Baseline Cortisol Concentrations Research Articles

Prey cortisol affects the usefulness of fecal glucocorticoid metabolite concentration as an indicator of stress in a carnivore

The noninvasive nature of sample collection makes analysis of fecal hormone concentrations useful for examining endocrine responses in free-living wild animals. Glucocorticoid hormones (i.e., cortisol and corticosterone) are frequently measured as an indicator of activation of the endocrine stress axis. However, many factors may influence glucocorticoid concentrations in feces, and the influence of prey glucocorticoids on concentrations in the feces of predators is rarely considered. We tested whether cortisol consumption influenced concentrations of glucocorticoid metabolites in feces of captive Arctic foxes (Vulpes lagopus (Linnaeus, 1758)) by adding cortisol (5 mg cortisol per kg fox body mass) to the foxes’ diet. Food supplemented with supraphysiological concentrations of cortisol increased fecal glucocorticoid metabolite concentrations of Arctic foxes by 97% in males and 51% in females, compared with controls. In addition, fecal metabolite concentrations in nontreatment samples were higher for females (22.2 ± 3.3 ng·g−1, mean ± SE) than males (13.3 ± 1.5 ng·g−1), suggesting female Arctic foxes may have higher baseline cortisol concentrations or females may be more sensitive to captivity or relocation. These results indicate that prey cortisol can influence measurement of glucocorticoid metabolites in carnivore feces and suggest caution may be needed when interpreting such measurements in wild carnivores.

Impact of an auditory stimulus on baseline cortisol concentrations in clinically normal dogs

Baseline cortisol concentrations are routinely used to screen dogs for hypoadrenocorticism (HOC); this diagnosis must then be confirmed with an ACTH stimulation test. A baseline cortisol concentration less than 55 nmol/L (2 μg/dL) is highly sensitive for HOC but lacks specificity, with a false positive rate >20%. Many dogs with nonadrenal disease are therefore subjected to unnecessary additional testing. It was hypothesized that exposure to an unpleasant auditory stimulus before sample collection would improve the specificity of baseline cortisol measurements in dogs with nonadrenal disease by triggering cortisol production. Twenty-eight healthy client-owned dogs were included in the study, with a median age of 4 yr (range 2–9 yr) and a median weight of 20 kg (range 10–27 kg). Dogs were ineligible for inclusion if they had received short- or long-acting glucocorticoids within the previous 30 and 90 d, respectively. Dogs were randomly assigned to group 1 (control; no noise; n = 7), group 2 (brief noise: n = 10), or group 3 (long noise: n = 11). Each dog and owner were directed to a secluded area for approximately 15 min. Group 1 sat in relative quiet, exposed only to the background sounds of a veterinary hospital. Group 2 were exposed to the sound of a wet-dry vacuum in an adjacent hallway during the first 3 min of this period. Group 3 were exposed to random bursts of wet-dry vacuum noise during this period. At the end of the test interval, each dog was escorted to an adjacent examination room for blood collection. Samples were processed within 15 min; serum was frozen at −80°C before measurement of cortisol concentrations. Median serum cortisol concentrations and the proportion of dogs with results <55 nmol/L were similar for the 3 groups. The study hypothesis that exposure to the noise of a wet-dry vacuum cleaner would consistently drive baseline serum cortisol concentrations above 55 nmol/L in dogs with apparently normal adrenal function was therefore rejected.

A Single, Post-ACTH Cortisol Measurement to Screen for Adrenal Insufficiency in the Hospitalized Patient.

Cosyntropin stimulation testing (CST) is used to screen patients for adrenal insufficiency (AI). Traditionally, CST includes baseline cortisol concentration, the administration of cosyntropin, and cortisol concentration at 30 and 60 minutes poststimulation. There is debate surrounding the utility of testing and cut-off points for concentrations at each time point. To determine if a single cortisol measurement at 30 or 60 minutes could replace the traditional approach. looked retrospectively at inpatients who underwent standard, high-dose CST (n = 702) and evaluated the number of patients who would screen positive for AI by using a single time point (30 or 60 minutes) compared with the traditional CST. A tertiary-care, academic medical center. Hospital inpatients present between January 2012 and September 2013. Of tests, 84.3% were normal, which was defined as at least 1 cortisol concentration of 18 mcg/dL or higher at any time after stimulation. The average 60-minute concentration was higher than the average 30-minute concentration (P < .001). A single 60-minute concentration is 100% concordant with the full CST in the intensive care unit (ICU) subgroup and 99.6% concordant in floor patients. A single 30-minute concentration is significantly less concordant, 91.9% and 86.9%, in the ICU and floor subgroups, respectively. Overall, a single 60-minute cortisol concentration to screen for AI was 99.7% concordant with the traditional CST, and the positive percent agreement was 98%. Fewer false-positive screens would occur with a single 60-minute cortisol concentration compared with a single 30-minute concentration (P < .001). High-dose CST screening may safely be interpreted with single 60-minute poststimulation cortisol serum concentrations.

Effects of Trilostane on urinary Catecholamines and their metabolites in dogs with Hypercortisolism

BackgroundGlucocorticoids influence the synthesis and metabolism of catecholamines (epinephrine and norepinephrine) and metanephrines (metanephrine and normetanephrine). The aim of this study was to measure urinary catecholamines and metanephrines in dogs with hypercortisolism before and during trilostane therapy.Urine samples were collected during initial work up and during therapy with trilostane in 14 dogs with hypercortisolism and in 25 healthy dogs. Epinephrine, norepinephrine, metanephrine and normetanephrine were measured using high-pressure liquid chromatography and expressed as ratios to urinary creatinine concentration.ResultsUntreated dogs with hypercortisolism had significantly higher epinephrine, norepinephrine, and normetanephrine:creatinine ratios compared to healthy dogs. During trilostane therapy, urinary catecholamines and their metabolites did not decrease significantly. However, dogs with low post-ACTH cortisol concentrations during trilostane therapy had less increased epinephrine, norepinephrine and normetanephrine:creatinine ratios compared to healthy dogs. There was no correlation of urinary catecholamines and their metabolites with baseline or post-ACTH cortisol or endogenous ACTH concentrations during trilostane therapy.ConclusionInfluences between steroid hormones and catecholamines seem to occur, as dogs with hypercortisolism have significantly higher urinary epinephrine, norepinephrine, and normetanephrine:creatinine ratios. Once-daily trilostane therapy does not lead to a significant decrease in catecholamines and their metabolites. Trilostane-treated dogs still have increased urinary epinephrine, norepinephrine and normetanephrine:creatinine ratios during trilostane therapy.

Effects of maternal cortisol treatment on offspring size, responses to stress, and anxiety-related behavior in wild largemouth bass (Micropterus salmoides)

Cortisol, the main glucocorticoid stress hormone in teleost fish, is of interest as a mediator of maternal stress on offspring characteristics because it plays an organizational role during early development. The present study tested the hypothesis that maternal exposure to cortisol treatment prior to spawn affects offspring phenotype using wild largemouth bass (Micropterus salmoides). Baseline and stress-induced cortisol concentrations, body size (i.e. length and mass), and behavior (i.e. anxiety, exploration, boldness, and aggression) were assessed at different offspring life-stages and compared between offspring of control and cortisol-treated females. Cortisol administration did not affect spawning success or timing, nor were whole-body cortisol concentrations different between embryos from cortisol-treated and control females. However, maternal cortisol treatment had significant effects on offspring stress responsiveness, mass, and behavior. Compared to offspring of control females, offspring of cortisol-treated females exhibited larger mass right after hatch, and young-of-the-year mounted an attenuated cortisol response to an acute stressor, and exhibited less thigmotaxic anxiety, exploratory behavior, boldness and aggression. Thus, offspring phenotype was affected by elevated maternal cortisol levels despite the absence of a significant increase in embryo cortisol concentrations, suggesting that a mechanism other than the direct deposition of cortisol into eggs mediates effects on offspring. The results of the present raise questions about the mechanisms through which maternal stress influences offspring behavior and physiology, as well as the impacts of such phenotypic changes on offspring fitness.

An exploratory study of competition scores and salivary cortisol concentrations in Warmblood horses

The main objective of this explorative study was to describe the relationship between competition scores and salivary cortisol concentrations in young horses during dressage and showjumping competitions. The study also investigated whether the diurnal rhythm of salivary cortisol concentrations was affected by competition over consecutive days compared with the home environment. Saliva samples were collected from 126 dressage horses and showjumpers in their home environment and at 3 different events. The relationship between scores given by judges at the competition and cortisol concentrations at the event was assessed. The results demonstrated that competition scores correlated positively to baseline cortisol concentrations at one of 3 events (r = 0.53, P < 0.001). Salivary cortisol concentrations followed a diurnal rhythm with the highest concentrations measured in the morning and the lowest in the evening, both at home and in the competition environment (P < 0.05). Salivary cortisol concentrations were greater during the competitions than at home (P < 0.05) except at one event where showjumpers did not increase between home and competition. Dressage horses had the highest baseline cortisol concentrations at competition, and exercise caused cortisol concentrations to increase in both showjumpers and dressage horses (P < 0.001). In conclusion, the diurnal rhythm in salivary cortisol concentrations was maintained in the novel environment. Dressage horses demonstrated greater baseline cortisol concentrations at competition than showjumpers, suggesting that they may perceive the novel environment as more stressful. Furthermore, there was no consistent relationship between baseline salivary cortisol concentrations and competition scores across the events.

Adrenal cortex reactivity in dairy cows differs between lactational stages and between different feeding levels

Changes in ACTH challenge test characteristics in dairy cows changing their physiological status at different lactational stages and different feeding levels were not investigated in terms of repeatability yet. In 23 multiparous Holstein cows (10 cows fed a sole fresh herbage diet without concentrate, 13 cows fed with concentrate), three ACTH challenge tests were performed: once during pregnancy shortly prior to drying off (T1), and in week 3 (T2) and 8 (T3) after parturition. Test characteristics were correlated to performance and metabolic parameters: DMI, BW, energy balance (EB), plasma concentrations of free fatty acids (NEFA) and beta-hydroxybutyrate (BHB). Basal plasma cortisol concentrations were higher at T1 compared with T2 and T3 (p<.05). The adrenal cortex sensitivity (expressed as total AUC (AUCt ) of cortisol response after ACTH application) was lowest at T2 compared with T1 and T3 (p<.05). Ranking of the individual animals' responses was not repeatable between time points of the ACTH tests. Enhancing the energy deficiency during early lactation by omission of concentrate did not affect baseline cortisol concentrations in plasma, but decreased peak height at T2 (p<.05). Baseline plasma cortisol concentrations were positively correlated with cortisol peak values after ACTH application, previous lactation performance, milk yield and BW (p<.05). The AUCt was positively correlated with baseline cortisol concentrations, EB and DMI. Cortisol release after ACTH injection was lower in animals with high plasma concentrations of NEFA, BHB and with higher contents of fat and free fatty acids in milk (p<.05). Cortisol peak height after ACTH administration was higher in cows with a more positive EB, higher DMI and lower plasma concentrations of NEFA and BHB. In summary, cortisol responses to ACTH challenges in this study were not repeatable in dairy cows changing their physiological status.

Extended low-dose dexamethasone suppression test for diagnosis of atypical Cushing's syndrome in dogs

The purpose of this study was to evaluate extension of the low-dose dexamethasone suppression (LDDS) test from 8 h to 12 h to detect possible hypercortisolemia associated with atypical hyperadrenocorticism (AHAC). Twelve client-owned dogs were enrolled in the study: 6 healthy dogs (group 1) and 6 dogs with suspected AHAC (group 2). Baseline EDTA plasma samples were collected for endogenous ACTH determination using an immunoradiometric assay. Serum samples were collected before and at 4, 8, 10, and 12 h post-administration of 0.01 mg/kg dexamethasone IV for cortisol concentration determination via chemiluminescent assay. Mean endogenous ACTH concentration did not differ between groups (group 1: 22.4 pg/mL, group 2: 20.0 pg/mL; P > 0.2). Mean baseline cortisol concentration also did not differ significantly between groups (group 1: 3.03 μg/dL, group 2: 4.95 μg/dL; P > 0.2) nor was there any difference in mean cortisol concentration between the groups at any other time point (P > 0.2). The cortisol concentration from 1 dog in group 2 suppressed to 0.7 μg/dL at 8 h but increased to 1.5 μg/dL at 10 h and 3.7 μg/dL at 12 h post-dexamethasone. Based on results of this study, use of an extended LDDS test could not differentiate between healthy dogs and dogs with AHAC. Diagnosis of AHAC should continue to be based on prior established criteria until new testing has been identified.

Analysis of person-situation interactions in educational settings via cross-classified multilevel longitudinal modeling: illustrated with the example of students’ stress experience

The investigation of learning processes by assessing students’ experience along with objective characteristics within a classroom context has a long tradition in empirical learning process research (e.g. Sembill, 1984 et passim; Wild & Krapp, 1996). However, most of the existing studies confine themselves to psychological variables that seem to be too narrowly considered, as there is theoretical and empirical evidence proving the involvement of somatic and psychological processes in learning and in stress reactions. Furthermore there is a lack of studies that investigate situation-related experience (states) as an outcome of interactions between relatively stable characteristics (traits) and continuously changing “objective” context conditions. Against this background, we will present an approach for cross-classified multilevel longitudinal modelling of person-situation interactions in naturalistic educational settings. We illustrated our model with the example of students’ stress experience referring to empirical data that we measured within a multidisciplinary research project (pedagogy, psychology, adolescent medicine). 53 students at a public German vocational school were investigated during 9 lessons. There are up to 38 state measurements per person, resulting in 2,014 measurements in total. Taking into account that states are nested within persons and within situations we applied a cross-classified multilevel model to analyse effects on students’ stress experience. The analysis shows significant person-situation interactions between academic self-concept and classroom demands and between baseline cortisol concentration and classroom demands: the relation between classroom demands and stress experience depends on relatively stable person-related characteristics. A deeper knowledge about the complex interrelations between traits, states, and continuously changing context conditions seems to be essential for a more holistic understanding of learning at school and for the identification of crucial aspects for an evidence-based design and implementation of teaching and learning arrangements.

Evaluation of baseline cortisol concentration to monitor efficacy of twice-daily administration of trilostane to dogs with pituitary-dependent hyperadrenocorticism: 22 cases (2008-2012).

To evaluate use of cortisol concentration prior to ACTH stimulation (baseline) to monitor efficacy of twice-daily administration of trilostane to dogs with pituitary-dependent hyperadrenocorticism (PDH). Retrospective case series. 22 dogs with PDH. The database of a veterinary hospital was searched to identify dogs with PDH that were treated with the FDA-approved veterinary formulation of trilostane twice daily between January 1, 2008, and December 31, 2012. For each dog, signalment and details regarding each hospital visit including comorbidities, electrolyte concentrations, and clinical signs were extracted from the record. For each ACTH stimulation test performed, the respective correlations between baseline cortisol concentration and the cortisol concentration after ACTH stimulation (ACTH-stimulated cortisol concentration) and resultant decision regarding trilostane dose adjustment were determined. Excessive suppression of cortisol production was defined as an ACTH-stimulated cortisol concentration < 2.0 μg/dL. The ability of various baseline cortisol concentrations to predict whether a dog had excessive suppression of cortisol production was determined. 109 ACTH stimulation tests were performed for the 22 dogs. A baseline cortisol concentration > 3.2 μg/dL predicted that ACTH-stimulated cortisol concentration would be ≥ 2.0 μg/dL with 100% certainty; however, 14 of 64 tests with a baseline cortisol concentration > 3.2 μg/dL had an ACTH-stimulated cortisol concentration ≤ 3.2 μg/dL, which was suggestive of inadequate adrenocortical cortisol reserves. Results indicated that baseline cortisol concentration should not be used as the sole monitoring tool for management of dogs with PDH treated with trilostane twice daily.

Magnesium, C-reactive protein, and cortisol in drug-naïve patients with short illness-duration, first episode major depressive disorder: possible immunomodulatory role for magnesium.

Plasma magnesium concentration alterations, hypercortisolaemia, and systemic inflammation are observed in major depressive disorder (MDD). This exploratory study examined whether, and to what extent, plasma magnesium is related to C-reactive protein (CRP) levels and cortisolaemia in MDD. The concentrations of plasma magnesium, salivary CRP, and baseline plasma cortisol were studied in 20, treatment-naïve MDD patients with short-illness-duration, first affective episodes and 20 matched controls. Depressed patients showed a basal score higher than 20 on the Hamilton Rating Scale for Depression (HAMD-17). Significantly higher magnesium (p=0.016) and baseline cortisol (p=0.01) concentrations were observed in MDD as compared to controls. No significant difference in CRP concentrations between the MDD and control groups was observed. A significant negative correlation was seen between magnesium and CRP in MDD (p<0.01), whereas no correlation was found in controls. A significant positive correlation was found between cortisol and CRP, both in MDD subjects (p=0.008) and controls (p=0.004). No significant correlations were observed between magnesium and cortisol levels. The study supports data for hypercortisolaemia in MDD, but provides no evidence of primary hypomagnesaemia or elevated CRP levels in drug-naïve MDD patients with short-illness-duration. The study supports the hypothesis linking hypercortisolaemia to systemic inflammation, with hypermagnesaemia exerting an immunomodulatory action at early stages of the disease.

Preclinical laboratory assessments of predictors of social rank in female cynomolgus monkeys.

Physiological and behavioral differences between dominant and subordinate monkeys have been useful in preclinical models investigating numerous disease states. In captivity, it has been inferred that subordinate monkeys live in a context of chronic social stress and may be at risk for a variety of dysfunctions; however, the factors that influence eventual rank are not entirely known. The goal of the present study was to first evaluate several phenotypic characteristics as potential trait markers for eventual social rank and then to determine the consequences of social hierarchy on these measures (i.e., state markers). Baseline estradiol, progesterone, cortisol and testosterone concentrations were obtained from 16 pair-housed female cynomolgus monkeys before and after introduction into new social groups (n = 4/group). Furthermore, effects of the initial week of social rank establishment on outcome measures of cognitive performance and homecage activity were examined. Baseline body weight and mean serum estradiol concentrations were the only statistically significant predictors of eventual rank, with future subordinate monkeys weighing less and having higher estradiol concentrations. During initial hierarchy establishment, future subordinate monkeys had increased morning and afternoon cortisol concentrations, increased locomotor activity and impaired cognitive performance on a working memory task. After 3 months of social housing, subordinate monkeys had blunted circulating estradiol and progesterone concentrations. These findings demonstrate differential effects on gonadal hormones and cortisol as a function of social context in normally cycling female monkeys. Furthermore, disruptions in cognitive performance were associated with subordinate status, suggesting strong face validity of this model to the study of factors related to the etiology and treatment of human diseases associated with chronic stress. Am. J. Primatol. 78:402-417, 2016. © 2015 Wiley Periodicals, Inc.

Seasonal variation in baseline and maximum whole-body glucocorticoid concentrations in a small-bodied stream fish independent of habitat quality

Alterations to natural habitats are becoming more common due to changes in anthropogenic land use. As such, there is increasing interest in determining how wild animals adapt and respond to environmental stressors. The glucocorticoid (GC) stress response enables animals to react appropriately to environmental challenges but can be affected by many factors, two of which are habitat quality and time of year (i.e., season). This study tested whether baseline and maximum (stress-induced) whole-body cortisol concentrations varied in relation to habitat quality and season using wild central mudminnows (Umbra limi) collected from two connected streams differing in habitat quality in each of four seasons. Overall, baseline and maximum cortisol levels did not differ significantly between the two systems but there was evidence of a seasonal effect. Baseline cortisol levels in the fall and summer were significantly (P<0.01) lower than those in winter and spring and maximum cortisol levels in the summer were significantly lower (P<0.01) than those in the spring. Inconsistent with the prevailing paradigm, our results indicate that habitat quality does not always influence baseline GCs or the stress response. In contrast, baseline and maximum GCs in this species do vary seasonally. As such, seasonality should be considered in the interpretation of stress response data especially when using small-bodied stream fish as biological indicators.

Effects of Therapeutic Riding on Measures of Stress in Horses

The popularity of therapeutic riding is growing rapidly. With greater numbers of horses used in this field, it is becoming increasingly important to understand how this work impacts horse quality of life. Salivary cortisol concentrations and behavior scores are two measures of stress in horses, and the goal of this study was to test the hypothesis that horses used in therapeutic riding exercises have greater increases in cortisol concentrations during therapeutic riding, when compared to a traditional hunt seat lesson program or at rest. Salivary cortisol concentrations were measured in six adult horses on 3 days per week for a total of 6 weeks. Horses served as their own controls, and salivary cortisol concentrations were measured during therapeutic riding, traditional riding, and at rest, with samples collected at 0, 30, and 60 minutes. Delta cortisol concentrations were calculated by subtracting baseline cortisol concentrations from values obtained at 30 or 60 minutes. Delta salivary cortisol values were compared among different types of activity by the nonparametric Wilcoxon matched-pairs signed-rank test. No significant differences in delta cortisol values were detected between riding conditions. Delta salivary cortisol values at 30 minutes were 0.147, 0.0762, and −0.032 μg/dL for rest, traditional riding, and therapeutic riding conditions, respectively, and delta values at 60 minutes were −0.0177, −0.002, and −0.031 μg/dL, respectively. Behavior scores did not differ significantly between different riding conditions. Our hypothesis was not supported, and we conclude that therapeutic riding was not associated with increased stress in horses in this sample.

Cortisol secretion in response to metabolic and inflammatory challenges in dairy cows.

Cortisol in dairy cows is released in an episodic manner underlying a circadian rhythm. The involvement of cortisol in numerous adaptive processes to cope with adverse conditions such as pain and inflammation is well characterized. Recent studies described contradictory effects of nutrition and metabolism on the secretory pattern of cortisol. However, up to now, the direct effects of single metabolites during various metabolic conditions without the profound endocrine changes around parturition on the glucocorticoid secretion in dairy cows have not been described. The objective of this study was to investigate the effects of long-term (56-h) manipulated metabolic states, that is, manipulated plasma concentrations of glucose and β-hydroxybutyrate (BHBA), on the release of cortisol in midlactation dairy cows. Besides the concentration of cortisol at defined time points, its pulsatile secretory pattern was studied in combination with an acute immune challenge through an intramammary lipopolysaccharide (LPS) challenge. Twenty-five midlactation dairy cows were randomly assigned to 1 of 4 treatments (hyperinsulinemic hypoglycemic clamp [HypoG], hyperinsulinemic–euglycemic clamp [EuG], continuous infusion of BHBA [HyperB], or infusion of saline solution for the control group [Control). Different metabolic states induced by infusion treatments affected the characteristics of cortisol secretion (elevation of baseline [the HypoG and HyperB treatments] and decreased peak length [the HypoG treatment]; P < 0.05), whereas amplitude, peak interval, height, peak area, area under the curve (AUC) above the baseline cortisol concentration (AUCb), and the total AUC (AUCt) were not different between infusion treatments. The induced inflammatory response due to the intramammary LPS challenge at simultaneously maintained infusion treatments diminished the pulsatile nature of cortisol release, whereas AUCb (and AUCt, respectively) was lowest for the HypoG treatment compared with the HyperB and Control treatments (P < 0.05). This study indicates that single metabolites (glucose and BHBA) and their availability or turnover (in case of glucose) have a different impact on the regulation of cortisol secretion resulting in changes of its pulsatile release. Furthermore, cortisol release during intramammary inflammation was found to be greater in the HyperB, EuG, and Control treatments compared with the HypoG treatment (P < 0.05). This finding emphasizes the regulatory role of the current metabolic status on the cortisol release during inflammation.

Temporal concentrations of cortisol and LH in virgin ewes acutely exposed to rams during the transition into the breeding season

The objectives of this study were to determine if exposing seasonally anovular ewes to rams would alter patterns of cortisol concentrations, and if these changes are associated with changes in characteristics of LH concentrations. Seasonally anestrous ewes were assigned to be exposed to rams (RE; n=11) or wethers (NE; n=12). Blood samples were collected at 15-min intervals beginning 120min before introduction of males (time=0min), and continued for 360min after male exposure. Characteristics of cortisol and LH concentrations included: mean and baseline concentrations, pulse amplitude, duration, frequency, and time to first pulse. Mean and baseline cortisol concentrations, and cortisol pulse amplitude, frequency, and time to first pulse after male exposure did not differ between RE and NE ewes. Cortisol pulse duration was longer (P<0.05) in RE ewes than in NE ewes. Mean LH and LH pulse amplitude, duration, and time to first pulse after male exposure did not differ between RE and NE ewes. Baseline LH concentrations and LH pulse frequency were greater (P<0.05) in RE than in NE ewes. In RE ewes, but not NE ewes, LH pulse frequency tended to increase (P=0.06) as pulse frequency of cortisol decreased. In conclusion, exposing ewes to mature rams during the transition into the breeding season increased LH pulse frequency which hastened ovulatory activity. However, the results do not support the hypothesis that changes in cortisol concentrations plays a significant role in the ‘ram effect’.

Influence of Handling Method on Adrenal Activity in Zoo African and Asian Elephants

As a first step towards investigating the effect of management choice – free contact (FC) or protected contact (PC) – on zoo elephant well-being, this study evaluated serum cortisol concentrations in weekly samples collected over a 2-year period from 112 female elephants (58 African, 54 Asian) managed in either FC (n=58) or PC (n=54) management systems at 48 facilities. Results showed there were no differences in overall or baseline mean concentrations of serum cortisol between the two management systems. A GLM analysis exploring the response of individual baseline cortisol concentration to management (FC vs PC), facility, species, and the interaction of management and facility revealed that the only parameter with significant explanatory power was the facility where the elephants were housed. Thus, it may be more important to evaluate specific facility effects on adrenal activity, such as enclosure conditions, enrichment opportunities, or social interactions, rather than handling technique. Although many zoos are moving to a PC management approach, particularly within the American Zoo and Aquarium Association, from a welfare standpoint there is probably not a one-size-fits-all management strategy that is ideal. Rather, it may be necessary to consider individual elephant coping styles and social needs on a case by case basis before deciding whether FC or PC is most appropriate for management, especially when considering how to address welfare concerns.

Plasma levels of tumor necrosis factor-α in adolescent idiopathic scoliosis patients serve as a predictor for the incidence of early postoperative cognitive dysfunction following orthopedic surgery.

The aim of the present study was to evaluate whether the levels of the plasma biomarkers, cortisol, interleukin (IL)-1β, IL-6, IL-10 and tumor necrosis factor (TNF)-α, change in adolescent idiopathic scoliosis patients with postoperative cognitive dysfunction (POCD); thus, may serve as predictive factors for POCD. In total, 75 adolescent scoliosis patients, aged between 11 and 18 years and categorized as American Society of Anesthesiologists classification I or II, were scheduled for orthopedic surgery with general anesthesia. Blood samples were collected on the day of admission and at day 2 following surgery. The plasma levels of IL-1β, IL-6, IL-10 and TNF-α were measured using an enzyme-linked immunosorbent assay, while the concentrations of cortisol were determined using a radioimmunoassay. Cognitive function was assessed one day prior to and at day 7 following the surgery in a quiet room with the guidance of a Chinese version protocol. In total, 66 patients completed the sample collection and neurocognitive tests. According to the criteria for the diagnosis of POCD, 19 patients (28.8%) developed POCD within seven days of surgery. No statistically significant differences were observed in the baseline concentrations of cortisol, TNF-α, IL-1β, IL-10 or IL-6 between the POCD and non-POCD groups. However, the baseline plasma level of TNF-α on day 2 in the POCD group was found to be higher compared with the non-POCD group. In addition, at day 2 after surgery, the concentration of cortisol in the non-POCD group was higher compared with the POCD group. Therefore, the plasma level of TNF-α in adolescent idiopathic scoliosis patients at day 2 following orthopedic surgery may be a predictor for the incidence of early POCD.

Adrenal responses to a low-dose short synacthen test in children with asthma.

Corticosteroids are known to cause adrenal suppression. The aim of this study was to assess clinical factors affecting responses to a low dose short synacthen test (LDSST) in asthmatic children using corticosteroids. Patients were recruited from secondary care paediatric asthma populations within the UK. Asthmatic children (5-18 years), receiving corticosteroids, underwent a LDSST (n = 525). Demographics and corticosteroid doses were tested for association with baseline and peak (stimulated) cortisol concentrations. Baseline cortisol was significantly associated with age (log baseline increased 0·04 nm per year of age, P < 0·0001), but not with gender or corticosteroid dose. Peak cortisol was significantly associated with total corticosteroid cumulative dose (decreased 0·73 nm per 200 mcg/day, P < 0·001) but not with age, gender inhaled/intranasal corticosteroid cumulative dose or number of courses of rescue corticosteroids. Biochemically impaired response (peak cortisol ≤500 nm) occurred in 37·0% (161/435) overall, including children using GINA low (200-500 mcg/day beclomethasone-CFC equivalent 32%, n = 60), medium (501-1000 mcg/day (33%, n = 57) and high (>1000 mcg/day 40%, n = 13) doses of inhaled corticosteroid (ICS) similarly, and 36·6% of those using fluticasone ICS ≥500 mcg/day (71/194). Impaired response was more frequent in patients on regular oral corticosteroids (66%, n = 27, P < 0·001). Children with asthma can develop biochemical adrenal suppression at similar frequencies for all ICS preparations and doses. The clinical consequence of biochemical suppression needs further study.

Prognostic significance of hypothalamic-pituitary-adrenal axis hormones in early sepsis: a study performed in the emergency department.

The response of the hypothalamic-pituitary-adrenal (HPA) axis to the sustained stress of sepsis has been the focus of study in recent years because the early phase of sepsis is known to be dominated by major alterations in the HPA axis. This prospective observational study aimed at assessing the predictive values of copeptin and HPA hormones in determining sepsis progression and mortality in the emergency department (ED). Serum arginine vasopressin (AVP) and copeptin concentrations were measured upon ED admission. Baseline levels of total and free cortisol and adrenocorticotrophic hormone (ACTH) were measured within 24 h of ED admission. Mortality in Emergency Department Sepsis (MEDS) score was calculated at enrollment. Our findings demonstrated that serum copeptin, baseline total cortisol, baseline free cortisol and baseline ACTH concentrations gradually increased, based upon the increasing severity of the disease (p < 0.001). Multivariate logistic regression analysis showed that copeptin and total cortisol baseline concentrations were independent predictors of septic shock (odds ratio = 1.034 and 1.355, respectively) and 28-day mortality (odds ratio = 1.039 and 1.499, respectively). The areas under the receiver operating characteristic curve (AUC) for copeptin level in prediction of septic shock was 0.856 and 28-day mortality was 0.826. Importantly, AUC analysis of the combination of copeptin, total cortisol baseline, MEDS score, and procalcitonin level resulted in a more significant prognostic ability than analysis of each parameter alone (p < 0.001). Increased copeptin and HPA hormones baseline levels may provide crucial information for risk stratification in a variety of septic states in the ED. Furthermore, measurements of copeptin level and serum baseline cortisol concentration are promising independent prognostic markers for mortality in patients with severe sepsis or septic shock.