Dopamine agonists (DAs) represent a cornerstone in the management of patients with hyperprolactinemia and have an important role in the treatment of neurologic disorders, including Parkinson’s disease and restless legs syndrome. A growing body of evidence has identified impulse control disorders (ICDs) as possible adverse effects of DA therapy. A variety of ICDs may occur in patients treated with DA, including compulsive shopping, pathologic gambling, stealing, hypersexuality and punding (repetitive performance of tasks, such as collecting, sorting, disassembling and assembling objects). These behaviors can have devastating effects on patients’ life and family. In the present review article, we summarize available data on ICDs in patients with hyperprolactinemia as well as other disorders. Possible risk factors for the emergence of ICDs in patients treated with DA are discussed and the putative pathophysiologic mechanisms underlying the development of ICDs in this setting are reviewed. In addition, strategies for the early identification and management of ICDs in patients on DA are discussed. In conclusion, a wide variety of ICDs can occur in patients treated with DA, including those with hyperprolactinemia. The development of ICDs can have serious implications for patients’ well-being and family. Endocrinologists and other physicians involved in the care of patients on DA therapy must be aware of this potential adverse effect, counsel patients regarding pertinent symptoms and regularly evaluate treated patients for the development of ICDs. Early detection of ICDs and discontinuation of DA therapy can mitigate the potential harms associated with ICDs in these patients.
Maya Barake, Anne Klibanski and Nicholas A Tritos
Elizabeth A Lawson, Laura M Holsen, Rebecca DeSanti, McKale Santin, Erinne Meenaghan, David B Herzog, Jill M Goldstein and Anne Klibanski
Corticotrophin-releasing hormone (CRH)-mediated hypercortisolemia has been demonstrated in anorexia nervosa (AN), a psychiatric disorder characterized by food restriction despite low body weight. While CRH is anorexigenic, downstream cortisol stimulates hunger. Using a food-related functional magnetic resonance imaging (fMRI) paradigm, we have demonstrated hypoactivation of brain regions involved in food motivation in women with AN, even after weight recovery. The relationship between hypothalamic–pituitary–adrenal (HPA) axis dysregulation and appetite and the association with food-motivation neurocircuitry hypoactivation are unknown in AN. We investigated the relationship between HPA activity, appetite, and food-motivation neurocircuitry hypoactivation in AN.
Cross-sectional study of 36 women (13 AN, ten weight-recovered AN (ANWR), and 13 healthy controls (HC)).
Peripheral cortisol and ACTH levels were measured in a fasting state and 30, 60, and 120 min after a standardized mixed meal. The visual analog scale was used to assess homeostatic and hedonic appetite. fMRI was performed during visual processing of food and non-food stimuli to measure the brain activation pre- and post-meal.
In each group, serum cortisol levels decreased following the meal. Mean fasting, 120 min post-meal, and nadir cortisol levels were high in AN vs HC. Mean postprandial ACTH levels were high in ANWR compared with HC and AN subjects. Cortisol levels were associated with lower fasting homeostatic and hedonic appetite, independent of BMI and depressive symptoms. Cortisol levels were also associated with between-group variance in activation in the food-motivation brain regions (e.g. hypothalamus, amygdala, hippocampus, orbitofrontal cortex, and insula).
HPA activation may contribute to the maintenance of AN by the suppression of appetitive drive.
Nicholas A Tritos, Philippe Chanson, Camilo Jimenez, Donna King, Peter J Jönsson, Anne Klibanski and Beverly M K Biller
To examine the effectiveness and safety of primary pegvisomant monotherapy.
Retrospective analysis of data extracted from ACROSTUDY (global observational outcomes study of patients with acromegaly treated with pegvisomant).
The earliest time to insulin-like growth factor 1 (IGF-1) normalization on pegvisomant monotherapy was determined. Both the proportion of patients who achieved IGF-1 normalization and the time to IGF-1 normalization on pegvisomant monotherapy were assessed.
Eligible patients included 28 subjects on primary medical therapy (PT) and 176 controls on adjunctive pegvisomant therapy treated postoperatively, including 43 who were naïve to medical therapy (NMT) and 133 who were previously treated medically and were washed out (WASH). IGF-1 normalization occurred in 76.9% (PT), 85.2% (NMT) and 78.3% (WASH) patients (P = NS). Median times to IGF-1 normalization were 0.5 year (PT), 0.7 year (NMT) and 0.6 year (WASH), P = NS. On survival analysis, the fraction of patients controlled on pegvisomant monotherapy was not different between groups. Higher baseline IGF-1 levels, obtained at study entry, predicted a lower likelihood of IGF-1 normalization on monotherapy (P = 0.012). Safety data include low prevalence of skin rashes, injection site reactions and reversible transaminase elevations. There was one patient (NMT) with a verified increase in tumor size.
Pegvisomant monotherapy, administered either as primary medical therapy or as adjunctive therapy according to local practice, led to IGF-1 normalization in >75% of patients. Pegvisomant monotherapy had a favorable safety profile, consistent with previous observations. Prospective data are needed to further evaluate the role of primary pegvisomant monotherapy in acromegaly.
Brandon P Galm, E Leonardo Martinez-Salazar, Brooke Swearingen, Martin Torriani, Anne Klibanski, Miriam A Bredella and Nicholas A Tritos
There are limited predictors of prognosis in patients with clinically non-functioning pituitary adenomas (NFPAs). We hypothesized that MRI texture analysis may predict tumor recurrence or progression in patients with NFPAs undergoing transsphenoidal pituitary surgery (TSS).
To characterize texture parameters on preoperative MRI examinations in patients with NFPAs in relation to prognosis.
Retrospective study of patients with NFPAs who underwent TSS at our institution between 2009 and 2010. Clinical, radiological and histopathological data were extracted from electronic medical records. MRI texture analysis was performed on coronal T1-weighted non-enhanced MR images using ImageJ (NIH). MRI texture parameters were used to predict tumor recurrence or progression. Both logistic regression and Cox proportional hazard analyses were conducted to adjust for potential confounders.
Data on 78 patients were analyzed. On both crude and multivariable-adjusted analyses, mean, median, mode, minimum and maximum pixel intensity were associated with the risk of pituitary tumor recurrence or progression after TSS. Patients whose tumor mean pixel intensity was above the median for the population had a hazard ratio of 0.44 (95% CI: 0.21–0.94, P = 0.034) for recurrence or progression in comparison with tumors below the median.
Our data suggest that MRI texture analysis can predict the risk of tumor recurrence or progression in patients with NFPAs.
Pouneh K Fazeli, Alex Faje, Miriam A Bredella, Sai Polineni, Stephen Russell, Megi Resulaj, Clifford J. Rosen and Anne Klibanski
Objective: In anorexia nervosa, a psychiatric disease characterized by self-induced starvation and a model of chronic undernutrition, levels of subcutaneous (SAT) and visceral (VAT) adipose tissue are low, whereas marrow adipose tissue (MAT) levels are elevated compared to normal-weight women. The reason for this paradoxical elevation of an adipose tissue depot in starvation is not known. We sought to understand changes in MAT in response to sub-acute changes in weight and to compare these changes with those of other fat depots and body composition parameters.
Design and Methods: We conducted a 12-month longitudinal study including 46 premenopausal women (n=26 with anorexia nervosa and n=20 normal-weight controls) with a mean (SEM) age of 28.2+/-0.8 years. We measured MAT, SAT, VAT, and bone mineral density (BMD) at baseline and after 12 months.
Results: At baseline, SAT (p<0.0001), VAT (p<0.02) and BMD of the spine and hip (p<0.0002) were significantly lower and vertebral and metaphyseal MAT (p<0.001) significantly higher in anorexia nervosa compared to controls. Weight gain over 12 months was associated with increases not only in SAT and VAT, but also epiphyseal MAT (p<0.03). Changes in epiphyseal MAT were positively associated with changes in BMD (p<0.02).
Conclusions: In contrast to the steady-state, in which MAT levels are higher in anorexia nervosa and MAT and BMD are inversely associated, short-term weight gain is associated with increases in both MAT and BMD. These longitudinal data demonstrate the dynamic nature of this fat depot and provide further evidence of its possible role in mineral metabolism.
Elizabeth A Lawson, Kamryn T Eddy, Daniel Donoho, Madhusmita Misra, Karen K Miller, Erinne Meenaghan, Janet Lydecker, David Herzog and Anne Klibanski
Disordered eating occurs in women at both weight extremes of anorexia nervosa (AN) and obesity. Cortisol, peptide YY (PYY), leptin, and ghrelin are hormones involved in appetite and feeding behavior that vary with weight and body fat. Abnormal levels of these hormones have been reported in women with AN, functional hypothalamic amenorrhea (HA), and obesity. The relationship between appetite-regulating hormones and disordered eating psychopathology is unknown. We therefore studied the relationship between orexigenic and anorexigenic hormones and disordered eating psychopathology in women across a range of weights.
A cross-sectional study of 65 women, 18–45 years: 16 with AN, 12 normal-weight with HA, 17 overweight or obese, and 20 normal-weight in good health.
Two validated measures of disordered eating psychopathology, the Eating Disorders Examination-Questionnaire (EDE-Q) and Eating Disorders Inventory-2 (EDI-2), were administered. Fasting PYY, leptin, and ghrelin levels were measured; cortisol levels were pooled from serum samples obtained every 20 min from 2000 to 0800 h.
Cortisol and PYY levels were positively associated with disordered eating psychopathology including restraint, eating concerns, and body image disturbance, independent of body mass index (BMI). Although leptin levels were negatively associated with disordered eating psychopathology, these relationships were not significant after controlling for BMI. Ghrelin levels were generally not associated with EDE-Q or EDI-2 scores.
Higher levels of cortisol and PYY are associated with disordered eating psychopathology independent of BMI in women across the weight spectrum, suggesting that abnormalities in appetite regulation may be associated with specific eating disorder pathologies.
Elizabeth A Lawson, Kathryn E Ackerman, Nara Mendes Estella, Gabriela Guereca, Lisa Pierce, Patrick M Sluss, Mary L Bouxsein, Anne Klibanski and Madhusmita Misra
Preclinical data indicate that oxytocin, a hormone produced in the hypothalamus and secreted into the peripheral circulation, is anabolic to bone. Oxytocin knockout mice have severe osteoporosis, and administration of oxytocin improves bone microarchitecture in these mice. Data suggest that exercise may modify oxytocin secretion, but this has not been studied in athletes in relation to bone. We therefore investigated oxytocin secretion and its association with bone microarchitecture and strength in young female athletes.
Cross-sectional study of 45 females, 14–21 years (15 amenorrheic athletes (AA), 15 eumenorrheic athletes (EA), and 15 nonathletes (NA)), of comparable bone age and BMI.
We used high-resolution peripheral quantitative CT to assess bone microarchitecture and finite element analysis to estimate bone strength at the weight-bearing distal tibia and non-weight-bearing ultradistal radius. Serum samples were obtained every 60 min, 2300–0700 h, and pooled for an integrated measure of nocturnal oxytocin secretion. Midnight and 0700 h samples were used to assess diurnal variation of oxytocin.
Nocturnal oxytocin levels were lower in AA and EA than in NA. After controlling for estradiol, the difference in nocturnal oxytocin between AA and NA remained significant. Midnight and 0700 h oxytocin levels did not differ between groups. At the tibia and radius, AA had impaired microarchitecture compared with NA. In AA, nocturnal oxytocin correlated strongly with trabecular and cortical microarchitecture, particularly at the non-weight-bearing radius. In regression models that include known predictors of microarchitecture in AA, oxytocin accounted for a substantial portion of the variability in microarchitectural and strength parameters.
Nocturnal oxytocin secretion is low in AA compared with NA and associated with site-dependent microarchitectural parameters. Oxytocin may contribute to hypoestrogenemic bone loss in AA.
Paula P B Silva, Fatemeh G Amlashi, Elaine W Yu, Karen J Pulaski-Liebert, Anu V Gerweck, Pouneh K Fazeli, Elizabeth Lawson, Lisa B Nachtigall, Beverly M K Biller, Karen K Miller, Anne Klibanski, Mary Bouxsein and Nicholas A Tritos
Both acromegaly and adult growth hormone deficiency (GHD) are associated with increased fracture risk. Sufficient data are lacking regarding cortical bone microarchitecture and bone strength, as assessed by microfinite element analysis (µFEA).
To elucidate both cortical and trabecular bone microarchitecture and estimated bone strength in men with active acromegaly or GHD compared to healthy controls.
Design and subjects
Cross-sectional study at a clinical research center, including 48 men (16 with acromegaly, 16 with GHD and 16 healthy controls).
Areal bone mineral density (aBMD), cortical and trabecular bone microarchitecture and estimated bone strength (µFEA) at the radius and tibia.
aBMD was not different between the 3 groups at any skeletal site. At the radius, patients with acromegaly had greater cortical area (P < 0.0001), cortical thickness (P = 0.0038), cortical pore volume (P < 0.0001) and cortical porosity (P = 0.0008), but lower trabecular bone density (P = 0.0010) compared to controls. At the tibia, patients with acromegaly had lower trabecular bone density (P = 0.0082), but no differences in cortical bone microstructure. Compressive strength and failure load did not significantly differ between groups. These findings persisted after excluding patients with hypogonadism. Bone microarchitecture was not deficient in patients with GHD.
Both cortical and trabecular microarchitecture are altered in men with acromegaly. Our data indicate that GH excess is associated with distinct effects in cortical vs trabecular bone compartments. Our observations also affirm the limitations of aBMD testing in the evaluation of patients with acromegaly.