Lower Salivary Cortisol Levels Research Articles

Comprehensive assessment of memory function, inhibitory control, neural activity, and cortisol levels in late pregnancy.

A considerable proportion of women subjectively perceive a detriment to their cognitive capacity during pregnancy, with decreased memory functions being the most frequently self-reported concerns. However, objective investigation of these perceived cognitive deficits has yielded inconsistent results. This study focused on memory functions during late pregnancy using multiple tasks designed to assess various memory indices, for example, working memory, learning rate, immediate recall, proactive and retroactive interference, delayed recall, retrieval efficiency, visuospatial constructional ability, recognition, and executive function. Additionally, sustained attention and inhibitory control were examined using a combined recognition stop-signal task. Electrophysiological brain activity during this task was recorded using a 128-channel electroencephalographic-event-related potential system. Salivary cortisol levels were assessed both prior to and following the experimental session. In contrast to the widely held belief, results demonstrated that women in late pregnancy did not exhibit a decline in their performance across the various memory tests. In terms of accuracy, there was not a single task in which poorer performance was found for pregnant women. The quality of memory performance was comparable, and in some cases even superior, among women in the pregnancy group. On the stop-signal task, pregnant women exhibited significantly better performance, and their electrophysiological data revealed greater centrally distributed P300 amplitude to "stop" signs, which may signify an enhanced neural efficiency in the domains of inhibitory executive control. Endocrine results revealed that pregnant women exhibited significantly lower levels of salivary cortisol, suggesting an attenuation of hypothalamic-pituitary-adrenocortical axis activity, which may contribute to the optimization of fetal development and growth.

Adult age differences in the psychophysiological response to acute stress

Age-related differences in the psychophysiology of the acute stress response are poorly understood given the limited number of studies and the high heterogeneity of findings. The present study contributes by investigating age differences in both the psychological and physiological responses to acute stress in a sample of healthy younger (N = 50; 18–30; Mage = 23.06; SD = 2.90) and older adults (N = 50; 65–84; Mage = 71.12; SD = 5.02). Specifically, the effects of psychosocial stress (i.e., age-adapted Trier Social Stress Test) were investigated at numerous timepoints throughout the stress response phases (i.e., baseline, anticipation, reactivity, recovery) on cortisol, heart rate, subjective stress, and anticipatory appraisal of the stressful situation. The study was conducted in a between-subject (younger vs. older) cross-over (stress vs. control) design. Results revealed age-related differences in both physiological and psychological variables: older adults had overall lower salivary cortisol levels in the stress and control conditions and lower stress-induced cortisol increase (i.e., AUCi). In addition, older adults’ cortisol reactivity was delayed compared to younger adults. Older adults showed a lower heart rate response in the stress condition while no age differences were observed in the control condition. Finally, older adults reported less subjective stress and a less negative stress appraisal during the anticipation phase than younger adults, which could potentially explain lower physiological reactivity in this age group. Results are discussed in relation to the existing literature, potential underlying mechanisms, and future directions for the field.

Prevalence and prediction of PTSD and depression in mothers of children surviving a motor vehicle crash

ABSTRACT Introduction: Few studies have examined the psychopathological consequences for parents of children who were survivors of a motor vehicle crash (MVC). This study assessed the impact of dissociation and peritraumatic distress on the severity of PTSD and post-traumatic major depressive episode (MDE) symptoms in mothers during the first years after the MVC and the role that cortisol response might play in this association. Methods: 125 mothers were included. Peritraumatic distress and dissociation were assessed. Morning salivary cortisol was tested at the baseline. Participants were assessed for a probable diagnosis of PTSD and MDE at 5 weeks, 6 months and 12 months. Results: At 5 weeks, 12 (13.6%) mothers exhibited probable PTSD. During the first year, the PCL score was higher when the (i) Peritraumatic Distress Inventory (PDI) score increased and (ii) the Peritraumatic Dissociation Experience Questionnaire (PDEQ) score increased. Cortisol levels were lower when the PDI score increased. Conclusion: This is the first study to assess the mothers of MVC survivors for one year following the trauma. We confirm that peritraumatic responses are useful for predicting the severity of PTSD symptoms. These results could encourage the implementation of follow-up programmes not only for survivors but also for their mothers. HIGHLIGHTS Mothers of children involved in motor vehicle accident are at risk for developing PTSD. Peritraumatic responses (distress and dissociation) are associated to the severity of PTSD symptoms. Low salivary cortisol levels were associated with high peritraumatic distress.

Laser Acupuncture Analgesia on Postpartum Low Back Pain: A Prospective Randomized Controlled Study

BackgroundUnresolved postpartum LBP may affect women...s physical and psychological health. AimTo investigate the analgesic effects of laser acupuncture therapy (LAT) for postpartum LBP. MethodPostpartum women with LBP were recruited and randomly assigned to the intervention group or the control group from November 2017 to July 2018. The participants in the intervention group received LAT and standard care. The participants in the control group received only standard care. The primary outcome was the Visual Analogue Scale for LBP. Secondary outcomes were limitation of daily activities and physical activity; perceived stress scale; and salivary cortisol values. ResultsIn all, 106 participants were recruited and assigned to the intervention group or the control group. As compared with the control group, the participants in the LAT group had significantly lower intensity of LBP (mean ± SD: 1.21 ± 0.99 vs 3.25 ± 1.14; p < .001), limitations of daily activities (mean ± SD: 3.17 ± 2.09 vs 10.40 ± 4.72; p < .001) and physical activity (mean ± SD: 3.04 ± 2.17 vs 9.79 ± 4.71; p < .001), perceived stress (mean ± SD: 26.13 ± 3.97 vs 28.85 ± 4.26; p = .001), and salivary cortisol levels (mean ± SD: 0.194 ± 0.131 vs 0.280 ± 0.234; p = .02) post-intervention. ConclusionsFor postpartum LBP, LAT combined with standard care had greater analgesic efficacy, lower perceived stress, lower limitations of daily activities and physical activity, and lower salivary cortisol levels than standard care alone.

Do prepubertal hormones, 2D:4D index and psychosocial context jointly explain 11-year-old preadolescents’ involvement in bullying?

BackgroundBullying is a type of aggressive behavior that occurs repeatedly and intentionally in school environments and where there is a power imbalance. The main objective of this study was to analyze the association that hormones and the psychosocial context jointly have with bullying behavior. MethodParticipants were 302 11-year-old preadolescents from the Gipuzkoan cohort of the INMA Project. Bullying was assessed using the Olweus Bully/victim Questionnaire. Prenatal sexual hormones were assessed by calculating 2D:4D ratio and in order to measure prepubertal testosterone and cortisol levels saliva samples were collected within a week of each other. Additionally, various psychosocial factors were evaluated: executive function, family context, school environment and social context. To analyze our complex hypothesis, six metamodels were tested using structural equation modeling. ResultsIn relation to victims, results showed that victimization was related to worse school environment’ perception in boys, and higher stress and conflict in the family in girls. In the case of their involvement in bullying as a bully, lower salivary cortisol levels, worse school environment’ perception and lower peers and social support was related to being more frequently involved as a bully in boys, while having more family stress and conflict was related with being a bully in girls. ConclusionsThis approach makes it possible not only to explore the different biological and psychosocial factors affect bullying behavior, but also to explore associations between the predictor variables.

Adverse childhood experiences and diurnal cortisol patterns in older people in England

Adverse childhood experiences (ACE) are associated with HPA axis dysregulation at younger ages, but there is scarcity of evidence for this association at older ages. To add to our knowledge of the lifetime impact of ACE on HPA axis function, we examined whether ACE were associated with diurnal cortisol patterns in a national sample of 587 participants (356 women) aged 55–79 years from the English Longitudinal Study of Ageing (ELSA). We conducted descriptive analyses and estimated sex-specific robust regression models of the associations between the 8-item summary ACE score and four measurements of salivary cortisol over a 24-h cycle (upon waking, 30 min later, at 7 pm, and at bedtime) as well as the cortisol awakening response (CAR) and the diurnal cortisol slope. Our models were adjusted for age, then for childhood socioeconomic position and finally for adult socioeconomic position. In men, we found significant differences that were independent of covariates, with more ACE being associated with lower salivary cortisol levels on waking, a greater CAR, and a flatter diurnal cortisol slope. In women, we observed a graded association between ACE and increased 7 pm salivary cortisol levels. Our findings indicate that childhood adversity is related to HPA axis in older people, especially men. The chronological distance (on average >50 years) between ACE and salivary cortisol levels suggests the existence of a lifelong association between childhood adversity and HPA axis and neuroendocrine function. Notwithstanding sex differences, based on our findings we suggest that HPA axis dysregulation could be a pathway that mediates the association between ACE and chronic disease later in life.

Introducing nature at the work floor: A nature-based intervention to reduce stress and improve cognitive performance.

Although a growing body of research has shown that exposure to nature has restorative effects on human health, the potential beneficial effects of nature-based interventions in the working environment are still underexplored. We performed a randomized controlled study with a nature-based program during working hours. We enrolled employees, randomized the participants into two groups being an intervention and a control group. Twice a week for three consecutive weeks, the intervention group participated in nature-based activities for 2h. The primary outcomes were cognitive performance, burnout assessment, salivary cortisol levels, and continuous stress levels. We performed intervention-response analyses using mixed-effects models that included random effects for each participant across the different examinations. Compared to the control group (n=20), the intervention group (n=25) participating in the nature-based program had a lower Burnout Assessment Tool score (-14.9% CI-16.2 to -14.3, difference; p<0.001), lower salivary cortisol levels (-29.3% CI-34.7 to -25.3; p<0.001) and higher visual information processing speed (7.4% CI6.9-8.0; p<0.001). Selective attention of the participants that participated in the nature-based program improved during the interventions (-10.6 CI-19.6 to -6.9, p=0.045), compared to the controls. This study provides novel evidence that exposure to nature during work hours reduces stress and improves cognitive performance. The trial is registered with ClinicalTrials.gov, number: NCT04111796.

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

ContextPrader-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. ObjectiveTo investigate long-term cortisol levels in hair and CAR in children with PWS. DesignCross-sectional study. Patients41 children with PWS. SettingDutch PWS Reference Center. Main outcome measuresHCC and salivary cortisol measured by LCMS. ResultsMedian (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. ConclusionsHCC 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.

A longitudinal study of perceived stress and cortisol responses in an undergraduate student population from India.

Young adults entering college experience immense shifts in personal and professional environments. Such a potentially stressful event may trigger multiple psychological and physiological effects. In a repeated-measures longitudinal survey (N = 6 time-points) of first year cohort of residential undergraduate students in India, this study evaluates multiple psychological parameters: PSS14 (Perceived Stress Scale), K10 (distress scale) and positive mood measures, along with salivary cortisol levels. We find that compared to women, men showed significantly lower levels of salivary cortisol and also a decrease in perceived stress (PSS14) and distress (K10) with time. By contrast, women reported similar perceived stress and distress levels over time but had higher cortisol levels at the end of the academic year. Academic stress was reported by the students to be the most important stressor. This study highlights notable gender-/sex-differences in psychological and physiological stress responses and adds a valuable longitudinal dataset from the Indian undergraduate student cohort which is lacking in literature.

Infant diurnal cortisol predicts sleep.

The sleep-wake system is immature at birth and develops in parallel with the hypothalamic-pituitary-adrenal axis, a biological stress system of which the end product is cortisol. Perturbations in one system during infancy can maladaptively influence the maturation of the other system, leading to lasting sleep and cortisol system dysregulation and heightening the risk of enduring health problems. To better understand the early interplay between these systems, we examined whether actigraphy-derived measures of night-time sleep duration and onset were associated with cumulative exposure to cortisol, indexed by hair cortisol concentration, in 12-month-old children. Overall, early sleep onset predicted lower hair cortisol above and beyond sleep duration, family income and chaos experienced at home. Furthermore, both sleep and cortisol levels vary day to day, and temporal dependencies between daily sleep and cortisol regulation are not well understood. Thus, we assessed how the sleep characteristics on a particular evening related to salivary cortisol levels the following day and how daytime and evening cortisol related to the sleep characteristics on the same night. Lower total exposure to cortisol on a particular day was related to longer night-time sleep duration the same night, but not sleep onset. Lower salivary cortisol levels on a given evening related to earlier sleep onset the same night, but not to night-time sleep duration. Sleep duration and onset on a given night were unrelated to total cortisol exposure the following day. Findings suggest that in early development, the day-to-day relation between sleep and cortisol is not bidirectional, but more driven by diurnal cortisol.

A Randomized Pilot Study of Rhythm-Based Music with Movement Strategies on Stress and Interaction Behaviors of Infant Caregivers

Consistent, prolonged, and nurturing interactions of a primary caregiver with an infant is necessary for optimal development of the infant. Lowering parental stress can promote positive caregiver-infant social interaction behaviors. Studies show that when caregivers use rhythm-based music and movement strategies during interactions with their infants, non-verbal communication, mutual attunement, and self-reported stress levels improve. The purpose of this pilot study was to determine caregiver benefits (stress hormones and positive interaction behaviors) when learning rhythm-based music with movement strategies while interacting with their infant. This was achieved through randomization of caregiver/infant dyads to a treatment (instructional intervention) or control condition with no instruction. Significantly lower salivary cortisol levels and lower salivary cortisol/DHEA ratio values pre-post were observed for the treatment condition as compared to control. These findings suggest that learning and using rhythm-based music and movement interventions are promising for lowering stress in caregivers. The impact of the intervention with families at risk due to stress-related environmental factors should be further investigated. In addition, observing social emotional behaviors and stress hormone levels of the infant is suggested.

Assessing Whether Meditation Improves Quality of Life for Adolescent Girls With Polycystic Ovary Syndrome: Protocol for a Randomized Controlled Trial.

BackgroundPolycystic Ovary Syndrome (PCOS) is a common endocrine condition characterized by irregular periods and hyperandrogenism. Adolescents with PCOS have impaired quality of life (QOL) and increased psychological distress. Transcendental Meditation (TM) is a well-established self-management strategy that has been used to improve stress and well-being. A meta-analysis of TM trials has shown beneficial effects on stress and blood pressure in adults. Recent data are suggesting that another self-management strategy called a mindfulness stress management program has a role in improving QOL in women with PCOS, but there are no studies in adolescents.ObjectiveThis study aims to evaluate the effect of TM on QOL and psychological distress in adolescent girls with PCOS.MethodsThis study is a randomized controlled trial that will be conducted over eight weeks at the Women’s and Children’s Hospital in Adelaide, South Australia, to determine the effect of TM on QOL and psychological distress in adolescent girls (aged 12-20 years) with PCOS. A total of 40 girls will be randomized into either the TM (n=20) or control group (n=20). The TM group will be asked to practice TM in a comfortable sitting position with the eyes closed, for 15 minutes twice daily over eight weeks. The control group will be asked to sit quietly for 15 minutes twice daily for eight weeks. The primary outcomes are any effects on improving QOL and psychological distress, and the secondary outcomes are any effects on lowering blood pressure and salivary cortisol levels.ResultsThe recruitment of study participants began in May 2019 and is expected to be completed by June 2020. It is expected that the adolescent girls with PCOS practicing TM over eight weeks will have a significant improvement in QOL and psychological distress compared to adolescents in the control group. Also, it is expected that adolescent girls in the TM group will have lower salivary cortisol levels and lower blood pressure.ConclusionsThis study will be the first to evaluate the effect of TM on QOL in adolescent girls with PCOS. The study will provide valuable information on a potential self-management strategy to improve QOL and well-being in adolescent girls with PCOS.Trial RegistrationAustralian New Zealand Clinical Trials Registry (ANZCTR) ACTRN1261900019010; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=376657&amp;isReview=trueInternational Registered Report Identifier (IRRID)PRR1-10.2196/14542

Relationship between Stress and Bone Density, Using Salivary Cortisol, in Young Adult Women

Although cortisol is believed to increase the osteoclast activity and accentuate bone resorption, few studies are available on cortisol and bone density. This study uses salivary cortisol to investigate the relationship thereof with bone density. Furthermore, we investigated whether the salivary Ca concentration could be an effective biomarker in bone evaluations using salivary cortisol. This study targeted 188 healthy female college students (18 - 25 years old). Calcaneus bone density (Speed of Sound: SOS) was measured using an ultrasonic bone density measurement device. Food intake was calculated via a food intake frequency survey. The saliva of subjects was collected in order to measure the cortisol concentration using an enzyme immunoassay, while the salivary Ca concentration was measured using an atomic absorption spectrophotometer. The relationship between salivary cortisol and SOS was not significant, with a correlation coefficient of -0.13, indicating a negative correlation and leading to the observation that those with lower salivary cortisol levels tended to have higher SOS. The relationship between salivary cortisol and salivary Ca concentration was not significant, with a correlation coefficient of +0.15, indicating a positive correlation and leading to the observation that those with higher salivary cortisol concentrations tended to have higher salivary Ca concentrations. No significant correlation was observed in the relationship between salivary Ca concentration and SOS. Because the cortisol in saliva responds more sensitively to acute stress than to chronic stress, this may not have had obvious significance. Furthermore, the salivary Ca concentration indicated large fluctuations, depending on the daily external conditions, particularly in terms of food; therefore, it is believed that the presence or absence of dietary intake before the survey affected the results. The above results suggest that bone density may decrease, while salivary Ca concentration may increase when salivary cortisol concentration increases due to stress.

Effects of Skin-to-Skin Care During Cesareans: A Quasiexperimental Feasibility/Pilot Study.

Introduction: Our aim was to describe feasibility and outcomes of skin-to-skin care (SSC) that began during cesarean surgery and continued, uninterrupted, for about 5 hours. We described maternal/newborn measures of physiologic stability and stress; maternal measures of comfort; maternal satisfaction with surgery and SSC; and exclusive breast milk feeding at discharge.Materials and Methods: We used a quasiexperimental, time-interrupted design and randomly assigned women to receive SSC that began during surgery (Group 1, intervention; n = 20) or after surgery, before transfer to recovery (Group 2, standard care; n = 20). We analyzed differences across time and for five observations: before transfer to the operating room (OR); in the OR, about 20 minutes after birth; in the recovery room, about 1 hour after admission; in the New Family Center (NFC), about 1 hour after admission; and in the NFC, about 2 hours after admission.Results: Group 1 began SSC an average of 0.89 minutes after birth and continued an average of 300 minutes and Group 2 began an average of 46 minutes after birth and continued an average of 126 minutes. Women who began SSC during surgery were more satisfied with the experience (p = 0.015) and had lower levels of salivary cortisol across time (p = 0.003). We found no negative effects on maternal or newborn measures of physiologic stability and no difference in exclusive breast milk feeding rates at discharge.Conclusion: Immediate and uninterrupted SSC during medically uncomplicated cesarean surgery is a feasible, low-cost intervention that can safely begin during surgery and continue, uninterrupted, for extended durations.

Salivary stress hormone response and performance in full competition after linear or undulating periodization training in elite powerlifters.

The purposes of this study were to determine differences in training loads and stress hormones among national level powerlifting competitors and the effect on performance. Thirteen experienced male powerlifters provided detailed training logs during the 8 weeks prior to a national competition. Participants were divided into linear (LP, N.=6) and undulating periodization (UP, N.=7) training groups. Following weigh-ins and after successfully completing the competition, participants provided saliva samples. LP resulted in lower levels of salivary cortisol (sC) (LP 4.27±0.71 nmols/L; UP 5.53±0.78 nmols/L) and higher testosterone-to-cortisol ratio (T:C) (LP 8.03±0.84 nmols/L; UP 5.23±1.41 nmols/L) compared to UP prior to competition. Following competition, both LP and UP groups had significant increases in salivary testosterone (sT) (LP 383.70±34.96 nmols/L; UP 376.62±38.17 nmols/L) and sC (LP 17.67±1.39 nmols/L; UP 18.17±1.46 nmols/L) and significant reductions in T:C (LP 8.03±0.80 to 6.67±0.83; UP 5.23±1.41 to 4.95±1.00). Finally, the UP group had a significantly higher Wilks coefficient following the competition compared to the LP group (LP 440.7±31.83 vs. UP 480.29±24.13). It appears that the higher volume loads undertaken by UP have a larger perturbation on resting stress hormones; however, this does not seem to negatively influence powerlifting performance.

Job interview training targeting nonverbal communication using an android robot for individuals with autism spectrum disorder.

Job interviews are significant barriers for individuals with autism spectrum disorder because these individuals lack good nonverbal communication skills. We developed a job interview training program using an android robot. The job interview training program using an android robot consists the following three stages: (1) tele-operating an android robot and conversing with others through the android robot, (2) a face-to-face mock job interview with the android robot, and (3) feedback based on the mock job interview and nonverbal communication exercises using the android robot. The participants were randomly assigned to the following two groups: one group received a combined intervention with "interview guidance by teachers and job interview training program using an android robot" (n = 13), and the other group received an intervention with interview guidance by teachers alone (n = 16). Before and after the intervention, the participants in both groups underwent a mock job interview with a human interviewer, who provided outcome measurements of nonverbal communication, self-confidence, and salivary cortisol. After the training sessions, the participants who received the combined interview guidance by teachers and the job interview training program using an android robot intervention displayed improved nonverbal communication skills and self-confidence and had significantly lower levels of salivary cortisol than the participants who only received interview guidance by teachers. The job interview training program using an android robot improved various measures of job interview skills in individuals with autism spectrum disorder.

Psychobiological response to an anger induction task in schizophrenia: The key role of anxiety

In this study an anger induction laboratory task was applied to men with schizophrenia, and resulted in significant changes in different psychophysiological parameters that were measured in a pre-post design. We observed a significantly greater self-reported anger mood and negative affection, lower self-reported positive affection, an increase in cardiovascular reactivity (with blood pressure in deeper affection compared to controls), higher salivary testosterone levels, lower salivary cortisol levels, and an increase in right ear items reported in dichotic listening. Furthermore, clinical risk factors related to anger in our patients were analyzed by Stepwise Regression analyses. Trait anger was significantly associated with a higher level of delusional pathology and impulsivity. Regarding the resulted state of anger as an output of the induction, the most relevant finding was that anxiety consistently and significantly predicted the increasing in anger feelings, and, remarkably, it predicted also the increasing in T levels and the cardiovascular reactivity of the patients.

Low salivary cortisol levels in patients with rheumatoid arthritis exposed to oral glucocorticoids: a cross-sectional study set within UK electronic health records

BackgroundGlucocorticoids (GCs) suppress endogenous cortisol levels which can lead to adrenal insufficiency (AI). The frequency of GC-induced AI remains unclear. In this cross-sectional study, low morning salivary cortisol (MSC) levels...

Effects of petting before a brief separation from the owner on dog behavior and physiology: A pilot study

Abstract Human physical contact is known to be effective in decreasing dogs' level of stress, assessed through endocrine, physiological, and behavioral parameters. Gentle touching has been found to be beneficial for dogs while experiencing or after having experienced a stressful event. The aim of the present study was to assess if dog behavior and physiology during a brief separation from the owner were modified by being petted before owner's departure. Ten dogs, not affected by separation-related problems, were tested twice while separated for 3 minutes from the owner: before separation, dogs once were petted for 1 minute and once were not petted. During each test, dog behavior was measured by continuous sampling and saliva collected 15 minutes after separation for cortisol determination. Findings show that, during both procedures, dogs spent a long time looking for the owner (median 84.5 and 87.5 seconds, respectively) and did not seem highly stressed by separation (low salivary cortisol levels and relatively low intensity and frequency of stress signals). When dogs were petted before separation, they displayed behaviors indicative of calmness for a longer period while waiting for the owner's return (Z = −1.955; P = 0.049), and their heart rate showed a marked decrease after the test (Z = −1.682; P = 0.073). This pilot study suggests that petting a dog before a brief separation from the owner may have a positive effect, making the dog calmer during the separation itself. Further studies are needed to analyze more in depth its effectiveness, especially in dogs affected by separation anxiety.

The impact of an exercise training intervention on cortisol levels and post-traumatic stress disorder in juveniles from an Ugandan refugee settlement: study protocol for a randomized control trial

BackgroundLatest research demonstrates a significant improvement in stress-related symptoms in psychological disorders as a result of exercise training (ET). Controlled clinical trials further validate the significance of ET by demonstrating lower salivary cortisol levels in patients with post-traumatic stress disorder (PTSD) after intervention. A significant change in cortisol and dehydroepiandrosterone (DHEA) levels can already be found after an 8–12-week ET program. The proposed study aims to investigate the impact of an 8-week ET on PTSD symptoms and changes in cortisol levels in a juvenile refugee sample from the Democratic Republic of the Congo (DRC) at an Ugandan refugee settlement. It is the first to implement an ET intervention in a resource-poor, post-conflict setting.Methods/designIn a randomized controlled trial, 198 adolescent participants aged 13–16 years from the DRC who, suffer from PTSD, will be investigated. The participants are based at the Nakivale refugee settlement, an official refugee camp in Uganda, Africa, which is among the largest in the world. The participants will be randomized into an Exercise Training (ET) group with a maximum heart rate (HRmax) of > 60%, an Alternative Intervention (AI) group with low-level exercises, and a Waiting-list Control (WC) group. After the 8-week interventional phase, changes in cortisol awakening response (CAR) and DHEA in the ET group that correspond to an improvement in PTSD symptoms are expected that remain at follow-up after 3 months.DiscussionTo date, there is no controlled and reliable longitudinal study examining the effects of an ET program on symptom severity in individuals with PTSD that can be explained with a harmonization of cortisol secretion. The presented study design introduces an intervention that can be implemented with little expenditure. It aims to provide a promising low-threshold and cost-effective treatment approach for the application in resource-poor settings.Trial registrationGerman Trials Register, ID: DRKS00014280. Registered prospectively on 15 March 2018.