The effects of opioid blockade and GnRH administration upon luteinizing hormone secretion in patients with anorexia nervosa during the stages of weight loss and weight recovery

Premenarchal anorexia nervosa: clinical features, psychopharmacological interventions, and rehospitalization analysis in a 1-year follow-up, controlled study

Premenarchal anorexia nervosa (AN) represents a specific subtype of AN, defined by an onset before the menarche in females, involving unique endocrine and prognostic features. The scarce data on this condition lack case-control and follow-up studies. This is a case-control, observational, naturalistic study, involving participants with premenarchal AN (premenarchal girls presenting to the study center newly diagnosed with AN) treated with a multidisciplinary hospital intervention, compared to postmenarchal AN individuals on clinical, endocrine, psychopathological, and treatment variables. The rate of rehospitalizations on a 1-year follow-up after discharge and respective prognostic factors were assessed with a Kaplan-Meier analysis and Cox regression model. The sample included 234 AN participants (43, 18.4% with premenarchal and 191, 81.6% with postmenarchal AN). When compared to postmenarchal, premenarchal AN individuals presented with lower depressive scores (Self-Administered Psychiatric Scales for Children and Adolescents (SAFA)) (U = 1387.0, p = 0.010) and lower luteinizing hormone (LH) levels (U = 3056.0, p = 0.009) and were less frequently treated with antidepressants (X² = 5.927, p = 0.015). A significant predictive model of the risk of rehospitalization (X² = 19.192, p = 0.004) identified a higher age at admission (B = 0.522, p = 0.020) and a day-hospital (vs inpatient) treatment (B = 3957, p = 0.007) as predictive factors for rehospitalization at 1-year, independent from the menarchal status.   Conclusion: This study reports the clinical and treatment characteristics of premenarchal AN in one of the largest samples available in the current literature. Specific clinical features and prognostic factors for rehospitalization at 1-year follow-up were identified. Future studies should longitudinally investigate treatment-dependent modifications in endocrine and psychopathological measures in this population. What is Known: • Premenarchal Anorexia Nervosa (AN) is a subtype of AN characterized by its onset before menarche in females and is associated with unique endocrine and prognostic features. What is New: • Individuals with premenarchal AN may display specific clinical profiles, with lower depressive symptoms and luteinizing hormone levels than postmenarchal controls.

Effect of manganese on neural endocrine hormones in serum of welders and smelters

BACKGROUND

Although manganese (Mn)-induced neurotoxicity effects are well known among occupational Mn exposure, few reports have investigated the effects on endocrine systems among welders and smelters.

OBJECTIVE

To determine the effect of high level occupational manganese (Mn) exposure on neuropsychological parameters and hormonal status.

METHODS

We used a cross-sectional design with 52 welders, 48 smelters and 43 age-matched office workers from the same factory in China. We analyzed serum endocrine hormones level and airborne Mn concentrations. Erythrocyte and urine Mn levels were quantified using inductively-coupled plasma atomic emission spectroscopy.

RESULTS

The geometric mean of air Mn concentrations for the welders and smelters were 19.7 and 273.1 μg/m³, respectively. Mn concentrations in erythrocytes of smelters were markedly greater than those in controls and welders, but there was no difference between the erythrocytes Mn levels of Control and welders. We also found an increase of Mn levels in the urine of both welders and smelters vs. controls; Mn levels in urine of smelters were higher than in welders. Self-reported neurobehavioral symptoms were higher in welders and smelters than in controls. Finally, thyroid-stimulating hormone (TSH) levels of welders were significantly lower than in controls, whereas smelters had lower prolactin (PRL), testosterone (TST) and follicle-stimulating hormone (FSH) concentrations than either controls or welders.

CONCLUSIONS

These results show that smelters have higher Mn exposure than do welders, and that Mn levels in erythrocytes or urine can be a marker for exposure. Moreover, high level occupational Mn exposure increases adverse neurobehavioral effects, and also may disrupt endocrine systems.

Disturbances in gonadal axis in women with anorexia nervosa

Anorexia nervosa negatively affects multiple body systems including the reproductive system.

AIM

To assess the disturbances in the hypothalamic-pituitary-gonadal axis (HPG) and the relationship between the gonadotropins and body weight, duration of the disease and amenorrhea we studied 40 female anorexic patients (aged 14-31 years) with a body mass index (BMI) 15.14+/-1.80 kg/m(2) and a degree of weight loss 28.67+/-8.74%. Fifteen healthy, age-matched women with normal weight served as controls.

METHODS

We investigated the disturbances in the gonadotropin levels before and after stimulation with gonadotropin-releasing hormone (GnRH) 100 microg i.v. One week later 100 mg of clomiphene citrate (CC) was administered orally for 5 days.

RESULTS

Basal levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were significantly lower in the patients. The responses of LH to GnRH were diminished, but those of FSH were exaggerated. However, after clomiphene citrate administration, LH increased 5.4 times whereas FSH increased 1.7 times. The basal levels of LH were significantly correlated with body weight (r=+0.373, p<0.05), BMI (r=+0.385, p<0.01) and percentage of the weight loss (r=-0.356, p<0.05). FSH levels were positively correlated with the duration of the disease (r=+0.481, p<0.01) and amenorrhea (r=+0.540, p<0.01).

CONCLUSIONS

Our study demonstrates dissociation in the secretion of gonadotropins after hypothalamic stimulation in anorexic patients. It also reveals the relationship between alterations in the hormones of the HPG axis, not only with the changes in body weight, but also with the duration of the disease.

Understanding women's journey of recovering from anorexia nervosa

Previous studies of recovery from anorexia nervosa (AN) have concentrated on discrete behavioral responses of individual women. Little is understood about the subjective process of women's recovery in the context of family, community, or society. In this feminist grounded theory study, the authors explored the perceptions of 12 women who considered themselves recovered or recovering from AN. They discovered a substantive theory of self-development that explains, within the current social context, women's journey from the perilous self-soothing of devastating weight loss to the informed self-care of healthy eating and problem-solving practices. The findings provide an urgently needed explanatory framework to inform women, clinicians, and health policy makers in their prevention and recovery efforts.

Aetiology, previous menstrual function and patterns of neuro-endocrine disturbance as prognostic indicators in hypothalamic amenorrhoea

BACKGROUND

Hypothalamic amenorrhoea (HA) is a syndrome associated with infertility and osteopenia in reproductive-age women.

METHODS

To understand better the natural history of this disorder, 28 women participated in a retrospective, questionnaire-based analysis to elucidate factors associated with spontaneous recovery.

RESULTS

54% of subjects developed HA related to an eating disorder, 21% related to stress +/- weight loss, and 25% without obvious contributing factors (idiopathic). HA associated with a clear precipitant had a better prognosis than idiopathic HA (71 versus 29% recovery; P < 0.05). Reversal of the inciting factor appeared necessary but not sufficient for recovery (83% recovery if factor reversed). Normal menarche occurred in 61% of subjects, oligomenorrhoea in 32%, and primary amenorrhoea in 7%. Oligomenorrhoea and normal menarche showed a trend toward better prognosis than primary amenorrhoea (NS). Compared with controls, 46% of HA patients had decreased frequency of LH pulses, 7% decreased amplitude, 18% decreases in both frequency and amplitude, 18% absent pulses, and 11% normal-appearing pulses. Pulse pattern at baseline did not predict recovery.

CONCLUSIONS

The aetiology of HA at the time of presentation predicts subsequent recovery of menstrual function. In stress, weight loss, or eating disorder-related HA, rates of recovery exceeded 80% when precipitating factors were reversed. Idiopathic HA may represent a different disorder as recovery rates were <30%.

Hypogonadotropic hypogonadism in obese women after biliopancreatic diversion

OBJECTIVE

To evaluate a particular form of weight-related amenorrhea occurring in severely obese patients after biliopancreatic diversion, a surgical procedure designed to cause weight loss.

DESIGN

Prospective, open, controlled clinical trial.

SETTING

Department of Gynecology and Obstetrics, University of Naples "Federico II", Naples, Italy. The surgical procedures were performed in various hospitals in the Naples metropolitan area.

PATIENT(S)

Eight severely obese women (mean [+/-SD] age, 26.9+/-5.3 years) who underwent biliopancreatic diversion (group A) and eight healthy women of normal weight (mean [+/-SD] age, 25.8+/-5.6 years) (group B).

INTERVENTION(S)

Biliopancreatic diversion, hormonal evaluation, and LH pulsatility evaluation.

MAIN OUTCOME MEASURE(S)

Weight parameters, hormone levels, and LH pulsatility amplitude and frequency before surgery and at the onset of amenorrhea after surgery, and the response of LH pulsatility to the infusion of naloxone at the onset of amenorrhea.

RESULT(S)

All patients lost weight after surgery and became amenorrheic after 3 months, when they had lost 25% of their basal weight but were still obese. The hormonal picture at that time was one of hypothalamic amenorrhea with significantly reduced LH pulsatility frequency and amplitude. The alterations in LH pulsatility were not modified by naloxone infusion.

CONCLUSION(S)

Obese patients who undergo dramatic weight loss may be affected by hypothalamic amenorrhea when still obese. Endogenous opioid activity does not play a significant role in this kind of hypogonadotropic hypogonadism.

A review of endocrine changes in anorexia nervosa

Anorexia nervosa is a syndrome of unknown etiology. It is associated with multiple endocrine abnormalities. Hypothalamic monoamines (especially serotonin), neuropeptides (especially neuropeptide Y and cholecystokinin) and leptin are involved in the regulation of human appetite, and in several ways they are changed in anorexia nervosa. However, it remains to be clarified whether the altered appetite regulation is secondary or etiologic. Increased secretion of corticotropin-releasing hormone and proopiomelanocortin seems to be secondary to starvation, however, there is evidence that it may maintain and intensify anorexia, excessive physical activity and amenorrhea. Hypothalamic amenorrhea, which is a diagnostic criterion in anorexia nervosa, is not solely related to the low body weight and exercise. Growth hormone resistance with low production of insulin-like growth factor I and high growth hormone secretion reflect the nutritional deprivation. The nutritional therapy of patients with anorexia nervosa might be improved by administering an anabolic agent such as growth hormone or insulin-like growth factor I. So far none of the endocrine abnormalities have proved to be primary, however, there is increasing evidence that some of these might participate in a vicious circle.

The role of the central nervous system in the psychoneuroendocrine disturbances of anorexia and bulimia nervosa

It has been well-recognized that starvation in anorexia and bulimia nervosa causes endocrine disturbances. Such disturbances may help understand why many people with eating disorders cannot easily reverse their illness since people with eating disorders often enter a downward spiraling circle with malnutrition sustaining and perpetuating the desire for more weight loss and dieting. Symptoms, such as obsessions and dysphoric mood, and altered appetitive behavior, may be exaggerated by neuropeptide alterations and thus contribute to this downward spiral. While neuropeptide disturbances do not appear to be a permanent feature or cause or anorexia nervosa, these disturbances are strongly entrenched, and are not easily corrected by improved nutrition or short-term weight normalization. This suggests that therapy should be sustained for months after nutritional normalization.

High-dose naloxone (1.0 mg/kg): psychological and endocrine effects in normal male subjects pretreated with one milligram of dexamethasone

The possible participation of the endogenous opioid system (EOS) in the negative feedback of the hypothalamic-pituitary-adrenal axis (HPA-a) activated by low doses (1 mg) of dexamethasone (Dex) was investigated. Ten male healthy subjects (mean age 31.5 +/- 1.9 SEM) were studied on 2 separate days, in a double-blind, cross-over and placebo-controlled design. All subjects were pretreated with 1.0 mg Dex orally the night (2300 h) before both test days. On the study days, subjects were admitted at 0700 h for cannula insertion; the administration of an i.v. bolus of either naloxone (Nal) (1.0 mg/kg) or saline solution (Sal) i.v. was started at 0900 h. Before and following each infusion, mood was measured by a Visual Analogue Scales (VAS) and by the Affective Quality Scale (AQS) every 30 min and blood samples were taken at 15-min intervals. Blood pressure and heart rate were also monitored. Before Dex administration, plasma cortisol levels were within the normal range in all subjects (210.4 +/- 13 ng/ml), while after 9 h after Dex cortisol levels showed the expected significant (p < 0.01) decrease (11.5 +/- 1.9 and 15.04 +/- 0.7 ng/ml for Sal and Nal test days respectively). There were no detectable increases in plasma cortisol levels following either Nal nor Sal administration. However, there was a Nal-induced significant increase in LH (p < 0.01) thus indicating that an effective opioid blockade at the level of the hypothalamic-pituitary unit occurred. There were also a mild and selective Dex + Nal-induced dysphoric (mood factors related to subjects perception of their cognition) and bradycardic effects (p < 0.05). These results suggest that the EOS is not directly involved in the negative feedback triggered by low doses of Dex of the HPA-a, and that there might be a possible glucocorticoid-opioid interaction for the modulation of some aspects of mood.

Acute dopaminergic blockade augments the naloxone-induced LH rise in estrogen-treated postmenopausal women

OBJECTIVES

To assess the effect of estrogen replacement on the simultaneous blockade of the dopaminergic (DA) and opioidergic neural control of hypothalamic-gonadotropic function in postmenopausal women.

METHODS

Twenty healthy postmenopausal women, 48-55 years old were randomly assigned to receive either a 4-h naloxone infusion at 2 mg/h (group 1, n = 7) or a 10 mg i.v. bolus of metoclopramide (group 2, n = 7) or both drugs, simultaneously (group 3, n = 6) before and after 3 weeks of transdermal estradiol (100 microg/day). Blood samples were obtained at 30-min intervals during 4 h and duplicate determinations of serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2) and prolactin (PRL) were performed in all samples.

RESULTS

In group 1 only a mild but significant LH rise after but not before estrogen replacement was seen. In group 2 PRL had a greater rise after than before estrogen therapy, without other hormonal changes. In group 3 a greater rise in PRL occurred after than before estrogen administration and serum LH had a sustained rise throughout the test only after estrogen replacement (greater than in group 1). No FSH changes were observed. The after-estradiol PRL response was nearly similar in groups 2 and 3.

CONCLUSIONS

Our results indicate that in the untreated postmenopausal women, the dopaminergic system has little and the opioidergic system has no significant input in the control of gonadotropin or prolactin release. However, following estrogen replacement, opioids are involved in the inhibition of LH release and stimulating PRL release, while the dopaminergic system acts to inhibit PRL release and modulates LH release or inhibition, depending on the levels of circulating estrogens.

Neuropeptide abnormalities in anorexia nervosa

Starvation-induced alterations of neuropeptide activity probably contribute to neuroendocrine dysfunctions in anorexia nervosa. For example, CRH alterations contribute to hypercortisolemia and NPY alterations may contribute to amenorrhea. Alterations of these peptides as well as opioids, vasopressin, and oxytocin activity could contribute to other characteristic psychophysiological disturbances, such as reduced feeding, in acutely ill anorexics. Such neuropeptide disturbances could contribute to the vicious cycle that has been hypothesized to occur in anorexia nervosa. That is, the consequences of malnutrition perpetuate pathological behavior.

Evidence for an altered luteinizing hormone sensitivity to naloxone in pathological hyperprolactinaemia

OBJECTIVE

The underlying mechanisms involved in the pathogenesis of amenorrhoea in hyperprolactinaemic states still remain unclear. Conflicting information exists on the role of endogenous opiates on gonadotrophin disturbances in this pathological condition. In this study we have undertaken a detailed investigation of LH and PRL secretion before and during administration of naloxone, an opioid receptor blocker, in hyperprolactinaemic women with or without ovarian function in order to assess the role of ovarian steroids upon naloxone induced LH and PRL release.

DESIGN

Five anovulatory and six ovulatory subjects with hyperprolactinaemia were studied before and during naloxone infusion. Five normo-prolactinaemic ovulatory subjects were included as controls. All ovulatory subjects were studied during the luteal phase of a menstrual cycle. Blood was sampled every 10-20 minutes over a 16-hour period on two alternate days. On study day 1 (control day), subjects received two sets of saline infusion every 6 hours and one saline bolus at the beginning of the seventh hour; on study day 3 (naloxone day), they received a saline infusion during the first 6 hours, an intravenous bolus of naloxone (20 mg) at the beginning of the seventh hour and then a continuous naloxone infusion (1.6 mg/hour) during the ensuing 6 hours. Pituitary LH responsiveness and reserve were assessed on both study days by the subsequent administration of 5 and 95 micrograms of GnRH 4 hours before the completion of each sampling period.

MEASUREMENTS

Serum concentrations of LH, PRL, oestradiol and progesterone were determined by radioimmunoassay. LH and PRL pulse detection and characteristics were analysed by the Cluster program.

RESULTS

Serum PRL levels in hyperprolactinaemic anovulatory and ovulatory subjects were significantly elevated above the normal range. Oestradiol and progesterone serum levels during the luteal phase in women with hyperprolactinaemia and regular menses were similar to those in control ovulatory subjects. Mean LH concentrations increased during naloxone infusion (P < 0.05) in ovulatory hyperprolactinaemia and controls, whereas PRL increased (P < 0.05) only in the group of control subjects. LH pulse amplitude and pulse interval were increased by naloxone (P < 0.05) in all the ovulatory subjects, with no significant changes in anovulatory hyperprolactinaemic women. PRL pulse characteristics were modified significantly by naloxone only in the control group. On day 1, GnRH administration increased LH in all groups, whereas a consistently lower pituitary LH response was observed after naloxone (day 3). Serum PRL levels significantly increased after GnRH administration on day 1 only in normal women, whilst on day 3 this GnRH-dependent PRL releasing effect was significantly attenuated.

CONCLUSIONS

The absence of stimulatory effects of naloxone on LH in anovulatory hyperprolactinaemia implies that endogenous opiates do not play a significant role in the mechanisms governing hypothalamic amenorrhoea in this syndrome. The results in subjects with ovulatory hyperprolactinaemia suggest the existence of an active role of ovarian steroids on naloxone induced LH release. These data, along with those previously reported in normal women throughout the menstrual cycle, are consistent with the concept that sex steroid hormones contribute to the underlying mechanisms involved in the opioidergic control of LH and PRL release. Whether PRL by itself or through other non-opioid neuroendocrine pathways alters the hypothalamic-gonadotroph unit still requires further investigation.

Endogenous opiates: 1992

This paper is the fifteenth installment of our annual review of research concerning the opiate system. It includes papers published during 1992 involving the behavioral, non-analgesic, effects of the endogenous opiate peptides. The specific topics this year include stress; tolerance and dependence; eating; drinking; gastrointestinal and renal function; mental illness and mood; learning, memory, and reward; cardiovascular responses; respiration and thermoregulation; seizures and other neurological disorders; electrical-related activity; general activity and locomotion; sex, pregnancy, and development; immunological responses; and other behaviors.