Salivary Cortisol Awakening Response as a Predictor for Depression Severity in Adult Patients with a Major Depressive Episode Performing a Daily Exercise Program

<b><i>Introduction:</i></b> The hypothalamic-pituitary-adrenal axis function in depression has been the subject of considerable interest, and its function has been tested with a variety of methods. We investigated associations between saliva cortisol at awakening and the 24-h urine cortisol output, both measured at study baseline, with endpoint depression scores. <b><i>Methods:</i></b> Patients were admitted to a psychiatric inpatient ward with a major depressive episode and were started on fixed duloxetine treatment. They delivered saliva samples at awakening and 15, 30, and 60 min post-awakening and sampled urine for 24 h. Subsequently, they started a daily exercise program maintained for a 9-week period. Clinician-rated depression severity was blindly assessed with the Hamilton Depression Rating 6-item subscale (HAM-D₆). The cortisol awakening response was quantified by the area under the curve with respect to the ground (AUC_G) and with respect to the rise (AUC_I) using saliva cortisol levels in the 1-h period after awakening. Analysis of expected associations between depression severity, AUC_G, AUC_I, exercise, and 24-h cortisol output was performed in a general linear model. <b><i>Results:</i></b> In all, 35 participants delivered saliva or 24-h urine samples. The mean age was 49.0 years (SD = 11.0) with 48.6% females with a mean baseline HAM-D₆ score of 12.2 (SD = 2.3). In a statistical model investigating the association between HAM-D₆ at week 9 as a dependent variable and AUC_I, concurrent HAM-D₆, gender, smoking, and exercise volume as covariates, we found a significant effect of AUC_I, concurrent HAM-D₆, and exercise. The following statistics were found: AUC_I (regression coefficient 0.008; <i>F</i> value = 9.1; <i>p</i> = 0.007), concurrent HAM-D₆ (regression coefficient 0.70; <i>F</i> value = 8.0; <i>p</i> = 0.01), and exercise (regression coefficient −0.005; <i>F</i> value = 5.7; <i>p</i> = 0.03). The model had an <i>R</i>² of 0.43. The association between HAM-D₆ endpoint scores and the AUC_I showed that higher AUC_I values predicted higher HAM-D₆ endpoint values. The association between HAM-D₆ endpoint scores and the exercise level showed that a high exercise level was associated with lower HAM-D₆ endpoint values. <b><i>Conclusion:</i></b> The results thus showed that high AUC_I values predicted less improvement of depression and high exercise levels predicted more improvement of depression. These findings need to be confirmed in larger samples to test if more covariates can improve prediction of depression severity.

Saliva and Blood Cortisol Measurement in Bottlenose Dolphins (Tursiops truncatus): Methodology, Application, and Limitations

A central task of zoos and aquaria is the frequent and accurate assessment of their animals’ welfare. Recently, important steps have been made, such as the introduction of animal welfare evaluation tools and welfare decision trees. To determine animal welfare, it is not only important to collect life history data, such as longevity and reproductive success, but also for experienced observers or caretakers to conduct behavioral observations on a regular basis to assess animals’ emotional state. To physiologically validate welfare observations, glucocorticoid levels are usually assessed, as they are a common indicator of stress. While, for many animals, these levels can be easily determined via fecal or hair samples, for cetaceans, the levels are usually determined via blood samples. As blood samples cannot be taken very frequently and the process may cause stress to the animals (if the samples are not taken following medical training), other techniques, such as the measurement of health biomarkers (especially cortisol, which can be measured in saliva), have become the focus of cetacean stress research. However, there are two problems associated with saliva measurements in cetaceans: saliva might either be diluted with pool water or be contaminated by fodder fish, as frozen fish usually contains high levels of cortisol. In our study, we investigated how saliva cortisol levels are connected to blood cortisol levels and how saliva cortisol can be influenced by fodder fish. We examined saliva and blood samples in eleven bottlenose dolphins (Tursiops truncatus) kept in an outdoor and indoor facility in Germany. Furthermore, we assessed the cortisol levels of different kinds of fodder fish. Our data show that, although saliva cortisol values are elevated under stress and arousal, they seem not to be correlated with blood cortisol values. We also show that, after feeding, saliva cortisol values are increased up to 100-fold. Our results suggest that saliva cortisol measurements in dolphins have to be conducted and considered with care, as they can easily be contaminated. Moreover, it is important to use the right laboratory method in order to specifically detect cortisol; in our study, we conducted reliable tests, using LC-MS/MS.

Effects of virtual reality v. biophilic environments on pain and distress in oncology patients: a case-crossover pilot study

This pilot study aimed to determine if a biophilic Green Therapy or Virtual Reality environment can decrease an oncology patient’s pain and distress while receiving chemotherapy. A case-crossover pilot study was conducted in a comprehensive cancer infusion center. 33 participants with breast, gynecologic, gastrointestinal, pancreatic and prostate cancers were all included in three rooms in a random order at different cycles: control room, Green Therapy room, and Virtual Reality room to receive chemotherapy, respectively. Participants’ pain, distress, heart rate, blood pressure, and saliva cortisol were measured before and after infusion in each room. No statistical significance differences were shown in the changes of heart rate, systolic, or diastolic blood pressure, saliva cortisol, pain, or distress before and after infusion between the control, Green Therapy, and Virtual Reality rooms. However, more patients reported the experience as “fun” and “enjoyable” when they were in Green Therapy or Virtual reality room as compared to in the control room. Additionally, since participating in the study, 14 patients reported spending at least 30 min or more outside in nature. In this study, we found that patients’ heart rate, blood pressure, and self-reported distress levels were reduced after each biophilic intervention although results are not statistically significant. The study also suggested that biophilic interventions are safe and feasible and may complement the standard of care for oncology patients.

Psychophysiological Predictors of Soldier Performance in Tunnel Warfare: A Field Study on the Correlates of Optimal Performance in a Simulation of Subterranean Combat

ABSTRACT Tunnel operations produce unique psychophysiological activation that is correlated with cognitive impairment and lower performance. This study introduces a new concept: subterranean operational potential (SOP) and assesses its psychophysiological correlates for performance prediction in underground spaces. 138 soldiers of elite infantry battalions, with/without previous experience, who participated in a simulation of tunnel warfare. Physical, psychological, cognitive style, and performance measures were collected. SOP has three sub-components: performance, leadership, and orientation. Leadership and performance both were negatively correlated with perceived stress. Claustrophobia was negatively correlated with leadership. The cognitive style was positively correlated with performance. Saliva cortisol levels were significantly higher before the simulation. Inexperienced and experienced differed in the change in before-after saliva cortisol levels.

The Effect of A Whey-Protein and Galacto-Oligosaccharides Based Product on Parameters of Sleep Quality, Stress, and Gut Microbiota in Apparently Healthy Adults with Moderate Sleep Disturbances: A Randomized Controlled Cross-Over Study

People experiencing sleep problems may benefit from nutrients supporting serotonin metabolism and stress reduction. We studied the effect of a dairy-based product (DP) containing protein, galacto-oligosaccharides, vitamins and minerals, on sleep quality, stress, and gut-microbiota. In a cross-over RCT (three weeks intervention; three weeks washout), adults (n = 70; 30–50 y) with sleep disturbances (Pittsburgh Sleep Quality Index (PSQI) ≥ 9) consumed products 1 h before bed-time. Sleep quality (PSQI) was measured weekly, stress at base- and end-line (Depression Anxiety Stress Scale and saliva cortisol). Fecal samples were collected in the 1st intervention period only. Compared to placebo (skimmed milk), PSQI was only lower at day 14 in the 2nd intervention period in intention-to-treat (ITT) (p = 0.017; n = 69) and per-protocol (PP) (p = 0.038; n = 64) analyses. Post-hoc analysis (modified-PP: n=47, with baseline PSQI ≥ 9, and endline day 14), however, showed a decrease in PSQI (−1.60 ± 2.53; p = 0.034). Early morning saliva cortisol decreased versus placebo (p = 0.045). Relative abundance of Bifidobacterium increased (p = 0.02). Redundancy analysis showed an inverse relationship between baseline microbiota composition and baseline PSQI (p = 0.046). Thus, although DP did not improve sleep quality in ITT and PP populations, it did in the modPP. DP reduced salivary cortisol and stimulated Bifidobacterium, which possibly is important for sleep improvement.