Assessing cortisol from hair samples in a large observational cohort: The Whitehall II study

Physiological and genomic signatures of war and displacement: A comprehensive literature review and future directions

There are now 108.4 million forcibly displaced people worldwide, many of whom endure adversities that result in trauma, toxic stress, and potentially, altered epigenetic development. This paper provides a comprehensive review of current literature on the biological signatures of war and forced migration among refugee populations. To consolidate evidence and identify key concerns and avenues for future research, we reviewed 36 publications and one article under review, published since 2000, most of which focused on refugees relocated in Europe and the Middle East. This body of work - including cross-sectional, observational, and experimental studies - reveals heterogenous findings regarding human biological responses to war-related adversities and their associations with health outcomes. We conclude with four main observations, regarding why genomic and physiological biomarkers are valuable, what study designs advance understanding of causality and health-promoting interventions, how to prepare for ethical challenges, and why theoretical frameworks and research procedures need more detailed consideration in scientific publications.

Is social disadvantage a chronic stressor? Socioeconomic position and HPA axis activity among older adults living in England

INTRODUCTION

Living in socioeconomic disadvantage has been conceptualised as a chronic stressor, although this contradicts evidence from studies using hair cortisol and cortisone as a measure of hypothalamus-pituitary-adrenal (HPA)1 axis activity. These studies used complete case analyses, ignoring the impact of missing data for inference, despite the high proportion of missing biomarker data. The methodological limitations of studies investigating the association between socioeconomic position (SEP)2 defined as education, wealth, and social class and hair cortisol and cortisone are considered in this study by comparing three common methods to deal with missing data: (1) Complete Case Analysis (CCA),3 (2) Inverse Probability Weighting (IPW) 4and (3) weighted Multiple Imputation (MI).5 This study examines if socioeconomic disadvantage is associated with higher levels of HPA axis activity as measured by hair cortisol and cortisone among older adults using three approaches for compensating for missing data.

METHOD

Cortisol and cortisone levels in hair samples from 4573 participants in the 6th wave (2012-2013) of the English Longitudinal Study of Ageing (ELSA)6 were examined, in relation to education, wealth, and social class. We compared linear regression models with CCA, weighted and multiple imputed weighted linear regression models.

RESULTS

Social groups with certain characteristics (i.e., ethnic minorities, in routine and manual occupations, physically inactive, with poorer health, and smokers) were less likely to have hair cortisol and hair cortisone data compared to the most advantaged groups. We found a consistent pattern of higher levels of hair cortisol and cortisone among the most socioeconomically disadvantaged groups compared to the most advantaged groups. Complete case approaches to missing data underestimated the levels of hair cortisol in education and social class and the levels of hair cortisone in education, wealth, and social class in the most disadvantaged groups.

CONCLUSION

This study demonstrates that social disadvantage as measured by disadvantaged SEP is associated with increased HPA axis activity. The conceptualisation of social disadvantage as a chronic stressor may be valid and previous studies reporting no associations between SEP and hair cortisol may be biased due to their lack of consideration of missing data cases which showed the underrepresentation of disadvantaged social groups in the analyses. Future analyses using biosocial data may need to consider and adjust for missing data.

Weight stigma as a stressor: A preliminary multi-wave, longitudinal study testing the biobehavioral pathways of the cyclic obesity/weight-based stigma (COBWEBS) model

Higher weight individuals often face significant weight stigma. According to the Cyclic Obesity/Weight-Based Stigma (COBWEBS) model, weight stigma operates as a stressor that increases the stress hormone cortisol and promotes comfort eating, thus resulting in weight gain. Such weight gain is harmful as it exposes individuals to further stigmatization. Thus far, no study has yet tested the mechanistic pathways of the COBWEBS model and prospective longitudinal studies are severely lacking. To fill this gap, the current study tested the biobehavioral pathways of the COBWEBS model using a 4-wave yearlong longitudinal study comprising 348 higher weight individuals. Using a structural equation modeling framework, we tested three cross lagged panel models for the putative mediator, comfort eating. The models examined either synchronous and/or lagged effects across weight stigma, perceived stress, comfort eating, weight, and future weight stigma. The best fitting model revealed significant associations between baseline weight stigma, perceived stress, and comfort eating within the same month. However, comfort eating did not significantly predict weight four months later. Weight status and baseline weight stigma both predicted future weight stigma as expected. Additionally, a separate path model with hair cortisol found that weight stigma predicted perceived stress four months later, but stress did not predict aggregate cortisol levels from months 10 and 11. Hair cortisol also did not predict later weight. This preliminary work lays the foundation for identifying modifiable targets of weight stigma, thereby offering potential avenues to reduce weight stigma's harm on higher weight individuals.

Hair cortisol determinants in 11-year-old children: Environmental, social and individual factors

INTRODUCTION

Children's exposure to chronic stress is associated with several health problems. Measuring hair cortisol concentration is particularly useful for studying chronic stress but much is unknown about hair cortisol determinants in children and adolescents, and previous research has often not considered the simultaneous exposure of multiple variables. This research is focused on investigating the relationship between environmental, social and individual factors with hair cortisol concentration in children.

METHODS

The data used in this study are from the INMA prospective epidemiological cohort study. The assessment of chronic stress was made on the basis of hair samples taken at the age of 11 years in the INMA-Gipuzkoa cohort (n = 346). A metamodel summarizing the hypothesized relationships among environmental, social and individual factors and hair cortisol concentration was constructed based on previous literature. Structural Equation Modelling was performed to examine the relationships among the variables.

RESULTS

In the general model higher behavioural problems were associated with higher cortisol levels and an inverse relationship between environmental noise and cortisol levels was observed, explaining 5 % of the variance in HCC. Once stratified by sex these associations were only hold in boys, while no significant effect of any of the study variables was related with cortisol levels in girls. Importantly, maternal stress was positively related to behavioural difficulties in children. Finally, higher traffic-related air pollution and lower exposure to neighborhood greenness were related to higher environmental noise.

DISCUSSION

This study highlights that simultaneous exposure to different environmental, social and individual characteristics may determine the concentration of hair cortisol. More research is needed and future studies should include this complex view to better understanding of hair cortisol determinants in children.

Recruitment and retention of adolescents for an ecological momentary assessment measurement burst mental health study: The MHIM engagement strategy

INTRODUCTION

Recruitment and long-term retention of adolescent participants in longitudinal research are challenging and may be especially so in studies involving remote measurement and biosampling components. The ability to effectively recruit and retain participants can be supported by the use of specific evidence-based engagement strategies that are built in from the earliest stages.

METHODS

Informed by a review of the evidence on effective engagement strategies and consultations with adolescents (via two Young Person Advisory Groups [YPAGs]; ages 11-13 and 14-17), the current protocol describes the planned participant engagement strategy for the Mental Health in the Moment Study: a multimodal measurement burst study of adolescent mental health across ages 11-19.

RESULTS

The protocol incorporates engagement strategies in four key domains: consultations/co-design with the target population, incentives, relationship-building and burden/barrier reduction. In addition to describing general engagement strategies in longitudinal studies, we also discuss specific concerns regarding engagement in data collection methods such as biosampling and ecological momentary assessment where a paucity of evidence exists.

CONCLUSION

Engagement strategies for adolescent mental health studies should be based on existing evidence and consultations with adolescents. We present our approach in developing the planned engagement strategies and also discuss limitations and future directions in engaging adolescents in longitudinal research.

PATIENT OR PUBLIC CONTRIBUTION

The study design for this project places a strong emphasis on the active engagement of adolescents throughout its development. Specifically, the feedback and suggestions provided by the YPAGs have been instrumental in refining our strategies for maximising the recruitment and retention of participants.

Elevated parent and child hair cortisol moderated the efficacy of a mindful eating intervention

To explore whether elevated baseline hair cortisol moderated effects of a mindful eating intervention on anthropometrics, blood pressure (BP), household food insecurity, eating behaviour, and various psychosocial outcomes. The 14-week intervention included a parent Facebook-based programme, 3 parent meetings, preschooler letters connecting school learning to home practices, and a preschool-based mindful eating programme. Among 107 parent-preschooler dyads, mean age was 47.32 months for preschoolers and 30.12 years for parents. Among preschoolers, 54.2% were female, 8.4% were Hispanic, and 19.6% were Black. Among parents, 95.3% were female, 6.5% were Hispanic, 15.0% were Black, 39.4% were single, and 43.4% were unemployed. Preschoolers' elevated hair cortisol was related to a smaller reduction in preschoolers' % body fat (r =.31) and smaller increases in parents' perceived responsibility for child feeding (r = -.37). Parents' elevated hair cortisol was associated with smaller decreases in preschoolers' emotional eating (r = .39) and household food insecurity (r = .44). Relationships between baseline hair cortisol and post-intervention outcomes (BP, emotional eating, fruit/vegetable intake, food insecurity, and coping) varied by baseline values of outcome variables. Given that stress may attenuate intervention effects, a stress management component may be necessary to foster positive behavioural changes. Moreover, interventions should be tailored according to participants' characteristics to achieve optimal effects.

Cross-sectional associations of self-perceived stress and hair cortisol with metabolic outcomes and microvascular complications in type 2 diabetes

Introduction

Increasing evidence supports chronic psychological stress as a risk factor for the development of type 2 diabetes. Much less is known, however, about the role of chronic stress in established diabetes.

Methods

The aim of the current study was to comprehensively assess chronic stress in a sample of 73 patients with type 2 diabetes and 48 non-diabetic control participants, and to investigate associations with indicators of glycemic control (HbA1c), insulin resistance (HOMA-IR), β-cell functioning (C-peptide), illness duration, and the presence of microvascular complications. Chronic stress was measured using questionnaires [the Perceived Stress Scale (PSS), the Screening Scale of the Trier Inventory of Chronic Stress (SSCS), the Perceived Health Questionnaire (PHQ) as well as the Questionnaire on Stress in Patients with Diabetes-Revised (QSD-R)]; hair cortisol was used as a biological indicator.

Results

We found that patients with type 2 diabetes had higher levels of hair cortisol in comparison to the control group (F(1,112) = 5.3; p = 0.023). Within the diabetic group, higher hair cortisol was associated with a longer duration of the illness (r = 0.25, p = 0.04). General perceived stress did not show significant associations with metabolic outcomes in type 2 diabetes patients. In contrast, higher diabetes-related distress, as measured with the QSD-R, was associated with lower glycemic control (r = 0.28, p = 0.02), higher insulin resistance (r = 0.26, p = 0.03) and a longer duration of the illness (r = 0.30, p = 0.01).

Discussion

Our results corroborate the importance of chronic psychological stress in type 2 diabetes. It appears, however, that once type 2 diabetes has developed, diabetes-specific distress gains in importance over general subjective stress. On a biological level, increased cortisol production could be linked to the course of the illness.

Hair hormone data from Syrian refugee children: Perspectives from a two-year longitudinal study

For numerous issues of convenience and acceptability, hair hormone data have been increasingly incorporated in the field of war trauma and forced displacement, allowing retrospective examination of several biological metrics thought to covary with refugees' mental health. As a relatively new research method, however, there remain several complexities and uncertainties surrounding the use of hair hormones, from initial hair sampling to final statistical analysis, many of which are underappreciated in the extant literature, and restrict the potential utility of hair hormones. To promote awareness, we provide a narrative overview of our experiences collecting and analyzing hair hormone data in a large cohort of Syrian refugee children (n = 1594), across two sampling waves spaced 12 months apart. We highlight both the challenges faced, and the promising results obtained thus far, and draw comparisons to other prominent studies in this field. Recommendations are provided to future researchers, with emphasis on longitudinal study designs, thorough collection and reporting of hair-related variables, and careful adherence to current laboratory guidelines and practices.

Hair cortisol stability after 5-year storage: Insights from a sample of 17-year-old adolescents

Background

Hair has become an increasingly valuable medium to investigate the association between chronic stress, stable differences in systemic cortisol secretion and later health. Assessing cortisol in hair has many advantages, notably its non-invasive and retrospective nature, the need for a single biospecimen and convenient storage until analysis. However, few studies offered empirical evidence documenting the long-term temporal stability of hair cortisol concentration (HCC) prior to analysis, especially in humans. Yet, knowing how long hair samples can be stored without compromising the accuracy of cortisol measurement is of crucial importance when planning data collection and analysis. This study examined the stability of HCC in hair samples assayed twice, five years apart.

Methods

We randomly selected from a larger distribution of HCC measured in 17-year-old participants 39 hair samples to be reanalyzed five years later, under the same general conditions. Samples were assayed in duplicate using a luminescence immunoassay and compared with the original HCC using the Lin's concordance correlation coefficient (CCC), Bland-Altman plot analysis and Wilcoxon rank test.

Results

Findings indicated a good concordance and temporal stability between the two samples assayed five years apart (CCC [95% confidence interval] = 0.84 [0.72-0.91]), although a small decrease in HCC was noted 5 years later (8.4% reduction, p = 0.001).

Conclusion

Our study confirms that hair samples, when stored at room temperature and away from sunlight, can be assayed for at least five years without risking a loss of precision in HCC measurement.

Prospective associations of technostress at work, burnout symptoms, hair cortisol, and chronic low-grade inflammation

BACKGROUND

Working conditions in the age of digitalization harbor risks for chronic stress and burnout. However, real-world investigations into biological effects of technostress, that is stress in the context of digital technology use, are sparse. This study prospectively assessed associations between technostress, general work stress, burnout symptoms, hair cortisol, and chronic low-grade inflammation.

METHODS

Hospital employees (N = 238, 182 females, Mage = 28.5 years) participated in a prospective cohort study with two follow-ups six months apart (T2, T3). Participants answered standardized questionnaires on general job strain (job demand-control ratio), technostressors (work interruptions, multitasking, information overload), burnout symptoms (exhaustion, mental distance), and relevant confounders. Moreover, they provided capillary blood samples for C-reactive protein (CRP) and hair strands for hair cortisol concentration (HCC) analysis. Structural equation modelling was performed.

RESULTS

The factorial structure of survey measures was confirmed. Burnout symptoms (MT2 = 2.17, MT3 = 2.33) and HCC (MT2 = 4.79, MT3 = 9.56; pg/mg) increased over time, CRP did not (MT2 = 1.15, MT3 = 1.21; mg/L). Adjusted path models showed that technostress was negatively associated with HCC (β = -0.16, p =.003), but not with burnout and CRP. General work stress in contrast, was not significantly associated with burnout, HCC or CRP. Furthermore, there were reciprocal effects of CRP on HCC (β = 0.28, p =.001) and of HCC on CRP (β = -0.10, p ≤.001). Associations were robust in additional analyses including further confounders.

CONCLUSION

This is the first study on prospective effects of technostress on employees' endocrine and inflammatory systems. Results suggest differential effects of technostress on the hypothalamic-pituitary-adrenocortical axis activity. Given its key role for long-term health, the findings have important implications for occupational health and safety in digitalized work environments.

Determination of cortisone and cortisol in human scalp hair using an improved LC-MS/MS-based method

OBJECTIVES

Human scalp hair is an easily available but complex matrix for determination of cortisone and cortisol, and has been shown to reflect long-term glucocorticoid exposure. Hair glucocorticoid analysis has been used to detect hypo- and hypercortisolism. In this study, we describe the development and validation of a LC-MS/MS method for quantification of cortisone and cortisol in human scalp hair, and provide a novel approach for analysis and interpretation of the results.

METHODS

Improved sample preparation using pulverization and solid phase extraction allowed for low sample volumes (10 mg). Baseline chromatographic separation without matrix interference was achieved by reversed phase chromatography and MRM measurement in negative ion mode. Run-to-run time was 8 min. Mixed model analyses were performed to create individual patterns of cortisone and cortisol concentrations.

RESULTS

Matrix matched calibration curves showed excellent linearity up to 100 pg (analyte)/mg (hair) for both cortisone and cortisol (R2>0.995). LLOQ was 1.5 and 1.0 pg/mg for cortisone and cortisol, respectively. Matrix effect was negligible for hair color (recoveries 95-105 %). Cortisone and cortisol concentrations decreased from proximal to distal hair segments, following a predictable, but subject-specific pattern, with less individual variation for cortisone than for cortisol.

CONCLUSIONS

This improved LC-MS/MS method is able to accurately quantify cortisone and cortisol in human hair with minimum matrix interference. This new way of data analysis and interpretation including individual patterns of cortisone and cortisol will be of help with detection of pathological concentrations in both the high - and the low ranges of glucocorticoids.

The association between stress and multiple long-term conditions: A cohort study

BACKGROUND

Stress is an important predictor of long-term conditions. We examine whether hair cortisol (a biomarker of stress) is associated with incidence and accumulation of multiple long-term conditions (MLTC).

METHODS

We included data from 4295 individuals aged ≥50 years within the English Longitudinal Study of Ageing dataset with data on hair cortisol, sociodemographic and health behaviour variables. Cox proportional hazards models were used to quantify the association between hair cortisol at baseline and accumulation of MLTC between 2012/2013 and 2018/2019, both for individuals with and without MLTC at baseline.

RESULTS

Our cohort included 1458 (34.0%) individuals who accumulated MLTC between 2012/2013 and 2018/2019. The proportion of individuals with zero, 1, and ≥ 2 conditions at baseline who accumulated MLTC were 12.0% (n = 127), 40.4% (n = 520), and 41.7% (n = 811), respectively. Higher cortisol levels were associated with higher risk of accumulation of MLTC in both unadjusted [HR:1.15(1.05-1.25)] and models adjusted for sociodemographic and health behaviours [HR:1.12(1.02-1.22)]. For individuals without MLTC at baseline, higher cortisol levels were significantly associated with higher risk of developing MLTC in unadjusted [HR: 1.20(1.05-1.36)] and adjusted models [HR: 1.16(1.02-1.32)].

CONCLUSION

The study provides the first evidence of the role of stress in the development and accumulation of MLTC. This modifiable risk factor could be targeted to reduce the risk of MLTC. However, further work is needed to better understand the mechanisms and pathways that link stress and accumulation of MLTC.

Long-term glucocorticoids in relation to the metabolic syndrome and cardiovascular disease: A systematic review and meta-analysis

The striking link of Cushing's syndrome with the metabolic syndrome (MetS) and cardiovascular disease (CVD) suggests that long-term exposure to extremely high cortisol levels catalyzes cardiometabolic deterioration. However, it remained unclear whether the findings from the extreme glucocorticoid overabundance observed in Cushing's syndrome could be translated into more subtle variations in long-term glucocorticoid levels among the general population, for example, due to chronic stress. Here, we performed a systematic review (PROSPERO: CRD42023425541) of evidence regarding the role of subtle variations in long-term biological stress, measured as levels of scalp hair cortisol (HairF) and cortisone (HairE), in the context of MetS and CVD in adults. We also performed a meta-analysis on the cross-sectional difference in HairF levels between individuals with versus without CVD. Seven studies were included regarding MetS, sixteen regarding CVD, and one regarding both. Most articles indicated a strong, consistent cross-sectional association of higher HairF and HairE levels with CVD, which was confirmed by our meta-analysis for HairF (eight studies, SMD = 0.48, 95% confidence intervals [CIs]: 0.16-0.79, p = 0.0095). Moreover, these relationships appear largely independent of standard risk factors. Age seems relevant as the effect seems stronger in younger individuals. Results regarding the associations of HairF and HairE with MetS were inconsistent. Altogether, long-term biological stress, measured as HairF and HairE, is associated with the presence of CVD, and less consistently with MetS. Prospective studies need to evaluate the directionality of this relationship and determine whether HairF and HairE can be used in addition to standard risk factors in predicting future cardiometabolic deterioration.

Psychological resilience and cortisol levels in adults: A systematic review

Resilience or the capacity to "bend but not break" refers to the ability to maintain or regain psychobiological equilibrium during or after exposure to stressful life events. Specifically, resilience has been proposed as a potential resource for staving off pathological states that often emerge after exposure to repeated stress and that are related to alterations in circulating cortisol. The aim of this systematic review of the literature was to gather evidence related to the relationship between psychological resilience and cortisol levels in adult humans. An extensive systematic search was carried out following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method in the PubMed and Web of Science databases. In total, 1256 articles were identified and, of these, 35 peer-reviewed articles were included in the systematic review. We categorized findings according to (1) the short and long-term secretion period covered by the cortisol matrices selected by studies and also according to (2) the differentiated diurnal, phasic (acute), and tonic (basal) components of the HPA output to which they refer and their relationships with resilience. Reported relationships between psychological resilience and distinct cortisol output parameters varied widely across studies, finding positive, negative, and null associations between the two variables. Notably, several of the studies that found no relationship between resilience and cortisol used a single morning saliva or plasma sample as their assessment of HPA axis activity. Despite limitations such as the great variability of the instruments and methods used by the studies to measure both resilience and cortisol, together with their high heterogeneity and small sample sizes, the evidence found in this systematic review points to the potential of resilience as a modifiable key factor to modulate the physiological response to stress. Therefore, further exploration of the interaction between the two variables is necessary for the eventual development of future interventions aimed at promoting resilience as an essential component of health prevention.

Maternal postpartum depressive symptoms: The predictive role of objective and subjective birth experience and hair glucocorticoids

BACKGROUND

Having a negative childbirth experience is a known risk-factor for developing postpartum depression (PPD). Alterations of the hypothalamus-pituitary-adrenal (HPA)-axis have been discussed as a potential underlying mechanism. However, research on the association between negative birth experiences and long-term integrated glucocorticoids (GCs) is lacking. This study aimed to examine whether objective and subjective birth experience predicted long-term GCs and PPD symptoms.

METHODS

Measures of objective and subjective birth experience, PPD symptoms, and hair strands for the assessment of hair cortisol concentrations (HairF), hair cortisone concentrations (HairE), and HairF/HairE ratio, were provided eight weeks after childbirth by 235 mothers participating in the study DREAMHAIR.

RESULTS

A negative objective birth experience predicted a higher HairF/HairE ratio but was not associated with HairF or HairE. The subjective birth experience did not explain additional variance in hair GCs but was a significant predictor for PPD symptoms. A higher HairF/HairE ratio predicted PPD symptoms when controlling for prepartum depressive symptoms and number of lifetime traumatic events.

LIMITATIONS

Analyses were based on a relatively homogeneous sample and women reported in general positive birth experiences and low levels of depressive symptoms. Therefore, results should be applied to the broader population with caution.

CONCLUSIONS

Our results suggest that negative objective birth experience is associated with an altered HairF/HairE ratio, which in turn, seems to be a promising biomarker to identify women at risk for developing PPD. A negative subjective birth experience may be less critical for alterations of the HPA-axis but remains an essential risk factor for PPD.

Effect of cosmetic hair treatment and natural hair colour on hair testosterone concentrations

PURPOSE

Testosterone analysis in hair allows for retrospective evaluation of endogenous testosterone concentrations, but studies devoted to investigating confounders in hair testosterone analysis have hitherto been scarce. The current study examined the stability of testosterone concentrations between two hair samples collected three months apart and investigated two potential confounding factors: natural hair colour and cosmetic hair treatments.

METHODS

Testosterone was analysed with an in-house radioimmunoassay with a limit of detection adequate for the purpose.

RESULTS

The testosterone concentrations from the two samplings, at baseline and three months later, had an intra-individual correlation of moderate strength (rho = 0.378, p<0.001, n = 146). Hair treatment, such as colouring or bleaching, seemed to increase testosterone concentrations (p = 0.051, n = 191, and in a paired analysis in a subset of the cohort p = 0.005, n = 24), while no effect of natural colour in untreated hair (p = 0.133) could be detected.

CONCLUSION

The current results suggest that cosmetic hair treatments need to be considered in hair testosterone analyses and demonstrate the utility of a radioimmunoassay to reliably measure testosterone concentrations in small hair samples in women.

Are hair cortisol levels dependent on hair growth rate? A pilot study in rhesus macaques

Research incorporating the analysis of glucocorticoids, specifically cortisol, in hair samples has exploded over the past 10-15 years, yet factors contributing to the accumulation of cortisol in hair are not yet fully characterized. In particular, it is not clear whether cortisol accumulation in hair is dependent on hair growth rate, a possibility raised by prior rodent studies reporting glucocorticoid-mediated inhibition of hair growth. Using rhesus macaque monkeys (Macaca mulatta), an extensively studied nonhuman primate species, the present pilot study evaluated the hypothesis that hair cortisol accumulation is inversely related to hair growth rate (i.e., slower hair growth leading to elevated cortisol levels). Hair samples were collected from 19 adult female macaques and 17 infants (9 males) 3 months apart using a shave-reshave procedure from the same site below the posterior vertex of the scalp. The second hair samples were measured to the nearest millimeter (mm) for growth rate over the previous 3 months and assayed for hair cortisol concentrations (HCCs) using enzyme immunoassay. Because of the possibility of age-related differences in hair growth rate, correlational analyses were performed separately for adults and infants to determine whether HCC values were associated with growth rate in each age group. These analyses revealed that neither group displayed a significant correlation of HCCs with hair growth. The results additionally showed that overall, adults had a faster hair growth rate than infants and, as expected from previous studies, had lower HCCs than infants. Our results suggest that higher HCCs within the non-stress range do not result from cortisol-mediated inhibition of hair growth. Moreover, similarities between humans and macaque monkeys in both HPA axis regulation and hair growth rates argue that these findings are relevant for human hair cortisol studies. Extrapolation to other species in which the features of hair growth and the relevant regulatory mechanisms are less well understood should be done with caution.

Collaborating to Improve Neonatal Care: ParentAl Participation on the NEonatal Ward-Study Protocol of the neoPARTNER Study

Parents are often appointed a passive role in the care for their hospitalised child. In the family-integrated care (FICare) model, parental involvement in neonatal care is emulated. Parental participation in medical rounds, or family-centred rounds (FCR), forms a key element. A paucity remains of randomised trials assessing the outcomes of FCR (embedded in FICare) in families and neonates, and outcomes on an organisational level are relatively unexplored. Likewise, biological mechanisms through which a potential effect may be exerted are lacking robust evidence. Ten level two Dutch neonatal wards are involved in this stepped-wedge cluster-randomised trial FCR (embedded in FICare) by one common implementation strategy. Parents of infants hospitalised for at least 7 days are eligible for inclusion. The primary outcome is parental stress (PSS:NICU) at discharge. Secondary outcomes include parental, neonatal, healthcare professional and organisational outcomes. Biomarkers of stress will be analysed in parent-infant dyads. With a practical approach and broad outcome set, this study aims to obtain evidence on the possible (mechanistic) effect of FCR (as part of FICare) on parents, infants, healthcare professionals and organisations. The practical approach provides (experiences of) FICare material adjusted to the Dutch setting, available for other hospitals after the study.

Is Smart Working Beneficial for Workers' Wellbeing? A Longitudinal Investigation of Smart Working, Workload, and Hair Cortisol/Dehydroepiandrosterone Sulfate during the COVID-19 Pandemic

Building on the job demands-resources (JD-R) and allostatic load (AL) models, in the present study we examined the role of smart working (SW) in the longitudinal association between workload/job autonomy (JA) and a possible biomarker of work-related stress (WRS) in the hair-namely, the cortisol-dehydroepiandrosterone sulfate (DHEA(S)) ratio-during the COVID-19 pandemic. Overall, 124 workers completed a self-report questionnaire (i.e., psychological data) at Time 1 (T1) and provided a strand of hair (i.e., biological data) three months later (Time 2, T2). Results from moderated multiple regression analysis showed that SW at T1 was negatively associated with the hair cortisol/DHEA(S) ratio at T2. Additionally, the interaction between workload and SW was significant, with workload at T1 being positively associated with the hair cortisol/DHEA(S) ratio at T2 among smart workers. Overall, this study indicates that SW is a double-edged sword, with both positive and negative consequences on employee wellbeing. Furthermore, our findings suggest that the hair cortisol/DHEA(S) ratio is a promising biomarker of WRS. Practical implications that organizations and practitioners can adopt to prevent WRS and promote organizational wellbeing are discussed.

Hair cortisol, cortisone and DHEA concentrations and the composition of microbiota in toddlers

Animal research suggests that the gut microbiota and the HPA axis communicate in a bidirectional manner. However, human data, especially on early childhood, remain limited. In this exploratory design, we investigated the connections between long-term HPA axis functioning, measured as cortisol, cortisone or dehydroepiandrosterone concentrations and their ratios from hair segments of three centimeters, and gut microbiota profiles, (measured as diversity and bacterial composition by 16 S rRNA sequencing) in healthy 2.5-year-old toddlers (n = 135) recruited from the FinnBrain Birth Cohort Study. The alpha diversity of the microbiota was studied by linear regression. Beta diversity analyses with weighted UniFrac or Bray-Curtis distances were performed using PERMANOVA. The bacterial core genus level analyses were conducted using DESeq2 and ALDEx2. These analyses suggested that hair sample concentrations of separate hormones, cortisol/cortisone and cortisol/dehydroepiandrosterone ratios were associated with various gut bacterial genera such as the Veillonella, the [Ruminococcus] torques group and [Eubacterium] hallii group, although multiple testing correction attenuated the p-values. Alpha or beta diversity was not linked with either steroid concentrations or ratios. These findings in toddlers suggest that long-term HPA axis activity may be related to genera abundancies but not to ecosystem-level measures in gut microbiota. The influence of these observed interrelations on later child health and development warrants further research.

Determinants of hair cortisol in preschool children and their mothers: A Brazilian birth cohort study

OBJECTIVE

Few large-scale studies have provided population-based estimates of hair cortisol levels and its determinants. Hair cortisol and potential determinants were measured in children and their mothers in a population-based sample in a Brazilian city with large variations in socioeconomic conditions.

METHODS

We used data from the 4-year follow-up of the 2015 Pelotas (Brazil) Birth Cohort Study. Hair samples were collected by trained fieldworkers to analyze average levels of cortisol over a 3-month period. Four groups of variables were tested as potential determinants: hair characteristics (natural color, treatment, type, and frequency of wash), use of corticosteroids and oral contraceptives, sociodemographic factors (sex, age, skin color, socioeconomic level, maternal relationship, pregnancy, daycare enrollment), maternal perceived stress, and substance exposure (smoking and illicit drug use). Linear regression with log transformation was used to test associations.

RESULTS

3235 children and 3102 mothers were analyzed (80.7% and 77.4% of those interviewed when children were 4 years of age, respectively), for whom sufficient hair was collected for cortisol analysis. The median of hair cortisol concentration was 7.8 pg/mg (IQR = 5.6 - 11.0) for children, and 5.6 pg/mg (IQR = 4.2 - 7.8) for mothers. In adjusted models, sex and socioeconomic level were associated with child cortisol levels. For mothers, hair cortisol levels were associated with socioeconomic level, skin color, age, hair treatment and hair natural color.

CONCLUSION

This study provides estimates of hair cortisol levels in a diverse population in a upper-middle income country. Although just a few predictors were associated with maternal/child cortisol levels, socioeconomic level was the key variable that should be incorporated in studies using hair cortisol to measure biological manifestations of stress, but other variables, such as some hair and sociodemographic characteristics are important to consider when using hair cortisol.

A machine learning-integrated stepwise method to discover novel anti-obesity phytochemicals that antagonize the glucocorticoid receptor

As a type of stress hormone, glucocorticoids (GCs) affect numerous physiological pathways by binding to the glucocorticoid receptor (GR) and regulating the transcription of various genes. However, when GCs are dysregulated, the resulting hypercortisolism may contribute to various metabolic disorders, including obesity. Thus, attempts have been made to discover potent GR antagonists that can reverse excess-GC-related metabolic diseases. Phytochemicals are a collection of valuable bioactive compounds that are known for their wide variety of chemotypes. Recently, various computational methods have been developed to obtain active phytochemicals that can modulate desired target proteins. In this study, we developed a workflow comprising two consecutive quantitative structure-activity relationship-based machine learning models to discover novel GR-antagonizing phytochemicals. These two models collectively identified 65 phytochemicals that bind to and antagonize GR. Of these, nine commercially available phytochemicals were validated for GR-antagonist and anti-obesity activities. In particular, we confirmed that demethylzeylasteral, a phytochemical of the Tripterygium wilfordii Radix, exhibits potent anti-obesity activity in vitro through GR antagonism.

The Role of Major Biomarkers of Stress in Atrial Fibrillation: A Literature Review

Numerous studies have reported that physical or emotional stress can provoke atrial fibrillation (AF) or vice versa, which suggests a potential link between exposure to external stressors and AF. This review article sought to describe in detail the relationship between major stress biomarkers and the pathogenesis of AF and presents up-to-date knowledge on the role of physiological and psychological stress in AF patients. For this purpose, this review article contends that plasma cortisol is linked to a greater risk of AF. A previous study has investigated the association between increased copeptin levels and paroxysmal AF (PAF) in rheumatic mitral stenosis and reported that copeptin concentration was not independently associated with AF duration. Reduced levels of chromogranin were measured in patients with AF. Furthermore, the dynamic activity of antioxidant enzymes, including catalase as well as superoxide dismutase, was examined in PAF patients during a period of <48 h. Malondialdehyde activity, serum high-sensitivity C-reactive protein, and high mobility group box 1 protein concentrations were significantly greater in patients with persistent AF or PAF compared to controls. Pooled data from 13 studies confirmed a significant reduction in the risk of AF related to the administration of vasopressin. Other studies have revealed the mechanism of action of heat shock proteins (HSPs) in preventing AF and also discussed the therapeutic potential of HSP-inducing compounds in clinical AF. More research is required to detect other biomarkers of stress, which have not been reported in the pathogenesis of AF. Further studies are required to identify their mechanism of action and drugs to manage these biomarkers of stress in AF patients, which might help to reduce the prevalence of AF globally.

Diurnal cortisol features with cardiovascular disease in hypertensive patients: a cohort study

OBJECTIVE

The hypothalamic-pituitary-adrenal (HPA) axis may be associated with cardiovascular disease (CVD) and the effects of diurnal cortisol features on future CVD remain unclear among patients with hypertension. This study aimed to evaluate the association between diurnal cortisol features and CVD in patients with hypertension.

DESIGN AND METHODS

Participants with cortisol rhythm test at baseline in Urumqi Research on Sleep Apnea and Hypertension (UROSAH) in 2011-2013 were enrolled and followed up till 2021. Incident events included coronary heart disease, stroke, and heart failure. Cox proportional hazards model was used to evaluate the relationship between diurnal cortisol features and incident CVD. Sex-specific and sensitivity analyses were also performed.

RESULTS

In total, 2305 hypertensive participants comprised the current analytical sample. During a median follow-up of 7.2 years and 16374.9 person-years, there were 242 incident CVD cases. Multivariable Cox regression showed that steep diurnal cortisol slope (DCS) was significantly associated with decreased CVD risk (per s.d., hazard ratio (HR) = 0.86, 95% CI: 0.77-0.96, P = 0.011). Midnight cortisol was positively associated with an increased CVD risk (per s.d., HR = 1.24, 95% CI: 1.08-1.42, P = 0.002). Comparable results were observed in the sensitivity analyses. Neither midnight cortisol nor DCS was associated with incident CVD in the female subgroup.

CONCLUSIONS

Flatter DCS and higher midnight cortisol levels are associated with an increased risk of CVD in patients with hypertension, especially in men. The detection of diurnal cortisol rhythm may help identify patients with hypertension at high risk of CVD.

Can dogs serve as stress mediators to decrease salivary cortisol levels in a population of liberal arts college undergraduate students?

The steroid hormone cortisol can be used to measure physiological stress in humans. The hypothalamic-pituitary-adrenal (HPA) axis synthesizes cortisol, and a negative feedback cycle regulates cortisol depending on an individual's stress level and/or circadian rhythm. Chronic stress of college undergraduate students is associated with various adverse health effects, including anxiety and depression. Reports suggest that stress levels have risen dramatically in recent years, particularly among university students dealing with intense academic loads in addition to COVID-19 pandemic-related uncertainty. The increasing rate of mental illness on college campuses necessitates the study of mediators potentially capable of lowering stress, and thus cortisol levels. Research on mediation techniques and coping mechanisms have gained traction to address the concerning levels of stress, including the employment of human-animal interaction sessions on college campuses. In this study, human-canine interaction as a stress mediation strategy for undergraduate students was investigated. We measured salivary cortisol levels in 73 college undergraduate students during a 60-min interaction period with a dog to determine whether human-canine interactions are effective in lowering cortisol levels and potentially reducing chronic stress typical of undergraduate students. Our results indicate that a human-canine interaction for 60 min is an effective method for significantly reducing salivary cortisol and stress levels among undergraduate college students. These findings support the expansion of animal visitation programs on college campuses to help students manage stress.

Hair cortisol, perceived stress, and resilience as predictors of coronary arterial disease

The widespread prevalence of cardiovascular disease underscores the continuing need for identifying modifiable risk factors and novel targets for therapeutic intervention. Hair cortisol concentration (HCC) is a promising biomarker for evaluating the contribution of chronic stress to the pathogenesis and prognosis of coronary arterial disease (CAD). In this cross-sectional study of 24 participants, we assessed the risk of CAD associated with HCC and with perceived chronic stress (Perceived Stress Score), controlling for the established risk factors of age, diabetes, hypertension, dyslipidemia, and obesity. In fully adjusted Poisson regression models, we additionally evaluated CAD risk with the simultaneous inclusion of psychological and physiologic resilience measures (CD-RISC, DHEA-S). Our results show that HCC, but not PSS, is significantly associated with CAD (incident rate ratio 0.99, confidence interval 0.98-1.00, p = 0.01), but the magnitude of the association is weak and inverse, and less than with dyslipidemia and age. The association remained significant after inclusion of the sum of resilience measures via a combined resiliency score. Resilience was not independently significantly associated with CAD. Our findings indicate the contribution of HCC to CAD risk is small in an average-risk population and remains after adjustment for multisystem resilience.

Correlates of Mental Health in Adolescents and Young Adults with Cerebral Palsy: A Cross-Sectional Analysis of the MyStory Project

Background: It is important to gain a better understanding of mental health issues in adolescents and young adults (AYA) with cerebral palsy (CP). In this cross-sectional study, we explore if demographics, social and clinical questionnaire scores, and cortisol levels in hair samples from AYA with CP are associated with higher scores on anxiety and/or depression questionnaires. Methods: Data from a community-based sample of 63 AYA with CP (30 females; ages 16 to 30 (median age of 25)) were analyzed. Forty-one (65%) participants (20 females) provided a hair sample. Outcomes were assessed using bivariate linear regression analyses and hierarchical regression analyses. Results: Clinical depressive and anxiety symptoms were present in 33% and 31% of participants, respectively. Family functioning, B = 9.62 (95%CI: 5.49–13.74), fatigue, B = 0.15 (95%CI: 0.05–0.25), and pain, B = 1.53 (95%CI: 0.48–2.58) were statistically significant predictors of depressive symptoms. Fatigue, B = 0.24 (95%CI: 0.12–0.35) and pain, B = 1.63 (95%CI: 0.33–2.94) were statistically significant predictors of anxiety. Cortisol levels from hair samples were not found to be associated with depressive symptoms or anxiety. Conclusions: A high prevalence of mental health problems and co-occurring physical problems was found in AYA with CP. Integrating mental support into regular care for AYA with CP is recommended.

Feasibility of Hair Cortisol as a Biomarker of Chronic Stress in People With Dementia

Hair cortisol concentrations (HCC) are an innovative way to measure chronic stress relying on a small sample of hair. To date, there are no studies that have studied HCC as a biomarker of chronic stress in individuals with dementia. Given the vulnerability to chronic stress in people with dementia, using HCC as an objective measure of physiological stress in those with dementia has potential to enhance our understanding of this population. The goal of this exploratory, multidisciplinary, pilot study was to establish feasibility of HCC testing in people with dementia as a biomarker of chronic stress. HCC was examined over a 6-month period to assess physiological stress response during a transition to memory care. Newly admitted memory care residents ( n = 13, mean age = 82) were followed over 6 months. Residents’ hair samples and health information were collected at 3-month intervals. HCC levels significantly changed during the transition to memory care, which may reflect chronic physiological stress. Participants with frequent behavioral and psychological symptoms of dementia (BPSD) had significantly lower HCC at baseline and exhibited a blunted cortisol reactivity at follow-up. Based on detected changes in HCC, participants likely experienced stress reactions during the transition to memory care, providing preliminary evidence that HCC may be a useful, non-invasive measure of physiological stress in this population. This approach may also be applied to understanding the significance of person-centered care environments on minimizing chronic stress for people with dementia.

Cross-sectional relation of long-term glucocorticoids in hair with anthropometric measurements and their possible determinants: A systematic review and meta-analysis

BACKGROUND

Long-term glucocorticoids (HairGC) measured in scalp hair have been associated with body mass index (BMI), waist circumference (WC), and waist-hip-ratio (WHR) in several cross-sectional studies. We aimed to investigate the magnitude, strength, and clinical relevance of these relations across all ages.

METHODS

We performed a systematic review and meta-analysis (PROSPERO registration CRD42020205187) searching for articles relating HairGC to measures of obesity. Main outcomes were bivariate correlation coefficients and unadjusted simple linear regression coefficients relating hair cortisol (HairF) and hair cortisone (HairE) to BMI, WC, and WHR.

RESULTS

We included k = 146 cohorts (n = 34,342 individuals). HairGC were positively related to all anthropometric measurements. The strongest correlation and largest effect size were seen for HairE-WC: pooled correlation 0.18 (95%CI 0.11-0.24; k = 7; n = 3,158; I²  = 45.7%) and pooled regression coefficient 11.0 cm increase in WC per point increase in 10-log-transformed HairE (pg/mg) on liquid-chromatography-(tandem) mass spectrometry (LC-MS) (95%CI 10.1-11.9 cm; k = 6; n = 3,102). Pooled correlation for HairF-BMI was 0.10 (95%CI 0.08-0.13; k = 122; n = 26,527; I²  = 51.2%) and pooled regression coefficient 0.049 kg/m² per point increase in 10-log-transformed HairF (pg/mg) on LC-MS (95%CI 0.045-0.054 kg/m² ; k = 26; n = 11,635).

DISCUSSION

There is a consistent positive association between HairGC and BMI, WC, and WHR, most prominently and clinically relevant for HairE-WC. These findings overall suggest an altered setpoint of the hypothalamic-pituitary-adrenal axis with increasing central adiposity.

Higher Levels of Stress-Related Hair Steroid Hormones Are Associated with the Increased SCORE2 Risk Prediction Algorithm in Apparently Healthy Women

Cardiovascular diseases (CVDs) are the major cause of death worldwide. Although the importance of conventional CVD risk factors, including older age, male gender, hypertension, obesity, dyslipidemia and hyperglycemia, is well-studied, psychosocial stress, which is considered an independent CVD risk factor, requires further investigation. Thus, we aimed to investigate the association between long-term secretion of stress-related steroid hormones, including cortisol, cortisone and dehydroepiandrosterone, and the 10-year fatal and non-fatal CVD risk estimated by the SCORE2 risk prediction algorithm, as well as traditional CVD risk factors in a group of apparently healthy women. A total of 145 women (aged 50–64 years) participating in the national CVD prevention program were enrolled in the study. Sociodemographic, lifestyle, health-related characteristics, stress, anxiety and sleep quality indicators were evaluated using specific questionnaires. Anthropometric and arterial blood pressure measures were assessed by trained personnel, lipid and glucose metabolism biomarkers were measured using routine methods, and hair steroid hormone levels were determined by ultra-high-performance liquid chromatography-tandem mass spectrometry. The results showed that higher levels of hair cortisol and cortisone are associated with increased SCORE2 values. Moreover, significant associations between hair glucocorticoids and individual cardiovascular risk factors, including obesity, hypertension, dyslipidemia and hyperglycemia, were found. These findings indicate that stress-related hair steroid hormones might be valuable biomarkers for CVD prediction and prevention.

Hair-cortisol and hair-BDNF as biomarkers of tinnitus loudness and distress in chronic tinnitus

The role of stress and its neuroendocrine mediators in tinnitus is unclear. In this study, we measure cortisol as an indicator of hypothalamus–pituitary–adrenal (HPA) axis alterations and brain-derived neurotrophic factor (BDNF) as a marker of adaptive neuroplasticity in hair of chronic tinnitus patients to investigate relationships with tinnitus-related and psychological factors. Cross-sectional data from chronic tinnitus inpatients were analyzed. Data collection included hair sampling, pure tone audiometry, tinnitus pitch and loudness matching, and psychometric questionnaires. Elastic net regressions with n-fold cross-validation were performed for cortisol (N = 91) and BDNF (N = 87). For hair-cortisol (R² = 0.10), the strongest effects were sampling in autumn and body-mass index (BMI) (positive), followed by tinnitus loudness (positive) and smoking (negative). For hair-BDNF (R² = 0.28), the strongest effects were hearing aid use, shift work (positive), and tinnitus loudness (negative), followed by smoking, tinnitus-related distress (Tinnitus Questionnaire), number of experienced traumatic events (negative), and physical health-related quality of life (Short Form-12 Health Survey) (positive). These findings suggest that in chronic tinnitus patients, higher perceived tinnitus loudness is associated with higher hair-cortisol and lower hair-BDNF, and higher tinnitus-related distress with lower hair-BDNF. Regarding hair-BDNF, traumatic experiences appear to have additional stress-related effects, whereas hearing aid use and high physical health-related quality of life appear beneficial. Implications include the potential use of hair-cortisol and hair-BDNF as biomarkers of tinnitus loudness or distress and the need for intensive future research into chronic stress-related HPA axis and neuroplasticity alterations in chronic tinnitus.

The Psychological and Biological Impact of "In-Person" vs. "Virtual" Choir Singing in Children and Adolescents: A Pilot Study Before and After the Acute Phase of the COVID-19 Outbreak in Austria

Psychobiological responses to music have been examined previously in various naturalistic settings in adults. Choir singing seems to be associated with positive psychobiological outcomes in adults. However, evidence on the effectiveness of singing in children and adolescents is sparse. The COVID-19 outbreak is significantly affecting society now and in the future, including how individuals engage with music. The COVID-19 pandemic is occurring at a time when virtual participation in musical experiences such as singing in a virtual choir has become more prevalent. However, it remains unclear whether virtual singing leads to different responses in comparison with in-person singing. We evaluated the psychobiological effects of in-person choral singing (7 weeks, from January to March 2020, before the COVID-19 outbreak) in comparison with the effects of virtual choral singing (7 weeks, from May to July 2020, after schools partly re-opened in Austria) in a naturalistic pilot within-subject study. A group of children and young adolescents (N = 5, age range 10-13, female = 2) from a school in Salzburg, Austria were recruited to take part in the study. Subjective measures (momentary mood, stress) were taken pre- and post-singing sessions once a week. Additionally, salivary biomarkers (cortisol and alpha-amylase) and quantity of social contacts were assessed pre- and post-singing sessions every second week. Psychological stability, self-esteem, emotional competences, and chronic stress levels were measured at the beginning of in-person singing as well as at the beginning and the end of the virtual singing. We observed a positive impact on mood after both in-person and virtual singing. Over time, in-person singing showed a pre-post decrease in salivary cortisol, while virtual singing showed a moderate increase. Moreover, a greater reduction in stress, positive change in calmness, and higher values of social contacts could be observed for the in-person setting compared to the virtual one. In addition, we observed positive changes in psychological stability, maladaptive emotional competences, chronic stress levels, hair cortisol, self-contingency and quality of life. Our preliminary findings suggest that group singing may provide benefits for children and adolescents. In-person singing in particular seems to have a stronger psychobiological effect.

Chronic stress indicated by hair cortisol concentration in anaesthesiologists and its relationship to work experience and emotional intelligence: A cross-sectional biomarker and survey study

BACKGROUND

Anaesthesia is a stressful medical specialty. The reaction to stress is constituted by behavioural, psychological and physiological components. Chronic physiological stress can have negative consequences for health.

OBJECTIVES

First, we hypothesised that chronic physiological stress is higher for both beginning and late-career consultant anaesthesiologists. Second, we hypothesised that individuals high in emotional intelligence endure lower physiological stress.

DESIGN

Cross-sectional biomarker and survey study.

SETTING

Participants were recruited during the May 2019 annual meeting of the Dutch Anaesthesia Society.

PARTICIPANTS

Of the 1348 colleagues who attended the meeting, 184 (70 male/114 female) participated in the study. Of the study participants, 123 (67%) were consultant anaesthesiologists (52 male/71 female) and 61 (33%) were resident anaesthesiologists (18 male/43 female). Exclusion criteria were endocrine disorders and not having enough hair. Also, experience of a recent major life event led to exclusion from analysis of our hypotheses.

MAIN OUTCOME MEASURES

Chronic physiological stress was measured by hair cortisol concentration. Emotional intelligence was assessed using a validated Dutch version of the Trait Emotional Intelligence Questionnaire. As secondary measures, psychological sources of stress were assessed using validated Dutch versions of the home-work interference (SWING) and the effort-reward imbalance questionnaires.

RESULTS

In support of Hypothesis 1, hair cortisol concentration was highest among early and late-career consultant anaesthesiologists (quadratic effect: b = 45.5, SE = 16.1, t = 2.8, P = 0.006, R2 = 0.14). This nonlinear pattern was not mirrored by self-reported sources of psychological stress. Our results did not support Hypothesis 2; we found no evidence for a relationship between emotional intelligence and physiological stress.

CONCLUSION

In the early and later phases of an anaesthesiologist's career, physiological chronic stress is higher than in the middle of the career. However, this physiological response could not be explained from known sources of psychological stress. We discuss these findings against the background of key differences between physiological and psychological stress.

Predicting Hair Cortisol and Cortisone Concentration in Postpartum Women through Repeated Measurements of Perceived Stress

To investigate whether hair cortisol (HCC) and hair cortisone (HCNC) can be predicted by repeated stress reports from postpartum women in different mental health conditions (non-depressed, ND, adjustment disorder, AD, postpartum depression, PPD), 240 mothers (mean age 31.8 years; SD = 4.7) were monitored from within 1 to 6 days of childbirth over a period of three months. HCC and HCNC in 3 cm hair samples were assessed via triple mass spectrometry after liquid chromatographic separation. Every second day, participants reported their stress levels online. The summed perceived stress scores were not found to be predictive of HCC. However, perceived stress predicted a decrease in HCNC (r_Spearman = -0.153, p = 0.035) and an increase in the HCC/HCNC ratio (r_Spearman = 0.304, p < 0.001) in the ND group. With AD in the first few weeks after childbirth, an inverse effect appeared for HCNC (r_Spearman = 0.318, p = 0.011), suggesting an overall downregulation of the HPA axis owing to the stressful experience of adjusting to the new situation. No effects were found for mothers developing PPD. The indirect results of HPA-axis activity are better indicators of the experience of psychological stress in postpartum women than the absolute HCC value.

The Association between Endogenous Hair Steroid Hormones and Social Environmental Factors in a Group of Conscripts during Basic Military Training

This study aimed to analyse the association between endogenous hair steroid hormones as reliable biological indicators of an individual’s stress level and the social environmental factors experienced during military training that are manifested at the beginning of compulsory military service. Hair steroid hormone concentrations—cortisol, cortisone, dehydroepiandrosterone (DHEA), and testosterone—in a group of 185 conscripts were measured using the ultra-high performance liquid chromatography-tandem mass spectrometry method. Six subjective social environmental factors in the military—attitude towards the military and military service, adaptation to the military environment, team, task, and norm cohesion, as well as psychological (un)safety in the group—were evaluated using military-specific research questionnaires. Weak but significant negative correlations were identified between cortisol and adaptation (r = −0.176, p < 0.05), attitude (r = −0.147, p < 0.05) as well as between testosterone and task cohesion (r = −0.230, p < 0.01) levels. Additionally, a multiple forward stepwise regression analysis highlighted that cortisone variation might be partially explained by task cohesion; the DHEA—determined by psychological (un)safety in the group, attitude towards the military and military service, and norm cohesion; and the testosterone—determined by task cohesion and adaptation to the new military environment. The results of this study suggest that subjective measures of social factors can be used to predict hair steroid hormone levels as objective measures of the chronic stress perceived by conscripts during their basic military training.

The association between chronic stress, hair cortisol, and angiographically documented coronary atherosclerosis, a case-control study

Cardiovascular diseases remain the principal contributor to global mortality and morbidity. Chronic stress has emerged as a strong prognostic factor for cardiovascular diseases. We aimed to measure hair cortisol concentration (HCC) in patients with angiographically confirmed coronary atherosclerosis and find the association between HCC and classic cardiovascular risk factors in a case-control study. The study included 500 angiographically confirmed coronary atherosclerosis patients and 500 age and sex-matched controls having no coronary stenosis. Hair cortisol concentration was assessed from a single sample of scalp hair by ELISA. Perceived stress scale 10 was used to evaluate the stress level of the participants. Spearman rank correlation was applied to find the association between hair cortisol level and classic cardiovascular risk factors. Multivariate regression was executed to assess the independent contribution of hair cortisol concentration as a coronary atherosclerosis risk factor. Median hair cortisol concentration was significantly high in patients with angiographically documented coronary atherosclerosis compared to controls (158(17.6-1331.3) pg/mg versus 73 (13.4-889) pg/mg. Hair cortisol concentration showed a significant positive correlation with BMI r = 525 and Hb1Ac r = 665 (both, p = ≤0.0001). In multivariate logistic regression analysis after adjusting for all the confounding variables, HCC, matched odds ratio (MOR), 10.73;95%CI (1.60,42.09) p-value = 0.001 remained the most significant predictor of coronary atherosclerosis.LAY SUMMARYHair cortisol concentrations (HCC) were significantly high in patients with angiographically confirmed coronary atherosclerosis compared to controls. HCC showed a significant positive correlation with diabetes and obesity and remained a major predictor of coronary atherosclerosis in the final analysis.

Sex-specific association of hair cortisol concentration with stress-related psychological factors in healthy young adults

BACKGROUND

Hair cortisol concentration (HCC) has received attention as a useful marker of stress, but evidence on associations between psychological factors and cortisol concentration is inconsistent. The purpose of this study was to investigate the sex differences in the relationship between cortisol concentration and psychological factors in healthy young adults.

METHODS

A total of 205 (103 females, 102 males) healthy young adults participated. HCC and various stress-related psychological measures were compared between sexes. Multiple linear regression analyses were performed to assess associations between HCC and stress-related psychological measures for all participants and for each sex.

RESULTS

The difference in HCC according to sex was not significant. The reported number of stressful life events in the past year, stress perception, depressive and anxiety-related symptoms, and emotion dysregulation were not different between sexes, either. The association between HCC and emotion dysregulation was significant in females but not males.

CONCLUSION

We observed a sex-specific association between HCC and psychological factors. Our findings may imply that HCC could be a useful biomarker of stress and stress-related emotion dysregulation in healthy young women.

Urinary Polycyclic Aromatic Hydrocarbon Metabolites Are Associated with Biomarkers of Chronic Endocrine Stress, Oxidative Stress, and Inflammation in Adolescents: FLEHS-4 (2016-2020)

Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants of public health concern. Multiple biological mechanisms have been hypothesized to contribute to PAHs-associated adverse health effects. Little is known about the impact of PAHs on endocrine stress and inflammation in adolescence. We examined 393 Flemish adolescents (14-15 years) cross-sectionally, measured urinary concentrations of hydroxylated naphthalene, fluorene, phenanthrene and pyrene metabolites, and calculated the sum of all measured metabolites. We determined hair cortisol concentration (HCC) as endocrine stress biomarker, leucocyte counts and neutrophil-lymphocyte ratio (NLR) in peripheral blood as inflammatory biomarkers, and urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) concentration as oxidative stress biomarker. Exposure-response associations were analyzed by multiple regression, adjusted for a priori selected covariates. A doubling of 1-hydroxypyrene concentration was associated with a factor of 1.13 (95% CI: 1.03, 1.24) increase in HCC and a factor of 1.07 (95% CI: 1.02, 1.13) increase in 8-oxodG. Doublings of 2- and 3-hydroxyphenanthrene concentrations were associated with a factor of 1.08 (95% CI: 1.02, 1.14) and 1.06 (95% CI: 1.00, 1.12) increase in 8-oxodG, respectively. Doubling of 2-hydroxyphenanthrene and of the sum of 2- and 3-hydroxyfluorene was associated with, respectively, a factor of 1.08 (95% CI: 1.02, 1.14) and 1.06 (95% CI: 1.01, 1.13) increase in NLR. Our results indicate the glucocorticoid pathway as a potential target for PAH exposure in adolescents and suggest oxidative stress, endocrine stress, and inflammation in adolescence as underlying mechanisms and early markers for PAH-related adverse health effects.

Hair cortisol, obesity and the immune system: Results from a 3 year longitudinal study

OBJECTIVES

Higher long-term glucocorticoid levels, measured in scalp hair (HairGC), are associated with obesity. This may represent the state of obesity (perhaps interrelated with chronic immune activation), but could also promote further weight gain. We studied whether hair cortisol (HairF) and hair cortisone (HairE) predict changes in body mass index (BMI) and waist circumference (WC) over time, and assessed the association between HairGC and common immune parameters.

METHODS

We measured HairGC in 1604 participants of the Netherlands Study of Depression and Anxiety (NESDA), and investigated their associations to BMI, WC, and immune parameters (interleukin-6 (IL-6), C-reactive protein (CRP), and leukocyte subsets). Also, we assessed whether baseline HairGC predict changes in BMI and WC at follow-up (three years later).

RESULTS

In cross-sectional analyses, HairF and HairE were positively associated to BMI (β = 2.06 kg/m2, 95% confidence interval (CI)= 1.22-2.90 kg/m2) and β = 2.84 kg/m2 (95%CI 1.75-3.93 kg/m2) respectively) and WC (β = 5.36 cm (95%CI 3.09-7.62 cm) and β = 8.54 cm (95%CI 5.60-11.48 cm) respectively, all p < 0.001). HairF was also positively associated to IL-6 (β = 0.15 (95%CI 0.003-0.292) p < 0.05) and leukocyte count (β = 0.57 (95%CI 0.234-0.909), p < 0.01), and HairE to IL-6 (β = 0.21 (95%CI 0.016-0.399), p < 0.05). In the longitudinal analyses, higher HairF was associated with yearly increases in BMI (β = 0.58% BMI change per year (95%CI 0.14-1.01%), p = 0.009) and higher HairE with increases in WC (β = 0.84% WC change per year (95%CI 0.02-1.69%), p = 0.049). Adjusting for baseline IL-6 or leukocytes did not change the found associations between HairGC and WC or BMI change.

CONCLUSIONS

HairGC levels are positively associated to BMI, WC, IL-6 and leukocyte numbers in cross-sectional analyses, and to increases in BMI and WC in longitudinal analyses. Although causality is yet to be proven, higher long-term glucocorticoid levels could represent a relevant risk factor for the development of obesity.

Associations between hair and salivary cortisol, salivary alpha-amylase, and temperament dimensions among 3-6-year-olds

Associations between hair cortisol concentration (HCC), diurnal salivary cortisol (sCort) and alpha-amylase (sAA), and temperament dimensions were examined among 3-6-year-old Finnish children (n = 833). Children's hair samples were collected at preschool, while parents collected five saliva samples from children during one weekend day and completed a questionnaire assessing child's temperament dimensions i.e. surgency, negative affectivity, and effortful control (HCC, n = 677; AUCg of sAA, n = 380; AUCg of sCort, n = 302; temperament dimensions, n = 751). In linear regression analysis, diurnal sCort associated positively with HCC, the association persisting after adjustments (β 0.31, 95% CI 0.20-0.42). In logistic regression analysis, increasing scores in effortful control associated with higher likelihood of having high HCC (OR 1.47, 95% CI 1.07-2.03), the association slightly attenuating to non-significant after adjustments. Otherwise, no clear indication for associations between temperament and stress-related biomarkers were found.

Parental Stress and Scalp Hair Cortisol in Excessively Crying Infants: A Case Control Study

BACKGROUND

Caring for an excessively crying infant (ECI) can be stressful for mothers and fathers and is associated with mental and bonding problems. Hair cortisol offers a unique measure for the biological reaction of the body to stress over time.

METHODS

In this case-control study, scalp hair cortisol concentrations (HCC) were measured using liquid chromatography-tandem mass spectrometry (LC-MS) in 35 mothers and 23 fathers and their ECIs. The control group consisted of 64 mothers and 63 fathers of non-ECIs of similar age. Parental stress, depression, anxiety and bonding were assessed using validated questionnaires.

RESULTS

Mean HCC were significantly lower in mothers and fathers of ECIs (2.3 pg/mg, 95% CI 1.8-2.9 and 1.6 pg/mg, 95% CI 1.3-2.0) than that in control mothers and fathers (3.2 pg/mg, 95% CI 3.0-3.7 and 2.9 pg/mg, 95% CI 2.5-3.5). In the total group of parents and within the parents of ECIs, HCC were not associated with negative feelings. In the control group, HCC showed a positive association with stress and depression (r = 0.207, p = 0.020 and r = 0.221, p = 0.013). In infants, no differences were found in mean HCC between the ECI group and the control group. No associations were found between maternal and infant HCC, paternal and infant HCC and maternal and paternal HCC.

CONCLUSION

Parents of ECIs showed significantly lower HCC than control parents, reflecting a diminished response of the hypothalamic-pituitary-adrenal (HPA) axis. More research is needed to examine whether this decrease in response is pre-existing or caused by excessive infant crying.

Hormone seasonality in medical records suggests circannual endocrine circuits

We provide a dataset of millions of hormone tests from medical records that shows seasonality with a winter−spring peak in hormones for reproduction, growth, metabolism, and stress adaptation. Together with a long history of studies on a winter−spring peak in human function and growth, the hormone seasonality indicates that, like other animals, humans may have a physiological peak season for basic biological functions. We further use the specific seasonal phases of the hormones to suggest a model for a circannual clock in humans and animals that can keep track of the seasons, similar in spirit to the circadian clock that keeps track of time of day.

Hormones control the major biological functions of stress response, growth, metabolism, and reproduction. In animals, these hormones show pronounced seasonality, with different set-points for different seasons. In humans, the seasonality of these hormones remains unclear, due to a lack of datasets large enough to discern common patterns and cover all hormones. Here, we analyze an Israeli health record on 46 million person-years, including millions of hormone blood tests. We find clear seasonal patterns: The effector hormones peak in winter−spring, whereas most of their upstream regulating pituitary hormones peak only months later, in summer. This delay of months is unexpected because known delays in the hormone circuits last hours. We explain the precise delays and amplitudes by proposing and testing a mechanism for the circannual clock: The gland masses grow with a timescale of months due to trophic effects of the hormones, generating a feedback circuit with a natural frequency of about a year that can entrain to the seasons. Thus, humans may show coordinated seasonal set-points with a winter−spring peak in the growth, stress, metabolism, and reproduction axes.

Salivary biomarkers of stress and inflammation in first graders in Côte d'Ivoire: Effects of a probiotic food intervention

This semi-randomized controlled trial examined the effects of a probiotic food supplement on cortisol and C-reactive protein (CRP) in a sample of 262 four-to seven-year-old children (56% girls) in two economically-disadvantaged schools in an urban setting in Côte d'Ivoire. For one semester, children in one school were randomized to receive a probiotic (N = 79) or placebo (N = 85) fermented dairy food each day they attended school; one child (due to medical reasons) and all children in the other school (N = 98) continued their diets as usual. Children provided two saliva samples at 11:30 on consecutive days at the end of the study. Analyses revealed that the probiotic group had lower cortisol than the placebo or diet-as-usual groups (p = .015); CRP levels were comparable across groups (p = .549). Exploratory analyses suggested that dose and regularity of consumption may impact the biomarkers as well. This study provides the first evidence that a probiotic milk product may lower cortisol in a sample of young, economically-disadvantaged children.

Hair cortisol in mother-child dyads: examining the roles of maternal parenting and stress in the context of early childhood adversity

Physiological stress is thought to be one way that early adversity may impact children's health. How this occurs may be related to parental factors such as mothers' own stress and parenting behaviour. Hair cortisol offers a novel method for examining long-term physiological stress in mother-child dyads. The current study used hair cortisol to examine the role that maternal physiological stress and parenting behaviours play in explaining any effects of adversity on young children's physiological stress. This cross-sectional study comprised 603 mother-child dyads at child age 2 years, recruited during pregnancy for their experience of adversity through an Australian nurse home visiting trial. Hair cortisol data were available for 438 participating mothers (73%) and 319 (53%) children. Confirmatory factor analysis was used to define composite exposures of economic (e.g. unemployment, financial hardship) and psychosocial (e.g. poor mental health, family violence) adversity, and positive maternal parenting behaviour (e.g. warm, responsive). Structural equation modelling examined maternal mediating pathways through which adversity was associated with children's physiological stress. Results of the structural model showed that higher maternal and child physiological stress (hair cortisol) were positively associated with one another. Parenting behaviour was not associated with children's physiological stress. There was no evidence of any mediating pathways by which economic or psychosocial adversity were associated with children's physiological stress. The independent association identified between maternal and child hair cortisol suggests that young children's physiological stress may not be determined by exogenous environmental exposures; endogenous genetic factors may play a greater role.

Hair Cortisol Concentration and Perceived Chronic Stress in Low-Income Urban Pregnant and Postpartum Black Women

Black women are more likely to experience short- or long-term health consequences from their labor and delivery and die from pregnancy-related causes than White women. Similarly, infants born to Black women also have heightened health risks. Developing research suggests that a contributing factor to Black health disparities may be maternal chronic stress. A widely used biomarker for chronic stress is hair cortisol concentration (HCC). Few prior studies have explored the HCC of pregnant Black women or comprehensively examined perceived chronic stress in this population. Using a mixed-methods focus group framework, we assessed HCC and perceived chronic stress among low-income pregnant and postpartum Black women. Four focus groups were conducted (N = 24). The mean HCC for our pregnant Black participants was greater than pregnant White women in reviewed published studies. The high levels of stress evidenced at all pregnancy stages indicate that many of these women are experiencing chronic stress, which can contribute to higher Black maternal morbidity and mortality rates, and possibly infant mortality rates. From the open coding of the focus group transcripts, 4 themes emerged: chronic stress, experiences of racism, experiences of trauma, and negative thinking. Selective coding based on these themes revealed cumulative experiences of chronic stress, various traumatic experiences, and frequent encounters with racism. Negative thinking styles were observed across the 4 focus groups. More studies of HCC and perceived stress among pregnant Black women are encouraged. Findings suggest the need for tailored multi-level interventions given the layers of stressors present in this population.

The Relation between Hair-Cortisol Concentration and Various Welfare Assessments of Dutch Dairy Farms

Many protocols have been developed to assess farm animal welfare. However, the validity of these protocols is still subject to debate. The present study aimed to compare nine welfare assessment protocols, namely: (1) Welfare Quality^© (WQ), (2) a modified version of Welfare Quality (WQ Mod), which has a better discriminative power, (3) WelzijnsWijzer (Welfare Indicator; WW), (4) a new Welfare Monitor (WM), (5) Continue Welzijns Monitor (Continuous Welfare Monitor; CWM), (6) KoeKompas (Cow Compass; KK), (7) Cow Comfort Scoring System (CCSS), (8) Stall Standing Index (SSI) and (9) a Welfare Index (WI Tuyttens). In addition, a simple welfare estimation by veterinarians (Estimate vets, EV) was added. Rank correlation coefficients were calculated between each of the welfare assessment protocol scores and mean hair cortisol concentrations from 10 cows at 58 dairy farms spread over the Netherlands. Because it has been suggested that the hair cortisol level is related to stress, experienced over a long period of time, we expected a negative correlation between cortisol and the result of the welfare protocol scores. Only the simple welfare estimation by veterinarians (EV) (ρ = -0.28) had a poor, but significant, negative correlation with hair cortisol. This correlations, however, failed to reach significance after correction of p-values for multiple correlations. Most of the results of the different welfare assessment protocols had a poor, fair or strong positive correlation with each other, supporting the notion that they measure something similar. Additional analyses revealed that the modified Welfare Quality protocol parameters housing (ρ = -0.30), the new Welfare Monitor (WM) parameter health (ρ = -0.33), and milk yield (ρ = -0.33) showed negative correlations with cortisol. We conclude that because only five out of all the parameter scores from the welfare assessment protocols showed a negative, albeit weak, correlation with cortisol, hair cortisol levels may not provide a long term indicator for stress in dairy cattle, or alternatively, that the protocols might not yield valid indices for cow welfare.

Examining longitudinal associations between self-reported depression, anxiety and stress symptoms and hair cortisol among mothers of young children

BACKGROUND

Maternal mental health is critically important given its impacts on both women's and children's outcomes. Hair cortisol concentrations (HCC) may provide insight into physiological processes underpinning mental health. This study investigated associations between mothers' self-reported mental health symptoms and their HCC at 1, 2 and 3 years postpartum.

METHODS

Longitudinal study of Australian mothers recruited for their experience of adversity in pregnancy ('right@home' trial, N=722). Mental health symptoms were self-reported using the Depression, Anxiety and Stress Scales (DASS). Associations between DASS total and subscale scores and HCC were estimated using linear regression and generalized estimating equation (GEE) models, examining associations: at each age; across all ages (multivariate GEE); and with persistence of high symptom severity. Missing data were addressed using multiple imputation.

RESULTS

546/722 (76%) women provided at least one hair sample (71% at 1, 61% at 2, 49% at 3 years). Associations between DASS total or subscale scores and HCC were not evident across time points. Only dichotomized high depression symptom severity was associated with higher HCC in the GEE models (β=0.12, p=0.04). There was no evidence of associations between persistence of high DASS symptom severity and HCC at 3 years.

LIMITATIONS

The DASS measured self-reported symptoms for the preceding week whereas HCC captured average cortisol over three months. Associations amongst mothers experiencing adversity may not represent patterns in the general population.

CONCLUSIONS

Considered in context with existing literature, these findings suggest that HCC provides limited insight into the mental health of mothers experiencing adversity across the early postpartum years.

Residential exposure to air pollution and access to neighborhood greenspace in relation to hair cortisol concentrations during the second and third trimester of pregnancy

BACKGROUND

Exposure to air pollution during pregnancy has been associated with adverse pregnancy outcomes in studies worldwide, other studies have described beneficial effects of residential greenspace on pregnancy outcomes. The biological mechanisms that underlie these associations are incompletely understood. A biological stress response, which implies release of cortisol, may underlie associations of air pollution exposure and access to neighborhood greenspaces with health.

METHODS

We explored residential exposure to air pollution and residential access to neighborhood greenspaces in relation to hair cortisol concentrations of participants in a prospective pregnancy cohort study in Flanders, Belgium. Hair samples were collected at the end of the second pregnancy trimester (n = 133) and shortly after delivery (n = 81). Cortisol concentrations were measured in 3-cm scalp-near hair sections, to reflect second and third pregnancy trimester cortisol secretion. We estimated long-term (3 months before sampling) residential exposure to fine particulate matter (PM_2.5), nitrogen dioxide (NO₂) and black carbon (BC), assessed residential distance to major roads and residential access to neighborhood greenspaces (NHGS). Associations between residential exposures and hair cortisol concentrations were studied using linear regression models while adjusting for season of sampling.

RESULTS

Three-month mean residential NO₂ and BC concentrations were positively associated with third pregnancy trimester hair cortisol concentrations (p = 0.008 and p = 0.017). Access to a large NHGS (10 ha or more within 800 m from residence) was negatively associated with third trimester hair cortisol concentrations (p = 0.019). Access to a large NHGS significantly moderated the association between residential proximity to major roads and second trimester hair cortisol concentrations (p = 0.021). Residential distance to major roads was negatively associated with second trimester hair cortisol concentrations of participants without access to a large NHGS (p = 0.003). The association was not significant for participants with access to a large NHGS. The moderation tended towards significance in the third pregnancy trimester (p < 0.10).

CONCLUSIONS

Our findings suggest a positive association between long-term residential exposure to air pollution and biological stress during pregnancy, residential access to neighborhood greenspaces may moderate the association. Further research is needed to confirm our results.

TRIAL REGISTRATION

The IPANEMA study is registered under number  NCT02592005 at clinicaltrials.gov .