Hair Cortisol Concentration as a Biomarker of Sleep Quality and Related Disorders

Road traffic noise exposure and its impact on health: evidence from animal and human studies-chronic stress, inflammation, and oxidative stress as key components of the complex downstream pathway underlying noise-induced non-auditory health effects

In heavily urbanized world saturated with environmental pollutants, road traffic noise stands out as a significant factor contributing to widespread public health issues. It contributes in the development of a diverse range of non-communicable diseases, such as cardiovascular diseases, metabolic dysregulation, cognitive impairment, and neurodegenerative disorders. Although the exact mechanisms behind these non-auditory health effects remain unclear, the noise reaction model centres on the stress response to noise. When exposed to noise, the body activates the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system, leading to the secretion of stress hormones like catecholamines and cortisol. Prolonged exposure to noise-induced stress results in chronic inflammation and oxidative stress. This review underscores the role of inflammation and oxidative stress in the progression of noise-induced vascular dysfunction, disruption of the circadian rhythm, accelerated aging, neuroinflammation, and changes in microbiome. Additionally, our focus is on understanding the interconnected nature of these health outcomes: These interconnected factors create a cascade effect, contributing to the accumulation of multiple risk factors that ultimately lead to severe adverse health effects.

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.

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

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

Hair cortisol concentration associates with insomnia and stress symptoms in breast cancer survivors

Stress, depressive symptoms and sleep quality are important and modifiable determinant of health and their association with hair cortisol concentrations (HCC) in breast cancer survivors has not been evaluated. We selected a random sample of 65 participants (mean age 57.9 years old, range 44-75 years) recruited from local patients' associations of breast cancer survivors. Each provided a hair sample at enrollment and basic clinical data and psychological evaluation regarding self-perceived stress (PSS-scale), depressive (GDS scale) and insomnia symptoms (Athens scale). We observed a direct and significant (p = 0.001) association between HCC and stress-levels. Depressive symptoms associated significantly (p < 0.01) with stress levels but not with HCC. There were also a significant and direct correlation between hair cortisol concentration and totals core of insomnia symptoms (p = 0.002), and the subdimension of sleep difficulty symptoms (p = 0.002), and with daytime sleepiness symptoms (p = 0.016). Further investigations into the association between stress and insomnia and changes in HCC in breast cancer survivors are warranted in order to validate this biomarker for diagnosis of psychological alterations and to tailor the effects of interventions aimed to reduced stress and improve sleep quality in these women.

Association of hair glucocorticoid levels with sleep quality indicators: a pilot study in apparently healthy perimenopausal and menopausal women

Background

Poor sleep quality is associated with different physical and mental health diseases. It is proposed that increased hypothalamic-pituitary-adrenal axis activity is a potential contributor affecting sleep pattern and quality. We aimed to analyze the relationship between subjective sleep quality indicators and hair glucocorticoid levels among relatively healthy perimenopausal and postmenopausal women.

Methods

A total of 145 women aged 50-64 y.o. were enrolled in the cross-sectional pilot study. Sleep quality was evaluated using the Pittsburgh Sleep Quality Index, while stress level was measured using the Perceived Stress Scale. Hair cortisol and cortisone levels were determined by ultra-high-performance liquid chromatography-tandem mass spectrometry.

Results

Statistically significant positive relationship was found between hair cortisol concentration and Pittsburgh sleep quality index score. Similarly, statistically significant positive associations were observed between hair total glucocorticoid level and Pittsburgh sleep quality index, sleep disturbance, and Perceived Stress Scale scores. Subjects with prolonged sleep latency had significantly higher hair cortisol and total hair glucocorticoid concentrations compared with individuals whose sleep latency is not disturbed. Additionally, Chi-squared test indicated that lower hair cortisol concentration was significantly related to better sleep efficiency.

Conclusion

Increased hair glucocorticoid (cortisol, cortisone) levels were found to be related with worse sleep quality measured by Pittsburgh sleep quality index score.

Preconception sleep quality moderates the association between preconception hair cortisol levels and mental health in pregnant women

BACKGROUND

Poor sleep quality may elevate cortisol levels and affect prenatal mental health through altered HPA axis functioning. This study aims to examine whether subjective sleep quality during preconception moderates the association between preconception hair cortisol levels and mental health from preconception to pregnancy trimesters.

METHODS

Women from a prospective cohort study completed the Pittsburgh Sleep Quality Index (PSQI), the Edinburgh Postnatal Depression Scale (EPDS), and the State-Trait Anxiety Inventory (STAI) questionnaires during preconception (T0) and at each pregnancy trimesters (T1, T2, and T3). We analyzed 266 of these women who conceived and had fully completed measures at preconception for hair cortisol, sleep quality and either EPDS or STAI-state. Changes in EPDS and STAI-state scores were derived (i.e., T1-T0, T2-T0, T3-T0). Johnson-Neyman technique identified PSQI scores with significant moderation of cortisol on mental health.

RESULTS

After adjusting for potential covariates, there was a significant positive correlation between preconception hair cortisol levels and depressive symptom at the second trimester (r_s (144) = 0.22, p = 0.008), but not the first and third trimesters (all p_s > 0.05). The positive association between preconception hair cortisol and change in depressive symptoms between third trimester and preconception was significant only among women with poor preconception sleep quality (PSQI ≥ 7).

LIMITATIONS

Sleep quality and prenatal mood were derived from self-reported questionnaires, which may be more susceptible to bias.

CONCLUSIONS

The positive association between preconception hair cortisol and change in prenatal depressive symptoms is significant among women who reported poor sleep quality during preconception. Improving preconception sleep quality can potentially mitigate the association between preconception hair cortisol and depressive symptoms during pregnancy.

The Queensland Twin Adolescent Brain Project, a longitudinal study of adolescent brain development

We describe the Queensland Twin Adolescent Brain (QTAB) dataset and provide a detailed methodology and technical validation to facilitate data usage. The QTAB dataset comprises multimodal neuroimaging, as well as cognitive and mental health data collected in adolescent twins over two sessions (session 1: N = 422, age 9-14 years; session 2: N = 304, 10-16 years). The MRI protocol consisted of T1-weighted (MP2RAGE), T2-weighted, FLAIR, high-resolution TSE, SWI, resting-state fMRI, DWI, and ASL scans. Two fMRI tasks were added in session 2: an emotional conflict task and a passive movie-watching task. Outside of the scanner, we assessed cognitive function using standardised tests. We also obtained self-reports of symptoms for anxiety and depression, perceived stress, sleepiness, pubertal development measures, and risk and protective factors. We additionally collected several biological samples for genomic and metagenomic analysis. The QTAB project was established to promote health-related research in adolescence.

Analysis of the determinants of sleep quality in a Spanish population: a study protocol for a cross-sectional study

INTRODUCTION

Sleep problems are a growing public health concern being related, among others, to an increased risk of cardiovascular diseases or worse cognitive functioning. In addition, they can affect aspects related to personal motivation and quality of life. However, very few studies have analysed the possible determinants of sleep quality in the adult population as a whole, establishing patterns based on these determinants.The objectives are to evaluate the determinants of sleep quality in a representative sample of the general adult population between 25 and 65 years old, and to establish patterns of sleep quality based on lifestyles, psychological factors, morbidities, sociodemographic variables, biological markers and other possible determinants.

METHODS AND ANALYSIS

Descriptive observational cross-sectional study. The study population will include a representative sample of 500 people between 25 and 65 years old from the cities of Salamanca and Ávila (Spain) selected by random sampling stratified by age groups and sex. A 90-minute visit will be performed, during which sleep quality will be assessed. The variables collected will be: morbidity, lifestyles (physical activity, diet, toxic habits), psychological factors (depression, stress, occupational stress and anxiety), socioeconomic and work-related variables, habitability conditions of the habitual residence and rest area, screen time, relaxation techniques and melatonin as a biological marker related to sleep quality.

DISCUSSION

With the results of this work, improved interventions for behaviour modification could be designed, as well as intervention and education programmes or other research aimed at improving sleep quality.

ETHICS AND DISSEMINATION

This study has a favourable opinion from the Ethics Committee for Drug Research of the Health Areas of Salamanca and Ávila (CEim Code: PI 2021 07 815). The results of this study will be published in international impact journals of different specialties.

TRIAL REGISTRATION NUMBER

NCT05324267.

Sleep Disturbances in Generalized Anxiety Disorder: The Role of Calcium Homeostasis Imbalance

Patients with a generalized anxiety disorder (GAD) often report preeminent sleep disturbances. Recently, calcium homeostasis gained interest because of its role in the regulation of sleep-wake rhythms and anxiety symptoms. This cross-sectional study aimed at investigating the association between calcium homeostasis imbalance, anxiety, and quality of sleep in patients with GAD. A total of 211 patients were assessed using the Hamilton Rating Scale for Anxiety (HAM-A), Pittsburgh Sleep Quality Index questionnaire (PSQI) and Insomnia Severity Index (ISI) scales. Calcium, vitamin D, and parathyroid hormone (PTH) levels were evaluated in blood samples. A correlation and linear regression analysis were run to evaluate the association of HAM-A, PSQI, and ISI scores with peripheral markers of calcium homeostasis imbalance. Significant correlations emerged between HAM-A, PSQI, ISI, PTH, and vitamin D. The regression models showed that patients with GAD displaying low levels of vitamin D and higher levels of PTH exhibit a poor subjective quality of sleep and higher levels of anxiety, underpinning higher psychopathological burden. A strong relationship between peripheral biomarkers of calcium homeostasis imbalance, insomnia, poor sleep quality, and anxiety symptomatology was underlined. Future studies could shed light on the causal and temporal relationship between calcium metabolism imbalance, anxiety, and sleep.

Hair cortisol as a viable tool for the assessment of an association between environmental noise exposure and chronic stress

Entrenched in the well-established link between stress and health, noise exposure as a potential contributor to stress-related health effects receives tremendous attention. Indeed, exposure to noise can act as a stressor as evidenced through increased heart rate, blood pressure, adrenaline, epinephrine, and cortisol. Cortisol is secreted from the adrenal glands in response to stressor-induced activation of the hypothalamic-pituitary-adrenal axis. For assessment of environmental noise and stress, repeated sampling in blood, saliva, or urine is necessary to evaluate the association between environmental noise exposure and protracted changes in cortisol. Controlling for the many variables that influence the secretion of cortisol at discrete sampling intervals is challenging. Studies suggest that systemically produced cortisol integrates and remains in hair as it grows, providing a measure that integrates a cortisol response over a longer period, circumventing several limitations associated with multiple sampling. Robust evidence supports the integration of cortisol into hair, yet recent studies call into question the notion that cortisol is retained with growth. The current paper discusses the strengths and limitations of hair cortisol analysis with an emphasis on its utility as a measure of chronic stress in environmental noise studies.

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.

Roles of clock genes in the pathogenesis of Parkinson's disease

Parkinson's disease (PD) is a common motor disorder that has become increasingly prevalent in the ageing population. Recent works have suggested that circadian rhythms disruption is a common event in PD patients. Clock genes regulate the circadian rhythm of biological processes in eukaryotic organisms, but their roles in PD remain unclear. Despite this, several lines of evidence point to the possibility that clock genes may have a significant impact on the development and progression of the disease. This review aims to consolidate recent understanding of the roles of clock genes in PD. We first summarized the findings of clock gene expression and epigenetic analyses in PD patients and animal models. We also discussed the potential contributory role of clock gene variants in the development of PD and/or its symptoms. We further reviewed the mechanisms by which clock genes affect mitochondrial dynamics as well as the rhythmic synthesis and secretion of endocrine hormones, the impairment of which may contribute to the development of PD. Finally, we discussed the limitations of the currently available studies, and suggested future potential studies to deepen our understanding of the roles of clock genes in PD pathogenesis.

Split-Second Unlearning: Developing a Theory of Psychophysiological Dis-ease

Psychophysiological “stress” underpins many conditions including anxiety, depression, phobias, chronic fatigue syndrome and non-specific musculoskeletal pain such as fibromyalgia. In this article we develop an understanding of chronic psychophysiological stress from a psychological educational perspective, by drawing on supporting evidence that significant emotional events in early life (traumatic and benign) can influence health and well-being later in life. We suggest that traumatic events instigate psychophysiological “stress” responses and the formation of emotional memory images (EMIs) within very short time frames, i.e., “split-second learning.” Once formed these emotional memories are triggered in daily living “re-playing” psychophysiological stress responses, resulting in chronic psychophysiological “dis-ease.” We describe a novel therapeutic approach to scan clients for mannerisms signifying a subconscious “freeze-like” stress response that involves the client as a curious observer within their own experience, feeding back the non-verbal cues as they arrive in the moment. By breaking down the observable fragments of their split-second Pavlovian response to the trigger, clients can detach their EMI from the psychophysiology stress response, i.e., “split-second unlearning.” Our split-second unlearning model recognizes the EMI as a barrier to moving forward and needs to be unlearned before the client can become naturally adaptive again. We argue that this approach places the client at the center of the work without the need of getting bogged down in a life-long narrative.

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.