% reported financial hardship. The overall median CAR slope was 0.10, and median cortisol AUCg (in thousands) was 11.34 (range = 0.93, 36.66). Mean hair cortisol concentration was 1751.6 pg/mg (SD = 1148.6). Forty-two percent of samples had a ≥40% change in CAR. We found no statistically significant correlations between the cortisol measures and self-reported measures of stress and psychological distress. At follow-up, no differences were seen in HCC (mean difference between intervention and control: −0.11, 95% CI -0.48, 0.25), CAR slope (0.001, 95% CI -0.005, 0.008), cortisol AUCg (−0.15, 95% CI -0.42, 0.13), or ≥40% change in CAR (prevalence ratio 0.87, 95% CI 0.42, 1.77) between treatment arms.

Conclusion

Our findings of flattened cortisol profiles among more than half of the sample suggest potential HPA-axis dysregulation among rural Spanish-speaking Latina breast cancer survivors that merits further study due to its implications for long-term survival.

Trial registration

http://www.ClinicalTrials.gov identifier NCT02931552.

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Latina breast cancer survivors displayed flattened cortisol profiles.

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Hair cortisol levels, a measure of chronic stress, were found to be elevated.

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Stress biomarkers and self-report measures did not substantially correlate.

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Latina breast cancer survivors are vulnerable to the repercussion of HPA-axis dysregulation.

Open and reproducible science practices in psychoneuroendocrinology: Opportunities to foster scientific progress

This perspective article was written by invitation of the editors in chief as a summary and extension of the symposium entitled Psychoneuroendocrine Research in the Era of the Replication Crisis which was held at the virtual meeting of the International Society of Psychoneuroendocrinology 2021. It highlights the opportunities presented by the application of open and reproducible scientific practices in psychoneuroendocrinology (PNE), an interdisciplinary field at the intersection of psychology, endocrinology, immunology, neurology, and psychiatry. It conveys an introduction to the topics preregistration, registered reports, quantifying the impact of equally-well justifiable analysis decisions, and open data and scripts, while emphasizing 'selfish' reasons to adopt such practices as individual researcher. Complementary to the call for adoption of open science practices, we highlight the need for methodological best practice guidelines in the field of PNE, which could further contribute to enhancing replicability of results. We propose concrete steps for future actions and provide links to additional resources for those interested in adopting open and reproducible science practices in future studies.

Physiological reactions to acute stressors and subjective stress during daily life: A systematic review on ecological momentary assessment (EMA) studies

OBJECTIVE

This review aims to provide an overview of ecological momentary assessment (EMA) studies analyzing stress reactivity during daily life in terms of direct and moderated influence of acute stress on physiological responses.

MATERIALS AND METHODS

A systematic literature search was performed on November 29, 2021 using Web of Science, MEDLINE and PsycINFO to identify prospective EMA studies targeting acute stressors or stress under naturalistic conditions, without restrictions of publication date or population. Study quality was assessed for multiple EMA-specific sources of bias.

RESULTS

Out of 4285 non-duplicate records, 107 publications involving 104 unique studies were included. The majority of studies assessed acute physiological stress responses primarily through salivary cortisol (n = 59) and cardiovascular outcomes (n = 32). Most studies performed at least three measurements per day (n = 59), and had a moderate risk of recall bias (n = 68) and confounding (n = 85). Fifty-four studies reported a compliance of ≥80%. Direct, non-moderated positive associations were observed between acute stress exposure and concurrent cortisol levels (44%, n = 11/25), systolic (44%, 8/18) and diastolic blood pressure (53%, 8/15) and heart rate (53%, 9/17). Several inter- and intra-individual moderators were identified, such as age, gender, health status, chronic stress, work-related resources, physical activity and stress coping indicators.

CONCLUSIONS

About half of the reviewed EMA studies demonstrated direct associations between everyday acute stress exposure and physiological responses, including increased cortisol levels, blood pressure and heart rate. Results further suggested various moderator variables that could help develop tailored prevention strategies and identify groups at higher risk for dysfunctional stress responses.

REGISTRATION

PROSPERO-Reg.-No.: PROSPERO 2020 CRD42020163178.

The Stressful Personality: A Meta-Analytical Review of the Relation Between Personality and Stress

The current study presented the first meta-analytic review on the associations between the Big Five personality traits and stress measured under different conceptualizations (stressor exposure, psychological and physiological stress responses) using a total of 1,575 effect sizes drawn from 298 samples. Overall, neuroticism was found to be positively related to stress, whereas extraversion, agreeableness, conscientiousness, and openness were negatively linked to stress. When stress assessed under different conceptualizations was tested, only neuroticism, agreeableness, and conscientiousness were related to stressor exposure. All of the Big Five personality traits were significantly associated with psychological stress perception, whereas the five personality traits showed weak to null associations with physiological stress response. Further moderation analyses suggested that the associations between personality traits and stress under different conceptualizations were also contingent upon different characteristics of stress, sample, study design, and measures. The results supported the important role of personality traits in individual differences in stress.

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.

Salivary Cortisol Awakening Response as a Predictor for Depression Severity in Adult Patients with a Major Depressive Episode Performing a Daily Exercise Program

INTRODUCTION

The hypothalamic-pituitary-adrenal axis function in depression has been the subject of considerable interest, and its function has been tested with a variety of methods. We investigated associations between saliva cortisol at awakening and the 24-h urine cortisol output, both measured at study baseline, with endpoint depression scores.

METHODS

Patients were admitted to a psychiatric inpatient ward with a major depressive episode and were started on fixed duloxetine treatment. They delivered saliva samples at awakening and 15, 30, and 60 min post-awakening and sampled urine for 24 h. Subsequently, they started a daily exercise program maintained for a 9-week period. Clinician-rated depression severity was blindly assessed with the Hamilton Depression Rating 6-item subscale (HAM-D6). The cortisol awakening response was quantified by the area under the curve with respect to the ground (AUCG) and with respect to the rise (AUCI) using saliva cortisol levels in the 1-h period after awakening. Analysis of expected associations between depression severity, AUCG, AUCI, exercise, and 24-h cortisol output was performed in a general linear model.

RESULTS

In all, 35 participants delivered saliva or 24-h urine samples. The mean age was 49.0 years (SD = 11.0) with 48.6% females with a mean baseline HAM-D6 score of 12.2 (SD = 2.3). In a statistical model investigating the association between HAM-D6 at week 9 as a dependent variable and AUCI, concurrent HAM-D6, gender, smoking, and exercise volume as covariates, we found a significant effect of AUCI, concurrent HAM-D6, and exercise. The following statistics were found: AUCI (regression coefficient 0.008; F value = 9.1; p = 0.007), concurrent HAM-D6 (regression coefficient 0.70; F value = 8.0; p = 0.01), and exercise (regression coefficient -0.005; F value = 5.7; p = 0.03). The model had an R2 of 0.43. The association between HAM-D6 endpoint scores and the AUCI showed that higher AUCI values predicted higher HAM-D6 endpoint values. The association between HAM-D6 endpoint scores and the exercise level showed that a high exercise level was associated with lower HAM-D6 endpoint values.

CONCLUSION

The results thus showed that high AUCI values predicted less improvement of depression and high exercise levels predicted more improvement of depression. These findings need to be confirmed in larger samples to test if more covariates can improve prediction of depression severity.

Cortisol awakening response in the airborne rescue service

BACKGROUND

Work-related stress may lead to mental and physical illnesses. Emergency physicians may be particularly vulnerable to developing such diseases due to their extreme emotional working environment.

AIMS

The purpose of the study was to analyse the hormonal stress burden of emergency physicians in the airborne rescue service to create an empirical basis for developing appropriate measures against chronic stress in the rescue service.

METHODS

Three salivary cortisol samples were collected after awakening in 15 min intervals-each on a flight rescue day, a clinic day and a free day-to calculate the extent of the hormonal stress load of the emergency physicians. A nested linear mixed-model analysis was used in 40 cases to investigate hormonal stress. Furthermore, professional years and gender were included in the calculations.

RESULTS

The mixed model showed neither a main effect for measurement time nor for day but a significant interaction effect (P = 0.002). The cortisol level rises strongly on the flight rescue and the clinic day, while on the free day it shows a moderate increase. Professional years and gender also proved to be statistically significant for the cortisol level of emergency physicians (P < 0.001).

CONCLUSIONS

The results show a significantly higher cortisol increase on working days compared with a free day, which indicates a stronger stress burden on working days of emergency physicians in the airborne rescue service. Future studies should examine the stress level of emergency physicians in more detail to prove whether the working conditions of emergency physicians need to be modified.

Mortality, Morbidity and Health-Related Outcomes in Informal Caregivers Compared to Non-Caregivers: A Systematic Review

A systematic overview of mental and physical disorders of informal caregivers based on population-based studies with good methodological quality is lacking. Therefore, our aim was to systematically summarize mortality, incidence, and prevalence estimates of chronic diseases in informal caregivers compared to non-caregivers. Following PRISMA recommendations, we searched major healthcare databases (CINAHL, MEDLINE and Web of Science) systematically for relevant studies published in the last 10 years (without language restrictions) (PROSPERO registration number: CRD42020200314). We included only observational cross-sectional and cohort studies with low risk of bias (risk scores 0–2 out of max 8) that reported the prevalence, incidence, odds ratio (OR), hazard ratio (HR), mean- or sum-scores for health-related outcomes in informal caregivers and non-caregivers. For a thorough methodological quality assessment, we used a validated checklist. The synthesis of the results was conducted by grouping outcomes. We included 22 studies, which came predominately from the USA and Europe. Informal caregivers had a significantly lower mortality than non-caregivers. Regarding chronic morbidity outcomes, the results from a large longitudinal German health-insurance evaluation showed increased and statistically significant incidences of severe stress, adjustment disorders, depression, diseases of the spine and pain conditions among informal caregivers compared to non-caregivers. In cross-sectional evaluations, informal caregiving seemed to be associated with a higher occurrence of depression and of anxiety (ranging from 4 to 51% and 2 to 38%, respectively), pain, hypertension, diabetes and reduced quality of life. Results from our systematic review suggest that informal caregiving may be associated with several mental and physical disorders. However, these results need to be interpreted with caution, as the cross-sectional studies cannot determine temporal relationships. The lower mortality rates compared to non-caregivers may be due to a healthy-carer bias in longitudinal observational studies; however, these and other potential benefits of informal caregiving deserve further attention by researchers.

Adrenal Gland Irradiation Causes Fatigue Accompanied by Reactive Changes in Cortisol Levels

BACKGROUND

Incidental radiotherapy (RT) to the adrenal gland may have systemic effects. This study aimed to investigate the effects of adrenal RT on fatigue.

METHODS

BALB/c mice were surgically explored to identify the left adrenal gland and delivered intra-operative RT. The swimming endurance test was used for endurance assessment to represent fatigue. Plasma levels of stress hormones and histopathological features were examined. Three patients with inevitable RT to the adrenal gland were enrolled for the preliminary study. Serum levels of cortisol, aldosterone, and adrenocorticotropic hormone (ACTH) were measured before and after RT. Fatigue score by using the fatigue severity scale and RT dosimetric parameters were collected.

RESULTS

In the experimental mouse model, adrenal RT decreased baseline cortisol from 274.6 ± 37.8 to 193.6 ± 29.4 ng/mL (p = 0.007) and swimming endurance time from 3.7 ± 0.3 to 1.7 ± 0.6 min (p = 0.02). In histopathological assessment, the irradiated adrenal glands showed RT injury features in the adrenal cortex. In the enrolled patients, baseline cortisol significantly declined after RT. There were no significant differences in the levels of morning cortisol, aldosterone, and ACTH before and after RT.

CONCLUSIONS

The RT dose distributed to the adrenal gland may correlate with unwanted adverse effects, including fatigue and adrenal hormone alterations.

Environmental Contributions to Anhedonia

Anhedonia is a core feature of psychopathological conditions that have recent exposure to stress and trauma as central to their etiology. Indeed, evolutionary accounts of depression suggest that decreased motivation to pursue reward may be an adaptive strategy in the face of social stress, in particular, as it may serve to defuse interpersonal conflict. Through a review of rodent models and research with humans, we show that exposure to stress, particularly when it is chronic, repeated, and/or involves themes of social rejection or defeat, is consistently associated with reduced hedonic capacity ("liking"), motivation to pursue reward ("wanting"), and ability to learn from reward ("reward learning"). Further, across rodent and human research, there is evidence that females show greater stress-induced blunting of reward processing than males. In humans, this sex difference emerges most strongly when examining individual differences in the stress response rather than group differences in stress exposure. We discuss the implications of these findings for understanding the etiology of, and sex differences in, stress-related psychopathology, including depression and addiction.

Relationship of Resilience Factors With Biopsychosocial Markers Using a Comprehensive Home Evaluation Kit for Depression and Suicide Risk: A Real-World Data Analysis

OBJECTIVES

Adverse childhood experiences (ACEs) are fundamental factors in developing depression with increased suicide risk. Resilience is considered an important protective factor that can prevent trauma survivors from developing depression. We developed a home evaluation kit for a comprehensive assessment of bio-psycho-social factors related to depression and suicide. This kit contained a psycho-social evaluation battery, named the Protective and Vulnerable factors battery questionnaire (PROVE) comprising depressive symptoms and suicide risk, as well as various depression-related psychosocial factors, such as ACE, resilience, mentalization capacity, and attachment, via online survey tools. Furthermore, salivary cortisol levels were used as biological indicators to assess the hypothalamus-pituitary-adrenal axis function.

METHODS

Real-world data analysis was made out of data collected from participants who visited CHEEU Counseling center or Gangnam Severance hospital for mental health check-ups. The participants were put into three mental state groups (green-normal, yellow-borderline, and red-risk) depending on the result of PROVE battery. The difference between psychosocial factors and salivary cortisol indicators by the group was identified by analysis of covariance with sex and age as covariates. Linear regression analysis was conducted to find a significant association of resilience score with other bio-psycho-social variables, such as ACE, attachment, mentalization, or post-awakening cortisol concentrations (area under the curve with respect to ground, AUCg). A partial correlation analysis was performed to evaluate the relationship of AUCg with psychosocial factors.

RESULTS

Depression-related psycho-social indicators were significantly different among groups. Insecure attachment and the mentalization problem are negatively influencing factors to resilience. Furthermore, the severity of depression in participants with ACE was also influenced by mentalization problems. AUCg was different according to the PROVE group, presence of ACE, or resilience level. In addition, AUCg showed a positive correlation with resilience score but negative correlations with depressive symptoms, ACE, mentalization problems, and anxiety or avoidance attachment.

CONCLUSION

This study suggests that there are some key factors negatively affecting resilience: insecure attachment and mentalization problems. In groups with ACE, a mentalization problem was suggested as a factor that can increase depressive symptoms. AUCg was associated with resilience as well as several other vulnerable factors of depression, showing its potential as a promising biomarker.

Caregiver subjective and physiological markers of stress and patient heart failure severity in family care dyads

Greater family caregiver exposure to uncontrolled patient symptoms is predictive of greater caregiver psychological and physiological stress in dementia and other chronic illnesses, but these phenomena have not been well-studied in heart failure (HF) - a disease with high symptom burden. The purpose of this study was to test the hypothesis that worse patient functional status (as reflected by increasing HF symptoms) would be associated with elevated psychological and physiological stress for the caregiver. This was a secondary analysis of data from 125 HF caregivers in the Caregiver Opportunities for Optimizing Lifestyle (COOL) study. Psychological stress was measured on four dimensions: care-related strain/burden (Oberst Caregiving Burden Scale), depression (Center for Epidemiological Studies Depression Scale), anxiety (State-Trait Anxiety Index), and general stress (Perceived Stress Scale). Physiological stress was measured by markers of HPA axis function (elevated cortisol awakening response [CAR]), endothelial dysfunction (increased PAI-1), and inflammation (increased IL-6, hsCRP). HF patient functional status was quantified by caregiver assessment of New York Heart Association (NYHA) Class. Generalized linear models were used to test associations between patient NYHA Class and stress (one model per indicator). NYHA Class (ordinal) was backwards difference coded in each model to examine caregiver stress in relation to increasing levels of HF severity. Caregivers were mostly female and in their mid-fifties, with a slight majority of the sample being African American and the patient's spouse. Overall, patient functional status was associated with greater caregiver psychological and physiological stress. In terms of psychological stress, higher NYHA Class was significantly associated with greater caregiver anxiety and general stress, but not with caregiver burden or depression. In terms of physiological stress, higher NYHA Class was associated with elevated markers in all models (elevated CAR and higher IL-6, hsCRP, and PAI-1). Across models, most associations between NYHA Class and stress were present at relatively early stages of functional limitation (i.e. Class II), while others emerged when functional limitations became more severe. To inform timing and mechanisms for much-needed caregiver interventions, research is needed to determine which aspects of HF symptomatology are most stressful for caregivers across the HF trajectory.

Induction of acute stress through an internet-delivered Trier Social Stress Test as assessed by photoplethysmography on a smartphone

Recent studies have demonstrated the feasibility of administering the Trier Social Stress Test (TSST) through the internet, with major implications for promoting inclusivity in research participation. However, online TSST studies to date are limited by a lack of control groups and the need for biological measures of stress reactivity that can be fully implemented online. Here, we test smartphone-based photoplethysmography as a measure of heart rate reactivity to an online variant of the TSST. Results demonstrate significant acceleration in heart rate and heightened self-reported stress and anxiety in the TSST condition relative to a placebo version of the TSST. The placebo condition led to a significant increase in self-reported stress and anxiety relative to baseline levels, but this increase was smaller in magnitude than that observed in the TSST condition. These findings highlight the potential for smartphone-based photoplethysmography in internet-delivered studies of cardiac reactivity and demonstrate that it is critical to utilize random assignment to a control or stressor condition when administering acute stress online.

Resilience and vulnerability factors influence the cortisol awakening response in individuals vulnerable to suicide

Suicide is a global health issue. Dysregulated hypothalamic-pituitary-adrenal (HPA) axis activity, as measured by cortisol levels, has been identified as one potential risk factor. Evidence is emerging to suggest that different psychological factors may be associated with increased resilience and vulnerability in this context. The current study investigated whether trait resilience, social support, socially prescribed perfectionism, trait worry and trait impulsivity influenced the cortisol awakening response (CAR) over a 7-day study in individuals vulnerable to suicide. 142 participants with a history of suicidal attempt or ideation (suicide vulnerability group; n = 95) and with no suicide risk history (control group; n = 47) were recruited. Participants completed baseline questionnaires before commencing a 7-day study where they provided cortisol samples immediately upon waking, at 15 min, 30 min and 45 min on 7 consecutive days. Higher worry, socially prescribed perfectionism and impulsivity, lower resilience and social support were found in the suicide vulnerability group compared to the control group. Lower levels of resilience, higher levels of socially prescribed perfectionism, worry and impulsivity were associated with significantly lower total CAR. Suicide group membership was also found to have an indirect effect on total CAR via trait worry. The current findings show for the first time, that these well-known psychological risk factors for suicide are associated with smaller total cortisol awakening responses. Researchers ought to elucidate the precise causal mechanisms linking these traits, CAR and suicide risk in order to develop interventions to help build resilience in vulnerable populations.

Associations between inertia of negative emotions and diurnal cortisol in a sample of college students

Emotional inertia refers to the extent to which emotional states are predictable over time and are resistant to change. High emotional inertia, characterized by emotional states that carry over from one moment to the next, has been linked with both psychological maladjustment and impaired emotion regulation abilities. However, little research has examined the psychobiological correlates of emotional inertia. As such, in this study, we examined the association between inertia of negative emotions with cortisol, the end product of the hypothalamic pituitary adrenal (HPA) axis, one of the body's primary stress response systems. Participants were 76 college students (24% male, Mage=18.53, SD=0.37), who completed five corresponding daily diaries and salivary samples to ascertain cortisol per day for 3 consecutive days. Hierarchical linear models indicated that greater inertia of negative emotion across the three days was associated with smaller cortisol awakening responses (CAR) and lower AUCg, even when controlling for average negative emotion and momentary stress perception. There were no associations with the diurnal cortisol slope. These findings shed light on the neurobiological mechanisms involved in emotion dynamics.

Moderation of the Stressor-Strain Process in Interns by Heart Rate Variability Measured with a Wearable and Smartphone App: a Within-Subject Design Using Continuous Monitoring

Background

The emergence of smartphones and wearable sensor technologies enables easy and unobtrusive monitoring of physiological and psychological data related to an individual’s resilience. Heart rate variability (HRV) is a promising biomarker for resilience based on between-subject population studies, but observational studies that apply a within-subject design and use wearable sensors in order to observe HRV in a naturalistic real-life context are needed.

Objective

This study aims to explore whether resting HRV and total sleep time (TST) are indicative and predictive of the within-day accumulation of the negative consequences of stress and mental exhaustion. The tested hypotheses are that demands are positively associated with stress and resting HRV buffers against this association, stress is positively associated with mental exhaustion and resting HRV buffers against this association, stress negatively impacts subsequent-night TST, and previous-evening mental exhaustion negatively impacts resting HRV, while previous-night TST buffers against this association.

Methods

In total, 26 interns used consumer-available wearables (Fitbit Charge 2 and Polar H7), a consumer-available smartphone app (Elite HRV), and an ecological momentary assessment smartphone app to collect resilience-related data on resting HRV, TST, and perceived demands, stress, and mental exhaustion on a daily basis for 15 weeks.

Results

Multiple linear regression analysis of within-subject standardized data collected on 2379 unique person-days showed that having a high resting HRV buffered against the positive association between demands and stress (hypothesis 1) and between stress and mental exhaustion (hypothesis 2). Stress did not affect TST (hypothesis 3). Finally, mental exhaustion negatively predicted resting HRV in the subsequent morning but TST did not buffer against this (hypothesis 4).

Conclusions

To our knowledge, this study provides first evidence that having a low within-subject resting HRV may be both indicative and predictive of the short-term accumulation of the negative effects of stress and mental exhaustion, potentially forming a negative feedback loop. If these findings can be replicated and expanded upon in future studies, they may contribute to the development of automated resilience interventions that monitor daily resting HRV and aim to provide users with an early warning signal when a negative feedback loop forms, to prevent the negative impact of stress on long-term health outcomes.

Curvilinear associations between family income in early childhood and the cortisol awakening response in adolescence

Previous evidence on cortisol output and socioeconomic status (SES) has been mixed, with studies finding that lower SES can be associated with higher or lower cortisol output, and null associations have also been reported. We hypothesized that these inconsistencies may be due to an underlying curvilinear, inverted-U pattern of association, such that low income is related to increased likelihood of both low and high cortisol output. We tested these curvilinear links among family income and cortisol indices in the Avon Longitudinal Study of Parents and Children (N = 803). Maternal reports of family income when the study children were 33 and 47 months of age were averaged to estimate early-childhood family income. Three cortisol indices were derived from samples collected in adolescence (15.5 years of age): the cortisol awakening response (CAR), area under the curve (AUC) cortisol, and the diurnal cortisol slope. As hypothesized, the CAR exhibited a curvilinear, inverted-U relation with childhood income, with low childhood income being associated with both the lowest and the highest CARs. These findings suggest that discrepancies in prior findings on low SES and the CAR may be due to curvilinear patterns of association. However, childhood income was not significantly associated with adolescent cortisol diurnal slope or AUC. Future work should clarify the factors that might predispose to high versus low CAR given equivalent low SES in childhood.

The differential calibration of the HPA axis as a function of trauma versus adversity: A systematic review and p-curve meta-analyses

Although there is an abundance of evidence linking the function of the hypothalamic-pituitary-adrenal (HPA) axis to adverse early-life experiences, the precise nature of the association remains unclear. Some evidence suggests early-life adversity leads to cortisol hyper-reactivity, while other evidence suggests adversity leads to cortisol hypo-reactivity. Here, we distinguish between trauma and adversity, and use p-curves to interrogate the conflicting literature. In Study 1, trauma was operationalized according to DSM-5 criteria; the p-curve analysis included 68 articles and revealed that the literature reporting associations between trauma and blunted cortisol reactivity contains evidential value. Study 2 examined the relationship between adversity and cortisol reactivity. Thirty articles were included in the analysis, and p-curve demonstrated that adversity is related to heightened cortisol reactivity. These results support an inverted U-shaped function relating severity of adversity and cortisol reactivity, and underscore the importance of distinguishing between "trauma" and "adversity".

Back to Basics: The Importance of Measurement Properties in Biological Psychiatry

Biological psychiatry is a major funding priority for organizations that fund mental health research (e.g., National Institutes of Health). Despite this, some have argued that the field has fallen short of its considerable promise to meaningfully impact the classification, diagnosis, and treatment of psychopathology. This may be attributable in part to a paucity of research about key measurement properties ("physiometrics") of biological variables as they are commonly used in biological psychiatry research. Specifically, study designs informed by physiometrics are more likely to be replicable, avoid poor measurement that results in misestimation, and maximize efficiency in terms of time, money, and the number of analyses conducted. This review describes five key physiometric principles (internal consistency, dimensionality, method-specific variance, temporal stability, and temporal specificity), illustrates how lack of understanding about these characteristics imposes meaningful limitations on research, and reviews examples of physiometric studies featuring a variety of popular biological variables to illustrate how this research can be done and substantive conclusions drawn about the variables of interest.

Daily provision of instrumental and emotional support to friends is associated with diurnal cortisol during adolescence

This study investigates how adolescents' daily prosocial behaviors to friends are related to diurnal cortisol using between- and within-subject analyses. Further, we examine whether role fulfillment (i.e., feeling like a good friend) moderates links between prosocial behaviors and cortisol. Ethnically diverse adolescents (N = 370; ages 11-18) reported whether they provided instrumental and emotional support to friends for 5 days, and provided four saliva samples/day for 4 days. On the daily level, providing emotional support predicted lower cortisol awakening response the next day, and providing instrumental assistance to friends was associated with a flatter cortisol slope the same day (a cardiovascular risk factor). Adolescents also provided more emotional support on days they had lower CAR and steeper cortisol slopes. On the average level, providing more instrumental support was associated with steeper cortisol slopes among adolescents who felt high levels of role fulfillment, but not among adolescents who felt low levels of role fulfillment. Providing instrumental support may be physiologically taxing from day to day but, across the long term, linked to lower cardiovascular risk for adolescents who experience helping as highly fulfilling.

Stress Markers for Mental States and Biotypes of Depression and Anxiety: A Scoping Review and Preliminary Illustrative Analysis

Depression and anxiety disrupt daily function and their effects can be long-lasting and devastating, yet there are no established physiological indicators that can be used to predict onset, diagnose, or target treatments. In this review, we conceptualize depression and anxiety as maladaptive responses to repetitive stress. We provide an overview of the role of chronic stress in depression and anxiety and a review of current knowledge on objective stress indicators of depression and anxiety. We focused on cortisol, heart rate variability and skin conductance that have been well studied in depression and anxiety and implicated in clinical emotional states. A targeted PubMed search was undertaken prioritizing meta-analyses that have linked depression and anxiety to cortisol, heart rate variability and skin conductance. Consistent findings include reduced heart rate variability across depression and anxiety, reduced tonic and phasic skin conductance in depression, and elevated cortisol at different times of day and across the day in depression. We then provide a brief overview of neural circuit disruptions that characterize particular types of depression and anxiety. We also include an illustrative analysis using predictive models to determine how stress markers contribute to specific subgroups of symptoms and how neural circuits add meaningfully to this prediction. For this, we implemented a tree-based multi-class classification model with physiological markers of heart rate variability as predictors and four symptom subtypes, including normative mood, as target variables. We achieved 40% accuracy on the validation set. We then added the neural circuit measures into our predictor set to identify the combination of neural circuit dysfunctions and physiological markers that accurately predict each symptom subtype. Achieving 54% accuracy suggested a strong relationship between those neural-physiological predictors and the mental states that characterize each subtype. Further work to elucidate the complex relationships between physiological markers, neural circuit dysfunction and resulting symptoms would advance our understanding of the pathophysiological pathways underlying depression and anxiety.

Abnormal cortisol awakening responses in patients with neurotic and personality disorders admitted for psychotherapy in day hospital

Dysregulation of the hypothalamic-pituitary-adrenal axis (HPA axis) has been associated with various psychiatric conditions. The most interesting parameter of the HPA axis function is cortisol awakening response (CAR). Few data exist about the CAR in anxiety or personality disorders and findings are often contradictory showing blunted or increased CAR compared with control groups. The goal of this study was to determine whether patients with neurotic and personality disorders show a specific CAR pattern. The study population comprised 130 patients, mainly females (71.5%), with the primary diagnosis of a neurotic disorder or personality disorder according to ICD-10 admitted for psychotherapy in a day hospital. Pre-treatment cortisol levels were measured in three saliva samples collected in one day. The Symptom Checklist "O" and MMPI-2 were used to assess the pre-treatment levels of patients' symptoms and personality traits. The study revealed a high percentage of CAR non-responders (cortisol increase of less than 2.5 nmol/l) in the study group (43.1%), particularly in females. 49% of them were CAR non-responders compared with 28% in males and 25% in the general population, respectively. CAR non-responders did not differ from the remainder in clinical characteristics. Four different CAR patterns were found in the study group: negative (26.9%), blunted (26.1%), normal (25.4%) and elevated (21.6%) as well as a particular type was not related to clinical characteristics of the patients. The study suggests that abnormal CAR types are observed in patients with neurotic and personality disorders and further research into the mechanism of the findings is required.

Expected Estimation Errors in Studies of the Cortisol Awakening Response: A Simulation

OBJECTIVE

Misestimation as a consequence of small sample sizes, small effect sizes, and noisy measurement may be particularly problematic in biomarker studies, the cost of which can adversely affect design decisions. This simulation study used real study designs reported in a meta-analysis of psychosocial correlates of the cortisol awakening response to investigate the probability that the results of these designs would yield misestimates in a cross-sectional study.

METHODS

For each of the 212 designs, 100,000 simulated data sets were produced and the percentages of effects that were in the wrong direction and/or that differed by more than 0.10 from the true effect (b = 0.10) were calculated.

RESULTS

As expected, small samples (n < 100) and noisy measurement contributed to higher probability of errors. The average probability of an effect being in the wrong direction was around 20%, with some designs reaching 40%; misestimation probabilities were around 40%, with some designs reaching 80%. This was true for all studies as well as those reporting statistically significant effects.

CONCLUSION

Results call for better study designs, and this article provides suggestions for how to achieve more accurate estimates.

Stress and Health: A Review of Psychobiological Processes

The cumulative science linking stress to negative health outcomes is vast. Stress can affect health directly, through autonomic and neuroendocrine responses, but also indirectly, through changes in health behaviors. In this review, we present a brief overview of (a) why we should be interested in stress in the context of health; (b) the stress response and allostatic load; (c) some of the key biological mechanisms through which stress impacts health, such as by influencing hypothalamic-pituitary-adrenal axis regulation and cortisol dynamics, the autonomic nervous system, and gene expression; and (d) evidence of the clinical relevance of stress, exemplified through the risk of infectious diseases. The studies reviewed in this article confirm that stress has an impact on multiple biological systems. Future work ought to consider further the importance of early-life adversity and continue to explore how different biological systems interact in the context of stress and health processes.

Maternal depression and inflammation during pregnancy

BACKGROUND

Maternal depression during pregnancy increases the risk for adverse developmental outcomes in children. However, the underpinning biological mechanisms remain unknown. We tested whether depression was associated with levels of and change in the inflammatory state during pregnancy, if early pregnancy overweight/obesity or diabetes/hypertensive pregnancy disorders accounted for/mediated these effects, and if depression added to the inflammation that typically accompanies these conditions.

METHODS

We analyzed plasma high-sensitivity C-reactive protein (hsCRP) and glycoprotein acetyls at three consecutive stages during pregnancy, derived history of depression diagnoses before pregnancy from Care Register for Healthcare (HILMO) (N = 375) and self-reports (N = 347) and depressive symptoms during pregnancy using the Center for Epidemiological Studies Depression Scale completed concurrently to blood samplings (N = 295). Data on early pregnancy body mass index (BMI) and diabetes/hypertensive pregnancy disorders came from medical records.

RESULTS

Higher overall hsCRP levels, but not change, during pregnancy were predicted by history of depression diagnosis before pregnancy [HILMO: mean difference (MD) = 0.69 standard deviation (s.d.) units; 95% confidence interval (CI) 0.26-1.11, self-report: MD = 0.56 s.d.; 95% CI 0.17-0.94] and higher depressive symptoms during pregnancy (0.06 s.d. per s.d. increase; 95% CI 0.00-0.13). History of depression diagnosis before pregnancy also predicted higher overall glycoprotein acetyls (HILMO: MD = 0.52 s.d.; 95% CI 0.12-0.93). These associations were not explained by diabetes/hypertensive disorders, but were accounted for and mediated by early pregnancy BMI. Furthermore, in obese women, overall hsCRP levels increased as depressive symptoms during pregnancy increased (p = 0.006 for interaction).

CONCLUSIONS

Depression is associated with a proinflammatory state during pregnancy. These associations are mediated by early pregnancy BMI, and depressive symptoms during pregnancy aggravate the inflammation related to obesity.

Disaster-related prenatal maternal stress, and childhood HPA-axis regulation and anxiety: The QF2011 Queensland Flood Study

BACKGROUND

The fetal programming hypothesis suggests that prenatal maternal stress (PNMS) influences aspects of fetal development, such as the Hypothalamic Pituitary Adrenal (HPA) axis, enhancing susceptibility to emotional problems. No study (to our knowledge) has investigated this pathway considering development of preschool anxiety symptoms. Using data from the Queensland Flood study (QF2011), our objective was to determine whether toddler HPA-axis functioning mediated the association between aspects of flood-related PNMS and child anxiety symptoms at 4-years, and whether relationships were moderated by the timing of the stressor in utero or by the child's sex.

METHODS

Women, pregnant during the 2011 Queensland floods (N = 230), were recruited soon afterwards and completed questionnaires regarding their objective hardship (e.g., loss of personal property), subjective distress (post-traumatic-like symptoms) and cognitive appraisal of the disaster. At 16 months, indexes of the child's diurnal cortisol rhythm (awakening response, total daily output, diurnal slope [N = 80]), and stress reactivity (N = 111), were obtained. At 4-years, N = 117 mothers reported on their own mood and their children's anxiety symptoms; of these, N = 80 also had valid child cortisol reactivity data, and N = 64 had diurnal cortisol rhythm data.

RESULTS

A greater cortisol awakening response at 16 months mediated the relationship between subjective PNMS and anxiety symptoms at 4-years. Greater toddler daily cortisol secretion predicted more anxiety symptoms, independent of PNMS. The laboratory stressor did not elicit a cortisol response. PNMS effects were not dependent upon child sex nor on gestational timing of flood exposure.

CONCLUSIONS

Indexes of diurnal cortisol in toddlerhood may represent vulnerability for anxiety symptoms in preschoolers, both independent of, and following, exposure to disaster-related prenatal maternal subjective distress.

Role Fulfillment Mediates the Association Between Daily Family Assistance and Cortisol Awakening Response in Adolescents

Family assistance (helping the family) is associated with both positive and negative psychological and biological outcomes during adolescence. However, the association between family assistance and the hypothalamic-pituitary-adrenal (HPA) axis remains unstudied. Thus, we assess how helping the family relates to adolescents' diurnal cortisol, an index of HPA activity, and psychological outcomes. Three hundred and seventy ethnically diverse adolescents (ages 11-18) reported daily helping behaviors and psychological experiences for 14 days and provided four saliva samples per day for 4 days. Multilevel modeling revealed that cortisol awakening response was lower the day after adolescents helped their families more. This association was explained, in part, by perceived role fulfillment (feeling like a good son, daughter, and sibling). Results highlight a possible psychological and biological benefit of assisting the family during adolescence.

Basolateral Amygdala Connectivity With Subgenual Anterior Cingulate Cortex Represents Enhanced Fear-Related Memory Encoding in Anxious Humans

BACKGROUND

The amygdala can enhance emotional memory encoding as well as anxiogenesis via corticotropin-releasing factor neurons. However, the amygdala's explicit role in emotional encoding remains unclarified in humans. We examined how functional connectivity (FC) of amygdala subnuclei affects emotional encoding, considering its mechanism in which anxiety, attention, and cortisol conceivably participate.

METHODS

A total of 65 healthy humans underwent resting-state functional magnetic resonance imaging scans and saliva collection at 10 points in time over 2 days. FC analysis was performed for basolateral amygdala subnucleus (BLA) and centromedial amygdala subnucleus. We assessed attentional control via an emotional Stroop task and assessed emotional encoding via a facial identification task that examines how strongly a neutral face is memorized when accompanied by an emotional face (fearful, sad, or happy). FC and task performance were compared between high-anxious and non-high-anxious groups classified by anxious personality scores.

RESULTS

BLA connected with subgenual anterior cingulate cortex (sgACC) in proportion to the strength of fear-related encoding, whereas centromedial subnucleus connected with caudate nucleus for happy-related encoding. The high-anxious group showed more enhanced fear-related encoding but impaired happy-related encoding compared with the non-high-anxious group. BLA-sgACC FC was more intensified in the high-anxious group than in the non-high-anxious group; however, centromedial-caudate FC did not differ between them. Although emotional encoding was uncorrelated with either attentional control or cortisol, BLA-sgACC was positively correlated with cortisol increase after awakening.

CONCLUSIONS

The study revealed that neural interactions of BLA, specifically with sgACC, might play a critical role in fear-related memory encoding, depending on the individual's level of anxiety. These findings aid in understanding the complicated mechanisms of emotional memory in anxiety disorders.

Depression and sleep: what has the treatment research revealed and could the HPA axis be a potential mechanism?

Research indicates that insomnia improvement plays a critical role in depression symptom improvement. In line with the National Institute of Mental Health Experimental Therapeutics approach recent research focuses on identifying specific mechanisms; the present manuscript aims to review recent research on one potential mechanism, dysfunction in the HPA axis which is a shared biological substrate of both depression and insomnia. Over the past five years, research demonstrated a relationship between sleep disturbance and cortisol reactivity and recovery following a stressor. Meanwhile, research on the relationship between depression and HPA axis functioning is less consistent and is dependent on measurement of HPA axis. Experimental research that aims to determine a causal pathway between sleep, depression and HPA axis functioning is needed.