Comparative analysis of salivary cortisol measurements using different assay methods in relation to serum-free cortisol measurement

Objectives

Salivary cortisol reflects the biologically active form of serum cortisol, offering a noninvasive evaluation method for the diurnal rhythm of the hypothalamic-pituitary-adrenal (HPA) axis. While liquid chromatography-tandem mass spectrometry (LC-MS/MS) is known for its specificity, immunoassays (IA) are commonly used because of their simplicity. This study aimed to assess the performance of salivary cortisol measurement using both IA and LC-MS/MS in comparison to serum-free cortisol measurement.

Methods

Assay results for 188 saliva and 94 serum samples from 47 participants were analyzed. Salivary samples collected at different time points were analyzed using IA and LC-MS/MS. Serum samples were analyzed for cortisol, cortisol-binding globulin, and free cortisol. The statistical analyses included correlations and method comparisons.

Results

The diurnal salivary cortisol profiles exhibited a comparable circadian rhythm pattern; however, the concentrations measured using IA were consistently higher than those measured using LC-MS/MS. The correlation analysis revealed robust associations among salivary cortisol (IA), salivary cortisol (LC-MS/MS), and serum-free cortisol levels (LC-MS/MS). However, the method comparison revealed a systematic bias between IA and LC-MS/MS in salivary cortisol measurement.

Conclusions

This study contributes to the ongoing debate on assay techniques by affirming the suitability of IA and LC-MS/MS for salivary cortisol measurement to assess dynamic changes in HPA axis activity. The identified systematic bias emphasizes the importance of selecting methods based on specific research or clinical requirements.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Heat inactivation of SARS-CoV 2 enabled the measurement of salivary cortisol during COVID-19 pandemic

BACKGROUND AND AIM

Salivary cortisol has become an essential tool in the management of cortisol-related disease. In 2020 the sudden outbreak of COVID-19 pandemic caused several concerns about the use of saliva, due to the risk of contamination, and a European consensus further discourage using salivary cortisol. To decrease infectious risk, we handled specimens by applying a heat treatment to inactivate viral particles, further evaluating the impact of the COVID-19 pandemic on the use of salivary cortisol in clinical practice.

MATERIAL AND METHODS

Saliva samples were exposed for 10 min at 70 °C, then cortisol was measured using LC-MS/MS. The number of salivary cortisol examinations from 2013 to 2022 was extracted from the local electronic database: those performed in 2019, 2020, and 2021 were analyzed and compared with the historical data.

RESULTS

During 2020 we observed a decrease of 408 (-20%) examinations (p = 0.05) compared to 2019; especially in salivary cortisol daily rhythm and salivary cortisol/cortisone ratio (respectively reduction of 47% and 88%, p = 0.003 and p = 0.001). Analyzing year 2021 compared with 2020 we reported an increase of 420 examinations (+20%, p = 0.01), with a complete recovery of salivary cortisol measurement (considering 2019: p = 0.71). Major differences were observed between morning salivary cortisol (-20%, p = 0.017), LNSC (-21%, p = 0.012) and salivary cortisol rhythm (-22%, p = 0.056). No Sars-Cov2 infections related to working exposure were reported among laboratory's employers.

CONCLUSIONS

We speculate that the adoption of an appropriate technique to inactivate viral particles in saliva specimens allowed the safety maintenance of salivary collections, also during the Sars-CoV-2 outbreak.

Examining surgeon stress in robotic and laparoscopic surgery

Robotic surgery may decrease surgeon stress compared to laparoscopic. To evaluate intraoperative surgeon stress, we measured salivary alpha-amylase and cortisol. We hypothesized robotic elicited lower increases in surgeon salivary amylase and cortisol than laparoscopic. Surgical faculty (n = 7) performing laparoscopic and robotic operations participated. Demographics: age, years in practice, time using laparoscopic vs robotic, comfort level and enthusiasm for each. Operative data included operative time, WRVU (surgical "effort"), resident year. Saliva was collected using passive drool collection system at beginning, middle and end of each case; amylase and cortisol measured using ELISA. Standard values were created using 7-minute exercise (HIIT), collecting saliva pre- and post-workout. Linear regression and Student's t test used for statistical analysis; p values < 0.05 were significant. Ninety-four cases (56 robotic, 38 laparoscopic) were collected (April-October 2022). Standardized change in amylase was 8.4 ± 4.5 (p < 0.001). Among operations, raw maximum amylase change in laparoscopic and robotic was 23.4 ± 11.5 and 22.2 ± 13.4; raw maximum cortisol change was 44.21 ± 46.57 and 53.21 ± 50.36, respectively. Values normalized to individual surgeon HIIT response, WRVU, and operative time, showing 40% decrease in amylase in robotic: 0.095 ± 0.12, vs laparoscopic: 0.164 ± 0.16 (p < 0.02). Normalized change in cortisol was: laparoscopic 0.30 ± 0.44, robotic 0.22 ± 0.4 (p = NS). On linear regression (p < 0.001), surgeons comfortable with complex laparoscopic cases had lower change in normalized amylase (p < 0.01); comfort with complex robotic was not significant. Robotic may be less physiologically stressful, eliciting less increase in salivary amylase than laparoscopic. Comfort with complex laparoscopic decreased stress in robotic, suggesting laparoscopic experience is valuable prior to robotic.

Large litters have a detrimental impact on litter performance and postpartum maternal behaviour in primiparous sows

BACKGROUND

Our previous study confirmed that large litter size adversely affects prepartum maternal hormones and behaviour, concurrently with heightened oxidative stress in primiparous sows. The purpose of this study was to examine the effect of large litter size on litter performance, postpartum maternal behaviour, salivary cortisol levels, and colostral immunoglobulin levels in sows, as well as investigate their correlations with the levels of oxidative stress parameters.

RESULTS

A total of 24 primiparous sows (Landrace[Formula: see text]Large white) and their offspring were categorised into two groups based on litter size: NORMAL (n = 8) with litter size ranging from 7 to 14 (mean 11.5[Formula: see text]2.7), and LARGE (n=16) with litter size ranging from 15 to 20 (mean 15.9[Formula: see text]1.4). All sows were housed in a group housing system during gestation and transitioned to an adaptable loose housing system (2.4[Formula: see text]2.3 m) during the farrowing and lactation periods. The nursing and carefulness behaviour of the sows was monitored over a 24-h period between 72 and 96 h after parturition. Saliva samples were collected for cortisol assay on 35, 21, and 7 days before parturition (D-35, D-21, and D-7, respectively), as well as on days 1, 7, and 28 after parturition (D1, D7, and D28, respectively). On D1, higher piglet mortality rates were observed among the LARGE group compared to the NORMAL group (p<0.01). The total and successful nursing behaviours of the sows were less frequent in the LARGE group than in the NORMAL group (p<0.05, for both), and the carefulness score of the LARGE group was also lower than that of the NORMAL group (p< 0.01). On D1, cortisol levels in LARGE sows were higher than those in NORMAL sows (p< 0.05), and for other time points (D-21, D-7, D7, and D28), cortisol levels in LARGE sows tended to be higher than those in NORMAL sows (p < 0.10, for all). Successful nursing behaviour displayed negative correlations with levels of salivary cortisol and certain oxidative stress parameters measured on D1.

CONCLUSIONS

These findings suggest that the strategy for alleviating physiological and oxidative stress during the peripartum periods could benefit potential postpartum maternal behaviour and litter performance in the sows with large litters.

Effects of menstrual cycle phase and ovulation on the salivary cortisol awakening response

The cortisol awakening response (CAR) is influenced by several state and trait variables, one of which might be the menstrual cycle in women. Previous results suggested that the CAR is enhanced around ovulation, which is why it has been recommended to avoid sampling during the ovulatory phase. In two separate studies, we aimed to replicate previous findings that reported the CAR's modulation across the menstrual cycle, especially during ovulation. In Study 1, a group of 27 healthy naturally cycling women collected saliva at 0, 30, 45, and 60 min post-awakening on two days during their follicular, ovulatory, and luteal phases in a repeated measures design. In Study 2, CAR samples were collected from 30 healthy naturally cycling women on seven consecutive days around the expected ovulation. To increase reliability of CAR measurements, participants' compliance of saliva sampling times was monitored, ovarian steroids (estradiol and progesterone) were collected, and ovulation was confirmed with specific test kits. Contrary to our expectations, we detected no differences in the CAR over the menstrual cycle, and no significant association with variations in estradiol and progesterone. In addition, we excluded confounding effects such as compliance and validated the cycle phase. These results suggest that the CAR is largely robust against hormonal variations across the menstrual cycle, including the mid-cycle phase around ovulation. However, further research is needed to understand the potential ovarian steroid-induced modulation of HPA axis functioning and the menstrual cycle's effects on salivary cortisol levels in psychobiological studies.

The association between depression and the cortisol awakening response is moderated by loneliness in men from a non-clinical sample

Previous studies investigating cortisol levels in people with depression or depressive symptoms have provided mixed findings. It has been suggested that the difficulty to generalize findings across studies in this field might be related to interindividual variability in experiencing depressive symptoms in terms of clinical and social contexts. Therefore, in the present study we aimed to test the association of morning cortisol levels and depressive symptoms in a non-clinical sample of young men taking into consideration the level of perceived loneliness. We hypothesized that the level of loneliness might moderate the association between morning cortisol levels and depressive symptoms. A total of 102 participants (aged 29.9 ± 5.0 years) completed questionnaires measuring the levels of depressive and anxiety symptoms, perceived stress, and loneliness. Cortisol levels were determined in four morning samples of saliva. There were significant positive correlations of the cortisol awakening response (CAR) and the mean increase in cortisol levels during the measurement period (MnInc) with the levels of depressive symptoms and loneliness. Moreover, a significant association of the depressive symptoms by loneliness interaction with the CAR and the MnInc was found. Specifically, the correlation of depressive symptoms with the CAR and the MnInc appeared to be significant and negative at high levels of loneliness. No significant association between depressive symptoms and the CAR was observed in men with low levels of loneliness. There were no significant associations of depressive symptoms, loneliness and the depressive symptoms by loneliness interaction with cortisol levels at awakening. In conclusion, findings from the present study indicate the importance of social contexts in understanding the association between altered activity of the hypothalamic-pituitary-adrenal axis and depressive symptoms in men.

Experiences with transvaginal Ovum Pick-Up (OPU) in sows

Transvaginal ultrasound-guided Ovum Pick-Up (OPU) is an established technique in other species. Due to several challenges, there are few publications addressing the procedure in sows. An efficient OPU technique may allow for the collection of numerous oocytes from valuable sows for porcine in vitro embryo production, gene editing and cloning programmes, or cryopreservation. We aimed to improve transvaginal OPU and equipment for this technique in sows. In experiment 1, we conducted 13 OPU sessions on three Landrace x Large White hybrid sows under general anaesthesia, while the second experiment explored OPU in non-sedated animals (N = 6) physically restrained in a commercial claw trimming chute. The experiments resulted in 6.6 ± 5.6 (mean ± SD) and 7.7 ± 8.9 recovered cumulus-oocyte complexes per session, respectively. Post-mortem examination of the pelvic and abdominal cavities of the three sows subjected to repeated OPU sessions did not reveal major acute or chronic pathological lesions. The only sow which was inseminated after the experiment delivered 16 liveborn piglets at term. Salivary cortisol levels increased during the procedure in non-sedated and physically restrained sows but returned to baseline 1 h later (n = 5), indicating a short-term stress response. The described OPU technique and equipment have the potential to retrieve considerable numbers of oocytes by repeated procedures on valuable mature sows. Follow-up studies are needed to optimize the efficiency of the aspiration of high-quality oocytes and to describe the developmental competence of these OPU-derived oocytes. It is also essential to further investigate sow welfare during and after the procedure before recommending porcine transvaginal OPU as a sustainable and welfare-friendly procedure.

Effects of slow breathing training on hemodynamic changes, cardiac autonomic function and neuroendocrine response in people with high blood pressure: A randomized control trial

BACKGROUND

High blood pressure (BP) is a non-communicable disease that is a risk factor for cardiovascular disease and is the leading cause of mortality and morbidity worldwide. High BP can be managed by both pharmacological and non-pharmacological interventions. Non-pharmacological treatment, such as slow-breathing training (SBT), has been shown to reduce BP. However, there are few studies on the effect of SBT on both cardiac activation and oxidative stress in people with high BP.

OBJECTIVES

To explore the effect of SBT on cardiac autonomic function (i.e., heart rate variability: HRV) and neuroendocrine response (i.e., salivary cortisol).

METHODS

One hundred people (including 89 women) with high BP were randomly assigned to either a control (n = 50) or intervention group (n = 50). The intervention program was conducted for 30 min per day, for 5 days per week, for 4 weeks, with a total of 20 sessions of the SBT at the rate of 10 times per minute, whereas the control group was required to continue with their daily routine. HRV, BP, and salivary cortisol were measured before and after the intervention program. A two-way mixed ANOVA was performed for within-group and between-group comparisons over time.

RESULTS

Of the 100 participants, 71 individuals completed the study. The participants in the intervention group had a lower BP and salivary cortisol levels compared to those in the control group (p < .05). Further, those participants showed an increase in the standard deviation of normal R-R intervals after the 4-week intervention program (p < .05).

CONCLUSION

This study provided evidence demonstrating the effect of SBT on cardiac autonomic and stress reactivity, which has important implications for health promotion in people with high BP.

CLINICAL TRIAL REGISTRATION NUMBER

TCTR20180302008.

The effectiveness of rational emotive behavior therapy (REBT) and mindfulness-based intervention (MBI) on psychological, physiological and executive functions as a proxy for sports performance

BACKGROUND

In the current study, we conducted a comparative analysis involving three distinct groups: one receiving group-based rational emotive behavior therapy (REBT), another undergoing a mindfulness-based intervention (MBI), and a third group serving as the control. The aim of the study was to explore the effectiveness of the two interventions on specific psychological (competitive anxiety, perfectionism, irrational beliefs), physiological (salivary cortisol levels), and neurocognitive (executive functions: working memory, inhibition, cognitive flexibility) functions in Hungarian junior ice hockey players.

METHODS

The participants consisted of 10 females and 36 males (NREBT=12, NMINDFULNESS=14, NCONTROL=20). We used questionnaires to assess competitive anxiety, perfectionism, and irrational beliefs. The components of executive functions were measured using a computerized testing system, while cortisol levels were examined through salivary samples. Prior to and after the interventions, each participant underwent all measurements, after which we conducted repeated measures ANOVA on our data.

RESULTS

We found REBT to be an effective intervention for the regulation of competitive anxiety, perfectionism, and irrational beliefs as well as for improving some components of executive functions (inhibition and cognitive flexibility). Mindfulness was found to improve athletes' processing speed and set-shifting abilities, which are related to cognitive flexibility and metacognitive processes.

CONCLUSION

In conclusion, we explore implications of these findings regarding how each approach is posited to enhance sports performance, using neurocognitive functions as a proxy. These findings are useful for further research and practical implications.

Reduced neural responses to pleasant odor stimuli after acute psychological stress is associated with cortisol reactivity

Acute stress alters olfactory perception. However, little is known about the neural processing of olfactory stimuli after acute stress exposure and the role of cortisol in such an effect. Here, we used an event-related olfactory fMRI paradigm to investigate brain responses to odors of different valence (unpleasant, pleasant, or neutral) in healthy young adults following an acute stress (Trier Social Stress Test, TSST) induction (N = 22) or a non-stressful resting condition (N = 22). We obtained the odor pleasantness, intensity, and familiarity ratings after the acute stress induction or resting condition. We also measured the participants' perceived stress and salivary cortisol at four time points during the procedure. We found a stress-related decrease in brain activation in response to the pleasant, but not to the neutral or unpleasant odor stimuli in the right piriform cortex extending to the right amygdala, the right orbitofrontal cortex, and the right insula. In addition, activation of clusters within the regions of interest were negatively associated with individual baseline-to-peak increase in salivary cortisol levels after stress. We also found increased functional connectivity between the right piriform cortex and the right insula after stress when the pleasant odor was presented. The strength of the connectivity was positively correlated with increased perceived stress levels immediately after stress exposure. These results provide novel evidence for the effects of acute stress in attenuating the neural processing of a pleasant olfactory stimulus. Together with previous findings, the effect of acute stress on human olfactory perception appears to depend on both the valence and the concentration (e.g., peri-threshold or suprathreshold levels) of odor stimuli.

Pharmacological Treatment of Cushing's Syndrome

The 1st line treatment of Cushing's syndrome is surgery, whatever the aetiology. The role of pharmacological treatment is clear in cases where surgery fails or is impossible, in cases of metastases, or while awaiting the delayed effects of radiotherapy. However, certain situations remain controversial, in particular the possible role of pharmacological treatment as a preparation for surgery. This situation must be divided into 2 parts, severe hypercortisolism with immediate vital risk and non-severe hypercortisolism with diagnostic delay. The initiation and adjustment of treatment doses is also controversial, with the possibility of titration by gradual dose increase based on biological markers, or a more radical "block and replace" approach in which the ultimate goal is to achieve hypocortisolism, which can then be supplemented. Each of these approaches has its advantages and drawbacks and should probably be reserved for different patient profiles depending on the severity of hypercortisolism. In this review, we will focus specifically on these 2 points, namely the potential role of preoperative pharmacological treatment and, more generally, the optimal way to initiate and monitor drug treatment to ensure that eucortisolism or hypocortisolism is achieved. We will define for each part which profiles of patients should be the most adapted to try to give advice on the optimal management of patients with hypercortisolism.

Hypothalamic-pituitary-adrenal axis responsivity during adolescence in relation to psychopathic personality traits later in life

Psychopathic personality traits have been linked to low physiological arousal, particularly among high risk and forensic samples. A core indicator of physiological arousal is the activity of the hypothalamic-pituitary-adrenal (HPA) axis; however, findings of a link between HPA axis functioning and psychopathic personality traits have been inconsistent. Furthermore, given sex differences in both HPA axis responsivity and psychopathic personality traits, the association may be expected to differ between men and women. The aim of this study was to investigate the association between HPA axis responsivity in mid-adolescence and psychopathic personality traits in early adulthood and determine whether the association was moderated by sex. We examined this link in a general population sample of twins (N = 556). Adolescents participated in a psychosocial stress task during which samples of salivary cortisol were collected (11-15 years) and reported psychopathic personality traits using the Triarchic Psychopathy Measure (19-20 years). Multilevel linear regression models were estimated in which psychopathic personality traits (boldness, meanness and disinhibition), and their interactions with sex, were regressed on HPA axis responsivity. The study was pre-registered on the Open Science Framework (osf.io/gs2a8). Preliminary analyses showed that cortisol levels did not increase significantly during the stressor task but decreased during recovery. Results showed that there was no association between HPA axis responsivity in mid-adolescence and psychopathic personality traits in early adulthood. The associations were not moderated by sex. Findings suggest that HPA axis responsivity in mid-adolescence did not serve as a biological marker for psychopathic personality traits among young adults from the general population.

Revisiting the cortisol reference ranges in humans: the role of demographics

The current study explores the effect of demographics on serum cortisol expression in a study group of 52 individuals to improve the current serum reference ranges to produce personalized expression profiles consequently increasing clinical confidence in the diagnosis. The serum cortisol concentration was inspected against demographical data like age, sex, and body mass index and showed an association with age and sex. The serum cortisol values also indicated a positive association with chronic illnesses however this finding requires a more focused study for establishment. Additionally, saliva samples are also collected from the same study group at the same time through drool and an absorbent sponge and correlated with serum values to draw an alternative route of serological testing. Salivary cortisol from drool showed a linear correlation with Pearson's correlation coefficients of 0.71 and 0.72 with serum cortisol and with saliva samples collected using a porous sponge respectively. Overall, the study shows the role of demographics in shaping the reference ranges for cortisol, suggesting a path for developing personalized diagnostics. The study also highlights the efficacy of saliva as an alternative to serum cortisol to facilitate cortisol measurement for efficient stress management.

Comparison of salivary cortisol levels between women with functional hypothalamic amenorrhea and healthy women: a pilot study

INTRODUCTION

Functional Hypothalamic Amenorrhea (FHA) has been associated with excessive-chronic stress, eating disorders, and weight loss. A common feature is the increased serum cortisol, but its measurement has many limitations. Currently, salivary cortisol (SC) has been proposed as a more sensitive and adequate index.

AIM

To investigate the SC alterations through a 24-h period and the possible correlation with the severity of stress in women with FHA.

METHODS

Between July 2019 and March 2021, 12 FHA women and 12 healthy controls of comparable age were included. Psychological, eating, and physical abnormalities were evaluated by applying equivalent validated self-questionnaires.

RESULTS

No significant differences were found between FHA women and healthy individuals with respect to morning (8:00 am) serum cortisol and ACTH (522.5 ± 162.2 vs 442 ± 138.5 nmol/l; p = 0.204 and 37 ± 44.8 vs 17.4 ± 10.8 pg/ml; p = 0.186, respectively). Women with FHA had statistically significant higher morning SC compared to control subjects (21.8 ± 5.9 nmol/l vs 12.8 ± 3.8 nmol/l; p < 0.001), while no significant differences were found regarding the afternoon (4:00 pm) and midnight (12:00 am) SC. A significant positive correlation was found between morning SC and morning serum cortisol (rho = 0.532; p = 0.007), EAT-26 (rho = 0.527; p = 0.008) and HADS-Anxiety score (rho = 0.471; p = 0.02). Additionally, a significant negative correlation between morning SC and BMI was observed (rho = -0.53; p = 0.009).

CONCLUSION

Compared to serum cortisol, SC seems to express better the hypercortisolemic state of women with FHA and correlates well with the underlying contributing factors. Larger studies are needed in order to confirm these results and validate the optimal SC cut-off value associated with the development of FHA.

Longitudinal association between saliva and hair cortisol concentration: A systematic comparison

Cortisol assays from hair have become increasingly common in psychoneuroendocrinological research as indicators of long-term output relevant to stress and health outcomes. Comparisons of hair cortisol concentration (HCC) with salivary samples have produced mixed findings, and it remains unclear which aspects of the diurnal salivary profile correspond most closely to HCC, and what time intervals between saliva and hair sampling are most relevant, taking the rate of hair growth into account. This longitudinal study aimed to evaluate the correspondence between HCC and parameters of total salivary cortisol output in the morning (CARauc and CARi) and during the rest of the day excluding the early morning period (DAYauc), by systematically studying three time periods - two weeks, four weeks, and six weeks - before hair sampling. At each time period, 54 female university students (mean age: 20.85 ± 1.16 years) provided three saliva cortisol samples on day 1 at 11 am, 3 pm, at bedtime, then two samples the following day on waking and 30 min after awakening. Hair strand collection (1 cm nearest the scalp) took place two weeks after the last saliva sample. Results of multivariable regressions indicate that HCC was consistently associated with DAYauc for all three time periods and with the aggregate DAYauc across days after adjusting for age, body mass index, smoking, oral contraceptive use, hair washing frequency and hair treatments. The strongest associations were found for DAYauc two weeks before hair sampling (β = 0.578, p < 0.001) and the aggregated DAYauc across all three time periods (β = 0.596, p < 0.001), although the confidence intervals overlapped those for four and six week analyses. There was no significant association between HCC and either CARauc or CARi. Our study confirms that hair cortisol could be a reliable retrospective biomarker of basal and long-term cortisol output secretion at least up to six weeks earlier. The results contribute to a better understanding of the different associations between HCC and salivary cortisol in the morning and the rest of the day, while also having implications for the use of HCC as an outcome measure in intervention and treatment research.

The effect of virtual reality distraction on anxiety level during dental treatment among anxious pediatric patients: a randomized clinical trial

This study evaluated the effect of Virtual Reality Distraction (VRD) on dental anxiety among anxious children undergoing prophylactic dental treatment by utilizing both subjective (Venham Anxiety and Behavioral Rating Scale (VABRS)) and objective (heart rate (HR) and salivary cortisol level (SCL)) measures. This randomized controlled study included 36 (6- to 14-year-old) healthy and anxious children who needed prophylactic dental treatment and had a history of previous dental treatment. The eligible children's anxiety level was evaluated using a modified version of the Abeer Dental Anxiety Scale-Arabic version (M-ACDAS) and those who scored at least 14 or more out of 21 were included. Participants were randomly distributed to either the VRD or control group. In the VRD group, participants wore the VRD eyeglasses during prophylactic dental treatment. In the control group, subjects received their treatment while watching a video cartoon on a regular screen. The participants were videotaped during the treatment, and their HR was recorded at four time points. Also, a sample from each participant's saliva was collected twice, at the baseline and after the procedure. The mean M-ACDAS score at baseline in the VRD and the control groups was not statistically significant (p = 0.424). At the end of the treatment, the SCL was significantly lower in the VRD group (p < 0.001). Neither the VABRS (p = 0.171) nor the HR significantly differed between the VRD and control groups. Virtual reality distraction is a non-invasive method that has the potential to significantly reduce anxiety during prophylactic dental treatment among anxious children.

Does workplace telepressure get under the skin? Protocol for an ambulatory assessment study on wellbeing and health-related physiological, experiential, and behavioral concomitants of workplace telepressure

BACKGROUND

The daily working life of many employees requires the use of modern information and communication technology (ICT) devices such as computers, tablets, and smartphones. The double-edged nature of digital work environments has been increasingly highlighted. Benefits such as increased flexibility come at a personal cost. One of the potential downsides is workplace telepressure, i.e., the experience of urge and preoccupation to quickly reply to work-related messages and demands using ICT. There is initial - mainly survey-based-evidence that workplace telepressure may have negative effects on a variety of wellbeing and health outcomes.

AIMS AND HYPOTHESES

Adopting the Effort-Recovery Model and the concept of allostatic load as theoretical frameworks, the present study aims to investigate the hypothesis that workplace telepressure is significantly associated with increased "wear and tear", in the form of more psychosomatic complaints, worse sleep quality (self-reported and actigraphy-based), worse mood, and biological alterations (lower cardiac vagal tone, lower anabolic balance defined as the ratio of salivary dehydroepiandrosterone to salivary cortisol, and higher salivary alpha-amylase). Additionally, the study aims to investigate the hypothesis that connection to work defined as work-related workload and work-related perseverative cognition plays a significant role in the mediation of these relationships.

METHODS

To test our hypotheses, we will conduct an ambulatory assessment study with a convenience sample of 120 healthy workers regularly using ICTs for job communication. For one week, participants will be asked to complete electronic diaries assessing their level of workplace telepressure, psychosomatic complaints, sleep quality, mood, work-related workload, and work-related perseverative cognition. They will also continuously wear the Bittium Faros 180L ECG monitor, the wrist-worn actigraph MotionWatch 8, and perform saliva sampling five times per day.

DISCUSSION

This study will be the most comprehensive ambulatory investigation of workplace telepressure and its psychophysiological concomitants to date and constitutes an important step towards understanding how high levels of workplace telepressure may lead in the long term to secondary alterations (e.g., hypertension, chronic inflammation) and disease (e.g., heart disease). The findings of this study are also anticipated to contribute to guiding the development and implementation of interventions, programs, and policies relevant to employees' digital wellbeing.

Diagnostic Accuracy of Morning Salivary Cortisol in the Assessment of the Hypothalamic-Pituitary-Adrenal Axis Recovery after Prolonged Corticosteroid Therapy in Children

INTRODUCTION

Assessment of the hypothalamic-pituitary-adrenal (HPA) axis is necessary after prolonged glucocorticoid therapy withdrawal. Salivary cortisol reflects 65% of the free circulating cortisol fraction. Saliva collection is non-invasive and child friendly.

OBJECTIVE

We aimed to evaluate the diagnostic accuracy of morning salivary cortisol (mSAF) to determine HPA recovery after prolonged corticosteroid therapy in children.

METHODS

We conducted a prospective, validation study in 171 paediatric patients (mean ± SD age: 13.0 ± 4.4 years) who received glucocorticoids for >4 weeks (median and interquartile range: 11 [7-14] months) and were referred for therapy withdrawal. Serum and saliva samples were collected between 8 and 9 a.m. on the same day. Cortisol was measured by an electrochemiluminescence immunoassay (ECLIA) 48 h after cessation of glucocorticoid therapy. Serum cortisol ≥193 nmol/L was used as the reference cut-off value for HPA recovery after glucocorticoid withdrawal and mSAF as the index test.

RESULTS

The cut-off concentration obtained by ROC for mSAF was ≥5.0 nmol/L. True positive and true negative results were observed in 85/171 and 40/171 children, respectively. The false-positive rate was low (3/171, 1.7%); however, false-negative results were observed in 43/171 (25%) children. The main ROC results (95% CI) were area under curve: 0.98 (0.96-0.99), sensitivity: 0.66 (0.57-0.75), specificity: 0.93 (0.81-0.99), positive predictive value: 0.97 (0.90-0.99), negative predictive value: 0.48 (0.37-0.59), LR+: 9.5, and diagnostic accuracy: 73.1%.

CONCLUSION

The present study supports that mSAF ≥5.0 nmol/L by ECLIA is a non-invasive biomarker for the assessment of HPA recovery after prolonged glucocorticoid therapy in paediatric patients, with a positive predictive value of 97%. This proposed cut-off should be further validated using gold standard techniques for steroid quantification such as liquid chromatography-tandem mass spectrometry.

Increased sensitivity to unpleasant odor following acute psychological stress

Previous studies have reported increased sensitivity to malodor after acute stress in humans. However, it is unclear whether stress-related "hypersensitivity" to odors depends on odor pleasantness. Forty participants (mean age 19.13 ± 1.14 years, 21 men and 19 women) completed a stress (Trier Social Stress Test, TSST) and a control session in randomized order. Detection threshold to three odors varying in pleasantness (pleasant: β-Citronellol; neutral: 2-Heptanol; unpleasant: 4-Methylpentanoic acid), odor discrimination, odor identification, sensitivity to trigeminal odor, and suprathreshold odor perception were assessed after participants' completion of the stress or the control tasks. Salivary cortisol, subjective stress, and heart rate were assessed throughout the experiment. After TSST, participants showed an increased sensitivity for the unpleasant odor. Moreover, there were correlations between stress-related salivary cortisol and the increased sensitivity for the unpleasant odor (r = 0.32, p = 0.05) and the neutral odor (r = 0.34, p < 0.05). Besides, salivary cortisol response was correlated to the increased odor discrimination performance (Δ stress - control) (r = 0.34, p < 0.05). The post-TSST perceived stress was correlated with decreased odor identification and decreased sensitivity to the unpleasant odor. After stress, participants rated lower pleasantness for β-Citronellol than the control condition. Overall, these results suggest the impact of acute psychological stress on odor sensitivity depends on the odor valence, and that the stress-related cortisol responses may play an important role in this effect.

Do diurnal salivary cortisol curves carry meaningful information about the regulatory biology of the HPA axis in healthy humans?

Salivary cortisol stress biomarkers have been extensively used in epidemiological work to document links between stress and ill health. There has been little effort to ground field friendly cortisol measures in the hypothalamic-pituitary-adrenal (HPA) axis regulatory biology that is likely relevant to delineating mechanistic pathways leading from stress exposure to detrimental health outcomes. Here, we utilized a healthy convenience sample (n = 140) to examine normal linkages between extensively collected salivary cortisol measures and available laboratory probes of HPA axis regulatory biology. Participants provided 9 saliva samples per day over 6 days within a month, while engaging in usual activities, and also participated in 5 regulatory tests (adrenocorticoptripin stimulation, dexamethasone/corticotropin-releasing-hormone stimulation, metyrapone, dexamethasone suppression, and Trier Social Stress Test). Logistical regression was used to test specific predictions linking cortisol curve components to regulatory variables and to explore widely for non-predicted associations. We found support for 2 of 3 original hypotheses, showing associations (1) between cortisol diurnal decline and feedback sensitivity as measured by dexamethasone suppression, and (2) between morning cortisol levels and adrenal sensitivity. We did not find links between central drive (metyrapone test) and end of day salivary levels. We confirmed an a priori expectation of limited linkage between regulatory biology and diurnal salivary cortisol measures, beyond those predicted. These data support an emerging focus on measures related to diurnal decline in epidemiological stress work. They raise questions about the biological meaning of other curve components, including morning cortisol levels, and perhaps CAR (Cortisol Awakening Response). If morning cortisol dynamics are linked to stress, more work on adrenal sensitivity in stress adaptation and stress-health links may be warranted.

Investigation of the effect of music listened to by patients with moderate dental anxiety during restoration of posterior occlusal dental caries

OBJECTIVE

The aim of this randomized controlled study was to investigate the effect of music therapy during restorative dental treatments on patients with moderate dental anxiety.

MATERIALS AND METHODS

Seventy patients were determined to have moderate dental anxiety by the Modified Dental Anxiety Scale (MDAS) and were divided randomly into two groups (n = 35). The first group did not listen to music during their restorative treatment (control group), and the second group listened to music of their choice (experimental group). Systolic blood pressure, diastolic blood pressure, heart rate, oxygen saturation, and body temperature were measured three times for each patient: once before the treatment, once after their dental caries were removed, and once at the end of the treatment. Salivary cortisol samples were taken from each patient before and after the treatment. The MDAS was re-administered to the patients at the end of the treatment, and the data were analyzed statistically.

RESULTS

Only the diastolic blood pressure (P = 0.042) and the MDAS scores of the experimental group (P = 0.001) were significantly lower than the control group at the end of the treatment.

CONCLUSION

While music listening did not have an effect on the physiologic parameters of the patients during restorative treatment, it decreased the MDAS scores of the patients.

CLINICAL RELEVANCE

Although music therapy did not affect the physiological parameters during the restorative dental treatment, it may help to reduce patients' self reported anxiety level.

The Effect of Anxiety and Stress on Acceptance of Dental Procedure before and after Inhalation Sedation in Pediatric Patients: An In Vivo Study

Aim

The study aimed to assess the anxiety and stress levels on acceptance of dental treatment in child patients approaching dental extraction procedures before and after nitrous oxide (N₂O) inhalation sedation (IHS) by measuring serum amyloid A (SAA) and salivary cortisol (SC).

Materials and methods

A total of 32 children, ages ranging from 6 to 10 years, were randomly grouped as TI (before N₂O IHS) and TII (after N₂O IHS). Saliva samples were taken for biochemical evaluation of SAA before and after the procedure. Subjectively anxiety and stress levels were evaluated using modified child dental anxiety scale (MCDAS). Wilcoxon rank-sum test was used to compare the means of dental anxiety, SAA, and SC before and after N₂O IHS. The Karl Pearson correlation coefficient was employed to determine the correlation between dental anxiety and SAA and SC before and after N₂O IHS.

Results

There were significant differences in the dental anxiety level in child patients after administration of N₂O IHS, and it also showed an increased rate of acceptance of dental treatment.

Conclusion

This study showed that N₂O is a safe and effective method in reducing dental anxiety and increasing acceptance of dental treatment in child patients with improved behavior and with no adverse effects.

Clinical significance

Anxiety and stress will always hinder the acceptance of dental treatment in child patients, especially during extraction procedures. N₂O IHS is a safe and effective technique to overcome anxiety and stress in child patients and as well as allows them to undergo dental treatment with improved behavior.

How to cite this article

Kunta S, Arora RV, Jain R, et al. The Effect of Anxiety and Stress on Acceptance of Dental Procedure before and after Inhalation Sedation in Pediatric Patients: An In Vivo Study. Int J Clin Pediatr Dent 2023;16(2):302-307.

Separating the influences of means and daily variations of sleep on the stress-induced salivary cortisol response

BACKGROUND

Previous research regarding the effects of sleep quality and quantity on the acute stress response has yielded inconsistent findings. This may be attributed to various factors, including composite sleep components (i.e., means and daily variations) and mixed cortisol stress response (i.e., reactivity and recovery). Thus, this study aimed to separate the effects of means and daily variations of sleep on the reactivity and recovery of cortisol responses to psychological challenges.

METHODS

In study 1, we recruited 41 healthy participants (24 women; age range, 18-23 years), monitored their sleep during seven consecutive days via wrist actigraphy and sleep diaries, and adopted the Trier Social Stress Test (TSST) paradigm to induce acute stress. Study 2 consisted of a validation experiment using the ScanSTRESS paradigm, which included 77 additional healthy individuals (35 women; age range, 18-26 years). Similarly to the TSST, the ScanSTRESS induces acute stress using uncontrollability and social evaluation. In both studies, saliva samples from the participants were collected before, during, and after the acute stress task.

RESULTS

Using residual dynamic structural equation modeling, both study 1 and study 2 demonstrated that higher means of objective sleep efficiency, and longer means of objective sleep duration were related to greater cortisol recovery. In addition, fewer daily variations in objective sleep duration were associated with greater cortisol recovery. However, there was no correlation between sleep variables and cortisol reactivity, except for the daily variations in objective sleep duration in study 2. No correlation was observed between subjective sleep and cortisol response to stress.

CONCLUSIONS

The present study separated two features of multi-day sleep patterns and two components of cortisol stress response, providing a more comprehensive picture of the effect of sleep on the stress-induced salivary cortisol response, and contributing to the future development of targeted interventions for stress-related disorders.

Changes in psychological and cognitive variables as well as cortisol levels in recovered Covid-19 patients: a longitudinal study

BACKGROUND

Decreased psychological and cognitive functioning is one of the complications of Covid-19 disease. We aimed to evaluate mental health, cognitive functioning, and salivary cortisol levels in Covid-19 patients with different disease severities in three 45-day intervals after recovery.

METHODS

258 Covid-19 patients were assigned into three groups based on their disease severity: 112 patients in mild group, 67 patients in moderate group and 79 patients in severe group. The participants underwent psychological evaluations (including Depression, Anxiety and Stress Scale questionnaire, Beck Depression Inventory, SpeilBerger State-Trait Anxiety Inventory, Pittsburgh Sleep Quality Inventory), cognitive assessments (The Paced Auditory Serial Addition Test) and salivary cortisol level evaluation in three 45-day periods. Non-parametric statistical methods were applied for psychological and cognitive indicators, while two-way mixed model ANOVA was used to evaluate the cortisol concentration in three replications.

RESULTS

The group of mild patients became more anxious and the group of moderate patients became more anxious and depressed. But all three groups of patients developed severe sleep disorders over time. For cognitive functioning, although the results showed a decrease in the correct response rate, a significant increase in the correct response rate was observed in all three groups in all three measurements. However, the response speed not only did not increase, but also decreased in severe group. Cortisol level had a markedly increasing trend in all three groups.

CONCLUSION

Improvement of cognitive functioning was in line with the increase in cortisol. Besides, the decrease in mental health had no effect on the cognitive functioning.

Effect of wither application of an analogue of pig appeasing pheromone on encounters between unfamiliar mini-pigs

BACKGROUND

The practice of mixing unfamiliar pigs on farms is common but results in fighting, welfare problems and performance issues. Pigs have different ways of resolving social conflicts, including aggressive and affiliative behaviours. Synthetic appeasing pheromones have demonstrated many positive effects in animal husbandry and are regularly used by breeders to improve animal welfare and performance. The aim of the study was to investigate the effect of a new method of applying pig appeasing-pheromone (PAP) to the withers in an experimental model of pig mixing to determine whether PAP reduced aggression and fighting, increased prosocial behaviours, and improved behavioural and physiological indicators of welfare.

RESULTS

PAP reduced fighting between mini-pigs (df = 1; F = 13.47; P = 0.001; mixed logistic regression). Even if not significant, agonistic behaviours tended to be reduced when the treatment was applied (df = 1; F = 4.14; P = 0.058; mixed logistic regression). Likewise, mini-pigs seemed to be scored as not aggressive at all (df = 1; F = 3.61; P = 0.070; GLMM) and to be less aggressive toward the other pig than when placebo was applied. Concerning the latency of the first contact without aggression, a significant effect was found between the PAP and placebo groups (df = 1; χ² = 4.74; P = 0.0295; Cox model). Moreover, even if not significant, the treated mini-pigs seemed to spent more time looking at each other (df = 1; F = 3.59; P = 0.071; GLMM) and immobile and/or ground sniffing (df = 1; F = 3.18; P = 0.088; GLMM) than those that received placebo. No significant difference was found between groups for salivary cortisol concentration (df = 1; F = 0.10; P = 0.752; GLMM), but variances between groups were heterogeneous at every time. No significant difference was found between groups regarding alpha-amylase activity (df = 1; F = 0.25; P = 0.621; GLMM), but variances between groups were heterogeneous at T0, T1 and T3. These results indicate that the variability (dispersion) within each group was lower when PAP was applied than when the placebo was applied.

CONCLUSIONS

The new method of applying PAP improved welfare of mini-pigs (as models of domestic pigs) by reducing fighting, among other interesting results. PAP seems thus a promising biomimetic tool to enhance animal welfare in pig production systems.

Individual differences in latent trait cortisol (LTC): Implications for the onset and course of future depressive symptoms

Research suggests that various indicators of hypothalamic pituitary adrenal (HPA) axis activity prospectively predict depression, but few studies have evaluated whether trait indicators of HPA axis activity are related to depression. Further, no prior study has examined links between trait cortisol and psychopathology using a trait indicator that captures HPA axis activity over multiple time points. Here we examined whether we could construct an across-wave latent trait cortisol (LTC) factor using cortisol samples collected over 13 weeks, and whether the across-wave LTC prospectively predicted new depressive symptom onsets and symptom duration. Emerging adults (n = 85; M age = 19.37 years) provided salivary cortisol samples four times a day (waking, 30 min and 45 min post-waking and bedtime) over three 3-day measurement waves separated by 6 weeks. Diagnostic interviews at 3 timepoints (baseline, 1- and 2.5 years post-baseline) assessed lifetime and current depressive symptoms. Results indicated that the across-wave LTC predicted new onsets of depressive symptoms and longer symptom duration. Follow-up tests revealed that the link between the across-wave LTC and new onsets was not significant after adjusting for past depressive symptoms. These findings suggest that an indicator of individual differences in HPA axis regulation has implications for depressive symptom onsets and course.

Determination of salivary cortisol and salivary pH level in gaming teenagers - A cross-sectional study

Introduction

Internet gaming disorder and cybervictimization has a disproportionate increase during the COVID 19 pandemic. Teenagers and adolescents have high risk for addiction to online gaming. Online gaming increases the stress level of the users affecting the general and the oral health. The study aims to determine the salivary cortisol and salivary pH among the gaming teenagers.

Materials and methods

The cross-sectional study recruited 45 gaming teenagers with the mean age of 15.5 years. The participants were stratified according to the type of online gaming played as mind, aggressive and betting gaming. Their salivary pH and salivary cortisol were assessed. The collected data was analyzed using SPSS version 23.

Results

The mean salivary pH was found to be less among females playing aggressive games (7.11 ± 0.30) and males playing mind games (7.24 ± 0.16). Salivary cortisol level was found to be statistically high in males (6.66 ± 1.33) and females (7.82 ± 0.66) playing aggressive games. The sub-group analysis of salivary pH and cortisol for gender showed a significant difference in the mean salivary cortisol level (p < 0.05) with no difference in the salivary pH (p > 0.05). Based on the number of hours spent in online gaming, there was a significant increase in the mean salivary cortisol level among the participants playing >3 h (p < 0.05).

Conclusion

Salivary cortisol is high among individuals playing aggressive games compared to mind and betting games. Also, salivary cortisol is high in females compared to males with no change in salivary pH.

The effects of momentary loneliness and COVID-19 stressors on hypothalamic-pituitary adrenal (HPA) axis functioning: A lockdown stage changes the association between loneliness and salivary cortisol

The COVID-19 pandemic can be characterized as a chronic stressor affecting the hypothalamic-pituitary-adrenal (HPA) axis, indexed by glucocorticoids (e.g., cortisol). We investigated whether salivary cortisol level is increased during a lockdown and whether a lockdown condition affects the association between loneliness, specific COVID-19 related stressors and salivary cortisol level. We conducted a smartphone-based ecological momentary assessment (EMA) study with 280 participants in Germany who experienced at least mild loneliness and distress amid COVID-19 from August 2020 to March 2021. We measured their momentary loneliness and COVID-related stressors including worries, information seeking behaviors and feelings of restriction during "no-lockdown" or "lockdown" stages amid COVID-19. Their salivary cortisol was measured 4 times on the last day of a 7-day EMA study. We found a significant increase in salivary cortisol levels during lockdown compared to no-lockdown. Lockdown stage was found to moderate the relationship between momentary loneliness and salivary cortisol level, i.e., loneliness was positively related to cortisol level specifically during lockdown. Mechanisms explaining the effect of forced social isolation on the association between loneliness and salivary cortisol need to be investigated in future studies.

Post-awakening salivary alpha-amylase as modulator of treatment response in patients with burnout and major depression

Around 50% of patients with major depression do not respond to standard first-line treatments, such as psychotherapy and pharmacotherapy. At the same time, a subgroup exhibits altered functioning of stress-responsive bodily systems, such as the central locus coeruleus/sympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis. Given that these systems impact arousal and cognition, it is possible that this subgroup contributes to the high rates of non-responders. Our aim was to investigate whether sympathetic and HPA axis activity modulate treatment outcomes in patients with stress-related major depression. A total of N = 74 inpatients (median age: 50, 62% male) with signs of burnout who fulfilled diagnostic criteria for major depression were recruited. Saliva samples were collected at awakening as well as 30 and 45 min later. Alpha-amylase activity and cortisol concentrations were determined before patients underwent evidence-based multimodal treatment. Non-responders were defined as patients exhibiting a &lt;50% decrease in depression on the Beck Depression Inventory. Non-responders had significantly higher post-awakening alpha-amylase activity than responders (p = .025). In addition, alpha-amylase activity increased significantly over the course of treatment (p = .004), irrespective of responder status. Post-awakening cortisol was neither a predictor nor an indicator of treatment response. If future research confirms alpha-amylase activity as a modulator of treatment response, this may indicate a subgroup of patients with major depression which may benefit from augmentative treatments, such as heart rate variability biofeedback and/or cognitive interventions targeting high arousal.

Sensitive and Robust LC-MS/MS Analysis of Salivary Cortisol in Negative Mode

Cortisol is one of the most important glucocorticoids involved in the regulation of human metabolism and physiological stress. Monitoring of levels of cortisol is of immense clinical benefit. In particular, salivary cortisol levels have been shown to correlate well with diurnal changes in cortisol levels in serum and have been used widely for monitoring of cortisol levels for diagnosis and prognosis purposes. We present a sensitive, fast, and robust quantitative liquid chromatography and tandem mass spectrometry (LC-MS/MS) assay for salivary cortisol in negative mode. This assay employs protein precipitation followed by reversed-phase liquid chromatographic separation, negative-mode electrospray ionization (ESI), and MS/MS detection. This assay has a total run time of 5.8 minutes and a limit of quantification of 0.5 ng/mL with a linear range up to 100 ng/mL. No carryover was observed at 10 μg/mL. This assay also incorporates the routine monitoring of prednisolone, a potential interferent to salivary cortisol.

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

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

Stress-induced HPA activation in virtual navigation and spatial attention performance

Background

Previous research has shown that spatial performance (e.g. navigation, visuospatial memory, attention) can be influenced by acute stress; however, studies have produced mixed findings sometimes showing an improvement after stress, other times showing impairment or no overall effect. Some of these discrepancies may be related to: the type of stress system activated by the stressor (sympathetic adrenal medulla [SAM] or hypothalamic-pituitary-adrenocortical [HPA]); whether cortisol responders vs. nonresponders are analyzed subsequent to main effects; and sex differences in stress responses. In the present study, we examine the influence of HPA activation from an acute laboratory stressor (Socially Evaluated Cold Pressor test [SECPT]) on performance during two spatial tasks: Useful Field of View (UFOV; a measure of spatial attention) and virtual reality (VR) navigation. We assigned 31 males and 30 females to either the SECPT or a Non-Stress condition prior to the two spatial tasks. Cardiovascular measures including heart rate and blood pressure, and salivary cortisol biosamples were obtained at specific time points.

Results

Participants in the Stress condition showed increases in heart rate, systolic and diastolic blood pressure indicating sympathetic adrenal medulla (SAM) axis activation. Stress also led to increases in salivary cortisol, suggesting hypothalamic-pituitary-adrenocortical (HPA) activation. Stress did not influence overall performance in the spatial attention UFOV or the VR navigation task. However, a sex difference in spatial attention was detected when participants were divided into Stress-cortisol responders and non-responders in the UFOV task. Male Stress-cortisol responders (n = 9) showed better UFOV accuracy than female Stress-cortisol responders (n = 6); no sex differences were found among the Non-Stress control group. Furthermore, for females in the stress condition (n = 14), higher cortisol responses were associated with lower spatial attention performance.

Conclusions

Socially Evaluated Cold Pressor stress resulted in no change in speed or accuracy in a VR navigation task. For the spatial attention task, the SECPT led to a sex difference among Stress-cortisol responders with males showing improved accuracy over females. The relationship between HPA activation and prefrontal cortex activity may be necessary to understand sex differences in spatial attention performance.

Effect of Ustukhuddus Alavi, a multi-herbal product, on the cognitive performance of adolescent female students

ETHNOPHARMACOLOGICAL RELEVANCE

Ustukhuddus Alavi is a polyherbal formula which is introduced by Persian medicine scholars. It is traditionally used to treat brain disorders and is claimed to do so by preprocessing and cleansing the waste products from the brain. According to Persian medicine, the disposal of brain waste products is necessary for optimal cognitive performance.

AIM OF THE STUDY

Sustaining optimal cognitive performance is crucial for ideal quality of life and higher academic achievements in high school students. The objective of this study was to determine the effects of this multi-component herbal product on the cognitive performance and salivary cortisol levels of adolescent female students.

MATERIALS AND METHODS

The effect of a 6-week randomly assigned Ustukhuddus Alavi versus placebo administration on cognitive performance was assessed by the paced auditory serial addition test (PASAT) at the baseline and after the 3- and 6-week intake of Ustukhuddus Alavi or placebo and the one-month follow-up in 86 healthy female high school students in grades 10 and 11. Additionally, we measured the levels of salivary cortisol of the students pre- and post-intervention.

RESULTS

Significant mean difference between the Ustukhuddus Alavi and placebo groups in three of the paced auditory serial addition test (PASAT) subscales, namely mental health (p-value = 0.006), sustained attention (p-value = 0.001) and mental fatigue (p-value = 0.001), were observed after six weeks. We also found a significant difference between the mean salivary cortisol level of the two groups after the intervention (p-value = 0.047).

CONCLUSIONS

These findings reveal that the intake of the multi-ingredient herbal product Ustukhuddus Alavi for six weeks can be helpful for cognitive function and cortisol levels in female high school students. These positive effects seem to be related to the increase in sustained attention and the decrease in mental fatigue.

Diurnal pattern of salivary alpha-amylase and cortisol under citric acid stimulation in young adults

Background

Saliva composition has diurnal variations. Citric acid stimulation plays a major role in the change of salivary flow rate and salivary composition. However, diurnal variations and sex differences in salivary alpha-amylase (sAA), pH, salivary flow rate (SFR), and salivary cortisol before and after citric acid stimulation remain unclear.

Methods

We recruited 30 healthy volunteers, including 15 women (24.7 ± 1.0 years old) and 15 men (25.3 ± 1.3 years old). At four time points (T1, 7:00; T2, 10:00; T3, 16:00; and T4, 20:00), saliva was collected from healthy volunteers before and after citric acid stimulation; and sAA, pH, SFR and salivary cortisol were measured and compared between men and women.

Results

There were circadian fluctuations in sAA activity, SFR, pH, and cortisol level both before and after citric acid stimulation, and the diurnal fluctuations of these indexes were not affected by citric acid stimulation. There were significant differences in salivary cortisol between men and women before and after acid stimulation in T1. Neither SFR nor pH showed sex-related differences before or after acid stimulation. The variation trend of sAA activity was contrary to that of cortisol, with a significant negative correlation.

Conclusions

Our data suggest that sAA and cortisol showed diurnal fluctuation, and the variation characteristics of male and female under resting state and acid stimulation were basically the same. The variation trend of salivary alpha-amylase activity was opposite to that of cortisol, with significant negative correlation. Our findings may enable the selection of the correct sampling time for research and the selection of appropriate sampling strategies in studies investigating chronic psychosocial conditions.

Exploring the relationship between meaningful conditioned pain modulation and stress system reactivity in healthy adults following exposure to the cold pressor task

BACKGROUND

The sympathetic nervous system (SNS) and hypothalamic-pituitary-adrenal (HPA) axis have been implicated in conditioned pain modulation (CPM). As there has recently been a push to identify meaningful CPM responses based on ± 2 SEM of the test stimulus, we sought to evaluate if meaningful CPM had relationships with both SNS and HPA axis reactivity.

METHODS

50 university-aged healthy participants (25 males, 25 females) underwent evaluation of pressure pain detection threshold (PPDT), conditioned pain modulation (CPM), galvanic skin response (GSR) and salivary cortisol before and after a cold pressor test (CPT). Meaningful CPM was evaluated based on change ±2 SEM of baseline PPDT to classify participants as experiencing inhibition of pain, facilitation, or non-response.

RESULTS

As a group, there were no significant changes in PPDT or salivary cortisol after exposure to noxious cold. GSR was significantly elevated from baseline values during the CPT, and 10 min after (p < 0.001). When meaningful CPM was assessed, only 30% of participants experienced inhibitory CPM. Within this group, there was a large positive correlation ranging from r = 0.63 to 0.69 (p < 0.01) between CPM and the absolute change in GSR from baseline to immersion, and the immediate 5 min after immersion.

CONCLUSIONS

This work continues to support the growing body of literature suggesting that CPM is not universally experienced. Inhibitory CPM may be associated with an increase in SNS activity for healthy participants in reaction to noxious cold. Future work is required to ascertain individual characteristics (e.g., age, sex) that relate to CPM responses.

The effect of oral contraceptive use on cortisol reactivity to the Trier Social Stress Test: A meta-analysis

BACKGROUND

Some research suggests that oral contraceptive pills (OCPs) blunt the cortisol stress response, thus OCP users are often excluded from stress research. The current study examined changes in salivary cortisol among females taking OCPs and naturally cycling (NC) females after exposure to the Trier Social Stress Test (TSST).

METHODS

The literature search included the terms "oral contraceptives" OR "oral contraception" OR "birth control" OR "birth control pill" AND "Trier Social Stress Test" OR "TSST" AND "cortisol" OR "salivary cortisol." A total of 14 studies with 36 independent samples were included in the meta-analysis. Participant information, including pre- and post- TSST measures of salivary cortisol, and subgroup (i.e., OCP or menstrual cycle phase), were extracted. Additional study characteristics including age, length of stressor, type of OCP, time of day the cortisol samples were collected, and type of cortisol assay used were also considered.

RESULTS

Findings from the current meta-analysis indicated that changes in salivary cortisol in NC participants following the TSST, D = 4.31, SE = 0.53, 95% CI = 3.27, 5.35, were greater than the changes observed in participants on OCPs D = 1.50, SE = 0.30, 95% CI = 0.91, 2.09. Study effects were heterogeneous, Fisher's Z = 10.87, Q = 620.57, p = < 0.001. Between-phase analyses were also conducted.

CONCLUSIONS

Results demonstrate that OCPs blunt cortisol reactivity relative to NC females. There was significant heterogeneity, except between OCP and follicular phase groups. Implications for research design and methodology are discussed.

Cortisol Levels in Childhood Associated With Emergence of Attenuated Psychotic Symptoms in Early Adulthood

BACKGROUND

In individuals at clinical high-risk for psychosis, elevated cortisol levels predict subsequent onset of psychotic disorder. However, it is unclear whether cortisol alterations are evident at an earlier clinical stage and promote progression of psychosis expression. This study aimed to address this issue by investigating whether cortisol levels in childhood were associated with the emergence of attenuated psychotic symptoms in early adulthood. In exploratory analyses, we examined whether cortisol and psychosocial stress measures interacted in predicting attenuated psychotic symptoms.

METHODS

A sample of children (N = 109) enriched for psychosis risk factors were recruited at age 9-12 years and assessed at age 11-14 years (T1) and 17-21 years (T2). Measures of psychopathology, psychosocial stressors, and salivary cortisol were obtained at T1. Attenuated psychotic symptoms were assessed at T2 using the Prodromal Questionnaire.

RESULTS

Diurnal cortisol (β = 0.915, 95% CI: 0.062-1.769) and daily stressors (β = 0.379, 95% CI: 0.034-0.723) at T1 were independently associated with total Prodromal Questionnaire scores at T2 after accounting for demographic factors and T1 psychopathology. Exploratory analyses indicated a significant interaction between T1 diurnal cortisol and daily stressors (β = 0.743, 95% CI: 0.081-1.405), with the highest predicted T2 total Prodromal Questionnaire scores occurring when both diurnal cortisol and daily stressors were increased.

CONCLUSIONS

Our findings suggest that daily stressors and elevations in diurnal cortisol in late childhood/early adolescence increases risk for developing attenuated psychotic symptoms. These findings emphasize the importance of assessing environmental and biological risk factors for psychosis during neurodevelopmentally vulnerable time periods.

Therapeutic Riding or Mindfulness: Comparative Effectiveness of Two Recreational Therapy Interventions for Adolescents with Autism

Therapeutic riding (THR) and HeartMath (HM) mindfulness-based interventions have promise for reducing stress in adolescents with autism spectrum disorder. In three 10-week periods, this study compared THR, HM, and control on salivary cortisol, self-reported stress, parent-reported social responsiveness, and heart-rate variability. This crossover design included 27 participants (12-21 years) randomly assigned to order of intervention. Findings suggest that HM and THR manualized protocols are equally beneficial in decreasing cortisol levels immediately following a session, but HM sessions had more impact on heart-rate variability. There was no significant effect on follow-up cortisol levels within a week after either intervention, but THR had more impact on decreasing some self-reported stressors.

Association of cancer caregiver stress and negative attribution style with depressive symptoms and cortisol: a cross-sectional study

PURPOSE

We examined the effect of informal cancer caregiver stress and negative attribution style (NAS) on depressive symptoms and salivary cortisol.

METHOD

The sample came from a hospital bone marrow unit and caregiver support organizations and included 60 informal cancer caregivers (51.7% partners) of individuals with cancer (provided care for a median of 27.5 h per week for 12 months) and 46 non-caregiver participants. In this cross-sectional study, participants completed questionnaires assessing NAS and depressive symptoms and provided saliva samples to measure cortisol.

RESULTS

Linear regressions demonstrated that cancer caregiver stress (p = 0.001) and the cancer caregiver stress by NAS interaction (p = 0.017), but not NAS alone (p = 0.152), predicted depressive symptoms. Caregivers independent of their NAS and non-caregivers high in NAS reported high depression while non-caregivers low in NAS reported low depression. Neither cancer caregiver stress (p = 0.920) nor NAS alone (p = 0.114), but their interaction, predicted cortisol (p = 0.036). Higher NAS was associated with a higher cortisol in both groups while non-caregivers had higher cortisol than caregivers.

CONCLUSIONS

If the findings can be replicated, consideration of NAS in existing interventions to support informal cancer caregivers in managing chronic stress appears warranted.

Habituation of salivary cortisol and cardiovascular reactivity to a repeated real-life and virtual reality Trier Social Stress Test

BACKGROUND

Although the Trier Social Stress Test (TSST) constitutes a valid paradigm for social stress induction, less is known about the effects of a virtual reality (VR) TSST on short- and long-term hypothalamic-pituitary-adrenal (HPA) axis and sympathetic-adreno-medullar (SAM) axis responses. Hence, this study set out to evaluate reactivity and habituation of self-reported stress and HPA and SAM reactivity in a real TSST and VR-TSST when compared to a placebo TSST.

METHOD

Sixty-eight healthy young adults (50% female) were randomly assigned to either a real TSST, a VR-TSST, or a placebo TSST, all of which were conducted three times (one day and one week post initial exposure). Social presence, self-reported stress, salivary cortisol, heart rate (HR), and heart rate variability (HRV) were analyzed using ANOVAs and multilevel models.

FINDINGS

On the first exposure, both the real and VR-TSST showed significantly stronger cortisol and cardiovascular responses than the placebo. On the second visit, the cortisol response was still significantly high-and the HRV response low-for the real and VR-TSST. The third visit resulted in HR, HRV, and cortisol responses comparable to the placebo group. Furthermore, the real TSST induced more self-reported stress than the placebo on all three visits, the VR-TSST only on the first two visits. Social presence was stable across conditions and had no association with stress markers.

CONCLUSION

These findings imply that the replicability of stress exposures at shorter intervals seems problematic for the traditional TSST, and for the VR-TSST.

How to assess and interpret everyday life salivary cortisol measures: A tutorial on practical and statistical considerations

Salivary cortisol has been the central marker in psychoneuroendocrinological stress research for three decades. Given the technological possibilities to assess data in ecologically valid circumstances, many studies have implemented longitudinal assessments of salivary cortisol in study participants' everyday life. Such studies bear the potential to understand real-life associations of cortisol with psychological traits, states, and health variables. Furthermore, changes in the neuroendocrine regulation and in cortisol reactivity can be used to evaluate the effects of behavioral interventions in real-life circumstances. While standardized paradigms have been developed to measure cortisol in laboratory settings, there is high heterogeneity in the assessment, statistical processing, and interpretation of everyday life cortisol measures. This methodological tutorial aims at summarizing important knowledge which had been accumulated during the past two decades and which could be used to set up an ambulatory assessment study focusing on salivary cortisol in everyday life. Practical advice for possible strategies at all stages of the research process is outlined in detail. Additionally, an example on how to statistically process cortisol data in a multilevel framework (including syntax) is provided. In these analyses, we investigate within- and between-person research questions regarding the association between stress and cortisol in daily life. Thus, the present work (a) can be used as tutorial for setting up everyday life studies focusing on the assessment of salivary cortisol, and (b) can be useful to avoid inconsistencies in study planning, data assessment and data processing in future studies.

Diurnal Salivary Cortisol in Sarcopenic Postmenopausal Women: The OsteoLaus Cohort

Sarcopenia, similar to hypercortisolism, is characterized by loss of muscle mass and strength. Cortisol circadian rhythm changes with aging (blunted late-day nadir values) were suggested to contribute to this decline. We aimed to explore the relationship between diurnal salivary cortisol values and sarcopenia diagnosis and its components in postmenopausal women. This is a cross-sectional study within the OsteoLaus population-based cohort in Lausanne (Switzerland). Participants had a body composition assessment by dual X-ray absorptiometry (DXA), a grip strength (GS) measure, and salivary cortisol measures (at awakening, 30 min thereafter, 11 AM (sc-11AM) and 8 PM (sc-8PM)). Associations between salivary cortisol and sarcopenia diagnosed by six different criteria (based on appendicular lean mass (ALM) assessed by DXA, and muscle strength by GS), and its components, were analyzed. 471 women aged > 50 years (63.0 ± 7.5) were included. Various definitions identified different participants as sarcopenic, who consistently presented higher salivary cortisol at 11 AM and/or 8 PM. There were no associations between salivary cortisol levels and ALM measures, either absolute or after correction to height squared (ALM index) or body mass index. GS was inversely correlated to sc-11AM (r = - 0.153, p < 0.001) and sc-8PM (r = - 0.118, p = 0.002). Each 10 nmol/l increase of sc-11AM, respectively sc-8PM, was associated with a GS decrease of 1.758 (SE 0.472) kg, respectively 2.929 (SE 1.115) kg. In postmenopausal women, sarcopenia is associated with higher salivary cortisol levels at 11 AM and 8 PM. An increase of daily free cortisol levels in the physiological range could participate to sarcopenia development by decreasing muscle function in postmenopausal women.

Effects of psychological, sensory, and metabolic energy prime manipulation on the acute endocrine stress response in fasted women

The stress response supports survival through energy mobilization. Paradoxically, a low blood glucose level dampens the endocrine stress response, and sugar consumption prior to stress restores it. Thus, energy availability may play a causal role in the endocrine stress response. Yet, it has never been tested whether sweet taste or expectations towards a drink content modulate the stress response. We investigated the potential role of sweetness, energy load and expectations towards energy load of a drink consumed prior to stress in restoring stress reactivity after fasting. N = 152 women (meanage=21.53, sdage=2.61) participated in the Trier Social Stress Test for groups in the morning after an overnight fast. Prior to stress induction, participants consumed a drink containing saccharose (sugar, n = 51), an equally sweet drink containing non-caloric sweetener (sweetener, n = 46), or water (n = 56). Additionally, participants in the sugar and sweetener group (n = 97) were informed whether or not their drink contained any calories (energy prime), which was deceptive in 50% of the cases. Eight salivary cortisol (-30, -20, -10, 0, +12, +25, +35, +45 min) and three blood glucose samples (-30, 0, +25 min) were assessed throughout the experiment. The effects of the experimental manipulations on cortisol trajectories were tested using multilevel mixed models. We found that compared with water, sugar and sweetener both significantly increased cortisol stress reactivity and with comparable intensity. However, our sensitivity analysis revealed a significant effect of sugar on cortisol trajectories compared to water and to sweetener. Drink-induced changes in blood glucose concentration were not associated with increases in cortisol. The energy prime did not affect the stress response. Overall, we could replicate the boosting effect of sugar consumption in a female sample after 8 h of fasting. The specific contribution of sweet taste and metabolic hormones to this boosting effect should be tested more rigorously in sex-balanced designs in the future.

Salivary cortisol and eye temperature changes during endurance competitions

Background

The purpose of this study was to investigate the usefulness of salivary cortisol (SC) and eye temperature measured by infrared thermography (IRT^ET) as biomarkers to manage competitions more effectively and monitor horse welfare in endurance competitions. Based on previous studies, it was hypothesised that pre-exercise baseline SC and IRT^ET would be higher in younger or less experienced horses, and that post-exercise variation from baseline would be higher in the top finishers.

Results

Salivary cortisol measured in 61 competing at qualifier 40 km and 80 km rides showed an abrupt variation (93–256% rise) of the baseline SC levels [median ± interquartile range (IQR) = 0.27 ng/dl ± 0.36] obtained at the Pre-Inspection (PI) into Vet Gate (VG)1 independently of the covered distance, but modest or even lower in the subsequent Vet Gates, e.g. VG2 or VG3. The IRT^ET measured concomitantly in 16 horses showed significant (p < 0.05) higher levels at the PI in less experienced horses participating in the 40 km ride (median ± IQR = 35.7 °C ± 1.4) than their counterparts in the 80 km ride (median ± IQR = 35.0 °C ± 1.5), but not SC. Baseline SC levels at the PI of horses classifying in the Top5 in the 40 km ride category were significantly (p < 0.05) higher median ± IQR = 0.90 ng/ml ±0.61) when compared to horses positioned from 10th position on (median ± IQR = 0.16 ng/ml ±0.40). A lower IRT^ET in the PI was correlated with better placement (p < 0.05) and those in the Top5 (median ± IQR = 33.9 °C ± 0.0) had a significantly (p < 0.5) higher variation (+ 10.65%) into the last VG.

Conclusion

Pre-exercise baseline IRT^ET levels, but not SC, were higher in less experienced horses in the 40 compared to their counterparts in the 80 km ride competitions. SC and IRT^ET showed different indications according to the competition. In the40 km ride competition, higher baseline pre-exercise SC levels seemed to be linked to a better classification outcome. In contrast, in the 80 km ride horses, the higher IRT^ET variation from pre-exercise into final Vet Gate was the parameter associated with a better performance. A more controlled environment and a larger sample are needed to confirm these results and monitor horse welfare in competitions.

Does salivary cortisol secretion mediate the association of work-related stressors with workers' depression?

PURPOSE

The purpose of this study was to verify the mediating role salivary cortisol intensity plays between work organization conditions and depression. This study simultaneously considered psychological and physiological (salivary cortisol) stress indicators on workers' depression in a single model.

METHODS

We relied on cluster sampling of 341 workers in 34 Quebec establishments. Five saliva samples (on awakening, 30 min after awakening, at 2:00 p.m., 4:00 p.m., and bedtime) were collected per day. The weekly collection period spanned a period of 3 days (1 day off and 2 work days). We evaluated the main effects of work organization conditions on salivary cortisol intensity and depression, as well as the mediation effect of salivary cortisol intensity between work organization conditions and depression. To adjust for design effects, the direct and indirect (mediation) associations between the variables were evaluated while accounting for the non-independence of the data.

RESULTS

Skill utilization and job insecurity were associated with salivary cortisol intensity, while psychological demands and job insecurity were associated with higher depression levels. Work-related variables were not found to have an indirect effect on depression via worker's salivary cortisol (AUC) intensity.

CONCLUSION

Work-related stressors examined in this study did not indirectly affect worker's depression levels. Additional studies are necessary to be able to identify all work-related stressors that could potentially increase worker's depression levels through salivary cortisol.

Patterns of poverty across adolescence predict salivary cortisol stress responses in Mexican-origin youths

Poverty is a chronic stressor associated with disruptions in psychophysiological development during adolescence. This study examined associations of chronic poverty and income changes experienced from pre- to mid-adolescence with hypothalamic-pituitary-adrenal (HPA) axis stress responses in late adolescence. Participants (N = 229) were adolescents of Mexican-origin (48.7% female). Household income (converted to income-to-needs ratios) was assessed annually when children were 10-16 years old. At 17 years, adolescents completed Cyberball, a social exclusion simulation task while undergoing a functional magnetic resonance imaging scan. Saliva samples were collected prior to and five times over a 50-minute period following the scan, from which salivary cortisol was assayed. Results showed that differential trajectories of poverty from ages 10-16 predicted HPA axis activity at age 17. Relative to others, distinct HPA suppression (hyporeactivity) was demonstrated by youth who started adolescence in deep poverty and were still living in poverty at age 16 despite experiencing some income gains. Youth from more economically secure families evinced typical cortisol increases following the lab stressor. These results suggest that subsequent HPA functioning varies as a function of economic status throughout adolescence, and that efforts to increase family income may promote healthy HPA functioning for youths in the most impoverished circumstances.

Long-term cortisol levels in hair of children and adolescents with Prader-Willi Syndrome

CONTEXT

Prader-Willi syndrome (PWS) is characterized by hypothalamic dysfunction. In children with PWS, stress-induced central adrenal insufficiency (CAI) has been described, however, daily life cortisol production may be normal. Hair cortisol concentration (HCC) is a marker of long-term systemic cortisol production. Cortisol awakening response (CAR) is the increase in cortisol level after awakening. A negative CAR might suggest hypothalamic-pituitary-adrenal (HPA)-axis reactivity problems. Little is known about HCC and CAR in children with PWS.

OBJECTIVE

To investigate long-term cortisol levels in hair and CAR in children with PWS.

DESIGN

Cross-sectional study.

PATIENTS

41 children with PWS.

SETTING

Dutch PWS Reference Center.

MAIN OUTCOME MEASURES

HCC and salivary cortisol measured by LCMS.

RESULTS

Median (IQR) HCC was 1.90 (1.02-3.30) pg/mg at a median (IQR) age of 14.5 (8.20-19.0) years, with median HCC in age-matched references being 2.63 pg/mg. Five patients (13.2%) had HCC < 2.5th percentile for age and these patients had a repeatedly negative CAR. Median HCC was significantly lower in patients with negative CAR than in patients with normal CAR (1.00 (0.22-1.59) vs. 2.25 (1.47-3.26) pg/mg, p = 0.007). One patient had both HCC < 2.5th percentile and repeatedly low morning salivary cortisol levels and negative CAR, and was diagnosed with adrenal insufficiency by overnight metyrapone test.

CONCLUSIONS

HCC were normal in the majority of children with PWS. Our data suggest that children with HCC < 2.5th percentile and (repeatedly) negative CAR might possibly have adrenal insufficiency or delayed HPA-axis responsiveness.

Gut microbiota diversity but not composition is related to saliva cortisol stress response at the age of 2.5 months

Human brain and intestinal microbes reportedly maintain a constant bidirectional connection through diverse neural, endocrine, immune, and metabolic pathways. Increasing evidence indicates that this communication system, referred to as microbiota-gut-brain axis, enables the gut microbes to influence several aspects of brain function and behavior, including hypothalamic-pituitary-adrenal (HPA) axis stress responses, and on the other hand, stress can affect gut microbiota. However, the role of gut microbiota in the HPA axis functioning in humans remains to be specified especially in early life. This study aimed at identifying the potential link between the cortisol stress response and the gut microbiota at the age of 2.5 months. Fecal microbiota profiles were acquired by 16S rRNA gene sequencing, while salivary cortisol responses after an exposure to a mild acute stressor represented the HPA axis reactivity. We observed that a blunted cortisol stress response was weakly associated with a diverse gut microbiota diversity at the age of 2.5 months. Gut microbiota composition was not associated with cortisol stress responsiveness, but rather with covariates, i.e. factors that influence gut microbiota composition and colonization.LAY SUMMARYThis exploratory study aimed at identifying possible links between cortisol stress responses and fecal microbiota composition in early infancy. In a well-characterized study population of 2.5-month-old infants, we observed that an attenuated cortisol stress responsiveness after a mild stressor was weakly associated with a diverse fecal microbiota. Our results suggest that the gut microbiota composition is associated with environmental factors, such as delivery mode and number of siblings, rather than with cortisol stress responsiveness, in this age group.

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.