The awakening cortisol response: methodological issues and significance

Diurnal cortisol measures are distinctively associated with evaluation of neuroticism by self and others

The link between neuroticism and the various indicators of daily cortisol fluctuations is frequently noted to be inconsistent or lacking in strength. The current study aimed to investigate the predictive capacity of both self-assessment and external evaluations of neuroticism, along with their interaction, on multiple indices of diurnal cortisol variations. This research involved the assessment of neuroticism using self-report and external evaluations among 166 working individuals, coupled with the collection of saliva samples over two consecutive workdays. Employing multilevel response surface analysis, our findings indicated that self-reported neuroticism exhibited a stronger association with cortisol indices compared to external evaluations. Additionally, the level of alignment between self-assessment and external ratings of neuroticism specifically impacted the prediction of estimates of daily cortisol production. We discuss the theoretical and practical implications of these results.

Stress and diurnal cortisol among Latino/a college students: A multi-risk model approach

The transition to college is a time of increased opportunity and stress spanning multiple domains. Adolescents who encounter significant stress during this transition may be vulnerable to adverse outcomes due to a "wear and tear" of the hypothalamic pituitary adrenal (HPA) axis. Latino/a students may be particularly at-risk for heightened stress exposure due to experiences of both minority-specific and general life stress. Despite this, little is known regarding the cumulative impact of multiple stressors on Latino/a students' HPA axis functioning. The present study employed a "multi-risk model" approach to examine additive, common, and cumulative effects of multiple stress forms (general, academic, social, financial, bicultural, ethnic/racial discrimination) on diurnal cortisol in a sample of first-year Latino/a college students (N = 196; 64.4% female; Mage = 18.95). Results indicated that no stress forms were additively associated with the cortisol awakening response (CAR), but general stress was associated with a flatter diurnal cortisol slope (DCS) and bicultural stress was linked with a steeper DCS. A college stress latent factor was associated with a lower CAR, whereas a latent factor of discrimination was not associated with diurnal cortisol. Cumulative risk was linked with a lower CAR. Findings highlight the physiological correlates of various stressors experienced by Latino/a college students.

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.

Relationship of sleep with diurnal cortisol rhythm considering sleep measurement and cortisol sampling schemes

Information on the relationships between the previous night's sleep and the next-day diurnal cortisol rhythm is inconsistent due to confounding factors such as sleep measurements (trait/state sleep and objective/subjective sleep) and cortisol sampling schemes. Therefore, this study aimed to investigate these relationships, considering the confounding factors. College students (n = 79) wore actigraphy for 3 days to undergo an evaluation of previous night-time sleep objectively and reported their subjective sleep parameters in a sleep diary. In addition, participants provided six salivary cortisol samples daily. Furthermore, six cortisol sampling schemes were created to reflect diurnal cortisol rhythms, and two different methods were used to calculate the index of diurnal cortisol slope (DCS). A multilevel model was created to examine the impact of both trait and state sleep on next-day diurnal cortisol rhythm. The results revealed that higher objective state sleep efficiency and longer objective state total sleep time were associated with a higher cortisol awakening response (CAR). Moreover, higher objective trait sleep efficiency and longer objective trait total sleep time were associated with higher waking cortisol levels and steeper DCS. In addition, a minimum of four saliva samples were required at different time points, including upon waking, 30 min after waking, 1 h after waking, and at bedtime, to explore the relationship of sleep efficiency/total sleep time with waking cortisol, CAR, and DCS. Furthermore, the index of the peak-to-bed slope was appropriately employed to examine the relationship between sleep efficiency and DCS, whereas the wake-to-bed slope was effective for examining the relationship between total sleep time and DCS. In summary, this study clarified the relationship between sleep and next-day diurnal cortisol rhythm and suggested a cost-effective cortisol sampling schedule and calculation methods.

Variation in diurnal cortisol patterns among the Indigenous Shuar of Amazonian Ecuador

OBJECTIVES

The hypothalamic-pituitary-adrenal (HPA) axis and its primary end product, the glucocorticoid cortisol, are major components of the evolved human stress response. However, most studies have examined these systems among populations in high-income settings, which differ from the high pathogen and limited resource contexts in which the HPA axis functioned for most of human evolution.

METHODS

We investigated variability in diurnal salivary cortisol patterns among 298 Indigenous Shuar from Amazonian Ecuador (147 males, 151 females; age 2-86 years), focusing on the effects of age, biological sex, and body mass index (BMI) in shaping differences in diurnal cortisol production. Saliva samples were collected three times daily (waking, 30 minutes post-waking, evening) for three consecutive days to measure key cortisol parameters: levels at waking, the cortisol awakening response, the diurnal slope, and total daily output.

RESULTS

Age was positively associated with waking levels and total daily output, with Shuar juveniles and adolescents displaying significantly lower levels than adults (p < .05). Sex was not a significant predictor of cortisol levels (p > .05), as Shuar males and females displayed similar patterns of diurnal cortisol production across the life course. Moreover, age, sex, and BMI significantly interacted to moderate the rate of diurnal cortisol decline (p = .027). Overall, Shuar demonstrated relatively lower cortisol concentrations than high-income populations.

CONCLUSIONS

This study expands the documented range of global variation in HPA axis activity and diurnal cortisol production and provides important insights into the plasticity of human stress physiology across diverse developmental and socioecological settings.

No evidence for relationship between paternal post-partum depressive symptoms and testosterone or cortisol in first-time fathers

Male life history strategies are regulated by the neuroendocrine system. Testosterone (T) and cortisol regulate male behaviors including parenting and facilitate managing tradeoffs at key transitions in development such as first-time fatherhood. Both hormones demonstrate marked fluctuations in the postnatal period, and this presents an opportunity to investigate the role of T and cortisol in postpartum depressive symptoms-comparably less studied in fathers than in mothers in the evolutionary literature. Prior work on depressive symptoms has yet to integrate insights from the "dual hormone hypothesis (DHH)" which has focused on how T and cortisol interact to jointly regulate traits associated with dominance and status-seeking (i.e., mating effort) but has yet to be included in models of parenting effort. In this research, we use secondary data to investigate the relationship between DHH and traits ostensibly opposed to status seeking (i.e., depressive symptoms). First-time fathers (n = 193) provided morning saliva samples 10 months following parturition and reported on the presence of depressive symptoms (BDI-II). Responses were decomposed into three factors: cognitive, affective, and somatic. Using hybrid latent variable structural equation modeling, we did not find evidence that T predicted variability in cognitive, affective, or somatic depressive symptom factors. We found a null effect for cortisol as well. Finally, we could not find evidence that the DHH variable (T × cortisol interaction) predicted any variability in cognitive, affective, or somatic depressive symptoms. While we did not find evidence to support our hypotheses using a secondary data set, this study contributes to research on the neuroendocrinology of depression in fathers. Discussion focuses on the limitations of sample demographics, timing of saliva and self-report collection, and the lack of extant theory specific to paternal postpartum depression.

Maltreatment type differences in cortisol stress response trajectories across adolescence

This study examined cortisol stress response trajectories across adolescence in 454 maltreated and comparison youth recruited from Los Angeles County between 2002 and 2005 (66.7% maltreated; 46.7% girls; 39.0% Latino; 37.7% Black; 12.3% Mixed or Biracial; 11.0% White; Mage  = 10.9 years, SD = 1.2). Adolescents' peak activation and cortisol reactivity and recovery slopes following the Trier Social Stress Test for Children were calculated at four waves, then used to model peak activation and cortisol reactivity and recovery trajectories arrayed by age. Maltreated youth had blunted cortisol reactivity at age 9 relative to comparison youth (b = -.19, p = .02). Sexually and physically abused youth showed blunted cortisol reactivity and recovery trajectories relative to emotionally abused and neglected youth.

Acute stress impairs visual path integration

Acute stress exerts substantial effects on episodic memory, which are often mediated by glucocorticoids, the end-product of the hypothalamic-pituitary-adrenal axis. Surprisingly little is known, however, about the influence of acute stress on human spatial navigation. One specific navigational strategy is path integration, which is linked to the medial entorhinal cortex, a region harboring glucocorticoid receptors and thus susceptible for stress effects. Here, we investigated effects of acute stress on path integration performance using a virtual homing task. We divided a sample of healthy young male participants into a stress group (nstress = 32) and a control group (ncontrol = 34). The stress group underwent the socially evaluated cold-pressor test, while the control group underwent a non-stressful control procedure. Stress induction was confirmed via physiological and subjective markers, including an increase of salivary cortisol concentrations. We applied linear mixed models to investigate the effect of acute stress on path integration depending on task difficulty and the presence or absence of spatial cues. These analyses revealed that stress impaired path integration especially in trials with high difficulty and led to greater decline of performance upon removal of spatial cues. Stress-induced deficits were strongly related to impaired distance estimation, and to a lesser extent to compromised rotation estimation. These behavioral findings are in accordance with the hypothesis that acute stress impairs path integration processes, potentially by affecting the entorhinal grid cell system. More generally, the current data suggests acute stress to impair cognitive functions mediated by medial temporal lobe regions outside the hippocampus.

Experiences of adversity in childhood and adolescence and cortisol in late adolescence

Early life adversity influences the diurnal cortisol rhythm, yet the relative influence of different characteristics of adversity remains unknown. In this study, we examine how developmental timing (childhood vs. adolescence), severity (major vs. minor), and domain of early life adversity relate to diurnal cortisol rhythms in late adolescence. We assessed adversity retrospectively in early adulthood in a subsample of 236 participants from a longitudinal study of a diverse community sample of suburban adolescents oversampled for high neuroticism. We used multilevel modeling to assess associations between our adversity measures and the diurnal cortisol rhythm (waking and bedtime cortisol, awakening response, slope, and average cortisol). Major childhood adversities were associated with flatter daily slope, and minor adolescent adversities were associated with greater average daily cortisol. Examining domains of childhood adversities, major neglect and sexual abuse were associated with flatter slope and lower waking cortisol, with sexual abuse also associated with higher cortisol awakening response. Major physical abuse was associated with higher waking cortisol. Among adolescent adversities domains, minor neglect, emotional abuse, and witnessing violence were associated with greater average cortisol. These results suggest severity, developmental timing, and domain of adversity influence the association of early life adversity with stress response system functioning.

The phenotypic associations and gene-environment underpinnings of socioeconomic status and diurnal cortisol secretion in adolescence

While converging evidence suggests that both environmental and genetic factors underlie variations in diurnal cortisol, the extent to which these sources of influence vary according to socioeconomic status (SES) has seldom been investigated, particularly in adolescence. To investigate whether a distinct genetic and environmental contribution to youth's diurnal cortisol secretion emerges according to family SES and whether the timing of these experiences matters. Participants were 592 twin pairs, who mostly came from middle-income and intact families and for whom SES was measured in childhood and adolescence. Diurnal cortisol was assessed at age 14 at awakening, 30 min later, in the afternoon and evening over four nonconsecutive days. SES-cortisol phenotypic associations were specific to the adolescence period. Specifically, higher awakening cortisol levels were detected in wealthier backgrounds, whereas higher cortisol awakening response (CAR) and diurnal changes were present at both ends of the SES continuum. Moreover, smaller genetic contributions emerged for awakening cortisol in youth from poorer compared to wealthier backgrounds. The results suggest that the relative contribution of inherited factors to awakening cortisol secretion may be enhanced or suppressed depending on the socio-family context, which may help to decipher the mechanisms underlying later adjustment.

Cortisol dynamics in undergraduate nursing students during clinical practice: protocol for an exploratory cross-sectional study

INTRODUCTION

This paper presents a protocol for the Investigation of Cortisol Dynamics in Undergraduate Nursing Students, a funded project aiming to understand the fluctuations in anxiety and salivary cortisol levels due to clinical setting changes and the anxiety associated with clinical practice.

METHODS AND ANALYSIS

This study is an exploratory, cross-sectional, observational study that will be conducted at a health and science school in Portugal. Data collection will involve phycological assessment instruments for personality, anxiety, stress, depression and saliva cortisol levels. The target population consists of undergraduate nursing students enrolled in our institution for the academic year of 2022/2023 (N=272), of whom we aim to recruit 35% (N=96) to the study.

ETHICS AND DISSEMINATION

The project obtained approval from the Institutional Review Board of the Egas Moniz-Cooperativa de Ensino Superior, CRL, on 5 July 2022 (ID: 116/21.22) and ethical approval from the Egas Moniz Ethics Committee on 28 July 2022 (ID:1110.22). Informed consent will be obtained from those who wish to participate, ensuring students' voluntary participation in the project. The results of this study will be disseminated through open-access peer-reviewed publications and presented at scientific events.

Adverse Childhood Experiences Predict Diurnal Cortisol Throughout Gestation

OBJECTIVE

Adverse childhood experiences (ACEs) are associated with negative prenatal and perinatal health outcomes and may, via these pathways, have intergenerational effects on child health and development. We examine the impact of ACEs on maternal salivary cortisol, a key measure of prenatal biology previously linked with pregnancy-related health outcomes.

METHODS

Leveraging assessments across three trimesters, we used linear mixed-effects models to analyze the influence of ACEs on maternal prenatal diurnal cortisol patterns in a diverse cohort of pregnant women (analytic sample, n = 207). Covariates included comorbid prenatal depression, psychiatric medications, and sociodemographic factors.

RESULTS

Maternal ACEs were significantly associated with flatter diurnal cortisol slopes (i.e., less steep decline), after adjusting for covariates, with effects consistent across gestation (estimate = 0.15, standard error = 0.06, p = .008).

CONCLUSIONS

ACEs experienced before pregnancy may have a robust and lasting influence on maternal prenatal hypothalamic-pituitary-adrenal activity throughout gestation, a key biological marker associated with perinatal and child health outcomes. The findings suggest one route of intergenerational transmission of early adverse experiences and underscore the potential value of assessing prepregnancy adverse experiences for promoting perinatal and maternal and child health.

Are all parental experiences equal?: Cluster analysis of salivary cortisol and perception of parental stress in mothers of children with autism spectrum disorder

Many parents of children with autism spectrum disorder (ASD) report high stress levels related to their parenting role. The experience of stress is reflected in physical symptoms and well-being, as observed by abnormal patterns of cortisol regulation. However, it may be a mistake to conceive parenthood as unilaterally stressful as diverse experiences are possible. Mothers of children with ASD provided salivary cortisol samples and self-rated parental stress. The area under the curve with respect to ground was calculated in regard to three daily collection time points. As a group, mothers reported average levels of parenting stress and flat daily cortisol output. The current age of the child and age at the time of diagnosis moderately predicted overall daily cortisol. Hierarchical clusters analysis identified four distinct profiles of stress regulation based on daily cortisol regulation and perception of parental stress. Groups did not differ based on the severity of symptoms related to autism or demographic information. We suggest that other variables, such as stress mediators and secondary stressors, may explain variability in stress regulation. Future research and intervention should perceive the parental experience as heterogeneous and focus on individualizing the support offered in light of diverse experiences.

miRNA-132/212 Deficiency Disrupts Selective Corticosterone Modulation of Dorsal vs. Ventral Hippocampal Metaplasticity

Cortisol is a potent human steroid hormone that plays key roles in the central nervous system, influencing processes such as brain neuronal synaptic plasticity and regulating the expression of emotional and behavioral responses. The relevance of cortisol stands out in the disease, as its dysregulation is associated with debilitating conditions such as Alzheimer's Disease, chronic stress, anxiety and depression. Among other brain regions, cortisol importantly influences the function of the hippocampus, a structure central for memory and emotional information processing. The mechanisms fine-tuning the different synaptic responses of the hippocampus to steroid hormone signaling remain, however, poorly understood. Using ex vivo electrophysiology and wild type (WT) and miR-132/miR-212 microRNAs knockout (miRNA-132/212-/-) mice, we examined the effects of corticosterone (the rodent's equivalent to cortisol in humans) on the synaptic properties of the dorsal and ventral hippocampus. In WT mice, corticosterone predominantly inhibited metaplasticity in the dorsal WT hippocampi, whereas it significantly dysregulated both synaptic transmission and metaplasticity at dorsal and ventral regions of miR-132/212-/- hippocampi. Western blotting further revealed significantly augmented levels of endogenous CREB and a significant CREB reduction in response to corticosterone only in miR-132/212-/- hippocampi. Sirt1 levels were also endogenously enhanced in the miR-132/212-/- hippocampi but unaltered by corticosterone, whereas the levels of phospo-MSK1 were only reduced by corticosterone in WT, not in miR-132/212-/- hippocampi. In behavioral studies using the elevated plus maze, miRNA-132/212-/- mice further showed reduced anxiety-like behavior. These observations propose miRNA-132/212 as potential region-selective regulators of the effects of steroid hormones on hippocampal functions, thus likely fine-tuning hippocampus-dependent memory and emotional processing.

Diurnal variability of cortisol in the Pennsylvania adult smoking study: Exploration of association with nicotine intake

Cortisol in saliva, urine and plasma follows a diurnal rhythm typically characterized as a morning peak and a decline throughout the waking day. While often measured under controlled conditions, inter-individual differences in cortisol diurnal rhythms in free living populations are not well characterized. Cortisol levels may vary substantially between individuals and the level of variation may differ depending on the time of day. Further, associations with individual characteristics such as nicotine dependence on cortisol rhythms have not been adequately determined. We developed a Liquid Chromatography-Tandem Mass Spectrometry method to measure cortisol in saliva of 180 smokers from the Pennsylvania Adult Smoking Study. Diurnal patters of cortisol were determined by obtaining five timed samples throughout the day for a total of 900 determinations. Adherence to the protocol was estimated by asking participants to record the time of sample collection. Longitudinal linear mixed effects models were developed to measure the predictors of mean levels. Phenotypic groups were constructed based on the minimum and maximum cortisol levels. Mixed method modelling was conducted to determine the effects of phenotype and study adherence as well as reported measures of stress, nicotine dependence and cigarette smoking frequency. Nicotine metabolites were measured to accurately quantify dose of smoking intake. Results showed that there was moderate compliance to the timed protocol. Descriptive and analytic findings showed that some smokers had atypical cortisol patterns, and that the cortisol profiles based on experience of maximum and minimum cortisol levels can predict how cortisol varies throughout the day. There was no association with reported stress, cigarettes per day, and nicotine metabolites. There was no association with the Fagerstrom Test for Nicotine Dependence. The Hooked on Nicotine Checklist (HONC) score was associated with decreased cortisol levels. Overall these results show new approaches and expectations to population-based studies of cortisol.

Beyond sleep: A multidimensional model of chronotype

Chronotype can be defined as an expression or proxy for circadian rhythms of varied mechanisms, for example in body temperature, cortisol secretion, cognitive functions, eating and sleeping patterns. It is influenced by a range of internal (e.g., genetics) and external factors (e.g., light exposure), and has implications for health and well-being. Here, we present a critical review and synthesis of existing models of chronotype. Our observations reveal that most existing models and, as a consequence, associated measures of chronotype have focused solely or primarily on the sleep dimension, and typically have not incorporated social and environmental influences on chronotype. We propose a multidimensional model of chronotype, integrating individual (biological and psychological), environmental and social factors that appear to interact to determine an individual's true chronotype with potential feedback loops between these factors. This model could be beneficial not only from a basic science perspective but also in the context of understanding health and clinical implications of certain chronotypes as well as designing preventive and therapeutic approaches for related illnesses.

Physical Activity and Cortisol Regulation: A Meta-Analysis

Physical activity participation is associated with effective stress coping, indicated by decreases in both physiological stress reactivity and perceived stress. Quantifying the effect of physical activity on the diurnal regulation of one key physiological stress indicator, the stress hormone, cortisol, across studies may demonstrate the extent to which physical activity participation is associated with diurnal HPA axis regulation. We meta-analyzed studies examining relations between physical activity participation and indices of HPA axis regulation: the diurnal cortisol slope and the cortisol awakening response. We also examined moderators of the relation. The analysis revealed a small, non-zero negative averaged correlation between physical activity and the diurnal cortisol slope (r = -0.043, 95% CI [-0.080, -0.004]). Examination of sample sociodemographic differences, study design characteristics, cortisol measurement methods, and physical activity variables as moderators revealed few effects on the relation between physical activity and diurnal cortisol slope. We did not observe lower levels of variability in the mean cortisol awakening response at higher levels of physical activity participation, and moderator analyses showed little evidence of reductions in heterogeneity for this effect. We found some evidence of systematic publication bias. Findings suggest higher physical activity is associated with a steeper diurnal cortisol slope. However, the cortisol awakening response did not differ by physical activity level. Future studies testing the physical activity and cortisol regulation association should use standardized physical activity measures, follow guidelines for better quality cortisol sampling collection and analysis, and test relations in large-scale empirical studies to confirm the direction and causality of the effect.

CARWatch - A smartphone application for improving the accuracy of cortisol awakening response sampling

BACKGROUND

Many studies investigating the cortisol awakening response (CAR) suffer from low adherence to the study protocol as well as from the lack of precise and objective methods for assessing the awakening and saliva sampling times which leads to measurement bias on CAR quantification.

METHODS

To address this issue, we have developed "CARWatch", a smartphone application that aims to enable low-cost and objective assessment of saliva sampling times as well as to concurrently increase protocol adherence. As proof-of-concept study, we assessed the CAR of N = 117 healthy participants (24.2 ± 8.7 years, 79.5% female) on two consecutive days. During the study, we recorded awakening times (AW) using self-reports, the CARWatch application, and a wrist-worn sensor, and saliva sampling times (ST) using self-reports and the CARWatch application. Using combinations of different AW and ST modalities, we derived different reporting strategies and compared the reported time information to a Naive sampling strategy assuming an ideal sampling schedule. Additionally, we compared the AUC_I, computed using information from different reporting strategies, against each other to demonstrate the effect of inaccurate sampling on the CAR.

RESULTS

The use of CARWatch led to a more consistent sampling behavior and reduced sampling delay compared to self-reported saliva sampling times. Additionally, we observed that inaccurate saliva sampling times, as resulting from self-reports, were associated with an underestimation of CAR measures. Our findings also revealed potential error sources for inaccuracies in self-reported sampling times and showed that CARWatch can help in better identifying, and possibly excluding, sampling outliers that would remain undiscovered by self-reported sampling.

CONCLUSION

The results from our proof-of-concept study demonstrated that CARWatch can be used to objectively record saliva sampling times. Further, it suggests its potential of increasing protocol adherence and sampling accuracy in CAR studies and might help to reduce inconsistencies in CAR literature resulting from inaccurate saliva sampling. For that reason, we published CARWatch and all necessary tools under an open-source license, making it freely accessible to every researcher.

Stress and the hypothalamic-pituitary-adrenal axis: How can the COVID-19 pandemic inform our understanding and treatment of acute insomnia?

Stress and sleep are very closely linked, and stressful life events can trigger acute insomnia. The ongoing COVID-19 pandemic is highly likely to represent one such stressful life event. Indeed, a wide range of cross-sectional studies demonstrate that the pandemic is associated with poor sleep and sleep disturbances. Given the high economic and health burden of insomnia disorder, strategies that can prevent and treat acute insomnia, and also prevent the transition from acute insomnia to insomnia disorder, are necessary. This narrative review outlines why the COVID-19 pandemic is a stressful life event, and why activation of the hypothalamic-pituitary-adrenal axis, as a biological marker of psychological stress, is likely to result in acute insomnia. Further, this review outlines how sleep disturbances might arise as a result of the COVID-19 pandemic, and why simultaneous hypothalamic-pituitary-adrenal axis measurement can inform the pathogenesis of acute insomnia. In particular, we focus on the cortisol awakening response as a marker of hypothalamic-pituitary-adrenal axis function, as cortisol is the end-product of the hypothalamic-pituitary-adrenal axis. From a research perspective, future opportunities include identifying individuals, or particular occupational or societal groups (e.g. frontline health staff), who are at high risk of developing acute insomnia, and intervening. From an acute insomnia treatment perspective, priorities include testing large-scale online behavioural interventions; examining if reducing the impact of stress is effective and, finally, assessing whether "sleep vaccination" can maintain good sleep health by preventing the occurrence of acute insomnia, by preventing the transition from acute insomnia to insomnia disorder.

Saliva Cortisol as a Biomarker of Injury in Youth Sport-Related Concussion

Increasing rates of sport-related concussion (SRC) in youth impose a significant burden on public health systems and the lives of young athletes. Accurate prediction for those likely to develop persistent post-concussion symptomology (PPCS) using a fluid biomarker, reflecting both acute injury and recovery processes, would provide the opportunity for early intervention. Cortisol, a stress hormone released through the hypothalamic-pituitary-adrenal (HPA) axis following injury, may provide a missing physiological link to clinical recovery. This cohort study investigated the change in saliva cortisol following SRC and the association between cortisol and symptom burden in pediatric ice hockey players. Further, the association between cortisol levels and medical clearance to return to play was explored. In total, cortisol samples from 233 players were included; 165 athletes (23.6% female) provided pre-injury saliva and 68 athletes (19.1% female) provided post-SRC saliva samples for cortisol analysis. Quantile (median) regressions were used to compare cortisol between pre-injury and post-SRC groups, and the association between total symptoms (/22) and symptom severity scores (/132) reported on the Sport Concussion Assessment Tool (SCAT)3/SCAT5 and post-SRC cortisol (adjusting for age, sex, history of concussion, and time from injury to sample collection). Results demonstrated significantly lower saliva cortisol in post-SRC athletes compared with the pre-injury group (β = -0.62, 95% confidence interval [CI; -1.08, -0.16], p = 0.009). Post-SRC cortisol was not significantly associated with the SCAT3/SCAT5 symptom totals or symptom severity scores; however, females were found to report more symptoms (β = 6.95, 95% CI [0.35, 13.55], p = 0.040) and greater symptom severity (β = 23.87, 95% CI [9.58, 38.15], p = 0.002) compared with males. Exploratory time-to-event analysis revealed a point estimate suggesting a potential association between low cortisol levels and days to medical clearance to return to play. Although preliminary, these findings suggest that the HPA axis may be dysregulated post-SRC. Further, our exploratory analysis and case presentation of post-injury outliers highlight the need to further research cortisol as a prognostic biomarker to inform individualized sex-specific care after SRC.

Hair Cortisol Concentration as a Biomarker of Symptoms of Depression in the Perinatal Period

Pregnancy is a sensitive period when women experience major hormonal and psychological changes. A high prevalence of the symptoms of depression and manifested major depression rates have been reported during this period, leading to negative outcomes both for mothers and the offspring. Despite its prevalence, the aetiology of depression is not yet fully understood. Nonetheless, alterations in cortisol levels have been proposed as a reliable biomarker to identify pregnant women at risk of perinatal depression. Hair cortisol has recently been extensively used in bio-psychological studies as a suitable non-invasive biomarker for several neuropsychiatric disorders. Various studies have published evidence regarding the relationship between cortisol fluctuations during the perinatal period, measured both in hair and in other substrates, and the onset of perinatal symptoms of depression. This current review provides an overview of cortisol level changes measured in women's hair during pregnancy or the postpartum period and its association with perinatal symptoms of depression. Further studies, including repetitive measurement of both hair cortisol and depression throughout the prenatal period, must be performed to clarify the relationship between cortisol levels and perinatal symptoms of depression.

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.

Effectiveness of mindfulness training on pregnancy stress and the hypothalamic-pituitary-adrenal axis in women in China: A multicenter randomized controlled trial

Introduction

In the past two decades, mindfulness-based intervention programs have gradually become popular.Many studies have confirmed that these programs can effectively alleviate prenatal stress and negative emotion.The mindfulness-based stress-buffering hypothesis suggests that mindfulness training can induce changes in the levels of the cortisol secreted by the HPA axis, thereby reducing stress susceptibility. However, to date, only a few high-quality evidence-based medical studies have analyzed the effect of the mindfulness-based intervention in a maternal population.Thus, this study investigated the effects of a mindfulness-based psychosomatic intervention on pregnancy stress and the HYPERLINK "javascript:;" hypothalamic-pituitary-adrenal (HPA) axis of pregnant Chinese women.

Methods

Women experiencing first-time pregnancy (n = 117) were randomly allocated to the intervention group or parallel active control group, and data were collected at baseline and post-intervention periods. The participants completed questionnaires regarding mindfulness and pregnancy stress. Saliva samples was collected at the time of waking up, and 30, 45, and 60 min after waking up for analyzing the salivary cortisol levels. We analyzed differences between the two groups and changes within the same group before and after the intervention.

Results and discussion

A total of 95 participants completed the trial. Compared with the parallel active control group, the intervention group exhibited lower levels of stress after the intervention (P = 0.047). For HPA-axis-related indicators after the intervention, Delta value (P = 0.01) and AUCM value (P = 0.031) of the intervention group were significantly higher than that of the control group. Mindfulness-based interventions effectively reduced the level of pregnancy stress and adjusted the HPA axis function in pregnant women in China.

Clinical Trial Registration

https://www.chictr.org.cn, identifier ChiCTR 2000033149.

Lower diurnal HPA-axis activity in male hypertensive and coronary heart disease patients predicts future CHD risk

BACKGROUND

Coronary heart disease (CHD) and its major risk factor hypertension have both been associated with altered activity of the hypothalamus-pituitary-adrenal (HPA)-axis but the biological mechanisms underlying prospective associations with adverse disease outcomes are unclear. We investigated diurnal HPA-axis activity in CHD-patients, hypertensive (HT) and healthy normotensive men (NT) and tested for prospective associations with biological CHD risk factors.

METHODS

Eighty-three male CHD-patients, 54 HT and 54 NT men repeatedly measured salivary cortisol over two consecutive days. Prospective CHD risk was assessed by changes between baseline and follow-up in the prothrombotic factors D-dimer and fibrinogen, the pro-inflammatory measures interleukin (IL)-6, tumor necrosis factor-alpha (TNF-α), and acute phase protein C-reactive protein (CRP), as well as blood lipids in terms of total cholesterol (tChol)/high-density-lipoprotein cholesterol (HDL)-ratio. We aggregated coagulation and inflammatory measures to respective indices.

RESULTS

The groups differed in repeated daytime cortisol (dayCort) secretion (p=.005,η² _p=.03,f=0.18) and cortisol awakening response (CAR) (p=.006,η² _p=.03,f=0.18), with similarly lower overall dayCort and CAR in CHD-patients and HT, as compared to NT. The groups differed further in cortisol at awakening (p=.015,η² _p=.04,f=0.20) with highest levels in HT (p´s≤.050), and in diurnal slope between waking and evening cortisol (p=.033,η² _p=.04,f=0.20) with steepest slopes in HT (p´s≤.039), although in part not independent of confounders. Lower aggregated dayCort and CAR in terms of area-under-the-curve (AUC) independently predicted increases in future overall CHD risk (AUC_dayCort: p=.021,η² _p=.10,f=0.33;AUC_CAR: p=.028,η² _p=.09,f=0.31) 3.00 ± 0.06(SEM) years later, with risk prediction most pronounced in fibrinogen (AUC_dayCort: p=.017,ΔR ²= 0.12;AUC_CAR: p=.082).

CONCLUSION

We found evidence for an HPA-axis hypoactivity in CHD and HT with lower diurnal HPA-axis activity predicting increases in cardiovascular risk as evidenced by increases in circulating levels of biomarkers of atherothrombotic risk. Down-regulation of basal HPA-axis activity may contribute to the pathogenesis of atherosclerosis and thrombosis in CHD via effects on coagulation.

Reliability of three versus five saliva sampling times for assessing the cortisol awakening response

The cortisol awakening response (CAR) describes the sharp increase in cortisol secretion within 60 min after awakening. A summary of the CAR, the area under the cortisol curve above the awakening cortisol value (AUC_i) is a widely used biomarker in health research. Estimation of the AUC_i rely on a number of collected salivary samples at fixed time intervals (i.e., 5 samples in 15 min intervals) starting from awakening. Little empirical work has been executed to investigate the impact of reducing sampling times on AUC_i estimation, which could potentially improve participant compliance and reduce operational costs. This study aimed to assess the reliability and validity of using 3-sample AUC_i versus 5-sample AUC_i, i.e., systematic and random fluctuations based on a large dataset from healthy and case individuals (total n = 537). We showed that the ideal timing of 3-sampling times was 0-30-60 min with a median difference in AUC_i of - 8 nmol*h/L and interquartile range of 65 nmol*h/L among healthy individuals, and - 12 nmol*h/L and 78 nmol*h/L among case individuals. We subsequently validated the 3-sample AUC_i by re-analyzing three published association studies. Overall, we obtained similar p-values with 3-sample AUC_i when compared to 5-sample AUC_i, while smaller effect sizes and standard errors were observed. In conclusion, despite a less precise estimation of the AUC_i itself, our data support that the AUC measure of the CAR, based on three samples collected at 0-30-60 min from awakening, provides reliable results in association studies.

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.

Cortisol awake response imbalance as an indicator of acute central serous chorioretinopathy: Relationship with choriocapillaris and choroidal features

Purpose

The purpose of the present study was to measure in central serous chorioretinopathy (CSC) the salivary cortisol awake response (CAR) delta percentage (Δ%) variation, a distinct and robust indicator of cortisol rhythm during wakefulness, commonly proposed as a marker of hypothalamic-pituitary adrenal (HPA) axis activity, whose alteration is frequently associated with several adverse health outcomes.

Methods

In the present cross-sectional observational study, salivary CAR Δ% variation was assessed in 17 adult male subjects affected by acute naïve CSC and compared to 17 matched healthy controls. Choroid vasculature metrics were assessed in the study population by measuring the subfoveal choroidal thickness (FCT) and the choroidal vascularity index (CVI) by the imaging technique of enhanced-depth imaging spectral-domain optical coherence tomography (EDI-SD-OCT). Furthermore, flow signal void area features of the choriocapillaris were evaluated in the study population using OCT angiography (OCTA).

Results

Both the control and CSC groups showed a physiological cortisol increase that occurred during the first 30 min after awaking. However, CSC adult male patients showed remarkably blunted CAR Δ% variation in comparison with controls, which might reflect a CSC-related imbalance of HPA axis activity. Statistically significant correlations were shown by Pearson’s correlation test between salivary CAR Δ% and the selected choroidal and choriocapillaris imaging biomarkers (FCT, CVI, and flow signal void area) in the study population.

Conclusion

In conclusion, alterations of the CAR Δ% increase, associated with choroidal-retinal metrics, might provide a window into the physiopathology of acute CSC, suggesting a possible common factor to explain the association between stress and CSC.

Mild to Moderate Sleep Restriction Does Not Affect the Cortisol Awakening Response in Healthy Adult Males

The cortisol awakening response (CAR) is a distinct rise in cortisol that occurs upon awakening that is thought to contribute to arousal, energy boosting, and anticipation. There is some evidence to suggest that inadequate sleep may alter the CAR, but the relationship between sleep duration and CAR has not been systematically examined. Healthy males (n = 111; age: 23.0 ± 3.6 yrs) spent 10 consecutive days/nights in a sleep laboratory. After a baseline night (9 h time in bed), participants spent either 5 h (n = 19), 6 h (n = 23), 7 h (n = 16), 8 h (n = 27), or 9 h (n = 26) in bed for seven nights, followed by a 9 h recovery sleep. The saliva samples for cortisol assay were collected at 08:00 h, 08:30 h and 08:45 h at baseline, on experimental days 2 and 5 and on the recovery day. The primary dependent variables were the cortisol concentration at awakening (08:00 h) and the cortisol area under the curve (AUC). There was no effect of time in bed on either the cortisol concentration at awakening or cortisol AUC. In all the time in bed conditions, the cortisol AUC tended to be higher at baseline and lower on experimental day 5. Five consecutive nights of mild to moderate sleep restriction does not appear to affect the CAR in healthy male adults.

The circadian system modulates the cortisol awakening response in humans

Background

In humans, circulating cortisol usually peaks 30–60 min after awakening from nocturnal sleep, this is commonly referred to as the cortisol awakening response (CAR). We examined the extent to which the CAR is influenced by the circadian system, independent of behaviors including sleep.

Materials and methods

We examined the CAR in 34 adults (20 female) using two complementary multiday in-laboratory circadian protocols performed in dim light, throughout which behavioral factors were uniformly distributed across the 24-hour circadian cycle. Protocol 1 consisted of 10 identical consecutive 5-hour 20-minute sleep/wake cycles, and protocol 2 consisted of 5 identical consecutive 18-hour sleep/wake cycles. Salivary melatonin was used as the circadian phase marker (0° = dim light melatonin onset). During each sleep/wake cycle, salivary cortisol was measured upon scheduled awakening and 50-minutes later, with the change in cortisol defined as the CAR. Cosinor analyses were used to detect any significant circadian rhythmicity in the CAR. In secondary analyses, we adjusted the models for time awake before lights on, total sleep time, percent of rapid eye movement (REM) sleep, and percent of non-rapid eye movement (NREM) sleep.

Results

Both protocols revealed a similar circadian rhythm in the CAR, with peaks occurring at a circadian phase corresponding to 3:40–3:45 a.m., with no detectable CAR during the circadian phases corresponding to the afternoon. In addition to the sinusoidal component of the circadian rhythm, total sleep time was also associated with the CAR for protocol 1. The percent of sleep spent in REM or NREM sleep were not associated with the CAR in either protocol.

Conclusion

Our results show that the CAR exhibits a robust circadian rhythm that persists even after adjusting for prior sleep. Presuming that the CAR optimizes physiological responses to the anticipated stressors related to awakening, these findings may have implications for shift workers who wake up at unusual circadian phases. A blunted CAR in shift workers upon awakening in the evening may result in diminished responses to stressors.

The inflammatory immune system after wake up in healthy male individuals: A highly standardized and controlled study

This study investigates the effects of two light conditions on innate proinflammatory IL-6 cytokines and the cortisol awakening response. The between-subject experiment was conducted with 55 healthy adult-males (aged M_bright = 24.40, SD = 4.58; M_dim = 25.47, SD = 4.96) in a standardized sleep laboratory setting with 60-min light exposure post-awakening. Cortisol significantly increased with bright light exposure as compared to dim light (significant interaction effect). As for IL-6, the main effects of time and light condition were significant, however, the interaction effect between light and time was insignificant. Results replicate stimulatory effects of bright light on cortisol. In general, IL-6 concentrations decreased in both light conditions; however, bright light graphically showed higher concentrations 45–90 min after exposure in comparison to dim light, thus bright light has a potential stimulatory effect on IL-6 production.

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.

The cortisol awakening response at admission to hospital predicts depression severity after discharge in major depressive disorder patients—A replication study

The cortisol awakening response (CAR) is a non-invasive biomarker for hypothalamic-pituitary-adrenal axis (HPA) dysregulation, reflecting accumulated stress over time. In a previous study we reported that a blunted CAR before an inpatient treatment predicted self-reported depressive symptoms six weeks and six months after discharge [Eikeseth, F. F., Denninghaus, S., Cropley, M., Witthöft, M., Pawelzik, M., &amp; Sütterlin, S. (2019). The cortisol awakening response at admission to hospital predicts depression severity after discharge in major depressive disorder (MDD) patients. Journal of Psychiatric Research, 111, 44-50)]. This replication study adopted an improved overall methodology with more stringent assessment protocols and monitoring. The longitudinal design included 122 inpatients from a psychosomatic hospital with a diagnosis of MDD displaying symptoms of moderate to severe major depression (n = 80 females). The CAR was measured at intake. Depression severity was assessed as Beck Depression Inventory II scores at intake, discharge, 6 weeks and 6 months following discharge. Results from the original study were replicated in terms of effect size but did not reach statistical significance (correlation between BDI-II 6 months after discharge and AUCg: r = −0.213; p = 0.054). The replication study yielded nearly identical correlation coefficients as in the original study (BDI-II 6 months and CAR, r = −0.223, p &lt; 0.05). The replication of previously reported effect sizes with a concurrent lack of statistical significance in the more restrictive, larger and better controlled replication study may well inform research on psycho-endocrinological predictors for treatment success, but suggests a rather limited practical relevance for cortisol awakening response measures in this clinical context.

Prenatal diurnal cortisol: Normative patterns and associations with affective symptoms and stress

The hypothalamic-pituitary-adrenal (HPA) axis in pregnancy has attracted considerable research attention, in part, because it may be a mechanism by which diverse prenatal exposures alter perinatal and child health outcomes. Symptoms of affective disturbance and stress are among the most-studied prenatal factors associated with HPA axis alterations, but there remains uncertainty about the nature of the association because of the limitations to, and variability in, data collection and analytic approaches. The current study capitalized on a prospective, longitudinal pregnancy cohort that examined salivary diurnal cortisol, collected at 5 time points across the day, at each trimester in a diverse sample of women. Detailed data on affective symptoms and major life events were collected at each trimester, as were data on health behaviors, medication, and socio-demographics. Results indicated modest stability of individual differences in diurnal cortisol across pregnancy, which was evident for diurnal slope (ICC = .20) and measures of total output (area under the curve, ICC = .25); substantial gestation-related increases in total cortisol output across pregnancy was also observed (p < .001). Adjusting for health behaviors, medication, and socio-demographic covariates, elevated levels of depressive symptoms and major life events were significantly (p < .05) associated with a higher morning awakening value and flatter diurnal slope, which was evident across all trimesters. In addition to the normative gestation-related changes in cortisol production, our results demonstrate selective but robust associations between psychological symptoms, stressors, and the HPA axis across gestation, and suggest both methodological and mechanistic strategies for future study.

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.

Associations between police lethal force errors, measures of diurnal and reactive cortisol, and mental health

Errors in lethal force by police are met with significant demand for explanations as to why they occur, stimulating a growing body of multidisciplinary research. Acutely stressful occupational conditions result in decrements to police performance, including lethal force decision-making. Further, although it is known that repeated and prolonged exposure to potentially traumatic work-related encounters is linked to higher rates of mental health symptoms, it is unclear if psychological symptoms are related to police performance, and lethal force errors specifically. The present study tested the relationships between biological stress and psychological symptoms on lethal force errors among a combined sample of non-clinical, active-duty frontline (n = 57) and tactical (n = 44) police officers. Specifically, biological measures included: diurnal (cortisol awakening response - CAR), and reactive cortisol (prior to and in response to realistic critical incident (CI) simulations). Psychological self-reported symptoms included: pre-CI stress, depression, anxiety, PTSD, and occupational stress. Tactical officers displayed higher CAR compared to frontline officers, consistent with prior research. When including outliers, CAR significantly predicted lethal force decision-making errors; however, the effect does not remain once removing the influence of outlier CAR observations. The current findings suggest that biological measures of reactive cortisol may be too nonspecific to predict lethal force errors during acutely stressful police operations and measures of diurnal cortisol are heavily influenced by outlier values. Non-clinical levels of psychological symptoms (as measured in this study) do not appear to interfere with lethal force decision-making. It remains to be tested if clinically diagnosed disorders would interfere with police performance. Implications for future applied health research are discussed.

Hypothalamic-pituitary-adrenal axis activity and vascular function in healthy adults

OBJECTIVE

The objective of this study is to assess the relationship between hypothalamic-pituitary-adrenal (HPA) axis activity, vascular function and insulin sensitivity in healthy adults.

DESIGN

Open observational study.

PATIENTS

Thirty healthy adults were studied at the Endocrine Research Unit, Repatriation General Hospital, Adelaide, SA, Australia.

MEASUREMENTS

HPA activity was assessed from the serum cortisol 30 min after 1 µg ACTH_1-24 (Novartis Pharmaceuticals). Subjects with a cortisol below (n = 15) and above (n = 15) the median were categorized as low and high responders, respectively. Reactive hyperaemia index (RHI) was measured fasting to estimate endothelial function. Matsuda index was calculated from glucose and insulin concentrations collected fasting and 30 minutely for 2 h after a mixed meal (10 kcal/kg, 45% carbohydrate, 15% protein, 40% fat). The primary endpoint was the difference in RHI between low and high responders.

RESULTS

There were no significant differences in age (61 ± 9 vs. 64 ± 7 years, p = .19), body mass index (BMI; 26 ± 3 vs. 24 ± 4 kg/m² , p = .25) and sex (p = .71) between low and high responders. High responders had a lower RHI (2.1 ± 0.2 vs. 2.6 ± 0.2, p = .04) than low responders and there was a negative association between RHI and peak cortisol post ACTH_1-24 (β = -.56, p < .01). There were no significant differences in Matsuda index (15.0 ± 2.4 vs. 22.7 ± 5.2, p = .19) between high and low responders.

CONCLUSION

In healthy adults, endothelial dysfunction is likely to contribute to the association between HPA hyperactivity and increased cardiovascular risk. As insulin sensitivity was not different in high and low responders, endothelial dysfunction is not primarily secondary to insulin resistance.

Dysregulated diurnal cortisol patterns are associated with cardiovascular mortality: Findings from the KORA-F3 study

Psychosocial stress has been associated with an increased risk for cardiovascular disease and death. Dysregulated diurnal cortisol slopes, which have also been associated with stress, might mediate this association. However, existing evidence on the cardiovascular health consequences of dysregulated cortisol slopes remains limited and inconclusive. To elucidate whether dysregulated diurnal cortisol slopes are related to cardiovascular mortality, we assessed salivary cortisol and cardiovascular morbidity and mortality in 1090 participants from the KORA-F3 study, a prospective, observational cohort study of a random representative sample from the general population. Eighty-seven deaths were registered during the mean follow-up period of approximately 11 years, 31 of which were classified as cardiovascular deaths. A more pronounced cortisol awakening response was associated with a lower risk of cardiovascular mortality in the adjusted Cox proportional hazards analysis (HR 0.59 [95-%-CI 0.36-0.96], p = 0.03). A greater diurnal cortisol peak-to-bedtime ratio at baseline also predicted a decreased risk of cardiovascular mortality (HR 0.50 [95-%-CI 0.34-0.73], p 0.01) and a decreased risk of stroke (HR 0.71 [95-%-CI 0.55-0.92], p 0.01). Increased levels of late night salivary cortisol predicted a higher risk of cardiovascular mortality (HR 1.49 [95-%-CI 1.13-1.97], p 0.01) and an increased risk of stroke (HR 1.24 [95-%-CI 1.01-1.52], p = 0.04). There was no association between measures of cortisol and non-cardiovascular related mortality. In conclusion, dysregulated diurnal cortisol patterns are associated with cardiovascular mortality, while greater diurnal cortisol variation seems to have a protective effect. This adds evidence to suggest a pathophysiological role of diurnal cortisol secretion patterns in cardiovascular health.

Study protocol for measuring the impact of (quasi-)monochromatic light on post-awakening cortisol secretion under controlled laboratory conditions

Cortisol secretion has a fundamental role in human circadian regulation. The cortisol awakening response (CAR) can be observed as a daily recurring sharp increase in cortisol concentration within the first hour after awakening and is influenced by environmental light conditions. The current work provides the study protocol for an ongoing research project that is intended to explore the spectral dependencies and to discuss measures of emotional state and cognitive functioning potentially related to the CAR. Based on a controlled within-subjects sleep laboratory study, the impact of a two-hour, (quasi-)monochromatic, post-awakening light exposure of different peak wavelength (applied from 6:00 to 8:00 am) on resulting CAR levels should be investigated in a systematic manner to eventually derive a corresponding spectral sensitivity model. As a secondary outcome, it should be explored whether a potentially light-enhanced cortisol secretion might also impact different measures of sleepiness, mood, and vigilance for certain wavelengths. The study protocol described in the present work discusses the various protocol steps using pilot data collected for two different wavelength settings (i.e., short-wavelength blue-light at λmax = 476 nm and long-wavelength red-light at λmax = 649 nm) experienced by a group of four healthy male adults at an average ± SD age of 25.25 ± 3.59 years.

Lack of Evidence for a Relationship Between Salivary CRP and Women's Sexual Desire: An Investigation Across Clinical and Healthy Samples

BACKGROUND

Inflammation has been linked to a variety of mental and physical health outcomes that disproportionately impact women, and which can impair sexual function; thus, there is reason to expect a link between inflammation and women's sexual functioning.

AIM

To test the hypothesis that higher concentrations of C-reactive protein (CRP), a general biomarker of inflammation, would predict women's lower sexual desire.

METHOD

As 2 independent research teams, we conducted 3 separate studies (total n = 405) that assessed salivary CRP and various measurements of sexual desire in different women populations.

OUTCOMES

Female Sexual Function Index, Sexual Desire Inventory-2, Decreased Sexual Desire Screener, and Sexual Interest and Desire Inventory.

RESULTS

Regardless of the way sexual desire was measured (e.g., state vs trait; general desire vs. desire functioning) and the population sampled (i.e., healthy vs. clinically diagnosed with sexual dysfunction), all the studies revealed null results.

CLINICAL IMPLICATIONS

While exploratory, the convergence of these null results across studies and researchers suggests that if there is an association between inflammation and women's sexual desire, it is likely very subtle.

STRENGTHS & LIMITATIONS

Across 2 independent research teams, 3 unrelated studies, and various measurements of sexual desire, results were consistent. These points lend to the generalizability of the results. However, study designs were cross-sectional.

CONCLUSIONS

Future research may reveal (i) a non-linear threshold effect, such that inflammation does not begin to impact women's sexual desire until it is at a high level, (ii) inflammatory biomarkers other than CRP might be more sensitive in detecting associations between inflammation and desire, should they exist, or (iii) the mechanisms underlying sexual dysfunction may differ between sexes. Clephane K, et al. Lack of Evidence for a Relationship Between Salivary CRP and Women's Sexual Desire: An Investigation Across Clinical and Healthy Samples. J Sex Med 2022;19:745-760.

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.

Cognitive behavioral therapy versus general health education for family caregivers of individuals with heart failure: a pilot randomized controlled trial

Background

While support from family caregivers is essential in the care of patients with heart failure (HF), caregiving places a considerable burden on family caregivers. We examined the preliminary effects of cognitive behavioral therapy (CBT) for caregivers of individuals with HF.

Methods

In this pilot randomized controlled trial, patients with HF and their primary family caregivers (30 dyads) were randomized into CBT (n = 15) or general health education (GHE, n = 15) groups. Caregivers received 8 weekly individual sessions of either CBT (intervention) or GHE (attention control condition). Caregivers completed questionnaires at baseline, post-intervention, and 6 months. Saliva samples collected from caregivers at baseline and post-intervention were analyzed for salivary cortisol. The cortisol awakening response (CAR) and area under the curve (AUC) were calculated using log-transformed cortisol values. We analyzed data from 26 (14 receiving CBT and 12 receiving GHE) caregivers who received at least one session of CBT or GHE (modified intention-to treat) using linear mixed models. Each model included time, study group, and time-by-study group interaction as fixed effects.

Results

Patients were older (66.94 ± 14.01 years) than caregivers (55.09 ± 15.24 years), and 54% of patients and 54% of caregivers were female. Most caregivers (58%) were spouses. A total of 14 (93%) CBT and 12 (80%) GHE participants received at least 1 session (p = .60), and 11 (73%) CBT and 11 (73%) GHE participants completed all 8 sessions (p = 1.00). There were no significant between-group differences in change for salivary cortisol or psychological outcomes. However, the CBT group had significant within-group improvements in perceived stress (p = .011), stress symptoms (p = .017), depression (p = .002), and anxiety (p = .006) from baseline to post-intervention, while the control group had no significant within-group change in the outcomes except for anxiety (p = .03). The significant improvements observed in the CBT group lasted for 6 months. No adverse effects were observed.

Conclusions

In this pilot trial, although between-group differences in change were not significant, CBT resulted in significant improvements in some psychological outcomes with no improvement in the control group. Our findings suggest the potential of the intervention to alleviate psychological distress in HF caregivers. Further examination in larger randomized trials is warranted.

Trial registration

ClinicalTrials.gov Identifier: NCT01937936 (Registered on 10/09/2013).

ASSOCIATION BETWEEN ALTERED CORTISOL PROFILES AND NEUROBEHAVIORAL IMPAIRMENT FOLLOWING mTBI IN COLLEGE STUDENTS

Mild Traumatic Brain Injury (mTBI) is the most common form of TBI, accounting for over 2.5 million TBI cases in the United States annually. Identification of easily obtainable biomarkers that track strongly with mTBI symptoms may improve our understanding of biological factors that contribute to mTBI symptom profiles and long-term outcomes. Notably, some individuals with mTBI exhibit circadian disruptions and elevated stress sensitivity, which in other clinical groups often correlate with disrupted secretion of cortisol, a glucocorticoid hormone that coordinates circadian and stress physiology. Here, we sought to determine whether cortisol profiles could serve as a biomarker to complement the assessment of neurobehavioral sequelae following mTBI. We partnered with our on-campus health clinic to recruit college students seeking medical care following mTBI (n=46) and compared this population to a well-matched non-injured student control group (n=44). We collected data at an initial visit (shortly after injury in mTBI subjects) and one week later. At each visit, we evaluated neurobehavioral function using the Automated Neuropsychological Assessment Metric (ANAM). Our subjects then provided cortisol samples through at-home saliva collection. We observed strong coherence between ANAM subjective and objective measures, indicating significant multidimensional impairment in those with mTBI. Further, female mTBI subjects exhibited diminished neurobehavioral function compared to males. Regardless of sex, decreased amplitude of diurnal cortisol and a blunted cortisol awakening response predicted mTBI symptom severity and neurobehavioral impairment. Taken together, these findings suggest that salivary cortisol profiles may be a sensitive biomarker for studying underlying biological factors that impact mTBI outcomes.

Salivary Biomarkers (Opiorphin, Cortisol, Amylase, and IgA) Related to Age, Sex, and Stress Perception in a Prospective Cohort of Healthy Schoolchildren

Background

The use of easily accessible biomarkers for assessing young patients' health is weighty. This cohort study is aimed at measuring stress/immune biomarkers in the saliva of healthy school-age children and comparing subgroups according to age, sex, and stress perception. Material and Methods. 503 children under 12 years old (8.7 ± 1.3) were included with anthropometric evaluation (height, waist, hip circumference, body weight, and body mass index (BMI)). Levels of opiorphin (OPI), free cortisol, alpha-amylase (sAA), and secreted immunoglobulin (sIgA) were determined by quantitative assays (ELISA) in unstimulated saliva. Unpaired t-test, Welch test, and Mann-Whitney U test were applied for appropriate group comparisons, and the correlation between variables was analyzed with Spearman's rank coefficient. Results were considered significant at p < 0.05.

Results

sIgA and sAA exhibited significant differences depending on age and sex: IgA (ng/mL): 86 ± 68.6 vs. 104.9 ± 72.1 for (6-7 y.o.) and (8-11 y.o.), respectively, and 108.1 ± 80.1 vs. 94.6 ± 62.2 for male and females, respectively; sAA (U/mL): 78.9 ± 54.4 vs. 100.5 ± 81.2 for (6-7 y.o.) and (8-11 y.o.). No difference related to age or sex between groups was observed for cortisol and OPI. However, OPI levels were higher and correlated to prior stress exposure in children (0.31 ± 0.4 vs. 0.26 ± 0.5 ng/mL, p = 0.031). sAA was negatively correlated to low mood self-declaration in children in the last two weeks (r = -0.10, p = 0.045).

Conclusions

sIgA and sAA can be used as sex- and age-related biomarkers in children 6-12 y.o., which is not the case for free cortisol and opiorphin. However, OPI reflected previous exposure to stress, suggesting its use for evaluating stress-related changes in children.

Eight Weeks of Lifestyle Change: What are the Effects of the Healthy Lifestyle Community Programme (Cohort 1) on Cortisol Awakening Response (CAR) and Perceived Stress?

Background: Stress and cortisol dysregulation are linked to NCDs. Moreover, stress favours unhealthy lifestyle patterns, which increase the risk for NCDs. The role of the Cortisol Awakening Response (CAR) and the effect of lifestyle interventions on the same remain unclear. Methods: The impact of the intensive 8-week phase of the Healthy Lifestyle Community Programme (HLCP, cohort 1) on parameters of the CAR, ie cortisol values 0 (sample [S]1), 30), 45 and 60 minutes post-awakening, average peak, S1-peak delta and area under the increase curve (AUCI), and perceived stress levels (PSL) was evaluated in a non-randomized, controlled trial. Covariates of the CAR (eg sleep measures) and irregularities in sampling were assessed. The intervention focussed on stress management, a healthy diet, regular exercise, and social support. Participants were recruited from the general population. Multiple linear regression analyses were conducted. Results: 97 participants (age: 56 ± 10 years; 71% female), with 68 in the intervention group (IG; age: 55 ± 8, 77% female) and 29 participants in the control group (CG; age: 59 ± 12, 59% female), were included in the analysis. The baseline characteristics of both groups were comparable, except participants of IG were younger. On average, the PSL at baseline was low in both groups (IG: 9.7 ± 5.4 points; CG: 8.5 ± 6.9 points; p = .165), but 22% (n = 15) in the IG and 20% (n = 6) in the CG reported a high PSL. Most participants reported irregularities in CAR sampling, eg interruption of sleep (IG: 80% CG: 81%). After 8 weeks, most CAR parameters and the PSL decreased in the IG and CG, resulting in no differences of change between the groups. In the IG only, a decrease of PSL was linked to an increase of CAR parameters, eg AUCI (correlation coefficient = −0.307; p = .017). Conclusion: The HLCP may potentially reduce PSL and change the CAR, but results cannot be clearly attributed to the programme. Methodological challenges and multiple confounders, limit suitability of the CAR in the context of lifestyle interventions. Other measures (eg hair-cortisol) may give further insights. Trial registration: German Clinical Trials Register (DRKS); DRKS00018821; www.drks.de

Psychophysiological adjustment to formal education varies as a function of peer status and socioeconomic status in children beginning kindergarten

The transition to kindergarten can be stressful as children adjust to novel separations from their caregivers and become accustomed to their peer group. A 9-month study of 96 children (M_age  = 5.37 years, SD = 0.42) from Barranquilla, Colombia, assessed socioeconomic differences in hypothalamic-pituitary-adrenal (HPA) axis functioning across the kindergarten year. Children were from four different classrooms in one school. Saliva samples were collected twice a day across 3 consecutive days at the beginning and end of the school year. We examined whether change in HPA axis activation across the year varied as a function of a child's socioeconomic status (SES) and experience in the peer group. We found that rejected children and lower SES children had lower cortisol levels early in the morning. Rejected children had a flatter morning cortisol slope. Lower SES children had higher cortisol than their higher SES peers at the end of the school year and a flatter morning cortisol slope. Taken together, these findings suggest that diurnal cortisol in children beginning kindergarten may be influenced by both peer rejection and SES.

Work e-mail after hours and off-job duration and their association with psychological detachment, actigraphic sleep, and saliva cortisol: A 1-month observational study for information technology employees

Objective

A sufficient duration of time off after work is necessary to ensure workers’ health. Better quality of off‐job time can also facilitate recovery from fatigue, but its quantitative influence is largely unknown. We aimed to examine how off‐job time quality (as measured by the frequency of emailing after work), and off‐job duration is associated with psychological detachment, actigraphic sleep, and saliva cortisol using a 1‐month observational study.

Methods

The participants were 58 daytime employees working at an information technology company. Sleep actigraphy and saliva cortisol as well as self‐reported outcomes were repeatedly measured for 1 month. Two‐way (work e‐mail frequency × off‐job time) multilevel mixed‐effects linear regression analyses were performed in both continuous and categorical variables.

Results

The frequency of work e‐mailing after hours was significantly associated with self‐reported outcomes and actigraphic sleep quality, while a significant association was not found in cortisol awakening responses and actigraphic sleep duration. A significantly larger cortisol response after awakening was found in shorter, rather than longer, durations of off‐job time. Self‐reported detachment, rumination and carry‐over fatigue showed significant interactions between work e‐mail and off‐job time, suggesting that worse outcomes were found in a higher frequency of work e‐mail even when employees had longer amounts of off‐job time.

Conclusion

Our findings suggest that ensuring the quality and duration of off‐job time is beneficial for recovery from work with sufficient sleep. Specifically, the frequency of e‐mailing after work should be minimized to make recovery complete.