Cortisol awakening rise in middle-aged women in relation to psychological stress

Effects of the healthy lifestyle community program (cohort 1) on stress-eating and weight change after 8 weeks: a controlled study

Stress-eating (eating more or more unhealthily in order to accommodate to stress), contributes to the development and maintenance of obesity. The effect of comprehensive weight loss interventions on changes in stress-eating as well as the contributing role of stress-eating on weight reduction has not been examined. The impact of the 8-week intensive phase of the Healthy Lifestyle Community Programme (HLCP, cohort 1) on emotional, external and restrained eating, as expressions of stress-eating was evaluated in a non-randomized controlled trial. Intervention: 14 seminars (twice per week, including practical units), complemented by stress-regulation and cooking workshops and coaching sessions empowering participants to change their behaviour towards a healthy plant-based diet (ad libitum), stress regulation, regular exercise and to focus on social support. Participants were recruited from the general population. In the intervention group, 91 participants (IG; age: 56 ± 10, 77% female) and in the control group, 52 (CG; age: 62 ± 14, 57% female) were enrolled. At baseline, participants of the IG reported higher levels of stress (9.7 ± 5.4 points [P] vs. 7.6 ± 6.2; p < 0.011), and of emotional eating (27.9 ± 9.4 vs. 20.0 ± 7.1; p < 0.001) and external eating (29.1 ± 4.9 vs. 25.5 ± 5.6; p < 0.001) than participants of the CG. Within 8 weeks, in the IG, scores of emotional eating (- 3.5 ± 5.4 P) and external eating significantly decreased (= - 2.0 ± 3.8 P), while restrained eating increased (2.7 ± 5.0 P; p for all < 0.001). Weight change was negatively correlated with change of external eating (R² = 0.045; CC = - 0.285; p = 0.014), indicating that a greater weight change was associated with a smaller change of external eating. This is the first study to prospectively investigate the role of stress-eating on the weight reduction effect of comprehensive lifestyle interventions. Our data confirm that overweight is associated with EE and external eating and suggest that the HLCP is capable to reduce both, weight and stress-eating.Trial registration: German Clinical Trials Register (DRKS; reference: DRKS00018821; September 18th 2019; retrospectively registered).

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.

Salivary cortisol levels and appraisals of daily hassles across dimensions of the tripartite model of anxiety and depression in emerging adults

The objective of this study was to investigate how cortisol levels and appraisals of daily hassles differ across tripartite dimensions of depression and anxiety in emerging adults. Data collected from a sample of undergraduate students at a large Midwestern university was used to investigate these aims. This included salivary cortisol data collected over four days, scores on a measure of the tripartite model of anxiety and depression, and scores on a measure of daily hassles administered everyday for two weeks. Generalized estimating equations and multilevel modeling techniques were used to analyze data. Elevated cortisol levels during the awakening period and the evening period, lower total levels across the day, steeper diurnal slopes, and elevated levels of negative affect and physiological hyperarousal predicted experiences of daily hassles. Tripartite dimensions were unrelated to cortisol indices. The present study demonstrates the utility of modeling multiple cortisol indices and provides evidence of differential associations between physiological and phenomenological indices of stress.

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.

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.

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

Associations of perceived stress and salivary cortisol with the snack and fast-food dietary pattern in women shift workers

This study aimed to investigate the association of perceived stress and salivary cortisol levels with the snack and fast-food dietary pattern in a sample of women shift workers. We conducted a cross-sectional study of 539 women aged 18-53 years working in the production line of a poultry processing plant. Stress was assessed with the 10-item Perceived Stress Scale (PSS-10) and by salivary cortisol levels (immediately after waking and upon returning home from work). Dietary patterns were identified by principal component analysis. We used linear and Poisson regression models to assess multivariable-adjusted associations of perceived stress and salivary cortisol levels with the snack and fast-food dietary pattern. After adjustments, women with higher PSS-10 scores had a 28% higher probability (95% confidence interval, 1.04-1.56) of consuming snacks/fast food. Mean (SD) waking cortisol levels were inversely associated with quartiles of the dietary pattern: Q1, 6.63 (0.43) nmol/L; Q2, 6.00 (0.38) nmol/L; Q3, 5.62 (0.40) nmol/L; and Q4, 5.29 (0.35) nmol/L (p = 0.019). Perceived stress was not associated with salivary cortisol levels. The work shift was not associated with perceived stress or cortisol levels. This study demonstrated an association of psychological and physiological measures of stress with a dietary pattern characterized by high intakes of hyper-palatable, energy-dense, ready-to-eat foods among women shift workers.

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.

Exploring the effects of daily hassles and uplifts on eating behaviour in young adults: The role of daily cortisol levels

Existing stress-eating research has shown that daily hassles are associated with increases in food intake and that cortisol reactivity to stress has been found to influence the stress-eating relationship. However, the moderating effects of daily cortisol levels (e.g., the cortisol awakening response, CAR) remain unknown. Moreover, recent evidence has shown that daily uplifts, as well as daily hassles, are important in understanding daily influences on eating behaviour. Therefore, in the same study, the current investigation explored the effects of daily hassles and uplifts on eating behaviour and whether these relationships were moderated by mean daily cortisol levels in young female adults. Forty-nine female participants (M age: 19.13 years) recorded the daily hassles and uplifts that they experienced over a 4-day period, together with the between-meal snacks they consumed each day, using an online daily diary. Cortisol samples were provided daily immediately upon waking, at +30 min and +12 h. Mean CAR and mean cortisol levels were calculated across the 4 days. Using multi-level modeling, daily hassles and uplifts were both significantly associated with greater unhealthy snacking. Daily uplifts, but not daily hassles, were also associated with lower healthy snack intake. Higher levels of mean CAR were associated with lower daily healthy snack intake. Moreover, the effects of daily uplifts on healthy snacking were found to be moderated by mean daily cortisol levels, such that participants with the highest levels of mean cortisol consumed less healthy snacks on days when they experienced uplifts. The current study provides novel evidence that mean daily cortisol levels, as well as daily hassles and uplifts, are implicated in daily snack consumption in young female adults. The role of hypothalamic-pituitary adrenal axis activity should be explored further in the context of the daily hassles/uplifts and eating behaviours relationship, in men and in individuals from lower socio-economic status and minority groups.

Diurnal cortisol secretion and health-related quality of life in healthy older people

Several studies have demonstrated that a dysregulated hypothalamic-pituitary-adrenal (HPA) axis is related to worse health status (e.g., depression, posttraumatic stress, or diabetes, among others). However, less is known about the association between the individual's perception of their own health status and HPA-axis functioning in healthy older people. The aim of the present study was to examine the relationship between HPA-axis functioning and health-related quality of life (HRQoL) in healthy older people. To do this, 140 healthy older people (69 men and 71 women) from 56 to 76 years old collected eight saliva samples on two consecutive weekdays to measure the diurnal cortisol cycle (i.e. awakening cortisol levels, cortisol awakening response (CAR), overall morning cortisol levels, change in the cortisol levels during the day, and bedtime cortisol levels). In addition, they completed the SF-36 questionnaire to obtain a measure of HRQoL (i.e. reflecting physical and mental functional health status). Results showed that higher awakening and bedtime cortisol levels and the CAR were associated with a better perception of both physical and mental health. In addition, the wake-to-bed cortisol slope was only positively related to physical health. No sex differences were found. These findings suggest that the awakening and bedtime cortisol levels and the CAR are the most relevant indices of diurnal cortisol secretion for understanding the relationship between HPA-axis functioning and HRQoL status in older people.

Differential Susceptibility to the Impact of the COVID-19 Pandemic on Working Memory, Empathy, and Perceived Stress: The Role of Cortisol and Resilience

There are important individual differences in adaptation and reactivity to stressful challenges. Being subjected to strict social confinement is a distressful psychological experience leading to reduced emotional well-being, but it is not known how it can affect the cognitive and empathic tendencies of different individuals. Cortisol, a key glucocorticoid in humans, is a strong modulator of brain function, behavior, and cognition, and the diurnal cortisol rhythm has been postulated to interact with environmental stressors to predict stress adaptation. The present study investigates in 45 young adults (21.09 years old, SD = 6.42) whether pre-pandemic diurnal cortisol indices, overall diurnal cortisol secretion (AUCg) and cortisol awakening response (CAR) can predict individuals' differential susceptibility to the impact of strict social confinement during the Coronavirus Disease 2019 (COVID-19) pandemic on working memory, empathy, and perceived stress. We observed that, following long-term home confinement, there was an increase in subjects' perceived stress and cognitive empathy scores, as well as an improvement in visuospatial working memory. Moreover, during confinement, resilient coping moderated the relationship between perceived stress scores and pre-pandemic AUCg and CAR. In addition, in mediation models, we observed a direct effect of AUCg and an indirect effect of both CAR and AUCg, on change in perceived self-efficacy. These effects were parallelly mediated by the increase in working memory span and cognitive empathy. In summary, our findings reveal the role of the diurnal pattern of cortisol in predicting the emotional impact of the COVID-19 pandemic, highlighting a potential biomarker for the identification of at-risk groups following public health crises.

"It made me feel brighter in myself"- The health and well-being impacts of a residential front garden horticultural intervention

Residential gardens make up 30% of urban space in the UK, yet unlike many other green space typologies, their role in the health and well-being agenda has largely been overlooked. A horticultural intervention introduced ornamental plants to 38 previously bare front gardens (≈ 10 m²) within an economically deprived region of North England, UK. Measures of perceived stress and diurnal cortisol profiles (as an indicator of health status) were taken pre- and post-intervention (over 3 months). Residents reported significant decreases in perceived stress post-intervention. This finding was aligned with a higher proportion of 'healthy' diurnal cortisol patterns post-intervention, suggesting better health status in those individuals. All residents derived one or more reported socio-cultural benefits as a result of the front garden plantings, although overall scores for subjective well-being did not increase to a significant level. Further qualitative data suggested that the gardens were valued for enhancing relaxation, increasing positive emotions, motivation, and pride of place. The results indicate that adding even small quantities of ornamental plants to front gardens within deprived urban communities had a positive effect on an individual's stress regulation and some, but not all, aspects of subjective well-being. The research highlights the importance of residential front gardens to human health and well-being, and thus their contribution to the wider debates around city densification, natural capital and urban planning.

Serum Lipid Concentrations Are Associated With Negative Mental Health Outcomes in Healthy Women Aged 35-49 Years

Background: Although the relevant underlying biological mechanisms are still lacking, mental disorders have been closely associated with several metabolic abnormalities including high rates of obesity and metabolic syndrome especially in vulnerable populations. Therefore, the current study aims to examine how metabolic parameters increase the risk for developing mood disorders in individuals stratified by gender and age. Methods: In a routine physical examination, 319 healthy participants were recruited and assigned to six different groups according to age (young adults: 25-34 Y, middle age: 35-49 Y, and older age: 50-65 Y) in both males and females. A linear regression and bivariate correlation analysis were used to analyze the relationship between mood health outcomes measured by the Kessler 10 Psychological Distress Scale (K10) and the metabolic function. Results: The results demonstrated that there was a significant association between K10 scores and metabolic parameters, including Body Mass Index (BMI), total-, LDL-cholesterol, and triglyceride. Furthermore, poor mental health (higher K10 scores) was observed in individuals with increased BMI, total-, LDL-cholesterol, and triglyceride levels particularly in middle-aged women relative to other groups. Limitations: This is a cross-sectional study with a small sample size and lacks longitudinal follow-up evidence and preventive interventions and therefore could not provide the causal inference of metabolic pathophysiology on the increased sensitivity to mental disorders. Conclusions: The potential association suggests that targeting of the metabolic parameters might give us a better understanding of the underlying mechanisms of psychiatric diseases and provide preventive strategies and potential treatment for those with metabolic disturbances especially in middle-aged females.

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.

Stress, the cortisol awakening response and cognitive function

There is evidence that stress-induced disruption of the circadian rhythm of cortisol secretion, has negative consequences for brain health. The cortisol awakening response (CAR) is the most prominent and dynamic aspect of this rhythm. It has complex regulatory mechanisms making it distinct from the rest of the cortisol circadian rhythm, and is frequently investigated as a biomarker of stress and potential intermediary between stress and impaired brain function. Despite this, the precise function of the CAR within the healthy cortisol circadian rhythm remains poorly understood. Cortisol is a powerful hormone known to influence cognition in multiple and complex ways. Studies of the CAR and cognitive function have used varied methodological approaches which have produced similarly varied findings. The present review considers the accumulating evidence linking stress, attenuation of the CAR and reduced cognitive function, and seeks to contextualize the many findings to study populations, cognitive measures, and CAR methodologies employed. Associations between the CAR and both memory and executive functions are discussed in relation to its potential role as a neuroendocrine time of day signal that synchronizes peripheral clocks throughout the brain to enable optimum function, and recommendations for future research are provided.

Stress, cortisol and suicide risk

Suicide is a global health issue accounting for at least 800,000 deaths per annum. Numerous models have been proposed that differ in their emphasis on the role of psychological, social, psychiatric and neurobiological factors in explaining suicide risk. Central to many models is a stress-diathesis component which states that suicidal behavior is the result of an interaction between acutely stressful events and a susceptibility to suicidal behavior (a diathesis). This article presents an overview of studies that demonstrate that stress and dysregulated hypothalamic-pituitary-adrenal (HPA) axis activity, as measured by cortisol levels, are important additional risk factors for suicide. Evidence for other putative stress-related suicide risk factors including childhood trauma, impaired executive function, impulsivity and disrupted sleep are considered together with the impact of family history of suicide, perinatal and epigenetic influences on suicide risk.

Stressful Factors in the Working Environment, Lack of Adequate Sleep, and Musculoskeletal Pain among Nursing Unit Managers

Background: Middle managers have not received enough attention within the healthcare field, and little is known how stressful factors in their work environment coupled with a lack of adequate sleep are related to musculoskeletal pain. The aim of this study was to examine the correlation between stressful factors in the work environment, lack of adequate sleep, and pain/discomfort in three body areas. Methods: Questionnaire was sent electronically to all female nursing unit managers (NUM) in Iceland through the outcome-survey system. The response rate was 80.9%. Results: NUM who had high pain/discomfort in the neck area also had very high pain/discomfort in the shoulder area and pain in the lower back. The results also revealed positive a medium-strong correlation between mental and physical exhaustion at the end of the workday and musculoskeletal pain. Stress in daily work, mental strain at work, and being under time-pressures had hardly any correlation with pain/discomfort in the three body parts. Adequate sleep had a significant negative correlation with all stressful factors in the work environment and all three body parts under review. Conclusion: The results will hopefully lead to a better consideration of stressful factors in the work environment, sleep, and musculoskeletal pain in middle managers.

Salience versus magnitude in the measurement of the cortisol awakening response

Pulsatile ultradian secretion of cortisol, rarely studied in salivary data, has functional importance in hypothalamic pituitary adrenal (HPA) axis regulation. The first daily ultradian episode, the cortisol awakening response (CAR), was examined in healthy adults, in 5-min secretion rates of salivary cortisol from electronically monitored awakening time to 1.25 h. Aggregated rates revealed a cubic trend, with wave-length of almost exactly 1 h, as predicted from known ultradian periodicity. Peak secretion rate occurred 20-min post-awakening. Peak (20-min) to trough (59-min) amplitude (PTA) expressed a salient signal shape. Rates rose steeply to and from peak, and major secretion was packaged into a few 5-min intervals, inconsistent with normal or uniform distribution of 5-min rates, but consistent with known pulsatile cortisol delivery. Null hypotheses asserting normal or uniform distributions were rejected. Maximal rates overwhelmingly occurred before and minimal rates after 30-mins, with degree of extremity at each polarity significantly positively correlated. To demonstrate utility and reliability of PTA estimation in a clinically relevant domain, re- analyses of a previously published study were conducted. Data from only three saliva samples were used, given importance of cost considerations for many CAR researchers. Difference between mean rates before and after 30-min yielded a simple salience index, highly correlated with PTA derived from full 5-min interval data. CAR salience performed significantly better than traditional AUCi magnitude in discriminating control cases (higher inferred amplitude) and cases with Seasonal Affective Disorder (lower inferred amplitude). Evidence suggested that low AUCi may be more sensitive in identifying within-subject changes (e.g. more depressed mood in winter among SAD cases) and low CAR salience better at revealing enduring between-subjects associations (e.g. underlying disorder vulnerability). Since both PTA salience and AUCi magnitude can be analysed and compared using exactly the same data from the same commonly used saliva sampling points, further research is warranted into the importance of individual differences in patterns of cortisol delivery, not just how much is delivered.

Patients with atopy exhibit reduced cortisol awakening response but not cortisol concentrations during the rest of the day

It has been documented that cortisol release in response to acute stressors is reduced in patients with atopic dermatitis, allergic rhinitis, and other atopic diseases compared to that in healthy subjects. We aimed to test the hypothesis that atopic patients exert reduced salivary cortisol awakening response (CAR) in comparison with healthy subjects. The hypothesis was tested on a stressful and a relax day selected subjectively. Moreover, we evaluated the impact of trait anxiety. The sample consisted of 60 subjects, out of which 28 were patients with atopy and 32 healthy volunteers of both sexes. Saliva samples were collected in the morning to evaluate CAR as well as in the early afternoon and evening to look at cortisol concentrations during the rest of the day. The results showed reduced CAR in atopic patients compared to that in healthy subjects. This effect was modulated by sex with a significant difference observed in males. While CAR was reduced, atopic patients had unchanged cortisol concentrations throughout the day. The evening cortisol was even higher in atopic patients. If the subjects were stratified according to the trait anxiety, no significant differences in CAR between high and low anxiety were observed. No differences in cortisol variables including CAR were observed between the stressful and relax day. In conclusion, this study presents evidence on reduced CAR suggesting an insufficient HPA axis reactivity in atopy. Furthermore, the data in atopic patients demonstrate that reduced HPA axis reactivity does not necessarily mean lower cortisol concentrations throughout the day. This might be of relevance to immune system function and the course of the disease.

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

BACKGROUND

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The cortisol awakening response predicts response inhibition in the afternoon of the same day

The cortisol awakening response (CAR) is the rapid increase of cortisol levels 30-45 min after awakening in the morning. Numerous studies have indicated the relationship between the CAR and cognition. However, little is known about daily variation in the CAR and cognitive function in healthy adults. The aim of the present study was to investigate whether the CAR predicted the response inhibition function on the same day in both behaviour and the dynamic time course of brain processing. The saliva samples of 47 healthy men were collected at three time points: immediately on awakening, 30 min and 45 min post-awakening in the morning. Participants performed a Go/NoGo task while electroencephalograms (EEG) were recorded in the afternoon of the same day. The results showed that a greater CAR was associated with a stronger N2. In the sub-group of CAR responders (n = 33) the CAR was negatively related to the false alarm rate of NoGo-trials. Our findings suggested that the CAR was predictive of the function of response inhibition in both the earlier cognitive step (i.e., conflict monitoring) and the behavioural performance of response inhibition on the same day in healthy men.

Effects of childhood trauma on cortisol levels in suicide attempters and ideators

OBJECTIVES

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 for suicide. Recent evidence has indicated that blunted cortisol reactivity to stress is associated with suicidal behavior. The current study investigated whether childhood trauma was associated with blunted cortisol reactivity to a laboratory stressor and resting cortisol levels in suicide attempters and ideators.

METHODS

160 Participants were recruited and grouped according to history of previous suicidal attempt, suicidal ideation or as control participants. Participants completed background questionnaires, including the Childhood Trauma Questionnaire, before completing a laboratory stress task. Cortisol levels were assessed at rest and during the stress task.

RESULTS

The highest levels of childhood trauma were reported in those who had attempted suicide (78.7%), followed by those who thought about suicide (37.7%) and then those with no suicidal history (17.8%). Moreover, regression analyses showed that childhood trauma was a significant predictor of blunted cortisol reactivity to stress and resting cortisol levels, such that higher levels of trauma were associated with lower cortisol levels in those with a suicidal history. Family history of suicide did not interact with the effects of childhood trauma on cortisol levels.

CONCLUSIONS

These results indicate that childhood trauma is associated with blunted HPA axis activity in vulnerable populations in adulthood. The challenge for researchers is to elucidate the precise causal mechanisms linking trauma, cortisol and suicide risk and to investigate whether the effects of childhood trauma on cortisol levels are amendable to psychological intervention.

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

Cortisol levels rise immediately after awakening and peak approximately 30-45min thereafter. Psychosocial functioning influences this cortisol awakening response (CAR), but there is considerable heterogeneity in the literature. The current study used p-curve and meta-analysis on 709 findings from 212 studies to test the evidential value and estimate effect sizes of four sets of findings: those associating worse psychosocial functioning with higher or lower cortisol increase relative to the waking period (CARi) and to the output of the waking period (AUCw). All four sets of findings demonstrated evidential value. Psychosocial predictors explained 1%-3.6% of variance in CARi and AUCw responses. Based on these effect sizes, cross-sectional studies assessing CAR would need a minimum sample size of 617-783 to detect true effects with 80% power. Depression was linked to higher AUCw and posttraumatic stress to lower AUCw, whereas inconclusive results were obtained for predictor-specific effects on CARi. Suggestions for future CAR research are discussed.

Prolonged perceived stress and saliva cortisol in a large cohort of Danish public service employees: cross-sectional and longitudinal associations

Purpose

It is well known that acute stress can lead to a transient increase in cortisol secretion, but the effects of prolonged stress on cortisol secretion are uncertain. This study examines the cross-sectional and longitudinal associations between prolonged perceived stress and salivary cortisol.

Methods

In 2007, 4467 Danish public service employees participated in a study of stress and mental health, and 3217 participated in a follow-up in 2009. Perceived stress during the past 4 weeks was assessed by Cohen’s four item perceived stress scale. Participants were asked to collect saliva 30 min after awakening and at approximately 20:00 in the evening. The cortisol dependence on perceived stress was examined in regression analyses adjusted for effects of potential confounders. We adjusted for a large variation in saliva sampling times by modelling the time trajectory of cortisol concentrations in the morning and in the evening and examined if they were influenced by perceived stress.

Results

Perceived stress had no statistically significant effects on the level or time trajectory of morning or evening cortisol, neither cross-sectionally nor longitudinally. The 1 month prevalence of frequently perceived stress was low, approximately 2.5%.

Conclusion

Our results did not support the hypothesis that prolonged perceived stress is associated with the level or time trajectory of morning or evening salivary cortisol.

Electronic supplementary material

The online version of this article (doi:10.1007/s00420-017-1241-z) contains supplementary material, which is available to authorized users.

Impact of psychological health on peripheral endothelial function and the HPA-axis activity in healthy adolescents

BACKGROUND AND AIMS

The development of adolescence psychological health over a 3-year period and its relationship to peripheral endothelial function and the hypothalamic-pituitary-adrenal (HPA)-axis activity were examined in a cohort of healthy adolescents in a longitudinal study.

METHODS

A total of 162 adolescents (94 females) participated in both baseline (mean age 14.5 ± 1 years) and three-year follow-up studies. Psychological health was evaluated by self-report using the Beck Youth Inventories of Emotional and Social Impairment and the psychosomatic problem scale. Peripheral endothelial function was assessed using a peripheral artery tonometry device. The HPA-axis activity measured as cortisol awakening response (CAR) was assessed only at follow-up by collecting two saliva samples, immediately after awakening and 15 min later. Physical activity, smoking and parental education were assessed by questionnaires.

RESULTS

Adolescents reported increased depression and decreased anger over three years, while only females reported increased psychosomatic complaints. Reduced peripheral endothelial function was associated with high level of anger (β = -0.332, p = 0.018) and disruptive behaviour (β = -0.390, p = 0.006) over three years in males, but not in females, after adjusting for covariates. Blunted cortisol awakening response was associated with high level of anxiety (β = -0.235, p = 0.017), depression (β = -0.203, p = 0.038), anger (β = -0.185, p = 0.048), and low level of self-concept (β = 0.289, p = 0.002) after adjusting for covariates.

CONCLUSIONS

High level of negative emotions during adolescence may have adverse effects on peripheral endothelial function and the regulation of the HPA-axis activity, while high level of self-concept might be protective.

Cortisol reactivity and suicidal behavior: Investigating the role of hypothalamic-pituitary-adrenal axis responses to stress in suicide attempters and ideators

Every 40s a person dies by suicide somewhere in the world. The causes of suicidal behavior are not fully understood. Dysregulated hypothalamic-pituitary-adrenal (HPA) axis activity, as measured by cortisol levels, is one potential risk factor. The current study aimed to investigate whether cortisol reactivity to a laboratory stress task differentiated individuals who had previously made a suicide attempt from those who had thought about suicide (suicide ideators) and control participants. One hundred and sixty participants were recruited to a previous attempt, a suicidal ideation or a control group. Participants completed background questionnaires before completing the Maastricht Acute Stress Test (MAST). Cortisol levels were assessed throughout the stress task. Measures of suicide behavior were measured at baseline, 1 month and 6 month follow-up. Participants who had made a previous suicide attempt exhibited significantly lower aggregate cortisol levels during the MAST compared to participants in the control group; suicide ideators were intermediate to both groups. This effect, however, was driven by participants who made an attempt within the past year, and to some degree by those with a family history of attempt. Participants who made a suicide attempt and had a family history of suicide exhibited the lowest levels of cortisol in response to stress. Finally, lower levels of cortisol in response to the MAST were associated with higher levels of suicidal ideation at 1-month follow-up in the suicide attempter group. These results are consistent with other findings indicating that blunted HPA axis activity is associated with some forms of suicidal behavior. The challenge for researchers is to elucidate the precise causal mechanisms linking stress, cortisol and suicide risk.

Stress-induced alterations in estradiol sensitivity increase risk for obesity in women

The prevalence of obesity in the United States continues to rise, increasing individual vulnerability to an array of adverse health outcomes. One factor that has been implicated causally in the increased accumulation of fat and excess food intake is the activity of the limbic-hypothalamic-pituitary-adrenal (LHPA) axis in the face of relentless stressor exposure. However, translational and clinical research continues to understudy the effects sex and gonadal hormones and LHPA axis dysfunction in the etiology of obesity even though women continue to be at greater risk than men for stress-induced disorders, including depression, emotional feeding and obesity. The current review will emphasize the need for sex-specific evaluation of the relationship between stress exposure and LHPA axis activity on individual risk for obesity by summarizing data generated by animal models currently being leveraged to determine the etiology of stress-induced alterations in feeding behavior and metabolism. There exists a clear lack of translational models that have been used to study female-specific risk. One translational model of psychosocial stress exposure that has proven fruitful in elucidating potential mechanisms by which females are at increased risk for stress-induced adverse health outcomes is that of social subordination in socially housed female macaque monkeys. Data from subordinate female monkeys suggest that increased risk for emotional eating and the development of obesity in females may be due to LHPA axis-induced changes in the behavioral and physiological sensitivity of estradiol. The lack in understanding of the mechanisms underlying these alterations necessitate the need to account for the effects of sex and gonadal hormones in the rationale, design, implementation, analysis and interpretation of results in our studies of stress axis function in obesity. Doing so may lead to the identification of novel therapeutic targets with which to combat stress-induced obesity exclusively in females.

Cortisol levels and suicidal behavior: A meta-analysis

Suicide is a major cause of death worldwide, responsible for 1.5% of all mortality. The causes of suicidal behavior are not fully understood. Dysregulated hypothalamic-pituitary-adrenal (HPA) axis activity, as measured by cortisol levels, is one potential risk factor. This meta-analytic review aimed (i) to estimate the strength and variability of the association between naturally fluctuating cortisol levels and suicidal behavior and (ii) to identify moderators of this relationship. A systematic literature search identified 27 studies (N=2226; 779 suicide attempters and 1447 non-attempters) that met the study eligibility criteria from a total of 417 unique records initially examined. Estimates of effect sizes (r) obtained from these studies were analysed using Comprehensive Meta-Analysis. In these analyses, we compared participants identified as having a past history of suicide attempt(s) to those with no such history. Study quality, mean age of sample and percentage of male participants were examined as potential moderators. Overall, there was no significant effect of suicide group on cortisol. However, significant associations between cortisol and suicide attempts were observed as a function of age. In studies where the mean age of the sample was below 40 years the association was positive (i.e., higher cortisol was associated with suicide attempts; r=.234, p<.001), and where the mean age was 40 or above the association was negative (i.e., lower cortisol was associated with suicide attempts; r=-.129, p<.001). These findings confirm that HPA axis activity, as indicated by age-dependent variations in cortisol levels, is associated with suicidal behavior. The challenge for theory and clinical practice is to explain the complete reversal of the association with age and to identify its clinical implications.

High reactivity of the cortisol awakening response predicts positive treatment outcome in heterogeneous depressed patients completing an alternate milieu inpatient program

OBJECTIVE

Delineating clinically meaningful subgroups within heterogeneous depressed populations is a major challenge. As outlined in the Research Domain Criteria Strategy, biomarkers may help to empirically classify such patients. Following this basic strategy, the current pilot study examined whether the cortisol awakening response (CAR) following admission to hospital predicts treatment response in heterogeneous depressed patients completing a 4-week alternate milieu inpatient program.

METHODS

The Alternate Inpatient Milieu program at the Centre for Addiction and Mental Health is composed of both individual-based and group-based programming designed to promote a recovery-oriented, collaborative treatment environment. The current sample consisted of 25 consecutive patients with various forms of complex/chronic depression who completed the full program. Saliva samples were collected at 0, 30 and 60 min after awakening on 2 consecutive days following admission. Linear regressions controlling for baseline depression scores were used to assess whether the CAR AUCg (area under the curve ground) and/or AUCi (area under the curve increase) at admission predicted the change in depression scores from admission to discharge based on the Quick Inventory of Depressive Symptoms scale.

RESULTS

The CAR AUCi, but not the CAR AUCg, at admission significantly predicted treatment response over the 4-week hospital stay. In these naturalistic patients with major depressive disorder, high CAR reactivity as assessed using the AUCi was associated with a better treatment response (t=2.20; df=2,24; P=.039). The CAR was easy to implement and well accepted by patients and staff.

CONCLUSION

This pilot study suggests that CAR reactivity at admission may help to identify a subgroup of depressed patients most likely to respond clinically to a 4-week alternate milieu inpatient program.

The psychophysiological and health corollaries of child problem behaviours in caregivers of children with autism and ADHD

BACKGROUND

The positive relationship between problem behaviours of children with additional complex needs and psychological distress in their caregivers has been widely evidenced. Fewer studies, however, have assessed the relationship between care recipients' problem behaviours and key physiological processes, relevant for the physical health status of their care providers. This study examined the psychological, endocrine and health corollaries of child problem behaviours in caregivers of children with autism and attention deficit hyperactivity disorder.

METHODS

Caregivers (n = 18) completed self-report measures of psychological distress, child problem behaviours and incidences of commonly occurring ailments. To capture important parameters of the basal diurnal cortisol pattern, caregivers collected saliva samples at waking, 30 min post waking, 1200 h and 2200 h on two consecutive weekdays.

RESULTS

Data revealed a positive relationship between caregivers' perceived levels of stress and problems with child conduct behaviours. In addition, caregivers who reported more problems with child emotional and hyperactivity behaviours displayed atypical cortisol patterns characterised by flatter diurnal cortisol slopes and reduced cortisol awakening response magnitude. Subjective reports of commonly occurring ailments were also greater in caregivers experiencing more problems with child emotional behaviours.

CONCLUSIONS

These findings have implications for interventions that aim to improve the psychophysiological well-being of the caregiver by targeting problem behaviours of the care recipient.

Chronic stress-like syndrome as a consequence of medial site subthalamic stimulation in Parkinson's disease

Considering the functional organization of the subthalamic nucleus (STN), we hypothesized that subthalamic deep brain stimulation (STN-DBS) in Parkinson's disease might have a differential impact on the hypothalamic-pituitary-adrenal axis in relation to the position of active stimulating contact within the STN. In addition, we searched for any STN-DBS-related morning plasma cortisol changes in association with postoperative anxiety and weight gain. A plasma cortisol measurement was performed on the day of initiation of bilateral STN-DBS and repeated after 1 and 17 months in twenty patients with advanced Parkinson's disease. The body weight change and anxiety scores following the implantation were assessed as well. The electrode positions in the STN were determined on T1-weighted magnetic resonance images. After initiation of stimulation, cortisol levels significantly decreased and the cortisol changes after 1 and 17 months strongly correlated with the position of active contact in the subthalamic area. Patients with at least one contact located more medially in the STN experienced a significantly greater decrease of cortisol than those with one or both active contacts more laterally. Furthermore, the lower cortisol levels were strongly associated with higher trait anxiety and weight gain. These changes mimicked the effects of chronic stress and suggest the disturbing impact of STN-DBS on limbic and motivational systems.

Illness severity, trait anxiety, cognitive impairment and heart rate variability in bipolar disorder

Numerous studies have documented a significant association between symptom severity and cognitive functioning in bipolar disorder (BD). These findings advanced speculations about a potential link between the physiological stress associated with illness severity and cognitive dysfunction. To explore this hypothesis, the current study employed heart rate variability (HRV) as a physiological measure that is sensitive to the effects of chronic stress, and a scale of trait anxiety for assessing a psychological condition that is correlated with hyper sympathetic arousal. Analyses indicated that BD patients with High Illness Severity reported more symptoms of trait-anxiety (i.e., State Trait Anxiety Inventory), performed more poorly on a computerized neuropsychological battery (i.e., CNS Vital Signs), and exhibited a more constricted HRV profile (i.e., lower SDNN with elevated LF/HF ratio) than patients with Low Illness Severity. Illness severity was determined by a history of psychosis, illness duration, and number of mood episodes. A third group of healthy controls (n=22) performed better on the neuropsychological battery and exhibited a healthier HRV profile than the BD groups. This study provides preliminary evidence that illness severity and cognitive impairment in BD may be associated with state anxiety and neuro-cardiac alterations that are sensitive to physiological stress.

Exploring day-to-day dynamics of daily stressor appraisals, physical symptoms and the cortisol awakening response

Stress is associated with the secretion of cortisol throughout the day, but less is known about the dynamic effects of stress on the cortisol awakening response (CAR). More widely, knowledge of the causal factors and functions of the CAR are also not fully understood. This study explored: (1) the effects of daily stressors on the next day CAR and; (2) the effects of the CAR on same day physical and affective outcomes. Sixty-four participants completed a daily diary, reporting on the occurrence of daily stressors and stress appraisals, physical symptoms, and affect. Cortisol was measured at 0, 15, 30, and 45 min after awakening to provide measures of the CAR on 3 consecutive work days. Stress appraisal was found to negatively predict the CAR, such that where stressors were appraised as more stressful (where perceived demands exceeded resources), the CAR increased less the following morning. Furthermore, the CAR significantly predicted same-day physical symptoms such that a lower CAR was associated with more physical symptoms. This study provides evidence for a pathway through which daily stressors may influence physical wellbeing, and highlights the importance of appraisals for future stress-based cortisol research.

Daily stress magnifies the association between cognitive decline and everyday memory problems: an integration of longitudinal and diary methods

We examined whether long-term fluid cognitive decline was associated with memory problems in everyday life, and whether stress plays a moderating role. We expected that the association between cognitive decline and everyday memory problems would be magnified in the context of self-reported and physiological stress. Data are from the Boston Longitudinal Study, a subsample of the Midlife in the United States study. Participants in the current study (n = 112) completed a battery of tests measuring fluid cognitive functioning at Time 1 (T1) and 2 (T2) over 10 years. At T2, participants completed weekly diaries of self-reported daily stressors and everyday memory problems for 12 consecutive weeks. Also at T2, participants provided 4 saliva samples over the course of 1 day to assess physiological stress using diurnal cortisol profiles [cortisol awakening response (CAR) and diurnal cortisol slope (DCS)]. Self-reported daily stressors and a less healthy DCS were associated with more everyday memory problems, and participants with greater cognitive decline reported more memory problems compared to those with less or no decline. Self-reported daily stressors and CAR moderated the relationship of cognitive decline and memory problems. As expected, more cognitive decline was associated with greater increases in memory problems on weeks when individuals reported more daily stressors and for individuals with a less healthy CAR. The current findings can inform interventions aimed to identify factors, such as daily stress, that contribute to daily functioning in the context of cognitive decline.

Everyday Discrimination Prospectively Predicts Inflammation Across 7-Years in Racially Diverse Midlife Women: Study of Women's Health Across the Nation

Self-reported discrimination has emerged as a predictor of negative psychological and physical health outcomes across racial/ethnic groups. The goals of this study were to determine whether C-reactive protein (CRP), a marker of inflammation and risk factor for future cardiovascular disease (CVD) was independently predicted by everyday discrimination or whether race or body mass index (BMI) modified this association over a 7-year period among 2,490 women from racially diverse backgrounds. At baseline, the 10-item Williams' measure of everyday discrimination was administered. Generalized estimating equations were used to assess these associations. Descriptive results showed that Black and Chinese women reported greater discrimination than White, Japanese, and Hispanic women, while Black and Hispanic women had the highest levels of CRP over the 7-year period. There was no main effect of everyday discrimination (B = .003, SE = .005, p = .58) and this association did not differ as a function of race (p's > .05). The everyday discrimination × BMI interaction term significantly predicted higher CRP levels over time in the full sample of women (p = .03). Specifically, in non-obese women (BMI less than 30), higher perceived everyday discrimination was associated with higher CRP levels over the 7-year period. These findings were independent of demographic, negative affect, biomedical, and behavioral factors. The results demonstrate that greater everyday discrimination is associated with increased inflammation over time in non-obese women. These findings highlight the implications of interpersonal sources of social stress for long-term physical health via their impact on intermediary biological pathways, specifically inflammation. Greater emphasis on such linkages is warranted as we work towards ameliorating health disparities exacerbated by individual-level factors.

Diurnal salivary cortisol in relation to perceived stress at home and at work in healthy men and women

This study investigated the association between diurnal salivary cortisol profile and perceived stress at work and at home. Healthy participants (N=180, 52% women) collected saliva cortisol samples immediately after waking up, 15 min later, 30 min later, and at 9:00, 12:00, 15:00, 18:00 and 21:00. The area under the cortisol awakening curve with respect to ground (AUCgCAR) and increase (AUCiCAR), and diurnal slope between 9:00 and 21:00 were analyzed. Perceived stress at work and at home was measured with the Stress-Energy Questionnaire. Participants reporting stress at home had significantly lower AUCgCAR and a flatter diurnal slope. When performing separate analyses for men and women, this association was only significant among women. Perceived stress at work was not associated with any cortisol measure. This study highlights the importance of stress outside the workplace. The sex differences may indicate an increased vulnerability to non-work stress in women.

Diurnal patterns and associations among salivary cortisol, DHEA and alpha-amylase in older adults

BACKGROUND

Cortisol and dehydroepiandrosterone (DHEA) are considered to be valuable markers of the hypothalamus-pituitary-adrenal (HPA) axis, while salivary alpha-amylase (sAA) reflects the autonomic nervous system. Past studies have found certain diurnal patterns among these biomarkers, with some studies reporting results that differ from others. Also, some past studies have found an association among these three biomarkers while other studies have not. This study investigates these patterns and associations in older adults by taking advantage of modern statistical methods for dealing with non-normality, outliers and curvature. Basic characteristics of the data are reported as well, which are relevant to understanding the nature of any patterns and associations.

METHODS

Boxplots were used to check on the skewness and presence of outliers, including the impact of using simple transformations for dealing with non-normality. Diurnal patterns were investigated using recent advances aimed at comparing medians. When studying associations, the initial step was to check for curvature using a non-parametric regression estimator. Based on the resulting fit, a robust regression estimator was used that is designed to deal with skewed distributions and outliers.

RESULTS

Boxplots indicated highly skewed distributions with outliers. Simple transformations (such as taking logs) did not deal with this issue in an effective manner. Consequently, diurnal patterns were investigated using medians and found to be consistent with some previous studies but not others. A positive association between awakening cortisol levels and DHEA was found when DHEA is relatively low; otherwise no association was found. The nature of the association between cortisol and DHEA was found to change during the course of the day. Upon awakening, cortisol was found to have no association with sAA when DHEA levels are relatively low, but otherwise there is a negative association. DHEA was found to have a positive association with sAA upon awakening. Shortly after awakening and for the remainder of the day, no association was found between DHEA and sAA ignoring cortisol. For DHEA and cortisol (taken as the independent variables) versus sAA (the dependent variable), again an association is found only upon awakening.

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

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

Restoring the salivary cortisol awakening response through nasal continuous positive airway pressure therapy in obstructive sleep apnea

Partial and largely conflicting data are currently available on the interplay between obstructive sleep apnea (OSA) and hypothalamus-pituitary-adrenal axis (HPA) activity in adult obese men. This study was performed to evaluate the daily trajectories of salivary cortisol, specifically with respect to the salivary cortisol awakening response (CAR), a common method used to assess HPA axis activity. The main findings of this study were that adult male obese subjects who were newly diagnosed with severe OSA showed the following: (1) a flattening of the CAR; (2) levels of cortisol at awakening that were lower than those of the controls; and (3) maintenance of the physiological circadian activity of the HPA axis, with the highest hormone concentrations produced in the morning and the lowest in the evening. This study was also designed to investigate the effects of 3 and 6 mos of treatment with continuous airways positive pressure (CPAP). CPAP use resulted in a significant recovery of the sleep patterns disrupted by OSA; moreover, mild neuropsychological signs of depression and anxiety in severe OSA patients were concomitantly progressively improved by CPAP treatment. Furthermore, this study reports that 3 and 6 mos of CPAP therapy restored the presence of CAR and was able to significantly reduce the difference in the morning cortisol levels between the OSA and control groups. In conclusion, we report here that compared with obese nonapneic matched controls, OSA patients present a dysregulation of HPA axis activity, as shown by the flattening of the diurnal pattern of cortisol production in response to repeated challenge due to hypoxia and sleep fragmentation. This dysregulation was especially detectable in the first hour after awakening and restored after 3 and 6 mos of treatment with CPAP.

Salivary cortisol levels and the 2-year course of depressive and anxiety disorders

INTRODUCTION

Depression and anxiety disorders have been associated with hyperactivity of the hypothalamic-pituitary adrenal (HPA) axis. However, lower cortisol levels have also been observed in depressed patients. Whether cortisol level predicts the course of these disorders has not been examined in detail. We examined whether salivary cortisol indicators predict the 2-year course of depression and anxiety disorders.

METHODS

Longitudinal data are obtained from 837 participants of the Netherlands Study of Depression and Anxiety, with a DSM-IV based depressive and/or anxiety disorder at baseline. At baseline, seven saliva samples were obtained, including the 1-h cortisol awakening response, evening cortisol level and a 0.5mg dexamethasone suppression test. At follow-up, DSM-IV based diagnostic interviews and Life Chart Interview integrating diagnostic and symptom trajectories over 2 years were administered to determine an unfavorable course.

RESULTS

41.5% of the respondents had a 2-year unfavorable course trajectory without remission longer than 3 months. Adjusted analyses showed that a lower awakening response was associated with an unfavorable course (RR=0.83, p=0.03). No associations were found between evening cortisol or cortisol suppression after dexamethasone ingestion and an unfavorable course trajectory.

CONCLUSIONS

Among patients with depressive or anxiety disorders, a lower cortisol awakening response - which may be indicative of underlying exhaustion of the HPA axis - predicted an unfavorable course trajectory.

Perceived stress and biological risk: is the link stronger in Russians than in Taiwanese and Americans?

Allostatic load theory implies a relationship between exposure to psychological stress and multi-system physiological dysregulation. We used data from population-based samples of men and women in Russia (Moscow; n = 1800; age, mean 68.6 years), Taiwan (n = 1036; 65.6 years) and the United States (US; n = 1054; 58.0 years) -- which are likely to vary widely with respect to levels of stress exposure and biological markers -- to determine the magnitude of the association between perceived stress and physiological dysregulation. The measure of overall dysregulation was based on 15 markers including standard cardiovascular/metabolic risk factors as well as markers of inflammation and neuroendocrine activity. Subjective psychological stress was measured by the perceived stress scale. Only the Moscow sample demonstrated a positive association with overall dysregulation in both sexes. In the US, we found an association among women but not men. Among the Taiwanese, who report the lowest perceived stress, there was no association in women but an unexpected inverse relationship in men. The effects also varied across system-level subscores: the association with perceived stress was most consistent for standard cardiovascular/metabolic factors. Perceived stress was associated with inflammation and neuroendocrine activity in some samples. Although the evidence that perceived stress is the primary source of physiological dysregulation is generally modest, it was stronger in Russia where the level of perceived stress was particularly high. For Russia only, we had information about heart function based on a 24 h ambulatory electrocardiogram; perceived stress was consistently associated with heart rate dysregulation in Russian men and women.

Cortisol secretion in depressed, and at-risk adults

Distinct patterns of cortisol secretion have been associated with depression in past research, but it remains unclear whether individuals at-risk for depression may also have similar patterns of cortisol secretion. This is the first study to date of both naturalistic diurnal cortisol secretion and cortisol reactivity to a psychosocial laboratory stressor in depressed and at-risk adults. Cortisol secretion patterns were compared for 57 currently depressed, at-risk (based on trait-level positive and negative affect), and control participants over 5 days and in response to a laboratory stressor. After controlling for potentially confounding biobehavioral variables, the depressed group had a larger cortisol awakening response (CAR) and higher average diurnal cortisol compared to control participants. Individuals at-risk for depression also had significantly higher waking cortisol levels than control participants. Results for the psychosocial laboratory stressor did not show the predicted elevations in cortisol for depressed and at-risk participants compared to controls. The at-risk group recovered more quickly when compared to the depressed group both in levels of cortisol and concurrent measures of negative affect. The at-risk and depressed participants were similar on the diurnal cortisol measures, but differed on response to the laboratory social stressor, suggesting divergence in cortisol secretion patterns between currently depressed and temperamentally at-risk individuals. Further investigation of HPA functioning of individuals at-risk for depression may clarify the stress processes involved in risk for depression onset.

Hair cortisol reflects socio-economic factors and hair zinc in preschoolers

This study examined the relationship between children's hair cortisol and socioeconomic status of the family, as measured by parental education and income. Low family socioeconomic status has traditionally been considered a long-term environmental stressor. Measurement of hair cortisol provides an integrated index of cumulative stress exposure across an extended period of time. The present study is the first to examine the relationship between hair cortisol and parental education as well as parental income in a representative sample of preschoolers. Data on hair cortisol, family income, and parental education were collected for a representative sample of 339 children (Mean age=4.6 years; SD=.5 years) from across 23 neighbourhoods of the city of Vancouver, Canada. As maternal education was shown previously to be associated with hair zinc level, hair zinc measurements were included as well in order to explore potential relationships between hair zinc and hair cortisol. The relationship between hair cortisol and parental education was examined using hierarchical regression, with hair zinc, gender, age, and single parenthood included as covariates. Maternal and paternal education both were correlated significantly with hair cortisol (r=-0.18; p=.001). The relationship remained statistically significant even after controlling for all demographic covariates as well as for hair zinc and after taking the neighbourhood-level clustering of the data into account. Parental income, on the other hand, was not related significantly to children's hair cortisol. This study provides evidence that lower maternal and paternal education are associated with higher hair cortisol levels. As hair cortisol provides an integrated index of cortisol exposure over an extended time period, these findings suggest a possibly stable influence of SES on the function of the hypothalamic-pituitary-adrenal (HPA) axis. Cumulative exposure to cortisol during early childhood may be greater in children from low socio-economic backgrounds, possibly through increased exposure to environmental stressors.

Stress-related thinking predicts the cortisol awakening response and somatic symptoms in healthy adults

OBJECTIVE

Perseverative cognition (i.e., worry, stress-related thinking) may prolong stress-related physiological activation. However, its role within the context of the written emotional disclosure paradigm has not been examined. This study explored: (1) the effects of stress-related thinking on the cortisol awakening response and upper respiratory infection symptoms and; (2) the efficacy of two expressive writing interventions on these health outcomes.

METHODS

Participants were randomly assigned to write about their most stressful life experience (using the Guided Disclosure Protocol; n=39) or positive life experiences (n=42) or plans for the day (n=41) for 20 min on 3 consecutive days. Participants reported the extent to which they thought about their assigned writing topic during the study and in the past (event-related thought). Cortisol was measured at 0, 15, 30 and 45 min after awakening on 2 consecutive days at baseline and 4 weeks post-intervention. Upper respiratory infection (URI) symptoms were assessed at baseline, at 4 weeks and at 6 months.

RESULTS

Results showed that the writing interventions had no beneficial effects on any of the outcome measures. However, a significant interaction was found between event-related thought and condition on the cortisol awakening response at 1 month follow-up and URI symptoms at 6 months. Among participants who wrote about stressful/traumatic events, higher stress-related thinking during the study predicted increased cortisol levels and URI symptoms compared to participants who reported low stress-related thinking.

DISCUSSION

These findings are broadly consistent with Brosschot et al.'s (2006) perseverative cognition hypothesis and highlight the importance of ruminative thinking in understanding stress-health processes.

The cortisol awakening response and memory performance in older men and women

The activity and regulation of the hypothalamus-pituitary-adrenal axis has been related to cognitive decline during aging. This study investigated whether the cortisol awakening response (CAR) is related to memory performance among older adults. The sample was composed of 88 participants (44 men and 44 women) from 55 to 77 years old. The memory assessment consisted of two tests measuring declarative memory (a paragraph recall test and a word list learning test) and two tests measuring working memory (a spatial span test and a spatial working memory test). Among those participants who showed the CAR on two consecutive days, we found that a greater CAR was related to poorer declarative memory performance in both men and women, and to better working memory performance only in men. The results of our study suggest that the relationship between CAR and memory performance is negative in men and women when memory performance is largely dependent on hippocampal functioning (i.e. declarative memory), and positive, but only in men, when memory performance is largely dependent on prefrontal cortex functioning (i.e. working memory).