Urinary Free Cortisol Excretion Research Articles

Response of the hypothalamic-pituitary-adrenal axis to small dose arginine-vasopressin and daily urinary free cortisol before and after alprazolam pre-treatment differs in obesity

Arginine vasopressin (AVP) has a central role in the response of the hypothalamic-pituitary-adrenal (HPA) axis to stress conditions. A low dose of AVP has been shown to have a modest, but significant effect on ACTH response in normal weight subjects. The aim of this study was to test the response of the HPA axis in obese subjects in order to assess eventual primary neuroendocrine alterations, previously demonstrated by using AVP combined with corticotropin releasing hormone (CRH). In addition, given its central inhibitory action on the HPA axis, we investigated whether the suppressive capacity of alprazolam (APZ) pretreatment on the hormone response to low-dose AVP challenge and daily urinary free cortisol (UFC) excretion rate may be altered in the presence of obesity. Fifteen overweight or obese women and eight normal-weight controls randomly underwent two low-dose AVP tests (0.3 UI iv bolus), one without (AVP test) and the other preceded by APZ administration (0.5 mg at midnight and 0.5 mg 90 min before the test in the morning at 08:30 h) (APZ/AVP test). Blood samples for ACTH and cortisol assay were obtained at baseline and throughout each test. The day before each test, 24h-UFC/ creatinine was also mea-sured. Basal ACTH levels were similar in the two groups, whereas cortisol concentrations were significantly lower in the overweight/obese group. Overweight/obese women had higher ACTH and cortisol responses to the AVP tests and significantly greater hormone inhibition after APZ than controls. In both groups, AVP-induced delta-peak cortisol values before and after APZ pre-treatment were significantly correlated. Body fat distribution had no effect on the HPA axis response to AVP either before or after APZ. Moreover, APZ decreased 24h-UFC/creatinine values unsignificantly in controls and by approximately 50% in the overweight/obese subjects. These changes were unrelated to the cortisol response to the AVP test before and after APZ pretreatment. On the other hand, percent changes of 24h-UFC/creatinine after APZ were negatively related to the body mass index (BMI) but positively with waist circumference values, which indicates that the abdominal obesity phenotype may counteract the 24 h-UFC/creatinine that would be expected on the basis of BMI values. Our data further support the concept that in women obesity may represent a condition of hyperresponsiveness or hypersensitivity of the HPA axis to neuroendocrine stimuli, which appear to be independent of feedback control. In addition, the data on the inhibiting capacity of APZ on UFC excretion confirm that the alterations of the HPA axis in obesity is particularly evident in the abdominal phenotype.

Hippocampal volume, memory, and cortisol status in major depressive disorder: effects of treatment

Background Depression has been linked to stress, memory deficits, and hypercortisolemia. However, the relationships between depression, hippocampal structure and function, and cortisol levels are unclear and the effects of antidepressant treatment on the measures are not well studied. Methods Whole hippocampal volume, performance on verbal and visual declarative memory function and cortisol status was evaluated in 38 subjects with major depressive disorder (MDD) and 33 healthy subjects. All measures were repeated in a subgroup ( n = 22) of depressed patients after successful selective serotonin reuptake inhibitor (SSRI) treatment. Results Hippocampal volume was not significantly different between patients with untreated MMD and healthy subjects, after controlling for whole brain volume, age and gender. However, depressed subjects had significantly greater deficits in delayed memory and percent retention on the verbal portion of the Wechsler Memory Scale—Revised (WMS-R) compared with healthy subjects, without significant differences in visual memory, attention, vigilance, or distractibility. Baseline plasma or urinary free cortisol (UFC) was not related to either hippocampal volume or memory deficits. Successful treatment with antidepressants did not change hippocampal volume but did result in a significant improvement in memory function and a reduction in UFC excretion. Conclusions Medication-free nonelderly depressed outpatients without alcohol dependence or adverse experiences in childhood had normal hippocampal volume. Focal declarative memory deficits in depression supported localized hippocampal dysfunction in depressed patients. Treatment with antidepressants significantly improved memory and depression but did not alter hippocampal volume, suggesting that antidepressants may improve hippocampal function in the absence of detectable structural changes.

Familial/sporadic glucocorticoid resistance: clinical phenotype and molecular mechanisms.

Glucocorticoids regulate a variety of biologic processes and exert profound influences on many physiologic functions. Their actions are mediated by the glucocorticoid receptor (GR), which belongs to the nuclear receptor family of ligand-dependent transcription factors. Alterations in tissue sensitivity to glucocorticoids may manifest as states of resistance or hypersensitivity. Glucocorticoid resistance is a rare, familial or sporadic, condition characterized by generalized, partial target-tissue resistance to glucocorticoids. Compensatory elevations in circulating adrenocorticotropic hormone (ACTH) concentrations lead to increased production of adrenal steroids with mineralocorticoid and/or androgenic activity and their corresponding clinical manifestations, as well as increased urinary free-cortisol excretion in the absence of symptomatology suggestive of hypercortisolism. The molecular basis of the condition has been ascribed to mutations in the GR gene, which impair normal glucocorticoid signal transduction, altering tissue sensitivity to glucocorticoids. The present review focuses on the mechanisms of GR action and the clinical manifestations and molecular mechanisms of familial/sporadic glucocorticoid resistance.

Endocrinologic and psychologic evaluation of 21-hydroxylase deficiency carriers and matched normal subjects: evidence for physical and/or psychologic vulnerability to stress.

Carriers of congenital adrenal hyperplasia due to 21-hydroxylase (21-OH) deficiency demonstrate increased secretion of cortisol precursors after ACTH stimulation, suggestive of impaired cortisol production and compensatory increases in hypothalamic CRH secretion. Because both cortisol and CRH have behavioral effects, and hypothalamic CRH hypersecretion has been associated with chronic states of anxiety and depression, we performed endocrine and psychologic studies in consecutively admitted parents of patients with classic congenital adrenal hyperplasia due to 21-OH deficiency and parents of children with other chronic endocrine disorders. The number of excluded carriers because of pathologic reasons was higher than that of controls (P = 0.05). Carriers of 21-OH deficiency had a lower mean 24-h urinary free cortisol excretion (26.4 +/- 3.4 vs. 42.7 +/- 6.4 microg/d, P = 0.03) and higher peak ACTH (75.7 +/- 8.1 vs. 54.2 +/- 5.9 pg/ml, P = 0.04) and 17-hydroxyprogesterone (224.2 +/- 28.1 vs. 107.1 +/- 12.5 ng/dl, P < 0.001) concentrations post CRH stimulation than control subjects. Cortisol and androstenedione responses were similar in the two groups. Psychometric assessment performed by administering the State-Anxiety Inventory, Beck Depression Inventory, Profile of Mood States, Symptom Checklist-90R, and Temperament and Character Inventory revealed no differences between the two subject groups. Interestingly, a stepwise multiple linear regression model analysis in each population sample revealed that in carriers of 21-OH deficiency but not in the control subjects, a lower mean 24-h urinary free cortisol excretion and a higher ACTH response to ovine CRH stimulation predicted predisposition to obsessive-compulsive behavior, novelty seeking, reward dependence, and harm avoidance. We conclude that carriers of 21-OH deficiency appear to have mild hypocortisolism and compensatory changes of CRH secretion secondary to lower cortisol concentrations. These changes might predict mild predisposition of these subjects to physical and psychologic pathology, suggesting that larger studies are necessary.

Diminished urinary free cortisol excretion in patients with moderate and severe renal impairment.

The diagnosis of Cushing syndrome remains a challenge for most general clinicians and even endocrinologists. Because the clinical features of Cushing syndrome overlap with those in some healthy obese individuals, biochemical investigations play an important role. The 24-h urinary free cortisol excretion is widely used because of its relatively good sensitivity and specificity (1)(2). Although salivary cortisol has been recommended for screening of Cushing syndrome (3), this assay has not been widely available. Because plasma free cortisol is filtered through the glomeruli with partial tubular reabsorption, the amount of free cortisol appearing in the urine is theoretically dependent on the glomerular filtration rate. However, the high reliability of using 24-h urinary cortisol excretion for the diagnosis of Cushing syndrome implies that urinary excretion of cortisol is relatively unaffected by renal function. In patients with confirmed Cushing disease and severe renal impairment, the urinary free cortisol excretion rate reportedly is normal despite markedly increased plasma cortisol (4)(5)(6). The relationship between glomerular filtration rate and urinary cortisol excretion has not been documented in patients with different degrees of renal impairment. We selected 100 leftover portions of urine samples that had been sent for the measurement of creatinine clearance (CrCl) in the Prince of Wales Hospital of Hong Kong during September, October, and November 2002. All patients were given clear instructions by an experienced nurse to ensure the completeness of 24-h urine collection. Simultaneous serum samples were also received for the …

Non‐physiological levels of circulating cortisol in growth hormone‐treated hypopituitary adults after conventional cortisone substitution

Objective: To assess the usefulness of measuring plasma cortisol profiles in growth hormone‐treated hypopituitary adults and to compare these with cortisol levels in healthy controls. Methods: Eleven ACTH‐deficient adult patients received 12.5 mg cortisone‐acetate orally at 16.00 h and 25 mg at 07.00 h. The patients arrived in the ward at 12.00 h. After tablet intake at 16.00 h, samples for serum cortisol were taken at hourly intervals for the next 24 h, except between 07.00 and 12.00 h when samples were drawn every half hour; 24‐h urinary free cortisol (24‐h‐UFC) excretion was collected simultaneously. For comparison, 8 healthy controls were investigated. Results: The patients had circulating cortisol levels with very low plasma cortisol at 07.00 h before their morning dose of cortisone acetate. At the same time period, controls had their highest plasma cortisol levels. After tablet intake the patients had a rapid initial absorption of cortisol, but a marked variability in the morning peak levels (Cmax), and the Cmax was in general higher and occurred 90 min later than the Cmax in the controls. The 24‐h‐UFC excretion and 24‐h area under the curve (24‐h‐AUC) did not differ between patients and controls. The female patients had higher 24‐h‐AUC for plasma cortisol (p=0.032) and tended to have higher plasma cortisol peaks in the morning, but had levels of 24‐h‐UFC similar to those of the male patients. Conclusions: Conventional cortisone substitution with a twice‐daily replacement regimen in hypopituitary adults results in abnormal circulating cortisol profiles with low or non‐measurable morning values and variable individual peaks. This suggests that the present dosing schemes have to be improved and that cortisone substitution should be individualized.

Evidence supporting a role of glucocorticoids in short-term bone loss in burned children.

Children burned > or =40% total body surface area suffer acute bone loss. The reason(s) for this is uncertain. In order to determine whether high endogenous glucocorticoid production can contribute to the bone loss, we sequentially studied a total of 14 pediatric burn patients for bone histomorphometry; 7 of these patients and 4 controls were studied for characteristics of corticosteroid-induced bone loss, including decreased osteoblasts and down-regulation of the glucocorticoid receptor in bone. We then studied 4 of the burn patients and three controls for a decrease in markers of osteoblast differentiation, another feature of glucocorticoid toxicity. Bone biopsies were taken from each of the 14 burn patients a mean of 3 weeks post-burn. Histomorphometry was performed on one specimen ( n=7) and either glucocorticoid and mineralocorticoid receptor, collagen and alkaline phosphatase expression by RT-PCR ( n=7) or marrow stromal cell culture ( n=4) on the other. Patients were permitted a maximum of two biopsies for study. One biopsy was obtained intra-operatively from normal subjects during elective iliac crest alveolar bone grafting and compared with burn specimens for glucocorticoid receptors and marrow stromal cell culture. A 24 h urine specimen was obtained for free cortisol ( n=7). Histomorphometry revealed low osteoblast and osteoid surfaces and few detectable osteoblasts. Resorptive surfaces were also reduced. Glucocorticoid receptor alpha mRNA (GRalpha) was not decreased; however, there was a trend toward inverse relationships between urine free cortisol and GRalpha and type-1 collagen mRNA, r=-0.61 and -0.64, respectively, and a significantly lower mRNA for type-1 collagen in bone in burn vs control patients by the median test, lambda(2)=7.6 ( p<0.01). Markers of osteoblast differentiation, core-binding factor (cbf)a1, bone morphogenetic protein (BMP)-2, type-I collagen, and alkaline phosphatase were reduced in burn cell cultures compared with controls ( p<0.05). The eightfold elevation of urinary free cortisol excretion, low osteoblast number, decreased resorptive surface, and reduced markers of osteoblast differentiation are all consistent with an acute glucocorticoid effect on bone.

Dose distribution in hydrocortisone replacement therapy has a significant influence on urine free cortisol excretion.

We investigated the influence of dose distribution in hydrocortisone replacement therapy on urine free cortisol excretion. To this end, we measured 24-hour urine free cortisol (24-h UFC) in 13 patients with hypocortisolism. The patients took 25 mg hydrocortisone/day according to the following schedules: either a single 25 mg hydrocortisone dose at 8:00 a.m., or 15 mg hydrocortisone at 8:00 a.m. and 10 mg hydrocortisone at 2:00 p.m., or 5 mg hydrocortisone at 8:00 a.m., 10:00 a.m., 2:00 p.m., 6:00 p.m. and 10:00 p.m. 24-h UFC decreased significantly with increasing division of the daily 25 mg hydrocortisone dose. When taking 25 mg hydrocortisone in a single morning dose, the mean 24-h UFC was 649 +/- 52 nmol/day (mean +/- SEM). When the daily dose was divided into doses of 15 mg and 10 mg hydrocortisone, 24-h UFC was reduced by 28 % to 466 +/- 39 nmol/day (p < 0.002). After division into five doses of 5 mg, 24-h UFC was reduced by 42.8 % to 371 +/- 36 nmol/day (p < 0.001) compared to the single 25 mg dose. These data demonstrate that consideration of the dose distribution in hydrocortisone replacement therapy when analysing 24-h UFC is of clinical importance.

Influence of mirtazapine on urinary free cortisol excretion in depressed patients

Mirtazapine has been shown to acutely inhibit cortisol secretion in healthy subjects. In the present study, the impact of mirtazapine treatment on urinary free cortisol (UFC) excretion was investigated in depression. Twenty patients (six men, 14 women) suffering from major depression according to DSM-IV criteria were treated with mirtazapine for 3 weeks. The patients received 15 mg mirtazapine on day 0; 30 mg mirtazapine on day 1; and 45 mg mirtazapine per day from day 2 to the end of the study (day 21). UFC excretion was measured before treatment (day 1), at the beginning (day 0), after 1 week (day 7) and after 3 weeks (day 21) of treatment with mirtazapine. Urine samples were collected from 08:00 to 08:00 h the following day. On the days of urine sampling, the severity of depressive symptoms was assessed using the 21-item version of the Hamilton Rating Scale for Depression (21-HAMD). There was a significant reduction of UFC excretion during 3-week mirtazapine therapy, which was already obvious after the first day of treatment (day 0). However, there were no significant across-subjects correlations between UFC reduction and decrease in 21-HAMD sum scores. Apparently, the mirtazapine-induced rapid reduction of cortisol secretion in depressed patients is not necessarily correlated with a favorable therapeutic response.

Chronoecoepidemiology of “strain”: infradian chronomics of urinary cortisol and catecholamines during nightly exposure to noise

This meta-analysis of published data (Noise Health 5 (2002) 35 and 47) summarizing a survey for 40 days of the nightly excretion of urinary free cortisol, epinephrine and norepinephrine validates a circaseptan cortisol pattern anticipated and reported earlier for cortisol, here not detected for the catecholamines. We also quantify a circadecan (about 10-day) variation in nightly norepinephrine excretion, but not in the excretion of the other two hormones examined. About 4.2-day variations, common to norepinephrine and epinephrine, and an about 4.7-day variation in cortisol await further scrutiny, since these components were not anticipated. Infradian characteristics are quantified time-microscopically and differences among infradian aspects of the spectral element of endocrine chronomes (time structures; from chronos, time and nomos, rule) are demonstrated. Chronomics, the cartography of chronomes, reveals that “stress hormones” need to be examined separately in a budding chronoepidemiology seeking to detect how humans interact, mostly for better, sometimes for worse, with the undesirable features of the technology they create and of its consequences, such as aircraft noise.

Steroids in Adult Men With Type 1 Diabetes

To compare steroids and their associations in men with type 1 diabetes and healthy control subjects. We studied 52 adult men with type 1 diabetes without microvascular complications, compared with 53 control subjects matched for age and BMI. Steroids and their binding globulins were assessed in a single venous blood sample and a 24-h urine sample. In adult men with type 1 diabetes, total testosterone did not differ from healthy control subjects, but sex hormone-binding globulin (SHBG) (42 [14-83] vs. 26 [9-117] nmol/l, P < 0.001), cortisol-binding globulin (CBG; 0.87 +/- 0.17 vs. 0.73 +/- 0.10 nmol/l, P < 0.001), and cortisol levels (0.46 +/- 0.16 vs. 0.39 +/- 0.14 nmol/l, P < 0.01) were higher. The free testosterone index was lower (60 [17-139] vs. 82 [24-200], P < 0.001), and the calculated free testosterone was slightly lower (497 [115] vs. 542 [130], P < 0.064), but the pituitary-gonadal axis was not obviously affected in type 1 diabetes. The calculated free serum cortisol was not different, and 24-h urinary free cortisol excretion was lower in type 1 diabetes (121 [42-365] vs. 161 [55-284] nmol/24 h, P < 0.009). Testosterone was mainly associated with SHBG. Estimated portal insulin was a contributor to SHBG in control subjects but not in type 1 diabetes. Cortisol was associated with CBG. HbA(1c) contributed to CBG in men with diabetes but not in control subjects, whereas estimated portal insulin did not contribute. Adult men with fairly controlled type 1 diabetes without complications who are treated with subcutaneous insulin have a tendency to hypogonadism, as reflected by lower free testosterone levels in the presence of similar total testosterone levels and higher SHBG levels.

Altered hypothalamic–pituitary–adrenocortical function in rhesus monkeys ( Macaca mulatta) with self-injurious behavior

Individually housed rhesus monkeys sometimes spontaneously develop self-injurious behavior (SIB) in the form of self-directed biting that, on occasion, results in severe tissue damage and mutilation. We previously demonstrated lower levels of plasma cortisol in rhesus monkeys with a history of self-wounding (SW) when compared to non-wounders (NW). Furthermore, cortisol levels were negatively correlated with rates of self-directed biting. The present study was designed to further characterize the relationships between hypothalamic–pituitary–adrenocortical (HPA) activity, self-wounding, and self-directed biting. Basal 24-h urinary free cortisol excretion, the urinary free cortisol response to a low dose of dexamethasone, and the plasma cortisol response to ACTH were examined in 24 individually housed rhesus monkeys, based on wounding history, i.e. the presence/absence of a veterinary record of self-wounding, and current rates of self-directed biting, i.e. the median split of self-directed biting frequency (independent of wounding status). There were no reliable group differences on any of the physiological measures when analyzed by wounding history. However, the plasma cortisol response 30 min post-ACTH stimulation was significantly correlated with wounding recency, such that lower responsivity was associated with more recent wounding episodes. When the results were analyzed on the basis of biting frequency, high frequency biters (HFB) compared to low frequency biters (LFB) showed decreased HPA negative feedback sensitivity to dexamethasone and a trend towards an attenuated plasma cortisol response to ACTH stimulation. These findings suggest that SIB in socially reared monkeys is associated with complex changes in HPA axis function that are related to the expression of the pathology, i.e. self-directed biting, and to the recency of a wounding episode. It remains to be determined whether humans who exhibit SIB show similar alterations in HPA function.

Relationship between 24-hour urinary-free cortisol excretion and salivary cortisol levels sampled from awakening to bedtime in healthy subjects

The utility of repeated salivary cortisol sampling as a substitute for 24-hour urinary-free cortisol (UFC) assessment was examined. Forty-four participants completed both 24-hour collections and 6 salivary collections at wake-up, 08:00, 12:00, 16:00, 20:00 and bedtime, during the same 24-hour period. The results demonstrated that mean, maximum, and amplitude (maximum minus minimum) for salivary cortisol all correlated positively with urinary cortisol, but the associations of these variables with urinary-free cortisol excretion were relatively small. Furthermore, a single salivary sample taken at wake-up was as good an indicator of overall cortisol production as the measures derived from multiple salivary samples. An examination of subject compliance indicated that many subjects failed to collect the timed salivary collections as instructed. The authors conclude that diurnal salivary cortisol sampling versus 24-hour urinary cortisol collections are likely to provide different information about ambient hypothalamic-pituitary-adrenal productivity, and therefore these measures should not be used interchangeably. In addition, subject compliance is a serious consideration in designing studies that employ home salivary collections.

Urinary free cortisol increases in adolescent caucasian females during perimenarche.

Urinary free cortisol (UFC) excretion has been thought to be constant during female reproductive maturation when normalized for body surface area. We sought to determine whether there are longitudinal changes in urinary free cortisol excretion during perimenarche in adolescent females. We performed a longitudinal study of 24-h UFC excretion obtained at 6-month intervals over a 4-yr period in a cohort of 112 adolescent non-Hispanic white perimenarchal females from south central Pennsylvania. The overall mean values (mean +/- SD) for UFC/24 h for all measurements between ages 12 and 17 yr was 67.4 +/- 43.8 micro g/24 h (to convert to nanomoles per day, multiply by 2.759). In our model, we found a significant positive association between UFC excretion with both gynecological age (P = 0.002) and chronological age (P = 0.0001). For every incremental increase in Tanner stage, the UFC/BSA increased by 3.0 microg/24 h per square meter. Correcting the UFC values by both creatinine and BSA creates a fairly constant number (6.3 +/- 3.1 microg/mg per square meter per 24 h) over the age range 12-17 yr represented in this study. An increase in cortisol excretion may be part of normal reproductive maturation.

Absence of hypersensitivity to glucocorticoids in antiretroviral-associated lipodystrophy.

The lipodystrophy syndrome, which is associated with the use of antiretroviral drugs in some human immunodeficiency virus (HIV)-infected individuals, bears a striking similarity to the fat redistribution observed in Cushing's disease. Although urinary free cortisol excretion and glucocorticoid receptor binding affinity are not elevated in subjects with lipodystrophy, glucocorticoid action at the cellular level has not been examined in affected individuals. The objective of this study was to determine whether tissue sensitivity to glucocorticoids is increased in subjects with lipodystrophy taking protease inhibitors. Subjects included 11 HIV-infected men on protease inhibitor therapy with lipodystrophy and 10 control HIV-infected men not on protease inhibitor therapy and without lipodystrophy. Trunk to extremity fat ratio was measured by DXA. Dexamethasone suppression of peripheral blood mononuclear cell proliferation was measured as an index of tissue sensitivity to glucocorticoid action. Compared with the control group, subjects with lipodystrophy had a significant elevation of the trunk to extremity fat ratio [median (interquartile range): 2.9 (1.3) vs. 1.6 (1.2); p < 0.05]. The concentration of dexamethasone resulting in 50% maximal suppression of proliferation was 11.7 nM (9.3 nM) in subjects with lipodystrophy and 19.6 nM (9.7 nM) in control subjects (p = not significant), and the percentage minimal proliferation was 4% (12%) and 17% (18%) in the two groups, respectively (p = not significant). Despite the Cushingoid appearance of affected individuals, these data suggest that body fat redistribution in antiretroviral-associated lipodystrophy does not arise through an increase in postreceptor glucocorticoid signaling.

A woman who gained weight and became schizophrenic

Over 6 years, a 45-year old woman developed persecutory ideas, social withdrawal, self-neglect, and a thought disorder. Some months before her admission to our hospital in October, 2000, a psychiatrist noticed obesity and bruises on her forearms. She refused to cooperate with diagnostic procedures or treatment, and had to be put in the care of a legal guardian. When she came to our clinic, she was disoriented, depressed, lacked initiative, but denied being ill. Her attention span and memory were poor, she thought slowly, had false reasoning with a lack of consistency, and persecutory ideas without hallucinations. She had Cushingoid features with obesity (body-mass index 29), moon face, buffalo hump, skin atrophy, and hypertension, BP 160/110 mm Hg. Blood tests showed macrocytosis and decreased serum vitamin B12 at 159 pg/mL. Vitamin B12 injections and flupentixol had no effect on her mental state. A cranial magnetic resonance image and a lumbar spinal fluid analysis including angiotensin converting enzyme were normal. Urinary free cortisol excretion was elevated to 148·8 µg/day. Serum cortisol showed attenuated circadian rhythm (0800 h 22·6 µg/dL, 2400 h 9·8 µg/dL) and was not suppressed after 1 mg dexamethasone (baseline 14·3 µg/dL, after dexamethasone 19·5 µg/dL). Administration of corticotropin-releasing hormone (CRH) showed suppressed plasma ACTH not responding to CRH. A diagnosis of Cushing’s syndrome was made. An abdominal magnetic resonance tomogram showed a left adrenal mass, diameter 3·5 cm. Treatment with

Diagnostic tests for Cushing's syndrome.

The diagnosis of Cushing's syndrome rests on the demonstration of clinical features and biochemical abnormalities that reflect hypercortisolism. If a patient presents with typical clinical features such as weight gain with truncal obesity and supraclavicular fat deposition, wide purple striae, and proximal muscle weakness, the diagnosis is clear-cut and is nearly always substantiated by a 24-hour urine free cortisol excretion value more than four times the normal level. However, many patients present with signs and symptoms that are common in the general population, such as hypertension, generalized weight gain, reproductive abnormalities, and depression. Many of these patients have normal cortisol excretion and do not have Cushing's syndrome. Others have mild hypercortisolism caused by psychiatric disorders, obligate exercise, morbid obesity, sleep apnea, or uncontrolled diabetes mellitus. These patients may be confused with those with the true Cushing's syndrome, and thus are considered to have a "pseudo-Cushing" state. Additional observation over time, and testing with midnight cortisol measurements, the 2-day-2-mg dexamethasone suppression test, or the dexamethasone suppression-CRH stimulation test may be useful to identify true Cushing's syndrome in these patients.

Endocrinological effects of mirtazapine in healthy volunteers

Objective: Unlike other antidepressants, mirtazapine does not inhibit the reuptake of norepinephrine or serotonin (5-HT) but acts as an antagonist at presynaptic α 2-receptors and at postsynaptic 5-HT 2, 5-HT 3 and histamine H 1-receptors. In the present investigation, the influence of acute oral administration of 15-mg mirtazapine on the cortisol (COR), adrenocorticotropin (ACTH), growth hormone (GH) and prolactin (PRL) secretion was examined in 12 healthy male subjects, compared to placebo. Methods: After insertion of an intravenous catheter, both the mean arterial blood pressure (MAP) and the heart rate were recorded and blood samples were drawn 1 h prior to the administration of mirtazapine or placebo (7:00 a.m.), at time of administration (8:00 a.m.) and during 5 h thereafter in periods of 30 min. Concentrations of COR, ACTH, GH and PRL were measured in each blood sample by double antibody radioimmunoassay and chemiluminescence immunoassay methods. The area under the curve (AUC; 0–300 min after mirtazapine or placebo administration) was used as parameter for the COR, ACTH, GH and PRL response. Furthermore, the urinary free cortisol excretion (UFC) was determined beginning at 8:00 a.m. (time of administration of placebo or mirtazapine) up to 8:00 a.m. the day after. Results: Two-sided t-tests for paired samples revealed significantly lower COR AUC, ACTH AUC, UFC and PRL AUC values after 15-mg mirtazapine compared to placebo, whereas no significant differences were found with respect to GH AUC, MAP and heart rate. Conclusions: Since the acute inhibition of COR secretion in the healthy volunteers was paralleled by a simultaneous decrease of ACTH release, central mechanisms (e.g., inhibition of hypothalamic corticotropin releasing hormone (CRH) output) are suggested to be responsible for the inhibitory effects of mirtazapine on COR secretion. Our results are of particular interest in the light of the hypercortisolism observed in depressed patients and new pharmacological approaches such as CRH 1 receptor antagonists.

HPA-axis effects of nebulised fluticasone propionate compared with oral prednisolone in childhood asthma

The aim of this study was to compare the effect of 7 days nebulised fluticasone propionate (FP) with oral prednisolone on 24-h urinary-free cortisol excretion, systemic exposure and safety. This was a randomised, double-blind, double-dummy, two-way crossover study. Thirty-one children (19 male, 12 female, mean age 8 years) with stable asthma were randomly assigned to 7 days treatment with either FP NebulesTM (2×0.5 mg/2 ml bd) or prednisolone tablets once daily (2 mg/kg/day for 4 days [maximum 40 mg] followed by 1 mg/kg/day or half the original dose for 3 days [maximum 20 mg]). After a 2–4 week washout period, patients received the second treatment for 7 days, followed by a 2-week follow-up visit. The primary outcome measure was 24-h urinary-free cortisol concentrations corrected for creatinine. Nebulised FP (1 mg bd) had significantly less effect on 24-h urinary-free cortisol excretion than oral prednisolone (8.9 ng/ml for FP and 5.0 ng/ml for prednisolone, P=0.001). Systemic exposure to FP was also low. In conclusion, FP NebulesTM had significantly less effect on hypothalamic–pituitary–adrenal axis function than oral prednisolone in asthmatic children when used at doses recommended for the treatment of an acute exacerbation of asthma.

A low-dose adrenocorticotropin test reveals impaired adrenal function in cancer patients receiving megestrol acetate therapy

Megestrol acetate (MA) has glucocorticoid activity and can induce significant secondary adrenal suppression. We designed this study to determine the extent of adrenal insufficiency in cancer patients receiving MA by utilising a sensitive low-dose adrenocorticotropin (ACTH) stimulation test. Adrenal function was assessed by a low-dose (0.625 μg) ACTH (1-24) stimulation test in 30 patients receiving MA for metastatic cancer. 10 of the patients who failed this test underwent a standard (250 μg) test on another day. Adrenal function was also evaluated in 15 of the patients by measuring the excretion of free cortisol in 24-h urine samples. Peak serum cortisol levels following stimulation with low-dose (0.625 μg) ACTH (1-24) were <18 μg/dl in 16 of 30 (53%) patients, of whom 9 had a basal serum cortisol level of <5 μg/dl. Five of 16 poor responders to the low-dose test showed normal stimulation with the standard (250 μg) ACTH (1-24) test. Thus, adrenal insufficiency would fail to be detected by the standard high dose test in these patients. Patients who failed the low-dose ACTH (1-24) test had lower 24-h urinary free cortisol excretion (8.7±10.3 μg/24 h) than normal responders (35±12.7 μg/24 h). Impaired adrenal function is common in cancer patients receiving MA. The low-dose ACTH (1-24) test is apparently capable of revealing adrenal insufficiency undetected by the standard high-dose ACTH test. Patients receiving MA might have inadequate adrenal function during episodes of infection or after withdrawal of MA therapy and this may require prompt corticosteroid treatment.