Variation Of Cortisol Research Articles

Evaluation of Adrenal Reserve in Children with Acute Lymphocytic Leukemia Treated with Prednisone or Dexamethasone

Background/Aims: The purpose of this study was to compare adrenal gland reserve in acute lymphocytic leukemia (ALL) patients 8 weeks after treatment with either prednisone (PRED) or dexamethasone (DEX) during the induction phase of therapy. Methods: A double-blind comparative study of patients treated with PRED and DEX was performed. Sixteen patients received PRED (40 mg/m²/day) and 13 patients received DEX (6 mg/m²/day), both for 28 days. A low-dose adrenocorticotropic hormone test (1.0 µg/m², IV) was performed before and weekly for 8 weeks after abrupt cessation of glucocorticoid therapy. Sixteen children without ALL were used as controls to determine the cutoff peak cortisol level (14.2 µg/dl). Results: Both groups (PRED and DEX) displayed similar mean peak cortisol levels before treatment and during the 8 weeks of evaluation (p = 0.652). No relationship was observed between the incidence of infection/stress and peak cortisol level within each group, nor was there a difference in the frequency of infection/stress between groups (p = 0.359). Although the patients presented variations in peak cortisol during the study period, no signs or symptoms of adrenal insufficiency were observed. Conclusion: Patients who received PRED or DEX for 4 weeks showed similar adrenal reserves and infection rates for 8 weeks after abruptly stopping glucocorticoid therapy, suggesting that DEX, which is a better antileukemic drug than PRED, has similar adrenal suppression and recovery rates.

The Influence of Intensive Physical Training on Salivary Adipokine Levels in Elite Rhythmic Gymnasts

Exercise challenges homeostasis and establishes a new dynamic equilibrium. Elite Rhythmic Gymnasts (RG's) begin exercise at an early age, undergo physical and psychological stress, and adopt negative energy balance to retain a lean physique. The aim of the present study was to evaluate the effect of negative energy balance, acute and chronic exercise on salivary adiponectin, resistin and visfatin levels and their interaction with salivary cortisol, and insulin levels in elite RG's. This study is unique in character, as all variables were assessed on the field of competition. The study included 51 elite RG's participating in "Kalamata 2010 World Cup" in Kalamata, Greece on April 2010. Twenty-seven healthy age-matched girls were used as controls. Anthropometric values were assessed; baseline and post exercise salivary cortisol, insulin, adiponectin, resistin, and visfatin levels were measured. Comparisons regarding hormonal features between RG's and controls were adjusted for BMI and body fat percentage. Salivary adiponectin levels were higher (p<0.05) and visfatin lower (p=0.094) in RG's compared with controls, while no significant changes were observed regarding salivary cortisol, insulin, and resistin levels. In elite RG's acute intensive anaerobic exercise led to increased salivary insulin levels (p<0.001), reduced salivary adiponectin (p<0.001) and visfatin levels (p<0.05), and no changes in salivary resistin levels. Moreover, diurnal variation of salivary cortisol was lost. In elite RG's salivary adiponectin is upregulated and salivary visfatin is downregulated after chronic intensive exercise and negative energy balance, while both salivary adiponectin and visfatin levels are suppressed after short term intensive anaerobic exercise.

Salivary concentration of progesterone and cortisol significantly differs across individuals after correcting for blood hormone values

Between-individual variation of salivary progesterone (P4) and cortisol levels does not always closely reflect blood hormone concentrations. This may be partly a function of individual differences in salivary hormone excretion. We tested whether time of day at sampling and ethnicity contributed to individual variation in salivary hormones after adjusting for blood hormone levels. Forty-three Caucasian and 15 Japanese women (18-34 years) collected four sets of matched dried blood spot (DBS) and saliva specimens across a menstrual cycle (N = 232 specimen sets). Linear fixed-effects (LFE) models were used to estimate the effects of diurnal variation and ethnicity on salivary P4 and cortisol while adjusting for DBS levels. For each hormone, women with exclusively positive or negative residuals (unexplained variance) from the LFE models were categorized as high- or low-saliva-to-DBS hormone ratio (SDR; high or low salivary secretors), respectively. We found that salivary P4 (P < 0.05) was significantly higher in early morning compared to the afternoon, after controlling for DBS levels, ethnicity, and BMI. After further adjusting for this diurnal effect, significant individual variation in salivary P4 and cortisol remained: sixteen and nine women, respectively were categorized as low or high salivary secretors for both hormones (P < 0.001), suggesting systematic individual-specific variation of salivary hormonal concentration. We conclude that when saliva is used to quantify P4 or cortisol levels, time of day at sampling should be controlled. Even with this adjustment, salivary P4 and cortisol do not closely mirror between- individual variation of serum P4 and cortisol in a substantial proportion of individuals.

Depressive symptoms and cortisol variability prior to surgery for suspected endometrial cancer

Endometrial cancer (EC) is the most common type of gynecologic cancer affecting women; however, very little research has examined relationships between psychological factors and hypothalamic-pituitary-adrenal (HPA) axis dysregulation in this population. The current study examined relations between depressive/anxious symptoms and salivary cortisol diurnal rhythm and variability in women undergoing surgery for suspected endometrial cancer. Depressive and anxious symptoms were measured prior to surgery using the Structured Interview Guide for the Hamilton Depression Inventory (SIGH-AD). Saliva was collected four times a day for the 3 days prior to surgery and then assayed by ELISA to obtain cortisol concentrations. Cortisol slopes and intraindividual variability were then calculated across subjects. Relations between depressive/anxious symptoms and cortisol indices were examined using multilevel modeling and linear regression analyses. Participants were 82 women with nonmetastatic endometrial cancer. Anxious symptoms were not associated with either cortisol slope or intraindividual variability, and depressive symptoms were unrelated to cortisol slope. However, after controlling for presence of poorer prognosis cancer subtypes, greater depressive symptoms (excluding symptoms possibly/definitely due to health/treatment factors) in the week preceding surgery were significantly related to greater cortisol intraindividual variability (β=.214; p<.05). These results suggest that depressive symptoms prior to surgery for suspected endometrial cancer are related to greater cortisol intraindividual variability, which is suggestive of more erratic HPA axis arousal. Future research should examine whether mood symptoms may be associated with compromised health outcomes via erratic HPA axis arousal in this population.

Work hours and cortisol variation from non-working to working days

This study aims at modelling the relationship between the number of work hours per week and cortisol variation across 3days by comparing non-working day to working day in a population of day-shift workers. Questionnaire data and saliva samples for cortisol analysis were collected on 132day-shift workers employed in 13 workplaces in Canada. Consenting workers provided 5 saliva samples a day (awaking, 30min after awaking, 2p.m., 4p.m., bedtime) repeated 3 times (Saturday, Tuesday, Thursday) over a week, to provide measures at work and non-work times and settings. Multilevel regression models were estimated from cortisol measurements at each occasion within a day at level-1, days at level-2 and workers at level-3. Controlling for gender and age, results revealed significant variations in salivary cortisol concentration between sample, day and worker levels. Cortisol increases linearly from non-working day to work days and work hours per week interacted with days, revealing a positive association between the number of work hours per week and cortisol concentrations during these days. Work hours per week did not interact with awaking, 30min after awaking, 2p.m., 4p.m., and bedtime cortisol concentrations. Gender and age had neither main effects nor interaction effects. No significant cortisol variations were found between workplaces. These results suggest that work hours act as a stressor that is associated with significant variations in cortisol concentrations over working days. Non-working days may contribute to stress reduction in workers who experience longer work hours.

운동 강도별 동일 회복이 혈중 Cortisol과 Catecholamine 호르몬 변화에 미치는 영향

Abstract This study set out to investigate the effects of the same amount of resting(30 minutes) after VO 2 max 20%, 40%, and 60% exercise on the variation of cortisol and catecholamine, serum stress hormones. The research efforts led to the following conclusions:First, there were no significant differences in serum cortisol concentration between the VO 2 max 20% group and theVO 2 max 40% group, but there were some significant differences in the significance level of p=.002 in the VO 2 max 60% group.Second, there were no significant differences in serum catecholamine concentration between the VO 2 max 20% groupand the VO 2 max 40% group, but there were some significant differences in the significance level of p=.001 in theVO 2 max 60% group.Third, no significant differences were found in the changing rates of serum cortisol concentration between right afterexercise and during break among different levels of exercise intensity according to measuring time. Fourth, there weresignificant differences in the changing rates of serum catecholamine concentration in the significance level of p=.000right after exercise and in the significance level of p=.034 during break In short, there were significant differencesonly in the VO

The influence of age on plasma serotonin levels in Thoroughbred horses

The aim of this study was to investigate the influence of age on Thoroughbred horse plasma serotonin (5-HT) levels, measured in platelet poor plasma samples of clinically healthy horses. The analyses of plasma 5-HT amounts, with plasma tryptophan, the 5-HT precursor, were performed by reverse phase HPLC with electrochemical detector. Cortisol levels were also detected by ELISA kits. Both plasma 5-HT and tryptophan levels were significantly higher in foals compared to adult horses, thus suggesting a different rate of 5-HT synthesis correlated to age. No significant difference of cortisol amounts age-related was measured, probably because of the variability of plasma cortisol, which is known to be the result of many influences. In foals, the positive correlation between plasma tryptophan and cortisol (r=0.75; P<0.05) could be linked to growth processes. In adult horses, the negative correlation (r=−0.73; P<0.05) between 5-HT and cortisol was explained on the basis of the relation of serotonergic system with hypothalamic–pituitary–adrenal axis. These results showed an influence of age on plasma 5-HT concentrations, suggesting an interaction of this biological variable with plasma 5-HT metabolism.

Social correlates of variation in urinary cortisol in wild male bonobos (Pan paniscus)

Cortisol excretion in males of group living species is often associated with social rank and competition for oestrous females. Rank-related patterns of cortisol levels can be used to study mechanisms of rank maintenance and costs associated with mate competition. Bonobos (Pan paniscus) are interesting because males form a linear dominance hierarchy but are not dominant over females and therefore aggressive male–male competition over access to females alone is not considered to be a successful reproductive strategy. In this study on social correlates of urinary cortisol in wild male bonobos, we investigated the relationship between cortisol levels and several aspects of mate competition, including male rank, aggression rates, and association time with oestrous females. We found that cortisol levels correlated positively with dominance rank when oestrous females were present, but not when they were absent. This result is consistent with the idea that aggressive behaviour plays a minor role in maintenance of high rank. While aggression received from males and females explained within-individual variation in cortisol levels, it was the time spent in association with oestrous females that best explained between-individual variation in male cortisol levels. The observed increase in male cortisol may be associated with spatial proximity to oestrous females and could result from anticipated aggression from other group members, reduced feeding time in the males, or a combination of both.

Depth and duration of hypoglycaemia achieved during the insulin tolerance test

The insulin tolerance test (ITT) is the gold standard for assessment of the pituitary adrenal axis but its use is limited because of concerns relating to the risk of hypoglycaemia. This study examined the depth and duration of hypoglycaemia achieved during the test in a large cohort of patients. Two hundred and twenty ITTs were performed from 2005 to 2010. A 1200-bed University Teaching Hospital. Two hundred and twenty ITTs were carried out in patients with suspected or known pituitary disorders. Intravenous insulin was administered to achieve nadir plasma glucose (NPG) of 2.2 mmol/l (39.6 mg/dl). Blood chemistry to show the cortisol and GH response to hypoglycaemic stress was measured. Predictors of depth and duration of hypoglycaemia, adverse events and within-subject variability of nadir glucose, peak cortisol and peak GH were studied. Thirty percent of the cohort achieved a nadir glucose of <2.0 mmol/l (36 mg/dl) that lasted for 60 min or more. The NPG correlated positively with fasting plasma glucose (FPG; r=0:56; P<0.0005), insulin dose (r=0.27; P<0.0005) and weight (r=0.21; P<0.004). The within subject variability of nadir glucose was 15.2%, peak cortisol was 11.7% and peak GH was 6.4%. The factors determining nadir blood glucose were FPG (b=0.56, P<0.0005, 20% contribution) and weight (b=0.14, P<0.05, 2% contribution). The five patients with adverse events had NPG and insulin dose comparable with the rest of the population. The hypoglycaemia achieved during the ITT is much lower than the target required. However, adverse events are few and do not relate to the depth of hypoglycaemia.

Inter‐participant variability in circulating cortisol and nuclear hsp90 concentrations following short‐term aerobic activity

Salivary cortisol (CORT) concentrations were measured in healthy volunteers (n=66) before and after a 7.5‐minute guided aerobic exercise activity in order to determine fluctuations in endogenous CORT levels and exercise‐induced CORT response. Single nucleotide polymorphisms (SNPs) within DNA encoding the glucocorticoid receptor (GR) cortisol binding domain and differences in CORT‐associated proteins (i.e. GR and hsp90) were measured in white blood cell samples from a subset of participants (n=19). Pre‐ to 20 minute post‐activity CORT levels ranged from a 60% decrease to &gt;300% increase. Interestingly, the group of participants whose CORT levels exhibited the greatest decrease had significantly higher pre‐activity CORT levels when compared to all other participant groups. No correlations were detected between CORT variability and collected demographic data. Participants showing the greatest pre‐ to post‐activity CORT decrease and those showing highest pre‐activity CORT levels had significantly elevated concentrations of nuclear hsp90 compared to other participant groups. One SNP was detected, occurring in 3 of the 19 participants and representing a synonymous AAT&gt;AAC polymorphism at GR protein residue 766. These data demonstrate inter‐person differences in baseline CORT levels, variability in CORT response, and nuclear hsp90 concentrations are readily detected and potentially interrelated.

Mind matters in cancer survival

The very name "psycho-oncology" implies interaction between brain and body. One of the most intriguing scientific questions for the field is whether or not living better may also mean living longer. Randomized intervention trials examining this question will be reviewed. The majority show a survival advantage for patients randomized to psychologically effective interventions for individuals with a variety of cancers, including breast, melanoma, gastrointestinal, lymphoma, and lung cancers. Importantly, for breast and other cancers, when aggressive anti-tumor treatments are less effective, supportive approaches appear to become more useful. This is highlighted by a recent randomized clinical trial of palliative care for non-small cell lung cancer patients.There is growing evidence that disruption of circadian rhythms, including rest-activity patterns and hypothalamic-pituitary-adrenal (HPA) axis function, affects cancer risk and progression. Women with metastatic breast cancer have flatter diurnal cortisol patterns than normal, and the degree of loss of daily variation in cortisol predicts earlier mortality. Mechanisms by which abnormal cortisol patterns affect metabolism, gene expression, and immune function are reviewed. The HPA hyperactivity associated with depression can produce elevated levels of cytokines that affect the brain. Tumor cells can, in turn, co-opt certain mediators of inflammation such as NFkB, interleukin-6, and angiogenic factors to promote metastasis. Also, exposure to elevated levels of norepinephrine triggers release of vascular endothelial growth factor, which facilitates tumor growth. Therefore, the stress of advancing cancer and management of it is associated with endocrine, immune, and autonomic dysfunction that has consequences for host resistance to cancer progression.

Time‐of‐day effects in arousal: disrupted diurnal cortisol profiles in children with ADHD

Fluctuations in attention-deficit hyperactivity disorder (ADHD) symptoms related to regulatory deficits in arousal states are themselves characterized by circadian rhythms. Although cortisol is an important circadian arousal-related marker, studies focusing on across-the-day cortisol variations in ADHD are scarce. There is no study with multiple measurements to take into account interday and intraday variability. Salivary cortisol was sampled five times a day (awakening, 30 min after awakening, noon, 4 p.m., 8 p.m.) across five consecutive days in 33 children with ADHD (22 with and 11 without oppositional defiant disorder; ODD) and 33 class- and sex-matched controls (aged 6-12). The cortisol awakening response (increase from awakening to 30 min after awakening) and the diurnal cortisol profile (across-the-day variations) were compared for ADHD with ODD (ADHD + ODD) and without ODD (ADHD) subgroups and the control group. The cortisol awakening response was not significantly different between groups. However, longitudinal analyses to evaluate cortisol profiles across the day revealed a significant Group × Time effect (p < .001). More specifically, compared to each other, the ADHD subgroup showed a flatter slope with relative morning hypo-arousal and evening hyperarousal, whereas the ADHD + ODD subgroup showed a steeper slope with relative morning hyperarousal and evening hypo-arousal (p < .001). Findings support time-related arousal disruptions in children with ADHD associated with the presence or absence of ODD comorbidity. We recommend research on cortisol in larger samples for a better understanding of arousal mechanisms involved in ADHD not only with and without ODD but also with other comorbidities which may have implications for timing of arousal-based treatments.

Altered Psychobiological Responsiveness in Women With Irritable Bowel Syndrome

Although stress has been considered an important pathophysiological factor in irritable bowel syndrome (IBS), there is incomplete understanding of its physiological mechanisms. The current study was designed to compare diurnal hypothalamic-pituitary-adrenal (HPA) axis activity in IBS patients and controls and their psychobiological response to a psychosocial stressor. Basal and stimulated HPA axis activity was assessed in 57 women with IBS and 20 matched controls. Psychiatric comorbidity was assessed using a standardized clinical interview. Salivary morning cortisol and diurnal profile were obtained, and the Trier Social Stress Test (TSST) was administered. Levels of cortisol and adrenocorticotropic hormone (ACTH) were measured before and within 1 hour after the stressor. Overall stress experience and stress related to the TSST were assessed using standardized questionnaires. All subjects showed intact circadian variation of cortisol. However, IBS patients with predominant diarrhea exhibited substantially heightened cortisol levels at awakening (p < .03) and a blunted cortisol awakening response. In response to the TSST, patients exhibited significantly blunted cortisol (p < .05) and slightly attenuated ACTH secretion compared with controls. During the recovery period, ACTH levels were significantly lower (p < .04) in patients than those in healthy subjects. Women with IBS perceived higher stress susceptibility than control subjects did (p < .01). The enhanced morning cortisol levels in one subgroup of IBS patients may indicate an association between basal HPA axis activity and predominant bowel habit. The downregulated HPA axis reactivity in IBS after the TSST suggests a downregulated sensitivity of the endocrine system. On the contrary, all subjective stress ratings were increased in the IBS group, which may indicate increased stress susceptibility.

Complementary medicine for fatigue and cortisol variability in breast cancer survivors

Complementary medicine for fatigue and cortisol variability in breast cancer survivors

Reply to complementary medicine for fatigue and cortisol variability in breast cancer survivors

Reply to complementary medicine for fatigue and cortisol variability in breast cancer survivors

Reproducibility and performance of one or two samples of salivary cortisol in the diagnosis of Cushing’s syndrome using an automated immunoassay system

The purpose of this article is to evaluate the variability and reproducibility of late night salivary cortisol (LNSC) using electrochemiluminescence immunoassay (ECLIA) and compare the accuracy of one or two samples in diagnosis of Cushing's syndrome (CS). We prospectively included 64 healthy volunteers (HV), 35 patients with clinically suspected CS (S), and 26 patients with confirmed CS. Nine patients in the CS group had 24-h urinary free cortisol (UFC) less than two times the upper limit of normal (mild CS). UFC and two consecutive LNSC (LNSC1, LNSC2) were collected at home. All patients in the S group had normal UFC and low-dose dexamethasone suppression test. No differences were found between the HV and S groups in UFC, LNSC1, and LNSC2. Intra-individual variability between the two samples of LNSC was 22% in HV (1.6-91%), 32% in the S group (1.6-144%), and 51% (1.6-156%) in the CS group. Variability was higher in CS patients than those in the HV (P<0.001) and S groups (P=0.05). The AUC of LNSC1 was 0.945 (IC 95% 0.880-1.004); when considering the highest LNSC, the AUC was 0.980 (IC 95% 0.954-1.007) (P<0.01). We found 23% of discordant LNSC in the S group and 11% in the CS group. Three patients with CS had only one elevated LNSC, all of them with mild CS. Our results suggest that LNSC is variable, and reproducibility is affected in both CS and S patients. We found significant improvements in the diagnostic accuracy of the LNSC measurement by obtaining two samples.

Comparing biobehavioral profiles across two social stress paradigms in children with and without autism spectrum disorders.

BackgroundAutism spectrum disorders (ASD) are defined by impairment in reciprocal social interaction and flexible adaptation to the environment. This study compared physiological stress in children with and without ASD exposed to two social stress protocols. We hypothesized that the ASD group would show heightened initial and enduring cortisol levels to the social stressors, which would be moderated by age and intelligence.MethodsTwenty-seven children with ASD and 32 with typical development (TYP) completed a standardized social-evaluative performance task and a validated paradigm of social play with peers. Physiological stress was measured by salivary cortisol at nine time points. Statistical approaches included repeated-measures linear mixed models and correlation analyses.ResultsThe average cortisol level of both groups during initial exposure to social situations was significantly greater than baseline levels (ASD, P = 0.018; TYP, P = 0.006). Stress responsivity was significantly different between the groups; the TYP group showed a significant reduction in cortisol over time (P = 0.023), whereas the ASD group maintained an elevated cortisol level (P >0.05). The ASD group evidenced greater variability in between-group, within-group and intra-individual analyses. Age was a positive moderator of stress for the ASD group (P = 0.047), whereas IQ was a negative moderator for the TYP group (P = 0.061).ConclusionsInitial stress to novel social scenarios is idiosyncratic and predictive of subsequent exposure. Amidst significant variability in cortisol, children with ASD show enhanced and sustained social stress that increases with age. Developmental and cognitive factors differentially moderate stress in children with ASD and TYP, respectively. A model of neuroendocrine reactivity is proposed.

Plasma Free Cortisol and B-Type Natriuretic Peptide in Septic Shock

Previous studies of patients with septic shock have independently demonstrated alterations in plasma concentrations of B-type natriuretic peptide and plasma free cortisol. Previous data suggest that a reciprocal relationship might exist. However, the relationship between these hormones in patients with septic shock is unclear. We sought to compare paired measurement of both B-type natriuretic peptide and plasma free cortisol in a study of septic shock patients. Twenty-one consecutive adult patients from a tertiary level, multidisciplinary intensive care unit underwent blood collection within 72 hours of developing septic shock. Mean ± SD Acute Physiology and Chronic Health Evaluation III score was 80.1 ± 23.8. Hospital mortality was 29%. Log plasma free cortisol demonstrated positive correlation with log B-type natriuretic peptide (r=0.55, P=0.019). Log plasma free cortisol also correlated with Acute Physiology and Chronic Health Evaluation III score (r=0.67, P <0.001) and noradrenaline dose (r=0.55, P=0.01). Acute Physiology and Chronic Health Evaluation III (P=0.001) and noradrenaline dose (P=0.02) were independent predictors of plasma free cortisol. A model incorporating both variables explained 68% of variation in plasma free cortisol (R-square=0.682). This study of patients with septic shock demonstrates a previously unappreciated positive correlation between plasma free cortisol and b-type natriuretic peptide concentration. Acute Physiology and Chronic Health Evaluation III score and noradrenaline dose were independent predictors of plasma free cortisol.

Natural variation in gestational cortisol is associated with patterns of growth in marmoset monkeys ( Callithrix geoffroyi)

High levels of prenatal cortisol have been previously reported to retard fetal growth. Although cortisol plays a pivotal role in prenatal maturation, heightened exposure to cortisol can result in lower body weights at birth, which have been shown to be associated with adult diseases like hypertension and cardiovascular disease. This study examines the relationship between natural variation in gestational cortisol and fetal and postnatal growth in marmoset monkeys. Urinary samples obtained during the mother’s gestation were analyzed for cortisol. Marmoset body mass index (BMI) was measured from birth through 540 days in 30- or 60-day intervals. Multi-level modeling was used to test if marmoset growth over time was predicted by changes in gestational cortisol controlling for time, sex, litter, and litter size. The results show that offspring exposed to intra-uterine environments with elevated levels of cortisol had lower linear BMI rates of change shortly after birth than did offspring exposed to lower levels of cortisol, but exhibited a higher curvilinear growth rate during adolescence. Average daily change in gestational cortisol during the first trimester had a stronger relationship with postnatal growth than change during the third trimester. Higher exposure to cortisol during gestation does alter developmental trajectories, however there appears to be a catch-up period during later post-natal growth. These observations contribute to a larger discussion about the relationship of maternal glucocorticoids on offspring development and the possibility of an earlier vulnerable developmental window.

Condition dependent intra-individual repeatability of stress-induced cortisol in a freshwater fish

The glucocorticoid (GC) stress response is thought to be an individual trait associated with behaviour and life history strategies. Studies exploring such relationships typically assume measured hormone values to be repeatable within an individual. However, repeatability of GCs has proven variable in wild animals and underlying reasons remain unknown. We assessed individual repeatability of circulating stress-induced cortisol, the primary GC in teleost fish, and glucose concentrations in a wild teleost fish held under consistent laboratory conditions. We also tested the hypothesis that the magnitude of intra-individual variability in stress-induced cortisol concentrations (“cortisol variability”) is influenced by body condition. Wild-caught bluegill sunfish ( Lepomis macrochirus) were subjected to repeated standardized stressors and blood sampled (3 times over 6 days) once cortisol concentrations peaked. Various indicators of fish condition, both whole body and physiological, were also measured. Overall, stress-induced circulating cortisol concentrations were repeatable but stress-induced glucose was not. Cortisol variability was related to Fulton's condition factor and size (eviscerated mass) where smaller fish in poor condition exhibited increased cortisol variability. The findings have implications for the interpretation of studies that examine correlates of GC concentrations as they suggest consistency in stress responsiveness is influenced by factors such as size and condition.