ABSTRACT: Anorexia nervosa is characterized by self-induced starvation and associated with severe bone and fat loss. Oxytocin is a peptide hormone involved in appetite and energy homeostasis. Recent data show that oxytocin has an anabolic effect on bone and stimulates osteoblast function. There is limited information about oxytocin levels or their relationship to decreased bone mineral density in anorexia nervosa. Our objective was to investigate the relationship between oxytocin levels, bone mineral density, and body composition in women with anorexia nervosa.
We studied 36 women, mean ± SEM age 27.6 ± 1.3 years: 17 with DSM-IV anorexia nervosa and 19 healthy controls in a cross-sectional study. Oxytocin levels were determined from pooled serum samples obtained every 20 minutes from 8 pm to 8 am during an inpatient overnight visit. Fasting leptin levels were measured. Bone mineral density at the anterior-posterior and lateral spine and hip and body composition were assessed by dual energy x-ray absorptiometry. The study was conducted from September 2004 to June 2008.
Subjects with anorexia nervosa versus healthy controls had lower mean ± SEM oxytocin levels (14.3 ± 1.5 vs 31.8 ± 5.1 pg/mL, P = .003), leptin levels (2.7 ± 0.5 vs 11.4 ± 1.1 ng/mL, P < .0001), bone mineral density (anterior-posterior spine: 0.83 ± 0.02 vs 1.04 ± 0.03; lateral spine: 0.63 ± 0.02 vs 0.81 ± 0.02; total hip: 0.79 ± 0.03 vs 0.97 ± 0.03 g/cm², P < .0001), and fat mass (8.8 ± 0.6 vs 19.7 ± 0.9 kg, P < .0001). Oxytocin levels were associated with bone mineral density at the anterior-posterior (r = 0.40, P = .02) and lateral (r = 0.36, P = .04) spine, fat mass (r = 0.42, P = .01), and leptin levels (r = 0.55, P = .001).
Overnight secretion of oxytocin in women with anorexia nervosa is decreased compared with healthy women. Low oxytocin levels are associated with decreased bone mineral density and body fat and may contribute to anorexia nervosa-induced bone loss.
The Journal of Clinical Psychiatry 08/2011; 72(11):1546-51. · 5.80 Impact Factor
ABSTRACT: Anorexia nervosa (AN), a state of chronic nutritional deprivation, is characterized by GH resistance with elevated GH levels and decreased levels of IGF-I. The effects of supraphysiological recombinant human GH (rhGH) on GH resistance in AN are not currently known.
The aim was to investigate whether supraphysiological rhGH increases IGF-I levels in AN.
We conducted a randomized, placebo-controlled study in a Clinical Research Center.
We studied 21 women with AN, 10 (mean age, 28 ± 2.1 yr) treated with rhGH and 11 (mean age, 29.2 ± 2.6 yr) treated with placebo.
rhGH (mean maximum daily dose, 1.4 ± 0.12 mg/d) or placebo was administered to patients for 12 wk.
IGF-I, N-terminal propeptide of type 1 procollagen, type I collagen C-telopeptide, glucose, and insulin levels were measured at wk 0, 1, 2, 3, 4, 8, and 12; C-terminal propeptide of type 1 procollagen, leptin, and free fatty acid levels were measured at wk 0 and 12. Body composition, including total fat and lean mass, was measured by dual-energy x-ray absorptiometry at wk 0 and 12.
IGF-I levels did not differ between the groups at baseline or after treatment (median after 12 wk-rhGH, 124 ng/ml, interquartile range, 94.5, 170.3; vs. placebo, 85.5 ng/ml, interquartile range, 62, 139; P = 0.3). Similarly, changes in glucose, insulin, free fatty acids, and bone markers did not differ between the groups. Total fat mass and percentage fat mass (rhGH, -2.5 ± 0.6%, vs. placebo, 2.2 ± 1.1%; P = 0.004) decreased significantly in the rhGH group compared to placebo despite comparable weight.
Supraphysiological rhGH administration decreases fat mass in AN without increasing IGF-I levels, supporting the role of GH as a mediator of lipolysis independent of IGF-I.
The Journal of clinical endocrinology and metabolism 11/2010; 95(11):4889-97. · 6.50 Impact Factor
ABSTRACT: The ability of combined dexamethasone-corticotropin releasing hormone (Dex-CRH) testing to distinguish pseudo-Cushing's syndrome (PCS) from Cushing's syndrome is controversial. One factor potentially impairing diagnostic efficacy is the concomitant use of commonly prescribed medications that may alter dexamethasone metabolism.
Our objective was to assess the diagnostic accuracy of the Dex-CRH test and evaluate the potential impact of concomitant drugs.
The study was a retrospective one.
Participants included 101 patients [60 Cushing's disease (CD); 41 PCS] who underwent 112 Dex-CRH tests. Patients were divided into two groups, depending on use of medications potentially interfering with dexamethasone metabolism: 58 tests were classified as No Meds (32 CD; 26 PCS) and 54 as Meds (34 CD; 20 PCS). The latter group was further subdivided into patients taking one medication vs. those taking multiple medications.
Diagnostic accuracy of different serum cortisol and ACTH thresholds at baseline and 15 min after CRH injection was assessed.
The specificity of a baseline post-low-dose-dexamethasone-suppressed test cortisol lower than 1.4 microg/dl (38 nmol/liter) was significantly higher in the No Meds vs. the Meds group (P = 0.014). Sensitivity and specificity using a post-CRH cortisol cutoff of 1.4 microg/dl (38 nmol/liter) were 93.1% (95% confidence interval = 88.4-97.8) and 92.3% (95% confidence interval = 87-97.6) in the No Meds group. The specificity of a cortisol lower than 1.4 microg/dl (38 nmol/l) at 15 min after CRH was significantly higher in patients taking only one medication vs. those on multidrug treatment (P < 0.05).
Medications commonly prescribed in hypercortisolemic patients undergoing Dex-CRH testing may contribute to the variable diagnostic accuracy of this test. Prospective studies to address this issue are needed.
The Journal of clinical endocrinology and metabolism 10/2009; 94(12):4851-9. · 6.50 Impact Factor