Age-related differences in hormonal and nutritional impact on lean anorexia nervosa bone turnover uncoupling

A scoping review of circulating peptides assessments in anorexia nervosa: Uncovering diversity and nuanced findings

Understanding biological mechanisms underlying anorexia nervosa (AN) is necessary to develop care strategies. Despite many articles dedicated to peptides assessment in AN, there is no systematic review. A scoping review of circulating peptides published in relation to AN, comparing their results with those of controls, was conducted. Embase and PubMed databases were search from 1966 to 2022 (PROSPERO CRD42022323716). All original English articles, assessing peptides in AN (except classical markers) were analyzed. 1151 studies for 207 peptides, in 486 published articles were selected, and evidences/trends in AN were compared to controls. Fifteen clusters of function gathering peptides covering physiopathological aspects of AN were identified. This scoping review revealed a large variety of circulating peptides explored in AN. Some peptides presented with convincing results and helped understanding pathophysiologic aspects. Other peptides presented with nuanced results, partly due to insufficient number of studies, multiple assay techniques, inadequate sampling time, and lack of phenotyping. Conversion from bench-to-bed remains difficult and may explain why peptides evaluations did not currently lead to specific international recommendations or tailored therapeutic/preventive strategies. Peptide evaluation in anorexia nervosa could explore secretion profiles, and test it in well-phenotyped patients with AN, to conclude for potential clinical use, and finally design therapeutic tests.

Older adult women with chronic anorexia nervosa: heterogeneous adaptation to undernutrition over time

INTRODUCTION

Anorexia nervosa (AN) in older adult women is primarily described through reviews or case reports focusing on psychiatric traits, with no comprehensive studies evaluating their complete nutritional and hormonal profiles. This study aimed to describe a group of women with anorexia nervosa aged above 35 years old (AN35), and compare them with young women with anorexia nervosa (ANY) and normal-weight control participants.

METHOD

Anthropometric, metabolic, nutritional, and psychiatric parameters were collected and compared among three groups of women: 50 AN35, 37 ANY, and 38 controls.

RESULTS

AN35 exhibited a mean disease duration of 271 ± 19 months, with 94% chronic forms and 58% restrictive types. Despite having similar BMI as ANY, AN35 displayed more altered parameters, including higher liver enzymes (p = 0.007), free T3 (p = 0.0046) and leptin (p < 0.0001); and lower albumin (p = 0.0029), and white cells (p < 0.0001). AN35 showed significant heterogeneity in hormonal adaptation, such as free T3. Half of the patients aged above 51 years revealed high gonadotropin levels despite being undernourished. Additionally, AN35 groups presented with 50% of bones fractures, decreased T-scores under -2.5 (p < 0.0001 for femoral), and altered micro architectural HRPQT parameters compared to ANY.

CONCLUSION

Anorexia nervosa in older adult women is predominantly chronic. Nutritional parameters changes with age suggests a significant heterogeneity and possible adaptation of energy balance and bodyweight set point for others. Complications may be severe, altering the quality of life, and sometimes potentially lethal. These findings highlight the potential adaptation of energy balance with age, and should assist clinicians in clinical practice.

Structure-function relationship of the pituitary gland in anorexia nervosa and intense physical activity

Patients with Anorexia Nervosa (AN) and athletes share intense physical activity and pituitary hormonal disturbances related to absolute (AN) or relative (athletes) undernutrition. Pituitary gland (PG) structure evaluations in those conditions are scarce, and did not differentiate anterior from posterior lobe. We evaluated the structure-function relationship of anterior and posterior PG in AN and athletes, and potential reversibility of this alteration in a group of weight-recovered patients (AN_Rec). Manual delineation of anterior (AP) and posterior (PP) PG was performed on T1-weighted MR images in 17 women with AN, 15 women with AN_Rec, 18 athletes women and 25 female controls. Anthropometric, hormonal, and psychometric parameters were explored and correlated with PG volumes. AP volume (APV) was lower in AN (448 ± 82 mm3), AN_Rec (505 ± 59 mm3), and athletes (540 ± 101 mm3) vs. Controls (615 ± 61 mm3, p < 0.00001, p < 0.00001 and p = 0.02, respectively); and smaller in AN vs. AN_Rec (p = 0.007). PP volume did not show any differences between the groups. APV was positively correlated with weight (R = 0.36, p = 0.011) in AN, and luteinizing hormone (R = 0.35, p = 0.014) in total group. In AN, mean growth hormone (GH) was negatively correlated with global pituitary volume (R = 0.31, p = 0.031) and APV (R = 0.29, p = 0.037). Absolute and relative undernutrition led to a decreased anterior pituitary gland volume, which was reversible with weight gain, correlated with low bodyweight, and blockade of gonadal hypothalamic-pituitary axis. Intriguing inverse correlation between anterior pituitary gland volume and GH plasma level could suggests a low storage capacity of anterior pituitary gland and increased reactivity to low insulin-like growth factor type 1.

Mechanisms and predictors of menses resumption once normal weight is reached in anorexia nervosa

BACKGROUND

In cases of Anorexia Nervosa (AN), achieving weight gain recovery beyond the lower limits set by the World Health Organization and normalizing classical nutritional markers appears to be essential for most patients. However, this is not always adequate to restore menstrual cycles. This discrepancy can cause concern for both patients and healthcare providers, and can impact the medical management of these individuals. Thus, the purpose of this study was to assess the ability of anthropometric and hormonal factors to predict the resumption of menstrual cycles in individuals with anorexia nervosa upon reaching a normal body weight.

METHOD

Patients with AN who had achieved a normal Body Mass Index but had not yet resumed their menstrual cycles (referred to as ANRec) were evaluated on two occasions: first at visit 1 and then again 6 months later, provided their body weight remained stable over this period (visit 2). Among the 46 ANRec patients who reached visit 2, they were categorized into two groups: 20 with persistent amenorrhea (PA-ANRec) and 26 who had regained their menstrual cycles (RM-ANRec). Anthropometric measurements, several hormone levels, Luteinizing Hormone (LH) pulsatility over a 4-h period, and LH response to gonadotropin-releasing hormone injection (LH/GnRH) were then compared between the two groups at visit 1.

RESULTS

Patients in the RM-ANRec group exhibited higher levels of follicular stimulating hormone, estradiol, inhibin B, LH/GnRH, and lower levels of ghrelin compared to those in the PA-ANRec group. Analysis of Receiver Operating Characteristic curves indicated that having ≥ 2 LH pulses over a 4-h period, LH/GnRH levels ≥ 33 IU/l, and inhibin B levels > 63 pg/ml predicted the resumption of menstrual cycles with a high degree of specificity (87%, 100%, and 100%, respectively) and sensitivity (82%, 80%, and 79%, respectively).

CONCLUSIONS

These three hormonal tests, of which two are straightforward to perform, demonstrated a high predictive accuracy for the resumption of menstrual cycles. They could offer valuable support for the management of individuals with AN upon achieving normalized weight. Negative results from these tests could assist clinicians and patients in maintaining their efforts to attain individualized metabolic targets.

TRIAL REGISTRATION

IORG0004981.

Associations between bone mineral density, body composition and amenorrhoea in females with eating disorders: a systematic review and meta-analysis

BACKGROUND

Lower bone mineral density (BMD) increases the risk of osteoporosis in individuals with eating disorders (EDs), particularly women with anorexia nervosa (AN), making them susceptible to pain and fractures throughout adulthood. In AN, low weight, hypothalamic amenorrhoea, and longer illness duration are established risk factors for low BMD, and in people with other EDs a history of AN seems to be an important risk factor for low BMD.

PURPOSE

To conduct a systematic review and meta-analysis of BMD in individuals with EDs, including AN, bulimia nervosa (BN), binge-eating disorder (BED) and other specified feeding or eating disorders (OSFED) compared to healthy controls (HC).

METHODS

Following PRISMA guidelines, electronic databases were reviewed and supplemented with a literature search until 2/2022 of publications measuring BMD (dual-energy X-ray absorptiometry or dual photon absorptiometry) in females with any current ED diagnosis and a HC group. Primary outcomes were spine, hip, femur and total body BMD. Explanatory variables were fat mass, lean mass and ED clinical characteristics (age, illness duration, body mass index (BMI), amenorrhoea occurrence and duration, and oral contraceptives use).

RESULTS

Forty-three studies were identified (N = 4163 women, mean age 23.4 years, min: 14.0, max: 37.4). No study with individuals with BED met the inclusion criteria. BMD in individuals with AN (total body, spine, hip, and femur), with BN (total body and spine) and with OSFED (spine) was lower than in HC. Meta-regression analyses of women with any ED (AN, BN or OSFED) (N = 2058) showed low BMI, low fat mass, low lean mass and being amenorrhoeic significantly associated with lower total body and spine BMD. In AN, only low fat mass was significantly associated with low total body BMD.

CONCLUSION

Predictors of low BMD were low BMI, low fat mass, low lean mass and amenorrhoea, but not age or illness duration. In people with EDs, body composition measurement and menstrual status, in addition to BMI, are likely to provide a more accurate assessment of individual risk to low BMD and osteoporosis.

Growth factors in anorexia nervosa: a systematic review and meta-analysis of cross-sectional and longitudinal data

OBJECTIVES

Growth factors are signalling molecules that play roles in the survival, proliferation, migration, and differentiation of cells. Studies have found alterations in specific growth factors in anorexia nervosa (AN).

METHODS

This systematic review and meta-analysis examined articles from three databases, measuring growth factors in AN cross-sectionally and longitudinally, and in recovered AN (rec-AN) cross-sectionally. Random-effects meta-analyses were conducted for brain-derived neurotrophic factor (BDNF) and insulin growth factor-I (IGF-1) for cross-sectional and longitudinal studies.

RESULTS

A total of 82 studies were included: 56 cross-sectional (BDNF: n = 15; IGF-1: n = 41) and 24 longitudinal (BDNF: n = 5; IGF-1: n = 19) were meta-analysed and 20 studies were narratively synthesised. In cross-sectional analyses, BDNF and IGF-1 were lower in AN compared to controls, and BDNF was marginally greater in rec-AN compared to controls. In longitudinal meta-analyses, BDNF and IGF-1 increased from baseline to follow-up. Cross-sectional subgroup analyses revealed no differences in BDNF between controls and AN binge-eating/purging subtypes.

CONCLUSIONS

It is likely that the low BDNF and IGF-1 levels found in AN are consequences of starvation, which are reversible with weight restoration. The increase in BDNF and IGF-1 during therapeutic weight restoration might improve neuroplasticity, which is the basis of learning, and thus psychotherapeutic success.

Dehydroepiandrosterone status and efficacy of dehydroepiandrosterone supplementation for bone health in anorexia nervosa: A systematic review and meta-analysis

OBJECTIVE

This study was designed to determine the status of dehydroepiandrosterone (DHEA) in women with anorexia nervosa (AN) and to assess the efficacy of DHEA supplementation as a treatment for bone health in women with AN.

METHOD

Studies were retrieved from the PubMed, Embase, Cochrane Library, MEDLINE, and Scopus databases from inception to February 14, 2022. Observational studies that compared serum DHEA levels between women with AN and healthy controls were included for meta-analysis, and randomized controlled trials (RCTs) that evaluated the effects of DHEA supplementation on bone mass were reviewed.

RESULTS

Meta-analysis of 15 cross-sectional studies revealed that patients with AN had significantly elevated serum DHEA levels (mean difference (MD) = 311.63 ng/dl; 95% confidence interval (CI), 78.01-545.25) and reduced DHEAS levels (MD = -24.90 μg/dl; 95% CI, -41.72 to -8.07) compared with healthy controls. A systematic review of seven RCTs found that DHEA monotherapy does not improve bone mineral density (BMD) compared with placebo after adjusting for weight gain. While the combination of DHEA and conjugated oral contraceptives has led to increased bone strength and decreased bone loss, the beneficial effect appears to be limited to older adolescents and adults with closed physes. Potential detrimental effects on BMD were identified in younger adolescents with open physes in one study.

DISCUSSION

Due to the lack of apparent benefit of DHEA in women with AN and its potential detrimental effect on BMD in young patients with AN, current evidence does not support the use of DHEA.

PUBLIC SIGNIFICANCE

This study demonstrates that women with anorexia nervosa have abnormal levels of dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS), which have been suggested by previous studies to play a role in the development of low bone density in this condition. However, current evidence does not support the use of DHEA as a treatment to preserve bone health in patients with anorexia nervosa given the lack of clear benefit following its use and also because of a potential detrimental effect on bone mineral density in young patients with anorexia nervosa.

Glucose Metabolism in Osteoblasts in Healthy and Pathophysiological Conditions

Bone tissue in vertebrates is essential to performing movements, to protecting internal organs and to regulating calcium homeostasis. Moreover, bone has also been suggested to contribute to whole-body physiology as an endocrine organ, affecting male fertility; brain development and cognition; and glucose metabolism. A main determinant of bone quality is the constant remodeling carried out by osteoblasts and osteoclasts, a process consuming vast amounts of energy. In turn, clinical conditions associated with impaired glucose metabolism, including type I and type II diabetes and anorexia nervosa, are associated with impaired bone turnover. As osteoblasts are required for collagen synthesis and matrix mineralization, they represent one of the most important targets for pharmacological augmentation of bone mass. To fulfill their function, osteoblasts primarily utilize glucose through aerobic glycolysis, a process which is regulated by various molecular switches and generates adenosine triphosphate rapidly. In this regard, researchers have been investigating the complex processes of energy utilization in osteoblasts in recent years, not only to improve bone turnover in metabolic disease, but also to identify novel treatment options for primary bone diseases. This review focuses on the metabolism of glucose in osteoblasts in physiological and pathophysiological conditions.

Intensive weight gain therapy in patients with anorexia nervosa results in improved serum tartrate-resistant acid phosphatase (TRAP) 5a and 5b isoform protein levels

AIM

Tartrate-resistant acid phosphatase (TRAP) exists as isoforms 5a and 5b. TRAP 5a is a biomarker of chronic inflammation and influences adipose tissue and 5b associates with bone metabolism/pathologies. The aim was to investigate the association of serum TRAP 5a/5b isoforms with fat and bone markers and anthropometric parameters in patients with anorexia nervosa (AN) during weight gain therapy.

METHODS

Twenty-five Swedish female AN patients, age 16-24 years, were treated for 12 weeks with a high-energy diet with six meals daily. Serum TRAP 5a/5b, markers of fat/glucose metabolism, markers of bone resorption and formation were measured. Parameters of bone and body composition were assessed by dual-energy X-ray absorptiometry and peripheral quantitative computed tomography.

RESULTS

BMI increased from median 15.4 kg/m² to 19.0 kg/m², p < 0.0001. TRAP 5a and 5a/5b ratio increased but TRAP 5b decreased during the study. TRAP Δ5a and Δ5b correlated with Δinsulin and Δadiponectin, respectively. TRAP 5b correlated with trabecular density at start but not at week 12. At 12 weeks, TRAP 5b correlated with CTX, and Δ decrease in TRAP 5b correlated to Δ increase in bone-specific alkaline phosphatase.

CONCLUSIONS

This clinical interventional study resulted in increased BMI in patients with AN. The decreased TRAP 5b protein levels confirm a role for TRAP 5b as a marker of bone resorption, whereas increased TRAP 5a seemed to derive from systemic changes in bone as well as metabolic changes. The combined detection of TRAP 5a and TRAP 5b in serum could be an indicator of improved bone metabolism.

LEVEL OF EVIDENCE

Level III, prospective interventional cohort study.

Bone mineral density comparison of adolescents with constitutional thinness and anorexia nervosa

BACKGROUND

The negative impact of anorexia nervosa (AN) on bone health is well defined. However, there are very few studies evaluating the effect of constitutional thinness on bone health, especially in the adolescent period and in the male gender. The aim of this study is to compare the bone mineral density (BMD) measurements of adolescents with AN and with constitutional thinness.

METHODS

Between April 2013 and March 2014, 40 adolescents with AN and 36 adolescents with constitutional thinness participated in the study. The femoral neck and lumbar spine BMD were measured by dual energy X-ray absorptiometry (DXA).

RESULTS

Mean lumbar z and BMD scores of adolescents with constitutional thinness were significantly lower than in adolescents with AN, whereas the mean femoral z and BMD scores were not significantly different. When males were compared separately, lumbar z and BMD values of the constitutionally thin group were found to be significantly lower than in the AN group. This difference was not significant for females.

CONCLUSIONS

The difference between the male and female results of our study suggested two hypotheses. The significantly lower BMD values in constitutionally thin boys are attributed to their longer duration of low body mass index (BMI). Although the duration of low BMI is also longer for constitutionally thin girls, similar BMD values of AN and constitutionally thin female groups are attributed to the additional negative impact of estrogen deficiency on the bone health of girls with AN.

Bone metabolism in anorexia nervosa and hypothalamic amenorrhea

Anorexia nervosa (AN) and hypothalamic amenorrhea (HA) are states of chronic energy deprivation associated with severely compromised bone health. Poor bone accrual during adolescence followed by increased bone loss results in lifelong low bone density, degraded bone architecture, and higher risk of fractures, despite recovery from AN/HA. Amenorrhea is only one of several compensatory responses to the negative energy balance. Other hypothalamic-pituitary hormones are affected and contribute to bone deficits, including activation of hypothalamic-pituitary-adrenal axis and growth hormone resistance. Adipokines, particularly leptin, provide information on fat/energy stores, and gut hormones play a role in the regulation of appetite and food intake. Alterations in all these hormones influence bone metabolism. Restricted in scope, current pharmacologic approaches to improve bone health have had overall limited success.

Differentiating constitutional thinness from anorexia nervosa in DSM 5 era

INTRODUCTION

Constitutional thinness (CT) is an underweight state characterized by normal menstruations and no change in feeding behaviour. Thinness is the only resemblance between Anorexia Nervosa (AN) and CT. Removal of amenorrhea from the new DSM 5 definition of AN might result in misdiagnosis between these two populations. The objective of this study was to compare CT, AN and Control subjects in terms of biological, anthropometric, and psychological markers in order to better distinguish AN from CT subjects.

MATERIALS AND METHODS

Body composition, nutritional markers, pituitary hormones, bone markers and psychological scores were evaluated in three groups of young women: fifty-six CT, forty restrictive-type AN and fifty-four Control subjects. For every marker, a receiver Operator Characteristics (ROC) curve was calculated to evaluate the accuracy of differentiation between AN and CT groups.

RESULTS

For most studied parameters, CT subjects were similar to Controls but dramatically different from AN subjects. DEBQ Restrained Eating subscale score was identified by ROC data analysis as the only psychological parameter tested to successfully differentiate AN from CT. Free-T3 and Leptin were shown to be powerful markers to differentiate AN and CT populations as they were highly specific and sensitive ones.

CONCLUSION

The exclusive use of psychological testing criteria is not always sufficient to differentiate AN and CT patients. Minimally, additional testing of Free T3 levels, which is cheap and widely accessible for general practitioners, should be completed to avoid misdiagnosis which could result in the implementation of ineffective treatment plans and social stigmatization for CT women.

Bone metabolism in adolescent girls with eating disorders and weight loss: independent effects of weight change, insulin-like growth factor-1 and oestradiol

Adolescents with eating disorders (ED) are at risk of developing osteoporosis if weight is not recovered. Previous investigations do not separate the effects of weight change per se from those of concomitant hormonal changes. In this investigation serum osteocalcin (OC), C-terminal telopeptide of collagen (CTX), insulin-like growth factor-1 (IGF-1) and oestradiol were measured at assessment of 498 girls with ED and during weight gain of 59 girls. At assessment, OC concentrations were associated independently with weight (change), IGF-1 and oestradiol. Low weight, a high rate of weight loss and the hormone concentrations were associated with low OC. Low weight and high rate of weight loss were associated with high CTX concentrations but there were no associations independent of weight (change) with the hormones. During weight recovery, OC and CTX were independently and positively associated with weight, weight gain, IGF-1 and oestradiol. Bone metabolism markers are related to weight change independently of IGF-1 and oestradiol during both weight loss and weight gain. During weight gain, when pubertal development and growth are resumed there is an additional independent positive association between the markers and IGF-1 and oestradiol. These relationships are strongest in premenarcheal girls.

Bone health in eating disorders

Eating disorders (EDs) put adolescents and young adults at risk for impaired bone health. Low bone mineral density (BMD) with ED is caused by failure to accrue peak bone mass in adolescence and bone loss in young adulthood. Although ED patients diagnosed with bone loss may be asymptomatic, some suffer bone pains and have increased incidence of fractures. Adolescents with ED are prone to increased prevalence of stress fractures, kyphoscoliosis and height loss. The clinical picture of the various EDs involves endocrinopathies that contribute to impaired bone health. Anorexia nervosa (AN) is characterized by low bone turnover, with relatively higher osteoclastic (bone resorptive) than osteoblastic (bone formation) activity. Bone loss in AN occurs in both the trabecular and cortical bones, although the former is more vulnerable. Bone loss in AN has been shown to be influenced by malnutrition and low weight, reduced fat mass, oestrogen and androgen deficiency, glucocorticoid excess, impaired growth hormone-insulin-like growth factor 1 axis, and more. Bone loss in AN may not be completely reversible despite recovery from the illness. Treatment modalities involving hormonal therapies have limited effectiveness, whereas increased caloric intake, weight gain and resumption of menses are essential to improved BMD.

Constitutional thinness and anorexia nervosa: a possible misdiagnosis?

Clinical and biological aspects of restrictive anorexia nervosa (R-AN) are well documented. More than 10,000 articles since 1911 and more than 600 in 2013 have addressed R-AN psychiatric, somatic, and biological aspects. Genetic background, ineffectiveness of appetite regulating hormones on refeeding process, bone loss, and place of amenorrhea in the definition are widely discussed and reviewed. Oppositely, constitutional thinness (CT) is an almost unknown entity. Only 32 articles have been published on this topic since 1953. Similar symptoms associating low body mass index, low fat, and bone mass are reported in both CT and R-AN subjects. Conversely, menses are preserved in CT women and almost the entire hormonal profile is normal, except for leptin and PYY. The aim of the present review is to alert the clinician on the confusing clinical presentation of these two situations, a potential source of misdiagnosis, especially since R-AN definition has changed in DSM5.

Ghrelin: central and peripheral implications in anorexia nervosa

Increasing clinical and therapeutic interest in the neurobiology of eating disorders reflects their dramatic impact on health. Chronic food restriction resulting in severe weight loss is a major symptom described in restrictive anorexia nervosa (AN) patients, and they also suffer from metabolic disturbances, infertility, osteopenia, and osteoporosis. Restrictive AN, mostly observed in young women, is the third largest cause of chronic illness in teenagers of industrialized countries. From a neurobiological perspective, AN-linked behaviors can be considered an adaptation that permits the endurance of reduced energy supply, involving central and/or peripheral reprograming. The severe weight loss observed in AN patients is accompanied by significant changes in hormones involved in energy balance, feeding behavior, and bone formation, all of which can be replicated in animals models. Increasing evidence suggests that AN could be an addictive behavior disorder, potentially linking defects in the reward mechanism with suppressed food intake, heightened physical activity, and mood disorder. Surprisingly, the plasma levels of ghrelin, an orexigenic hormone that drives food-motivated behavior, are increased. This increase in plasma ghrelin levels seems paradoxical in light of the restrained eating adopted by AN patients, and may rather result from an adaptation to the disease. The aim of this review is to describe the role played by ghrelin in AN focusing on its central vs. peripheral actions. In AN patients and in rodent AN models, chronic food restriction induces profound alterations in the « ghrelin » signaling that leads to the development of inappropriate behaviors like hyperactivity or addiction to food starvation and therefore a greater depletion in energy reserves. The question of a transient insensitivity to ghrelin and/or a potential metabolic reprograming is discussed in regard of new clinical treatments currently investigated.

Bone metabolism markers in adolescent girls with eating disorders and weight loss: effects of growth, weight trend, developmental and menstrual status

Serum concentrations of osteocalcin (OC) decrease and those of C-terminal telopeptide of type 1 collagen (CTX) increase during weight loss in adolescent girls with eating disorders (ED). The impact of weight loss on bone metabolism markers is greatest in premenarcheal girls.

INTRODUCTION

Adolescents with ED stand a risk of not reaching optimal peak bone mass and develop osteoporosis. Previous investigations are contradictory as to how markers of bone formation and resorption change during weight loss and nutritional rehabilitation.

METHODS

Serum OC and CTX were measured at assessment of 461 adolescent girls with ED and during treatment of 55 girls with anorexia nervosa. Bone metabolism was related to weight, weight change and growth rate.

RESULTS

At assessment, OC concentrations were positively correlated with growth rate and inversely with age and (rate of) weight loss. Growth rate was the only predictor of CTX concentrations in premenarcheal girls. In postmenarcheal girls, CTX concentrations were inversely correlated with age and rate of weight loss. During weight gain, there was an increase of OC concentrations. CTX concentrations decreased at the onset of weight gain and increased when near normal weight was reached.

CONCLUSIONS

Bone formation markers decrease and resorption markers increase during weight loss. The effects are independent of menstrual status but the impact on bone formation markers is greater in young, premenarcheal girls. Markers are normalised during weight gain but it is conceivable that repeated and/or prolonged weight loss in adolescents reduces peak bone mass.

Normal inhibin B levels suggest partial preservation of gonadal function in adult male patients with anorexia nervosa

INTRODUCTION

The impact of undernutrition on endocrine and exocrine gonadatrope function is poorly known in male anorexia nervosa (AN) patients.

AIM

The aim of this study was to compare the pituitary-gonadal function of male AN subjects with that of healthy controls, Kallmann syndrome (KS) patients, and female AN subjects.

METHODS

Observational monocentric cross-sectional study performed in 31 male and 25 female subjects with restrictive-type AN, 22 male and 20 female controls, and nine male KS patients.

MAIN OUTCOME MEASURES

Hormonal parameters are as follows: follicule stimulating hormone (FSH), luteinizing hormone (LH), sex hormone binding globulin, estradiol, testosterone, inhibin B, thyroid hormones, growth hormone (GH), insulin-like growth factor 1 (IGF-1), cortisol, adrenocorticotropic hormone (ACTH), dehydroepiandrosterone sulfate, and leptin.

RESULTS

Similar abnormalities of free T3, GH, IGF-I, cortisol, and leptin were found in men as in AN women with equivalent undernutrition status when compared with corresponding controls. Low levels of LH, FSH were found in both male and female AN patients. In male AN, total testosterone was found lower than in controls but higher than in KS, while a lack of estradiol was noticed in AN women. Sex hormones variations were directly related to weight gain only in AN men. No relationship was found between sex hormones and leptin variation for both sexes. In AN men, inhibin B levels were similar to that of controls and did not correlate with testosterone levels.

CONCLUSIONS

Significant differences of undernutrition impact on gonadal status were noticed between male and female AN subjects, including partial preservation of testosterone release and probable preservation of exocrine function, according to the normal inhibin B levels.

Ghrelin and obestatin circadian levels differentiate bingeing-purging from restrictive anorexia nervosa

CONTEXT

Anorexia nervosa (AN) patients present with restrictive food behavior (AN-R). Some of them develop episodes of bulimia (AN-BP) without any clear pathophysiological explanation to date. Their clinical differentiation is important but not easily performed. Orexigenic/anorexigenic peptides measurements could provide some clues for that matter.

OBJECTIVE

The objective of the study was to determine whether the circadian profile of total and acylated ghrelin, obestatin, and peptide YY (PYY) levels is different in AN-R subjects when compared with AN-BP patients.

DESIGN AND SETTINGS

This was a cross-sectional study in an endocrinological unit.

PATIENTS AND CONTROL SUBJECTS

Four groups of age-matched young women: 22 AN-R, 10 AN-BP, 16 normal-weight bulimia nervosa (BN), and nine controls.

MAIN OUTCOME MEASURES

Twelve-point circadian profiles of plasma total and acylated ghrelin, obestatin, and PYY were measured.

RESULTS

Total and acylated ghrelin and obestatin circadian levels were increased in AN-R when compared with controls but decreased in both AN-BP and BN groups (P < 0.001). PYY was decreased in all groups with eating disorders. Acylated to total ghrelin ratio was decreased in AN-BP and BN (P < 0.001), whereas obestatin to acylated ghrelin and PYY to acylated ghrelin ratios were increased in both groups with bingeing-purging behavior (P < 0.0001).

CONCLUSIONS

Patients with AN-associated bingeing-purging behavior present a very different profile of appetite regulatory peptides when compared with the pure restrictive type. The assessment of ghrelin (and eventually obestatin) could be of particular interest for differential diagnosis. Very low ghrelin levels and increased anorexigenic to orexigenic peptide ratios suggest either a lack of adaptation to a starvation state or a higher facility to cope with undernutrition.

Hormonal profile heterogeneity and short-term physical risk in restrictive anorexia nervosa

CONTEXT

The relevance of hormonal assessment in anorexia nervosa (AN) management is still unclear. The short-term physical risk during undernutrition period of the disease is partially predicted by anthropometric and electrolytic parameters.

OBJECTIVE

The objective of the study was to evaluate hormonal profiles in a large cohort of AN and their relationship with critical states.

DESIGN AND SETTING

This was an observational monocentric cross-sectional study performed in the endocrinological unit.

PATIENTS AND OTHER PARTICIPANTS

Participants included 210 young female subjects with restrictive-type AN and 42 female controls of comparable age.

MAIN OUTCOME MEASURES

The following hormonal parameters were measured: thyroid hormones, GH, IGF-I, cortisol, oestradiol, FSH, LH, SHBG, dehydroepiandrosterone sulfate, plasma metanephrines, and bone markers. Their relation with registered short-term evolution of AN subjects after hormonal assessment was evaluated.

RESULTS

Except for metanephrines and dehydroepiandrosterone sulfate, most of the hormonal abnormalities previously reported in AN were confirmed. The manifestation of these hormonal abnormalities started below different body mass index (BMI) levels, ranging between 17 and 15 kg/m(2), even though an important percentage of normal values for every parameter was still noticed for very low BMIs. All patients who developed critical states during the 3 months after the hormonal assessment presented with BMI less than 15 kg/m(2) and a very increased level of cortisol, GH, and increased values of metanephrines.

CONCLUSIONS

The hormonal response to undernutrition is heterogeneous in a large population with restrictive AN. In clinical practice, metanephrines, GH, and/or cortisol data could be used as important predictors for severe short-term outcome.

Prevalence and clinical determinants of low bone mineral density in anorexia nervosa

OBJECTIVE

To determine the prevalence of low bone mass in anorexia nervosa (AN) and the association with clinical parameters.

METHODS

A cross-sectional study on 286 Caucasian women with AN. Bone mineral density (BMD) was measured with DXA. Low BMD was defined as a Z-score <or= -1.0 in at least one site (lumbar spine or femoral neck).

RESULTS

A Z-score of <or= -1.0 in at least one of these sites was found in 46.9%. In comparison with the patients with normal BMD, in patients with a low BMD both the BMI at the time of DXA (p=0.005) and the lowest BMI ever (p<0.001) was lower. These patients also had a longer duration of AN (p=0.047). The decline of BMI per year between highest BMI ever and BMI at time of DXA was more rapid in subjects with a normal BMD (p=0.016) as compared to patients with low BMD. Low BMD was found to be independently associated with 'lowest BMI ever' (OR: 0.78; 95%CI=0.66-0.93), and with 'BMI decline per year' (OR: 0.83; 95%CI=0.71-0.97).

CONCLUSION

We conclude that low BMD is frequent in AN. The best indicator of low BMD appeared to be the lowest reported BMI ever.

Organic background of restrictive-type anorexia nervosa suggested by increased serotonin 1A receptor binding in right frontotemporal cortex of both lean and recovered patients: [18F]MPPF PET scan study

BACKGROUND

Serotonin (5-HT) pathway abnormalities were demonstrated in anorexia nervosa (AN). Brain imaging studies on 5-HT receptors support this evidence. 4-(2-methoxyphenyl)-1-[2-(N-2-pyridinyl)-p-fluorobenzamido]-ethylpiperazine ([(18)F]MPPF) is a selective 5-HT(1A) receptor antagonist with an affinity close to that of endogenous 5-HT.

METHODS

In 24 subjects including 8 lean restrictive-type AN patients, 9 recovered from restrictive-type AN subjects and 7 age-matched control subjects, we assessed in vivo brain [(18)F]MPPF binding by positron emission tomography and eating-related psychopathological traits. Inter-groups differences in [(18)F]MPPF binding were evaluated by voxel-based analyses.

RESULTS

Restrictive AN patients presented increased [(18)F]MPPF binding in a selective area of the right cortex including part of the superior temporal gyrus, inferior frontal gyrus, parietal operculum, and temporoparietal junction. Striking regional similarities of increased [(18)F]MPPF binding were found in recovered from AN subjects. Most of the psychiatric scores were increased in restrictive AN patients, and elevated perfectionism and interpersonal distrust scores were noticed in subjects recovered from AN.

CONCLUSIONS

The persistent increased 5-HT(1A) receptor binding in frontotemporal region of recovered AN concomitantly with specific psychopathological traits support the hypothesis of an organic dysfunction of this area and corroborates with previous literature reports of AN cases induced by temporal lesions.

Growth hormone, insulin-like growth factors, and the skeleton

GH and IGF-I are important regulators of bone homeostasis and are central to the achievement of normal longitudinal bone growth and bone mass. Although GH may act directly on skeletal cells, most of its effects are mediated by IGF-I, which is present in the systemic circulation and is synthesized by peripheral tissues. The availability of IGF-I is regulated by IGF binding proteins. IGF-I enhances the differentiated function of the osteoblast and bone formation. Adult GH deficiency causes low bone turnover osteoporosis with high risk of vertebral and nonvertebral fractures, and the low bone mass can be partially reversed by GH replacement. Acromegaly is characterized by high bone turnover, which can lead to bone loss and vertebral fractures, particularly in patients with coexistent hypogonadism. GH and IGF-I secretion are decreased in aging individuals, and abnormalities in the GH/IGF-I axis play a role in the pathogenesis of the osteoporosis of anorexia nervosa and after glucocorticoid exposure.

Current concepts in bone and reproductive health in adolescents with anorexia nervosa

Anorexia nervosa (AN) initiates an adaptive response at the level of the hypothalamus, which results in a complex interplay involving most elements of the neuroendocrine axis. Consequences of onset of disease in adolescence include amenorrhoea, pubertal arrest with potential loss of target height, and osteoporosis with reduced capacity for future attainment of peak bone mass. With recovery, delay in restoration of menses is common. Hormonal therapies for restoration of bone mineral density (BMD) in adolescents have shown limited efficacy. This review will discuss the reproductive endocrine effects of AN in adolescence, and discuss new investigative tools for monitoring restoration of reproductive function and BMD in this population.

Follicle-stimulating hormone does not directly regulate bone mass in human beings: evidence from nature

OBJECTIVE

To evaluate the effect of FSH levels in the development of human osteoporosis.

DESIGN

Case-series study.

SETTING

Gynecology department in a teaching hospital.

PATIENT(S)

A total of 8 women diagnosed with Kallman syndrome (KS) were compared with 11 with Turner syndrome and 11 with pure gonadal dysgenesia (GD, karyotype 46,XX).

INTERVENTION(S)

We assessed the pituitary-gonadal axis, bone turnover markers, bone mass, and patient characteristics.

MAIN OUTCOME MEASURE(S)

Bone mineral density as assessed by dual-energy X-ray absorptiometry, plasma FSH, LH, E(2), osteocalcin (BGP), and urinary type I collagen cross-linked N-telopeptide. Other biochemical markers included 25-hydroxyvitamin D, as well as parathyroid hormone and urine concentration of calcium and creatinine.

RESULT(S)

In girls with Turner syndrome and GD, FSH (64.03 +/- 29.2 and 90.08 +/- 22.41 mIU/mL, respectively) and LH (45.29 +/- 11.90 and 48.83 +/- 12.44 mIU/mL, respectively) levels were significantly higher compared with those observed in girls with KS (FSH: 1.87 +/- 0.64 and LH: 1.02 +/- 0.57), whereas no differences were detected in E(2) or bone marker levels. Bone mineral density correlated positively with FSH levels but not with E(2); however, after adjusting for previous growth-hormone therapy, these differences were not found. In addition, bone mineral density in spine and total hip was significantly lower in patients with KS.

CONCLUSION(S)

Follicle-stimulating hormone does not appear to have a major role in the development of bone loss in young women with primary amenorrhea.

A 2-year prospective study of bone metabolism and bone mineral density in adolescents with anorexia nervosa

Osteopenia and osteoporosis are complications of adolescent anorexia nervosa (AN) and may result in a permanent deficit of bone mass in adulthood. It is still unclear if a complete catch-up in bone mineral density (BMD) is possible after weight rehabilitation in AN. METHODS. We investigated bone formation (bAP, PICP), bone resorption (CTX) and BMD (lumbar spine, femoral neck) along with endocrinological parameters in 19 girls with AN (14.4 +/- 1.6 years) and in 19 healthy controls for 2 years after inpatient re-feeding. RESULTS. Re-feeding normalised bone formation activity in patients. The pattern of bone turnover in patients after 2 years was similar to the pattern healthy controls had shown 2 years before. BMD of patients was significantly lower than in controls and did not change throughout the entire study. CONCLUSIONS. Weight rehabilitation leads to prolonged normalization of bone turnover in adolescent AN. Since we could not observe a "catch up" effect in BMD of girls with AN in a 2-year follow-up, BMD of these patients needs to be carefully monitored until adulthood to detect early osteoporosis.

Marked increases in bone mineral density and biochemical markers of bone turnover in patients with anorexia nervosa gaining weight

Anorexia nervosa (AN) is a life-threatening eating disorder characterized by an inability to maintain a normal body weight and amenorrhoea, often associated with osteoporosis and increased risk of fragility fractures. Bone metabolism, including markers of bone turnover (serum total alkaline phosphatase, bone alkaline phosphatase [bone AP], osteocalcin [OC] and type I collagen C-telopeptide breakdown products [sCTX]) and bone mineral density (BMD) by dual energy X-ray absorptiometry (DXA) at the spine and at the hip, were evaluated in 55 consecutive women with AN undergoing a 3-month intensive nutritional rehabilitation program. The control group was constituted of 25 healthy young medical students. In AN patients body weight increased during the 3-month nutritional program from 37.8+/-5.1 (mean+/-SD) to 51.5+/-4.5 kg. The corresponding BMI rose to values >17.5 kg/m(2) in all patients. Mean BMD significantly rose by 2.6+/-3.5% and 1.1+/-3.6% at the hip and at the spine, respectively. The markers of bone formation, serum bone AP and osteocalcin, significantly rose by two-folds, while sCTX decreased by 16%. The changes in hip BMD were positively related (p<0.005) to changes in body weight and in bone AP (p<0.02) while the changes in spine BMD were positively related to changes in serum osteocalcin (p<0.05). In the 25 patients who attended the 12-month posttreatment control, mean body weight significantly decreased by 3.6+/-6.0 kg and this was not associated with any significant change in BMD values. In the patients in whom BMI fell again below 17.5 kg/m(2) hip BMD values decreased significantly. On the contrary, in the patients who maintained BMI >17.5 kg/m(2), BMD values continued to rise up to values over the 15-month observation of 4.8+/-6.2 and 7.1+/-12.1 at the spine and hip, respectively. In conclusion, we have demonstrated that substantial gains in weight in women with chronic AN are associated with remarkable increases in BMD at both the hip and the spine. If weight is maintained, the overall improvement approach 1 SD within 1 year. The changes in both weight and BMD are correlated with improvements in bone formation markers and diminutions in a marker of bone resorption.

Open Issues in Anorexia Nervosa: Prevention and Therapy of Bone Loss

Anorexia nervosa and diet-induced amenorrhea have an important impact not only on gynecological health but also on bone mass, especially if the disease is not promptly recognized and treated. This is particularly important because these conditions usually arise in adolescence, when peak bone mass is normally achieved. In this article we discuss the therapeutic issues related to bone loss associated with eating disorders.