Morning Cortisol Concentrations Research Articles

Hypothalamic-pituitary-adrenal axis and sympathetic nervous system activities in Pima Indians and Caucasians

It has been proposed that both hypercortisolism and low sympathetic nervous system (SNS) activity contribute to obesity. Because glucocorticoids inhibit SNS activity, we hypothesized that hypercortisolism and low SNS activity may be found in association in Pima Indians, a population with a high prevalence of obesity. We therefore measured indices of hypothalamic-pituitary-adrenal (HPA) axis and SNS activities in 39 nondiabetic men, 20 Pimas (age, 30 ± 5 years; weight, 94 ± 26 kg; 35% ± 8% body fat [mean ± SD]) and 19 Caucasians (33 ± 9 years, 91 ± 23 kg, 28% ± 11% body fat). HPA axis activity was assessed by measurements of morning fasting plasma corticotropin (ACTH) and cortisol concentrations and 24-hour urinary free cortisol (UFC) excretion. SNS activity was assessed as muscle sympathetic nerve activity (MSNA) by microneurography and by measurement of catecholamines (fasting plasma concentration and 24-hour urinary excretion). Plasma ACTH and cortisol and UFC were similar in Pimas and Caucasians. MSNA was positively correlated with percent body fat ( r = .49, P = .002) and was lower in Pimas compared with Caucasians after adjustment for percent body fat (24 ± 9 v 31 ± 10 bursts/min, P = .04). We conclude that Pima Indians, a population with a high prevalence of obesity, have lower SNS activity but normal HPA axis activity compared with Caucasians.

Diurnal Variation of Adrenocortical Activity in Chronic Fatigue Syndrome

Baseline morning and evening serum cortisol and ACTH concentrations, and diurnal changes in hormone levels, were measured in 30 patients with chronic fatigue syndrome (CFS) but without concurrent depressive disorder and a control group of 15 weight-, age- and sex-matched healthy volunteers. Morning cortisol levels were non-significantly lower in CFS patients, while evening levels were non-significantly higher. ACTH concentrations were non-significantly higher in both the morning and evening. The diurnal change in cortisol levels was significantly less in CFS than in controls (p < 0.05). In CFS subjects, evening levels of cortisol correlated significantly with measures of general health and physical functioning, while diurnal change in cortisol was positively correlated with measures of functional improvement over the past year and current social functioning. These results suggest that there is a relationship between adrenocortical function and disability in CFS, but do not reveal the causal connection.

Sensitivity of mononuclear leucocytes to glucocorticoids in elderly hip-fracture patients resistant to suppression of plasma cortisol by dexamethasone.

Elderly women with proximal femur fracture show a prolonged increase in plasma cortisol, which could have undesirable catabolic effects. Suppression of cortisol by dexamethasone is impaired, suggesting resistance to glucocorticoid effects at feedback inhibitory sites. We therefore wished to find out whether peripheral glucocorticoid sensitivity is normal. Peripheral blood mononuclear leucocytes were used as a model tissue. Blood samples were taken from elderly women about 2 weeks after hip fracture and from elderly control women. Each patient was then given 1 mg dexamethasone at 2300 h followed by further sampling at 0800 and 1600 h the next day. Glucocorticoid-receptor binding parameters were measured by incubating whole cells with [3H]dexamethasone for 2 h at 37 degrees C. Inhibition of cell proliferation by dexamethasone was assessed by addition of [3H]thymidine to cells cultured for 65 h with concanavalin A. Cortisol and dexamethasone concentrations were measured in the dexamethasone suppression test. As expected, the hip-fracture patients had raised morning cortisol concentrations and impaired suppression by dexamethasone. The cells of the patients had similar numbers of glucocorticoid receptors to those of the control subjects but higher values for Kd (i.e. a lower binding affinity). The cells of the patients incorporated less [3H]thymidine than the control cells in the absence of dexamethasone. The percentage inhibition by a saturating concentration of dexamethasone was unchanged but the concentration giving half-maximal inhibition was decreased (sensitivity was increased) at the higher of the two concanavalin A concentrations used. These experiments in mononuclear leucocytes give no evidence of peripheral resistance to glucocorticoids in hip-fracture patients with impaired suppression of cortisol by dexamethasone.

Altered neuroendocrine activity in maltreated children related to symptoms of depression

AbstractThis study examined the effects of stressful environments on physiological and affective functioning among 131 maltreated school-aged children attending a summer day camp. Sixty-six nonmaltreated children also attending the camp served as a comparison group. Salivary Cortisol measures were obtained daily at 10:00 a.m. and at 4:00 p.m. Depression was measured using the Child Depression Inventory. Children with scores of 19 or higher were classified as depressed. Internalizing and externalizing behavior problems were determined from the Teacher Report Form of the Child Behavior Checklist. Children with t scores of 70 or higher were classified as having clinical levels of these problems. Maltreated children had slightly elevated afternoon Cortisol concentrations, but their morning concentrations did not differ significantly from those of nonmaltreated children. Neither clinical levels of depression, internalizing, or externalizing problems were predictive of the elevated afternoon values. Depression among maltreated children was, however, associated with altered activity of the hypothalamic-pituitary-adrenocortical (HPA) axis. Depressed maltreated children had lower morning Cortisol concentrations compared to nondepressed maltreated children and were more likely to show a rise rather than the expected decrease in Cortisol from morning to afternoon. These data replicated earlier findings. There was no evidence that depressed, nonmaltreated children exhibited this change in diurnal Cortisol activity.

Developmental and personality correlates of adrenocortical activity as indexed by salivary cortisol: Observations in the age range of 35 to 65 years

Unstimulated salivary cortisol concentrations were measured in 767 adults aged 35–65 yr over the course of one day. Interindividual differences in early morning cortisol concentrations showed consistent and significant relationships with demographic and psychological variables. Socioeconomic status was positively associated with cortisol levels. Relationships of cortisol levels with age were moderated by gender: for women, a negative regression of cortisol level on age was observed while no significant age effects were obtained for men. In bivariate and multivariate regression analyses, a positive association between cortisol levels and indicators of successful development and personal well-being was observed; these relationships were more pronounced for the male sample. Intradyadic correlations further revealed a slight but significant association of morning cortisol levels within married couples. The findings are discussed with respect to mediating developmental mechanisms and pathophysiological implications.

Cortisol response of gilts in tether stalls.

Several experiments were conducted to evaluate serum cortisol concentrations and the circadian rhythm of this hormone in gilts tethered in stalls. Control animals were penned individually. In the initial experiment, 18 nongravid gilts were placed in tether stalls after being in either tether stalls or individual pens for 2 wk. No significant differences were found in serum cortisol concentrations. In a second experiment, 16 ovariectomized gilts were placed in tether stalls or individual pens for up to 5 wk. Estrus was induced during wk 3 and 4. During the first day in tether stalls, serum cortisol concentrations increased (P less than .05) and the circadian rhythm of cortisol was disrupted for 4 d. During estrus, the circadian rhythm of cortisol was interrupted for several days in the gilts, regardless of housing. After 4 wk, morning concentrations of cortisol were higher for gilts in tether stalls. The results indicate that: 1) the initial response to tethering varies according to previous penning and handling experience, 2) although the circadian rhythm of cortisol was either altered or disrupted during estrus, such disruptions were not influenced by type of penning and 3) tether stalls may chronically increase cortisol concentrations in gilts.

Effect of inhaled beclomethasone dipropionate on saliva cortisol concentrations.

Serial saliva cortisol measurements were used to assess pituitary-adrenal function in a group of asthmatic children treated with beclomethasone dipropionate (400 micrograms daily). Asthmatic children who were not being treated with steroids and normal children were also studied for comparison. A diurnal cortisol rhythm was observed in all three groups. Early morning cortisol concentrations were significantly higher in the group treated with beclomethasone dipropionate than in the normal children; this may indicate a stress induced response to decreased morning peak expiratory flow. In both groups, plasma and salivary cortisol responses after adrenocorticotrophic hormone stimulation test were normal but peak cortisol concentrations showed a 7 fold increase over basal values in saliva compared with a three fold increase in plasma. Beclomethasone dipropionate does not suppress pituitary-adrenal function in children when used in recommended doses. Serial measurement of the salivary cortisol concentration is a simple, safe, and sensitive method for the routine monitoring of adrenal function in children treated with this steroid. Monitoring may be supplemented with an assessment of the adrenal response to adrenocorticotrophic hormone stimulation, if necessary.

Evidence for dopaminergic stimulation of growth velocity in some hypopituitary children.

The purpose of this study was to determine if endogenous hGH release, hence growth, in hypopituitary children could be potentiated by therapy with dopaminergic (DA) drugs namely, L-dopa or bromocriptine. The effect of DA therapy on other endocrine function was also examined. Subjects were nine prepubertal children (four girls and five boys) with bone ages (BA) ranging from 1.5-9.5 yr. They were diagnosed as having idiopathic GH deficiency on the basis of: 1) failure to grow at normal rates 2) lack of GH response to two provocative stimuli (oral L-dopa, and insulin-induced hypoglycemia) and 3) low somatomedin-C concentrations for sex and age. They were divided into two groups. Group I (n = 4) received L-dopa (15 mg/kg, orally, every 6 h) for 6 months. Group II (n = 5) received bromocriptine (1.25 mg, orally, every 12 h) for 6 months. At the end of 6 months of DA therapy, both groups received human GH (hGH) im (0.1 IU/kg, thrice weekly) for 6 months. The growth rate in group I increased to 5.7 +/- 0.6 (+/- SE) cm/yr during the 6 months from a pretreatment rate of 3.4 +/- 0.2 cm/yr. Individual increments ranged from 30-94% above pretreatment growth rates. Three of the four children had significantly increased height increments, and two children achieved growth rates normal for their BA. Similarly, the growth rate in group II increased to 4.8 +/- 0.8 cm/yr from the pretreatment rate of 2.9 +/- 0.3 cm/yr. Individual increments ranged from 46-100% above pretreatment growth rates. Three children in group II had significantly increased height increments, and two children had normal growth rates for BA. The growth increments during L-dopa therapy occurred in the three children who had significant increases in hGH and somatomedin-C; of the three children with significant growth increments during bromocriptine therapy, two had increases in somatomedin-C, and one achieved a normal peak hGH value. hGH therapy caused further acceleration of growth velocities in the majority of patients. DA therapy had no significant effect on basal gonadotropin, gonadal steroids, T4, TSH, or morning cortisol concentrations in the majority of children compared with their pretreatment values. The following conclusions were reached. Dopaminergic therapy by itself, i.e. L-dopa or bromocriptine administration, induced linear growth in some hypopituitary children without significantly affecting basal concentrations of LH, FSH, gonadal steroids, T4, TSH, or cortisol. The effect this therapy could have in potentiating exogenous GH and/or possible GRH therapy is worthy of further investigation.

Effects of daily 30 mcg d-norgestrel on growth hormone and cortisol

The effects of d-norgestrel on serum growth hormone and cortisol were determined in 9 healthy Thai women, who took 30 mcg d-norgestrel tablet daily for 12 months. Growth hormone (both fasting and during OGTT) and morning cortisol concentrations were measured before and after 6 and 12 months. It was found that growth hormone concentrations tended to decrease but were not statistically significant. Patterns of growth hormone in relation to glucose and insulin measured during OGTT were similar throughout the study. The morning cortisol values slightly increased after treatment. The limited data from this study suggested that d-norgestrel, at the daily dose of 30 mcg, did not significantly alter serum growth hormone and cortisol levels in the group of Thai women after one year's time of use.

Adrenocortical suppression in workers employed in manufacturing synthetic glucocorticosteroids: solutions to a problem.

Earlier studies showed gross adrenocortical suppression in three workers employed in manufacturing synthetic glucocorticoids. A further nine had either recognisable abnormalities of their responses to tetracosactrin or evidence of chronic skin contact with glucocorticoids. By 1978 the mean morning cortisol concentration of 20 workers employed in active steroid processes was 235 nmol/1 +/- 28.6 (8.5 microgram/ml +/- 1.04), which was significantly lower than the value of 428 nmol/l +/- 37.7 (15.5 microgram/ml +/- 1.40) obtained in a control group of 19 men (p less than 0.005). The mean morning cortisol of workers employed in processing steroids believed to be physiologically inactive, 306 nmol/l +/- 22.4 (11.1 microgram/ml +/- 0.81), was also significantly lower than this control group (0.01 greater than p greater than 0.005). Improvement of protection for workers together with operational and plant changes resulted in a significant rise in the mean morning cortisol values of workers until, in 1979, men employed in all steroid processes had concentrations that did not differ from those of a control group.

Estrone, 17 beta-estradiol, and cortisol in serum of peripartum rhesus monkeys.

Prepartum maternal serum concentrations of progesterone and 5α-pregnane-3,20-dione are reportedly higher at 2100 h than at 0900 h (Sholl, S. A., J. A. Robinson, and R. C. Wolf, Endocrinology, in press). These findings were interpreted to mean thatplacental progestin secretion is elevated during the evening. The present study was initiated to determine whether the fetoplacental unit exhibits a similar pattern of secretory activity as might be reflected in a temporal alteration in serum estrone, 17β-estradiol, and cortisol concentrations in the mother and whether there are consistent daily changes in morningevening steroid levels preceding parturition. Steroid levels were measured by radioligand assays of maternal systemic serum obtained at 0900 and 2100 h around the time of parturition. Estrogen levels in the four animals examined increased during the 9 days immediately preceding parturition to maximum levels on the day of delivery. In direct contrast to the reported diurnal alteration in progesterone and 5a-pregnane-3,20-dione, the prepartum concentrations of estrone, 17β-estradiol, and cortisol were substantially higher at 0900 than at 2100 h. No change occurred in the magnitude of this difference as gestation advanced. After parturition, serum estrogen levels were substantially lower. In two monkeys nursing their infants, no diurnal variation in hormone concentration was detected during the 16 days after parturition; thus, it would appear that the prepartum variation originated in the fetoplacental unit and not in the ovary. Unlike estrogen, day to day cortisol levels did not change during the final 2 weeks of gestation or immediately after delivery. However, morning cortisol concentration on day 16 postpartum was substantially lower than on the day after parturition. A nocturnal decline in hormone concentration, which probably originated in the mother, was observed in both pre- and postpartum animals. The prepartum increase in estrogen levels suggests an estrogen involvement in parturition. Moreover, the diurnal fluctuation in circulating estrogen may be important in restricting parturition to the evening or early morning. The initiator(s) of this prepartum estrogen cyclicity remains to be elucidated; however, this change may be effected by an alteration in fetal adrenal activity mediated by negative feedback of cortisol on fetal pituitary ACTH secretion.