Changes in bone mineral density, body composition and biochemical markers of bone turnover during weight gain in adolescents with severe anorexia nervosa: a 1-year prospective study

Transition of young adults with metabolic bone diseases to adult care

As more accurate diagnostic tools and targeted therapies become increasingly available for pediatric metabolic bone diseases, affected children have a better prognosis and significantly longer lifespan. With this potential for fulfilling lives as adults comes the need for dedicated transition and intentional care of these patients as adults. Much work has gone into improving the transitions of medically fragile children into adulthood, encompassing endocrinologic conditions like type 1 diabetes mellitus and congenital adrenal hyperplasia. However, there are gaps in the literature regarding similar guidance concerning metabolic bone conditions. This article intends to provide a brief review of research and guidelines for transitions of care more generally, followed by a more detailed treatment of bone disorders specifically. Considerations for such transitions include final adult height, fertility, fetal risk, heritability, and access to appropriately identified specialists. A nutrient-dense diet, optimal mobility, and adequate vitamin D stores are protective factors for these conditions. Primary bone disorders include hypophosphatasia, X-linked hypophosphatemic rickets, and osteogenesis imperfecta. Metabolic bone disease can also develop secondarily as a sequela of such diverse exposures as hypogonadism, a history of eating disorder, and cancer treatment. This article synthesizes research by experts of these specific disorders to describe what is known in this field of transition medicine for metabolic bone diseases as well as unanswered questions. The long-term objective is to develop and implement strategies for successful transitions for all patients affected by these various conditions.

Changes in trabecular bone score and bone density in female adolescents with anorexia nervosa: a longitudinal study

Impaired bone health is a common complication of anorexia nervosa (AN). We aimed to assess longitudinal changes in bone mineral density (BMD) and trabecular bone score (TBS), a measure of bone quality, in female adolescents with anorexia nervosa (AN). We conducted a retrospective longitudinal study of 41 female adolescents with AN who underwent two dual-energy X-ray absorptiometry (DXA) scans. Clinical data, including age, weight, height, body mass index (BMI), and DXA measurements were retrieved from the medical charts. Lumbar bone mineral apparent density (BMAD) was calculated to correct for size. Changes (Δ) in BMD, BMAD, and TBS were examined for correlations with clinical characteristics. Mean ages at the time of DXA scans were 14.8±1.9 and 16.8±2.0 years. There was a significant improvement in anthropometric parameters and DXA measurements at the second DXA scan. However, these values were still significantly lower than expected in the general population. The Δlumbar BMD Z-score was 0.3±0.7, the Δlumbar BMAD Z-score was 0.2±0.7 and the ΔTBS Z-score was 0.5±0.7. ΔTBS Z-score was positively correlated with Δheight Z-score, Δweight Z-score and ΔBMI Z-scores, and negatively correlated height Z-score, weight Z-score and TBS Z-scores at the first DXA scan (p<0.05). Δheight Z-score, ΔBMI Z-score and the progression from early to late puberty were identified as significant independent predictors of Δlumbar BMAD Z-score (p<0.05). During two years of treatment, both BMD and TBS increased significantly. Improvement in height and in weight status, and progression in puberty are predictors of improvement in BMD and TBS.

Bone Perspectives in Functional Hypothalamic Amenorrhoea: An Update and Future Avenues

One of the most important and potentially long-lasting detrimental consequences of Functional Hypothalamic Amenorrhoea (FHA) is on skeletal homeostasis. Beyond oestrogen deficiency, FHA is associated with a cascade of additional neuro-endocrine and metabolic alterations, some adaptive, but which combine to disrupt skeletal homeostasis. Ultimately, this leads to a two-fold increased risk of fractures in women with FHA compared to healthy eumenorrhoeic women. Although the cornerstone of management of FHA-related bone loss remains recovery of menses via restoration of metabolic/psychological balance, there is rapidly developing evidence for hormonal manipulations (with a particular emphasis on route of administration) and other pharmacological treatments that can protect or improve skeletal homeostasis in FHA. In this mini-review, we provide an update on the pathophysiology, clinical management and future avenues in the field from a bone perspective.

Anorexia Nervosa and Osteoporosis

Patients with anorexia nervosa (AN) often experience low bone mineral density (BMD) and increased fracture risk, with low body weight and decreased gonadal function being the strongest predictors of the observed bone mineral deficit and fractures. Other metabolic disturbances have also been linked to bone loss in this group of patients, including growth hormone resistance, low insulin-like growth factor-1 (IGF-1) concentrations, low leptin concentrations, and hypercortisolemia. However, these correlations lack definitive evidence of causality. Weight restoration and resumption of menstrual function have the strongest impact on increasing BMD. Other potential treatment options include bisphosphonates and teriparatide, supported by data from small clinical trials, but these agents are not approved for the treatment of low BMD in adolescents or premenopausal women with AN.

Bone health in functional hypothalamic amenorrhea: What the endocrinologist needs to know

In the original definition by Klinefelter, Albright and Griswold, the expression "hypothalamic hypoestrogenism" was used to describe functional hypothalamic amenorrhoea (FHA). Given the well-known effects of estrogens on bone, the physiopathology of skeletal fragility in this condition may appear self-explanatory. Actually, a growing body of evidence has clarified that estrogens are only part of the story. FHA occurs in eating disorders, overtraining, and during psychological or physical stress. Despite some specific characteristics which differentiate these conditions, relative energy deficiency is a common trigger that initiates the metabolic and endocrine derangements contributing to bone loss. Conversely, data on the impact of amenorrhoea on bone density or microarchitecture are controversial, and reduced bone mass is observed even in patients with preserved menstrual cycle. Consistently, oral estrogen-progestin combinations have not proven beneficial on bone density of amenorrheic women. Low bone density is a highly prevalent finding in these patients and entails an increased risk of stress or fragility fractures, and failure to achieve peak bone mass and target height in young girls. Pharmacological treatments have been studied, including androgens, insulin-like growth factor-1, bisphosphonates, denosumab, teriparatide, leptin, but none of them is currently approved for use in FHA. A timely screening for bone complications and a multidisciplinary, customized approach aiming to restore energy balance, ensure adequate protein, calcium and vitamin D intake, and reverse the detrimental metabolic-endocrine changes typical of this condition, should be the preferred approach until further studies are available.

Prebiotic Food Intake May Improve Bone Resorption in Japanese Female Athletes: A Pilot Study

The aim of the present study was to clarify the influence of inulin and lactulose-fortified prebiotic food intakes on bone metabolism turnover among Japanese female athletes. The participants included 29 female athletes aged 18–25 years. They were requested to consume their habitual foods or drinks with one pack of prebiotic food every day for 12 weeks. Dietary intake, training time, body composition, blood sample, and fecal microbiota were assessed during this intervention period. Body composition, total energy intake, and training time of the participants revealed no significant changes during the intervention period. The occupation ratio of Bifidobacterium spp. was significantly increased at 3 and 4 weeks (18.0 ± 8.3% and 17.6 ± 8.5%, respectively) compared to that of pre-intervention (11.7 ± 7.3%) (p = 0.019 and p = 0.035, respectively). The serum TRACP-5b level was significantly decreased at 12 weeks (363 ± 112 mU/dL) compared to that at baseline (430 ± 154 mU/dL) (p = 0.018). These results suggest that the prebiotic food used in this study might have beneficial effects on bone health and gut microbial environment among female athletes. Further studies are warranted to identify the mechanism of the prebiotics–gut–bone axis.

Body Composition in Adolescents and Young Adults with Anorexia Nervosa: A Clinical Review

BACKGROUND

Anorexia nervosa is a serious health condition characterized by a significant low body weight and alteration in body composition components.

AIM

In the current paper, we aim to summarize the available literature concerning changes in body fat, lean, and bone masses, during anorexia nervosa and after complete weight restoration.

METHODS

Data were summarized using a narrative approach based on clinical expertise in the interpretation of the available evidence base in the literature.

RESULTS

The available data revealed three main findings. Firstly, anorexia nervosa causes a significant reduction in body fat mass, however it is completely restored after short-term weight normalization but with a central adiposity phenotype that does not seem to negatively influence treatment outcomes and appears to normalize after 1 year of normal weight maintenance. Secondly, anorexia nervosa causes a significant reduction in bone mineral density, but weight restoration is associated first (≈12 months) with stabilization of bone mineral density, followed by improvements (after ≈16 months); and finally, with complete normalization (after ≈30 months) after normal-weight maintenance. Thirdly, during anorexia nervosa loss of lean and skeletal body mass occurring in particular from the extremities rather than the central regions has been consistently reported, especially in patients with a Body Mass Index (BMI) ≤ 16.5 Kg/m2 however short-term weight restoration is associated with complete normalization.

CONCLUSION

Anorexia nervosa adversely affects body composition, however this medical complication seems to be reversible through the main treatment strategy of body weight restoration followed by normal weight maintenance, and this should be openly discussed with patients.

Association between non-Caucasian-specific ASCC1 gene polymorphism and osteoporosis and obesity in Korean postmenopausal women

INTRODUCTION

Osteoporosis is a common disorder characterized by decreased bone mineral density (BMD). Interestingly, osteoporosis and obesity have several similar features, including a genetic predisposition and a common bone marrow stem cell. With aging, the composition of bone marrow shifts to adipocytes, osteoclast activity increases, and osteoblast function declines, resulting in osteoporosis.

MATERIALS AND METHODS

We performed a genome-wide association study (GWAS) analysis with osteoporosis and body mass index (BMI) and did identify an association in 349 and 384 SNPs by filtering with the significant p values (p < 0.001) of BMI and osteoporosis, respectively.

RESULTS

Only three of those SNPs were common (rs2326365, rs7097028, and rs11000205) between the SNPs significantly associated with BMI and/or osteoporosis in Korean Association REsource (KARE) females. Two of the three SNPs belonged to the ASCC1 gene and one to the FAM50B gene. We carried out a minor allele frequency (MAF) analysis of the rs7097028 and rs11000205 SNPs in the ASCC1 gene with a geographic genome variant browser. Both rs7097028 and rs11000205 in the ASCC1 gene were seen mostly in African and Southeast Asian populations.

CONCLUSIONS

Our results suggest that the ASCC1 gene is a significant genetic factor for determining the risk for both osteoporosis and obesity in KARE postmenopausal females.

Anorexia Nervosa and Osteoporosis: Pathophysiology and Treatment

Anorexia nervosa (AN) affects 2.9 million people, many of whom experience bone loss and increased fracture risk. In this article, we review data on the underlying pathophysiology of AN-related osteoporosis and possible approaches to disease management. Available research suggests that low body weight and decreased gonadal function are the strongest predictors of bone loss and fractures in patients with AN. Additionally, other metabolic disturbances have been linked to bone loss, including growth hormone resistance, low leptin concentrations, and hypercortisolemia, but those correlations are less consistent and lack evidence of causality. In terms of treatment of AN-related bone disease, weight gain has the most robust impact on bone mineral density (BMD). Restoration of gonadal function seems to augment this effect and may independently improve BMD. Bisphosphonates, insulin-like growth factor 1 supplementation, and teriparatide may also be reasonable considerations, however need long-term efficacy and safety data.

Longitudinal changes in bone parameters in young girls with anorexia nervosa

BACKGROUND

Anorexia nervosa (AN) during childhood and adolescence has been reported to adversely affect bone health, but few studies have investigated longitudinal changes.

METHOD

DXA-derived bone parameters and body composition were retrospectively assessed in 111 young girls with AN with a median age of 15.4 years (10.9, 19.8). In 68 (61%) vertebral fracture assessment (VFA) was performed and in 31 (28%), a follow-up DXA was performed. Correlations with growth, changes in body composition and effects of illness duration and menstruation were examined. Size adjusted DXA standard deviation scores were calculated for total body (TB) less head bone mineral content (TBLH-BMC) and lumbar spine bone mineral apparent density (LS-BMAD).

RESULTS

Mean (range) bone area (BA) for height centile was 27.1 (0-97), and mean lean mass for height centile was 28.8 (0-95) at baseline. Mean (range) LS BMAD was -1.0 (-2.6, 0.8) SDS at first and - 1.2 (-3.0, -0.2) at second DXA (p = 0.023). On follow up, lean mass for height increased from 27th centile (0, 75) to 40th centile (0, 70) (p = 0.006), and fat mass for height increased from 55 g/cm to 67 g/cm (11.3, 124.2) (p < 0.001). Duration of illness was the only negative predictor of LS BMAD (p < 0.0001). Change in height SDS was the only positive predictor of change in TBLH-BMC (r = 0.384, p = 0.037), and change in LS BMAD (r-0.934, p < 0.0001). Of 68 patients who had VFA, 4 (5.9%) had a mild vertebral fracture.

CONCLUSION

Bones are smaller and less dense in childhood/adolescent AN compared to healthy adolescents. Although there are significant gains in lean mass and fat mass, over time, BMAD SDS decreases slightly. Improvement in BMAD SDS is related to improvement in height SDS.

Bone mineral density in young adults with Prader-Willi syndrome: A randomized, placebo-controlled, crossover GH trial

CONTEXT

The prevalence of osteoporosis is increased in adults with Prader-Willi syndrome (PWS). In children with PWS, growth hormone (GH) treatment has beneficial effects on bone mineral density (BMD). BMD might deteriorate after cessation of GH at adult height (AH), while continuing GH might maintain BMD.

OBJECTIVE

To investigate the effects of GH vs placebo, and furthermore the effects of sex steroid replacement therapy (SSRT), on BMD in GH-treated young adults with PWS who had attained AH.

DESIGN

Two-year, randomized, double-blind, placebo-controlled, crossover GH study.

PATIENTS

Twenty-seven young adults with PWS were stratified for gender and BMI and then randomly and blindly assigned to receive GH (0.67 mg/m² /day) or placebo for 1 year, after which they crossed over to the alternative treatment for another year.

MEASUREMENTS

Bone mineral density of the total body (BMD_TB ) and lumbar spine (BMD_LS ) SDS were measured by dual-energy x-ray absorptiometry.

RESULTS

At AH, BMD_TB SDS was significantly lower compared to healthy peers (P < .01), while BMAD_LS SDS was similar. Both BMD_TB SDS and BMAD_LS SDS were similar during 1 year of GH vs 1 year of placebo. In hypogonadal young adults without SSRT, BMD_TB SDS and BMAD_LS SDS decreased during the 2-year study (P = .11 and P = .01), regardless of GH or placebo, while BMD_TB SDS increased in those with SSRT (P < .01).

CONCLUSIONS

Compared to GH treatment, 1 year of placebo after attainment of AH does not deteriorate BMD SDS in young adults with PWS. In addition, our data suggest that GH is not able to prevent the decline in BMD SDS in hypogonadal young adults with PWS, unless it is combined with SSRT.

Vitamin D levels strongly influence bone mineral density and bone turnover markers during weight gain in female patients with anorexia nervosa

OBJECTIVE

The aim of the study was to investigate a potential role for vitamin D status on bone mineral density (BMD) during weight gain in patients with anorexia nervosa (AN).

METHOD

Spine and hip BMD assessed by dual-energy X-ray absorptiometry (DXA), serum vitamin D (25-OH-D), N-propeptide of type I collagen (P1NP), C-terminal telopeptide of type I collagen (CTX), and intact parathyroid hormone (PTH) were measured before and after a 20-week intensive weight-restoration program in ninety-one female patients with AN and secondary amenorrhoea.

RESULTS

Ninety-one consecutive female patients (age 13-45 years; weight 39.4 ± 5.6 kg, body mass index [BMI] 15.1 ± 1.6 kg m^-2 ) were included in the study. Although weight and BMI significantly increased in all patients during treatment, mean BMD only significantly increased at the spine (1.0% ± 3.6%, p = .009). The increase in spine BMD was significantly higher only above post-treatment 25-OH-D levels of 30 ng mL^-1 (2.5% vs. 0.5%, respectively, for 25-OH-D ≥ and < 30 ng mL^-1 , p = .026). There was a significant decrease in bone resorption (CTX; p = .043) and increased bone formation (P1NP; p < .001) after weight restoration. Nevertheless, a significant increase in PTH was also found, which was inversely correlated with decreased post-treatment 25-OH-D levels (R²  = .153, p < .001).

DISCUSSION

Hypovitaminosis D may counteract the efficacy of refeeding in AN through increased bone resorption mediated by secondary hyperparathyroidism, which strongly supports the use of vitamin D supplements for bone health in AN.

Treatment strategies for the female athlete triad in the adolescent athlete: current perspectives

Since the passage of Title IX in 1972, female sports participation has dramatically increased. The benefits of physical activity, including decreased risk for heart disease and diabetes as well as improved body image and self-esteem, far outweigh the risks. However, a select population of adolescent and young adult females may experience symptoms related to the female athlete triad (Triad), which refers to the interrelatedness of energy availability, menstrual function, and bone mineral density (BMD). These conditions often manifest clinically as disordered eating behaviors, menstrual irregularity, and stress fractures; an individual may suffer from 1 or all of the Triad components simultaneously. Because of the complex nature of the Triad, treatment is challenging and requires a multidisciplinary approach. Team members often include a physician, psychologist or psychiatrist, nutritionist or dietitian, physical therapist, athletic trainer, coach, family members, and most importantly, the patient. A thorough physical examination by a primary care physician is essential to identify all organs/systems that may be impacted by Triad-related conditions. Laboratory tests, assessment of bone density, nutritional assessment, and behavior health evaluation guide the management of the female athlete with Triad-related conditions. Treatment of the Triad includes adequate caloric consumption to restore a positive energy balance; this is often the first step in successful management of the Triad. In addition, determining the cause of menstrual dysfunction (MD) and resumption of menses is very important. Nonpharmacologic interventions are the first choice; pharmacologic treatment for MD is reserved only for those patients with symptoms of estrogen deficiency or infertility. Lastly, adequate intake of calcium and vitamin D is critical for lifelong bone health. For this review, a comprehensive search of relevant databases from the earliest dates to July 2016 was performed. Keywords, including female athlete triad, adolescent female athlete, disordered eating, eating disorder, low energy availability, relative energy deficit, anorexia, bulimia, menstrual dysfunction, amenorrhea, oligoamenorrhea, bone mineral density, osteopenia, osteoporosis, stress fracture, and stress reaction, were utilized to search for relevant articles. Articles that directly addressed assessment and management of any 1 or all of the Triad components were included in this comprehensive review. The purpose of this narrative review is to provide the reader with the latest terms used to define the components of the female athlete triad, to discuss examination and diagnosis of the Triad, and lastly, to provide the reader with the latest evidence to successfully implement a multidisciplinary treatment approach when providing care for the adolescent female athlete who may be suffering from Triad-related components.

The Association between Weight Gain/Restoration and Bone Mineral Density in Adolescents with Anorexia Nervosa: A Systematic Review

Background: Reduced bone mineral density (BMD) is one of the most frequent medical complications of anorexia nervosa (AN). The purpose of this paper was to conduct a systematic review of the association between weight gain/restoration and BMD in adolescents with AN. Methods: Literature searches, study selection, method, and quality appraisal were performed independently by two authors, and data were collated using a narrative approach. Results: Of the 1156 articles retrieved, 19 studies met the inclusion criteria, and their analysis revealed four main findings. First, six studies reported that weight gain and restoration are associated with BMD stabilization after one year of follow-up from baseline. Second, seven studies with longer follow-up periods (≈16 months) reported significant improvements in BMD measures. Third, one study showed that normalization of BMD can be achieved after ≈30-month follow-up of normal-weight maintenance. Fourth, another study showed that male adolescents with AN who achieve weight gain but remain underweight may experience further BMD loss, unlike their weight-restored counterparts (BMI ≥ 19 kg/m²), who show a significant increase in BMD and bone mineral accrual rates that double those of healthy male adolescents. The first two findings can be considered robust, as they are supported by strong evidence. The third and fourth findings, however, derive from single studies and therefore require further confirmation. Conclusion: The literature supports weight gain as an effective strategy for promoting BMD increase in adolescents with AN. However, this process is slow, and improvements do not become detectable until ≈16-month follow-up.

Vitamin D status in young Swedish women with anorexia nervosa during intensive weight gain therapy

PURPOSE

Anorexia nervosa (AN) is associated with reduced bone mass and an increased fracture risk. The aim was to evaluate the vitamin D status and the association with body mass index (BMI), fat mass and bone mineral density (BMD) in patients with severe AN during a prospective intervention study of intensive nutrition therapy.

METHODS

This study comprised 25 Swedish female AN patients (20.1 ± 2.3 years), who were treated as inpatients for 12 weeks with a high-energy diet. Serum 25-hydroxyvitamin D (25(OH)D), calcium, phosphate and parathyroid hormone (PTH) were measured. BMD and body composition were assessed by dual-energy X-ray absorptiometry at study start and after 12 weeks.

RESULTS

Twenty-two patients completed the study. The mean weight gain was 9.9 kg and BMI (mean ± SD) increased from 15.5 ± 0.9 to 19.0 ± 0.9 kg/m², P < 0.0001. Fat mass increased from median 12 to 27 %. The median serum 25(OH)D level was 84 nmol/L at baseline, which decreased to 76 nmol/L, P < 0.05. PTH increased from median 21.9 to 30.0 ng/L, P < 0.0001. BMC increased during the study period, P < 0.001.

CONCLUSIONS

Serum 25(OH)D levels were adequate both at study start and completion, however, nominally decreased after the 12-week nutritional intervention. PTH increased subsequently, which coincide with the decreased 25(OH)D levels. The reduction in 25(OH)D could be due to an increased storage of vitamin D related to the increase in fat mass since vitamin D is sequestered in adipose tissue.

State of the art systematic review of bone disease in anorexia nervosa

OBJECTIVE

Low bone mineral density (BMD) is a known consequence of anorexia nervosa (AN) and is particularly concerning during adolescence, a critical time for bone accrual. A comprehensive synthesis of available data regarding impaired bone health, its determinants, and associated management strategies in AN is currently lacking. This systematic review aims to synthesize information from key physiologic and prospective studies and trials, and provide a thorough understanding of impaired bone health in AN and its management.

METHOD

Search terms included "anorexia nervosa" AND "bone density" for the period 1995-2015, limited to articles in English. Papers were screened manually based on journal impact factor, sample size, age of participants, and inclusion of a control group. When necessary, we included seminal papers published before 1995.

RESULTS

AN leads to low BMD, impaired bone quality and increased fracture risk. Important determinants are low lean mass, hypogonadism, IGF-1 deficiency, and alterations in other hormones that impact bone health. Weight gain and menses restoration are critical for improving bone outcomes in AN. Physiologic estrogen replacement as the transdermal patch was shown to increase bone accrual in one study in adolescent females with AN; however, residual deficits persist. Bisphosphonates are potentially useful in adults with AN.

DISCUSSION

To date, evidence suggests that the safest and most effective strategy to improve bone health in AN is normalization of weight with restoration of menses. Pharmacotherapies that show promise include physiologic estradiol replacement (as the transdermal estradiol patch), and in adults, bisphosphonates. Further studies are necessary to determine the best strategies to normalize BMD in AN.

Anorexia Nervosa and Its Associated Endocrinopathy in Young People

Anorexia nervosa (AN) is a condition of severe undernutrition associated with adaptive changes in many endocrine axes. These changes include hypogonadotropic hypogonadism, acquired growth hormone resistance with low insulin-like growth factor 1 (IGF-1) levels, hypercortisolemia, altered secretion of adipokines and appetite-regulating hormones, and low bone mineral density (BMD). Bone health is impaired subsequent to a low body mass index, decreased lean mass, and the endocrine changes described above. In addition to low areal BMD, AN is characterized by a decrease in volumetric BMD, changes in bone geometry, and reductions in strength estimates, leading to an increased risk for fracture. Weight restoration is essential for restoration of normal endocrine function; however, hypercortisolemia, high peptide YY levels, and ghrelin dynamics may not completely normalize. In some patients, hypogonadotropic hypogonadism persists despite weight restoration. Weight gain and menstrual recovery are critical for improving bone health in AN; however, residual deficits may persist. Physiologic estrogen replacement using transdermal, but not oral, estrogen increases bone accrual in adolescents with AN, while bisphosphonates improve BMD in adults. Recombinant human IGF-1 and teriparatide have been used in a few studies as bone anabolic therapies. More data are necessary to determine the optimal therapeutic strategies for low BMD in AN.

Influence of a fermented protein-fortified dairy product on serum insulin-like growth factor-I in women with anorexia nervosa: A randomized controlled trial

BACKGROUND & AIMS

Patients with anorexia nervosa (AN) have low serum IGF-I levels that may contribute to a lower bone mineral mass. We investigated the effects of a fermented, protein-fortified, dairy product on serum IGF-I levels in patients with AN during an in-hospital refeeding program.

METHODS

In this multicenter, randomized, double-blind, placebo-controlled, clinical trial conducted at 3 university hospitals and 3 private clinics in France and Switzerland, 62 women recently admitted with confirmed AN and with a baseline low serum IGF-I level were randomized to 2 daily isocaloric fresh cheese pots containing either 15 g/150 g or 3 g/150 g (controls) of protein for 4 weeks. The primary outcome was the change in IGF-I levels.

RESULTS

In the primary intention-to-treat analysis, mean serum IGF-I levels increased during the intervention phase from 22.9 ± 1.5 to 28.6 ± 1.3 nmol/L (means ± SEM) (+20.2%) in the intervention group and from 20.2 ± 1.2 to 25.7 ± 1.5 nmol/L (+16.8%) in controls. In a preplanned analysis of covariance with repeated measures, the between-group difference was close to statistical significance (P = 0.071). In a post-hoc mixed-regression model analysis, the difference was statistically significant (4.9 nmol/l increase; P = 0.003), as was the change of the ratio IGF-I/IGF-BP3 (P=0.004). There was no between-group difference in biochemical markers of bone turnover (osteocalcin, P1NP, CTX) or in serum parathyroid hormone level. Serum calcium levels slightly increased during the intervention phase in the higher protein group (P = 0.02). IGF-BP2 decreased significantly more in the intervention group during the follow up period at week 4 after supplements cessation (P = 0.019).

CONCLUSIONS

Intake of a fermented, protein-fortified, isocaloric dairy product during 4 weeks may slightly increase serum IGF-I levels in women with AN, without significant changes in bone turnover markers.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01823822 (www.clinicaltrials.gov).

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.

Management of Low Bone Mass in Female Athletes

As female athletic participation has increased, the positive effects of exercise on health have become evident. However, with this growth in sports activity, a set of health problems unique to the female athlete has emerged. The female athlete triad and its components can occur in females of all ages in every sport. The Female Athlete Triad poses serious health risks, both short and long term, to the overall well-being of affected individuals. Sustained low energy availability can impair health, causing many medical complications within the skeletal, endocrine, cardiovascular, reproductive, and central nervous systems. With the surge of females participating in athletics within the past 10 to 15 years, it is both conceivable and likely that the prevalence of this syndrome will continue to grow. Therefore, it is imperative that appropriate screening and diagnostic measures are enacted by a multidisciplinary team of health care providers, counselors, teachers, and dieticians in order to provide the proper care to affected athletes. Initial awareness should take place within the educational confines of elementary and high schools. Screening for female athletes exhibiting risk factors for the triad should also take place at the time of sports physicals. If one component of the triad is identified, the clinician should take the time to effectively workup the other. Treatment for each component of the triad includes both pharmacological and nonpharmacological measures, with emphasis placed upon increased energy availability and overall improved nutritional health. Using this all-encompassing type of approach, sports medicine practitioners should feel empowered to continue to promote the lifelong well-being of female athletes in the years to come.

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.

2014 Female Athlete Triad Coalition consensus statement on treatment and return to play of the female athlete triad: 1st International Conference held in San Francisco, CA, May 2012, and 2nd International Conference held in Indianapolis, IN, May 2013

The Female Athlete Triad is a medical condition often observed in physically active girls and women, and involves 3 components: (1) low energy availability with or without disordered eating, (2) menstrual dysfunction, and (3) low bone mineral density. Female athletes often present with 1 or more of the 3 Triad components, and an early intervention is essential to prevent its progression to serious endpoints that include clinical eating disorders, amenorrhea, and osteoporosis. This consensus statement represents a set of recommendations developed following the first (San Francisco, California) and second (Indianapolis, Indianna) International Symposia on the Female Athlete Triad. It is intended to provide clinical guidelines for physicians, athletic trainers, and other health care providers for the screening, diagnosis, and treatment of the Female Athlete Triad and to provide clear recommendations for return to play. The 2014 Female Athlete Triad Coalition Consensus Statement on Treatment and Return to Play of the Female Athlete Triad Expert Panel has proposed a risk stratification point system that takes into account magnitude of risk to assist the physician in decision-making regarding sport participation, clearance, and return to play. Guidelines are offered for clearance categories, management by a multidisciplinary team, and implementation of treatment contracts. This consensus paper has been endorsed by The Female Athlete Triad Coalition, an International Consortium of leading Triad researchers, physicians, and other health care professionals, the American College of Sports Medicine, and the American Medical Society for Sports Medicine.

Bone disease in anorexia nervosa

Anorexia nervosa is a serious psychiatric disorder accompanied by high morbidity and mortality. It is characterized by emaciation due to self-starvation and displays a unique hormonal profile. Alterations in gonadal axis, growth hormone resistance with low insulin-like growth factor I levels, hypercortisolemia and low triiodothyronine levels are almost universally present and constitute an adaptive response to malnutrition. Bone metabolism is likewise affected resulting in low bone mineral density, reduced bone accrual and increased fracture risk. Skeletal deficits often persist even after recovery from the disease with serious implications for future skeletal health. The pathogenetic mechanisms underlying bone disease are quite complicated and treatment is a particularly challenging task.

Female athlete triad and its components: toward improved screening and management

As female athletic participation has increased, the positive effects of exercise on health have become evident. However, with this growth in sports activity, a set of health problems unique to the female athlete has emerged. The female athlete triad as first described in 1992 by the American College of Sports Medicine consisted of disordered eating, amenorrhea, and osteoporosis; the definition was updated in 2007 to include a spectrum of dysfunction related to energy availability, menstrual function, and bone mineral density. For this review, a comprehensive search of databases-MEDLINE In-Process & Other Non-Indexed Citations, MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and Scopus, from earliest inclusive dates to January 2013-was conducted by an experienced librarian with input from the authors. Controlled vocabulary supplemented with keywords such as female athlete triad, amenorrhea, oligomenorrhea, fracture, osteopenia, osteoporosis, bone disease, anorexia, bulimia, disordered eating, low energy availability was used to search for articles on female athlete triad. Articles addressing the prevalence, screening, and management of the female athlete triad were selected for inclusion in the review. This article reviews the current definitions of the triad components, epidemiology, pathophysiology, and recommended screening and management guidelines. The lack of efficacy of current screening of athletes is highlighted. Low energy availablity, from either dietary restriction or increased expenditure, plays a pivotal role in development of the triad. Athletes involved in "lean sports" (those that emphasize weight categories or aesthetics, such as ballet, gymnastics, or endurance running) are at highest risk. Treatment is centered on restoring energy availability to reverse adverse changes in the metabolic milieu. Prevention and early recognition of triad disorders are crucial to ensure timely intervention. Caregivers and physicians of female athletes must remain vigilant in education, recognition, and treatment of athletes at risk.

A case report of recovery of menstrual function following a nutritional intervention in two exercising women with amenorrhea of varying duration

Increasing caloric intake is a promising treatment for exercise-associated amenorrhea, but strategies have not been fully explored. The purpose of this case report was to compare and contrast the responses of two exercising women with amenorrhea of varying duration to an intervention of increased energy intake. Two exercising women with amenorrhea of short (3 months) and long (11 months) duration were chosen to demonstrate the impact of increased caloric intake on recovery of menstrual function and bone health. Repeated measures of dietary intake, eating behavior, body weight, body composition, bone mineral density, resting energy expenditure, exercise volume, serum metabolic hormones and markers of bone turnover, and daily urinary metabolites were obtained. Participant 1 was 19 years old and had a body mass index (BMI) of 20.4 kg/m² at baseline. She increased caloric intake by 276 kcal/day (1,155 kJ/day, 13%), on average, during the intervention, and her body mass increased by 4.2 kg (8%). Participant 2 was 24 years old and had a BMI of 19.7 kg/m². She increased caloric intake by 1,881 kcal/day (7,870 kJ/day, 27%) and increased body mass by 2.8 kg (5%). Resting energy expenditure, triiodothyronine, and leptin increased; whereas, ghrelin decreased in both women. Resumption of menses occurred 23 and 74 days into the intervention for the women with short-term and long-term amenorrhea, respectively. The onset of ovulation and regular cycles corresponded with changes in body weight. Recovery of menses coincided closely with increases in caloric intake, weight gain, and improvements in the metabolic environment; however, the nature of restoration of menstrual function differed between the women with short-term versus long-term amenorrhea.

Bone metabolism in anorexia nervosa: molecular pathways and current treatment modalities

Eating disorders are associated with a multitude of metabolic abnormalities which are known to adversely affect bone metabolism and structure. We aimed to comprehensively review the literature on the effects of eating disorders, particularly anorexia nervosa (AN), on bone metabolism, bone mineral density (BMD), and fracture incidence. Furthermore, we aimed to highlight the risk factors and potential management strategies for patients with eating disorders and low BMD. We searched the MEDLINE/OVID (1950-July 2011) and EMBASE (1980-July 2011) databases, focussing on in vitro and in vivo studies of the effects of eating disorders on bone metabolism, bone mineral density, and fracture incidence. Low levels of estrogen, testosterone, dehydroepiandrosterone, insulin-like growth factor-1 (IGF-1), and leptin, and high levels of cortisol, ghrelin, and peptide YY (PYY) are thought to contribute to the 'uncoupling' of bone turnover in patients with active AN, leading to increased bone resorption in comparison to bone formation. Over time, this results in a high prevalence and profound degree of site-specific BMD loss in women with AN, thereby increasing fracture risk. Weight recovery and increasing BMI positively correlate with levels of IGF-1 and leptin, normalisation in the levels of cortisol, as well as markers of bone formation and resorption in both adolescent and adult patients with AN. The only treatments which have shown promise in reversing the BMD loss associated with AN include: physiologic dose transdermal and oral estrogen, recombinant human IGF-1 alone or in combination with the oral contraceptive pill, and bisphosphonate therapy.

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.

Body mass, training, menses, and bone in adolescent runners: a 3-yr follow-up

Endurance runners with low bone mass during adolescence may risk attaining a low peak bone mineral density (BMD) in adulthood. Alternatively, they may mature late and undergo delayed bone mineral accumulation.

PURPOSE

The purpose of this study was to evaluate 40 adolescent runners (aged 15.9 ± 0.2 yr) at two time points, approximately 3 yr apart, to assess bone mass status and identify variables associated with bone mass change.

METHODS

Follow-up measures included a questionnaire to assess menstrual status, training, and sports participation history, height and weight, and a dual-energy x-ray absorptiometry scan to assess total body, total hip, and lumbar spine BMD, bone mineral content (BMC), BMD z-score, and body composition. We used -1 and -2 BMD z-score cutoffs to categorize runners with low bone mass.

RESULTS

Eighty-seven percent of girls with low BMD at baseline had low BMD at the follow-up. Girls with low compared with normal baseline BMD had lower follow-up adjusted total body (2220.4 ± 65.8 vs 2793.1 ± 68.2 g, P < 0.001), total hip (27.0 ± 1 vs 33.9 ± 1.0 g, P < 0.05), and lumbar spine (47.8 ± 2.0 vs 66.3 ± 2.2 g, P < 0.001) BMC values. Variables related to 3-yr training volume, menstrual function, age, developmental stage, and change in body mass explained 29%-54% of the variability in BMC change.

CONCLUSIONS

The majority of adolescent runners with low BMD at baseline had low BMD after a 3-yr follow-up. Our observations suggest that "catch-up" accrual may be difficult and, thus, emphasize the importance of gaining adequate bone mineral during the early adolescent years.

Caloric restriction leads to high marrow adiposity and low bone mass in growing mice

The effects of caloric restriction (CR) on the skeleton are well studied in adult rodents and include lower cortical bone mass but higher trabecular bone volume. Much less is known about how CR affects bone mass in young, rapidly growing animals. This is an important problem because low caloric intake during skeletal acquisition in humans, as in anorexia nervosa, is associated with low bone mass, increased fracture risk, and osteoporosis in adulthood. To explore this question, we tested the effect of caloric restriction on bone mass and microarchitecture during rapid skeletal growth in young mice. At 3 weeks of age, we weaned male C57Bl/6J mice onto 30% caloric restriction (10% kcal/fat) or normal diet (10% kcal/fat). Outcomes at 6 (n = 4/group) and 12 weeks of age (n = 8/group) included body mass, femur length, serum leptin and insulin-like growth factor 1 (IGF-1) values, whole-body bone mineral density (WBBMD, g/cm(2)), cortical and trabecular bone architecture at the midshaft and distal femur, bone formation and cellularity, and marrow fat measurement. Compared with the normal diet, CR mice had 52% and 88% lower serum leptin and 33% and 39% lower serum IGF-1 at 6 and 12 weeks of age (p < .05 for all). CR mice were smaller, with lower bone mineral density, trabecular, and cortical bone properties. Bone-formation indices were lower, whereas bone-resorption indices were higher (p < .01 for all) in CR versus normal diet mice. Despite having lower percent of body fat, bone marrow adiposity was elevated dramatically in CR versus normal diet mice (p < .05). Thus we conclude that caloric restriction in young, growing mice is associated with impaired skeletal acquisition, low leptin and IGF-1 levels, and high marrow adiposity. These results support the hypothesis that caloric restriction during rapid skeletal growth is deleterious to cortical and trabecular bone mass and architecture, in contrast to potential skeletal benefits of CR in aging animals.

Osteoporosis in anorexia nervosa

Anorexia nervosa is a condition associated with reduced bone mass and increased bone fragility, for which there is no known effective treatment. Anorexia nervosa usually has its onset during adolescence, the critical time when peak bone mass is accrued. Low bone mass is caused by reduced bone formation, as well as accelerated bone resorption. The etiology is multifactorial and includes poor nutrition, low bodyweight, sex hormone deficiency and hypercortisolism. Weight gain and resumption of menses is accompanied by some improvement in bone mass, but may not restore it to normal levels. Oral estrogen-replacement therapy is not effective in increasing bone mass in this disorder. The bisphosphonates, used in conjunction with nutritional rehabilitation and weight gain, have shown promise, but concerns about safety have limited their use. The aim of this article is to highlight recent recommendations regarding the assessment of fracture risk in children and adolescents, summarize the evidence for low bone mass and increased fracture risk in anorexia nervosa, and discuss approaches to the management of low bone mass in this disorder.

Cross-sectional evidence of suppressed bone mineral accrual among female adolescent runners

We aimed to evaluate patterns of bone mineral accrual among a cross-sectional sample of female adolescent runners and girls participating in a nonendurance running sport. One-hundred and eighty-three interscholastic competitive female athletes (age 16.0 +/- 0.1 years), 93 endurance runners and 90 nonrunners, completed a menstrual and sports history questionnaire, had their height and weight measured, and underwent a dual-energy X-ray absorptiometry scan for the measurements of body composition and bone mass. For the majority of analyses, the girls were separated into four groups according to their age (13 to 14 years, 15 years, 16 years, and 17 to 18 years). Runners' height, weight, body mass index (BMI), percent body fat, lean tissue mass, number of menstrual cycles in the past year, and months of participation in a non-lean-build/variable-impact-loading sport were significantly lower than mean values for nonrunners. Although bone mass rose at all sites in the nonrunners between the ages of 13 to 14 years and 17 to 18 years, no such increase was noted in the runners. Runners compared with nonrunners exhibited significantly lower body weight and height-adjusted total body and lumbar spine bone mineral content (BMC) values and lower bone mineral density (BMD) Z-score values among the older (16 years and/or 17 to 18 years) but not younger (13 to 14 years and/or 15 years) age groups. These findings suggest that the runners, in contrast to the nonrunners, exhibited a suppressed bone mineral accrual pattern, which supports the notion that female adolescent endurance runners may be at risk for inadequate bone mass gains and thus a low peak BMD.

Bone loss without the loss of bone mineral material? A new perspective on anorexia nervosa

Since the advent on non-invasive in vivo clinical bone densitometry, investigators have reported that regional bone mineral material loss accompanies the onset and continuance of anorexia nervosa (AN). Initial single-energy photon absorptiometric (SPA) studies were followed by a succession of dual-energy X-ray absorptiometric (DXA) investigations, and a few single-energy quantitative computer assisted tomographic (SEQCT) bone densitometry vertebral measurements. Although most all DXA studies found a relatively small diminution (approximately 3%) of bone mineral material at lumbar vertebral and proximal femoral bone-sites of AN-afflicted adolescent girls and young women, these findings have been consensually interpreted and near-universally accepted as losses of actual bone mineral material accompanying AN. It has also been claimed by some that about 50% of those beset by AN while still young adolescents were osteoporotic. Nonetheless, over the last intervening 2 decades of these studies, no specific underlying direct bone-biological causal link between AN and trabecular bone material loss has yet been uncovered. The present exposition shows that in vivo SPA, DXA, and SEQCT measurements of bone mineral material losses do not constitute evidence of actual loss of bone material, and that the attribution of osteopenia and osteoporosis to AN-afflicted younger adolescent girls is not sustainable. Rather, the full gamut of these reported bone material "losses" can be accounted for by the already well-documented AN-induced changes in the anthropometrics and compositional mixes of extra-osseous soft tissues (primarily in a very noticeable reduction of extra-skeletal fat) and intra-osseous bone marrow yellowing (marrow hypoplasia and marrow cell necrosis). These changes in soft tissue compositions and anthropometrics alone have been shown to be sufficient to cause in vivo SPA, DXA, and SEQCT to systematically mis-estimate true bone material density and erroneously register changes in bone mineral content, even when no actual changes in bone mineral material have occurred. As a result, it is seen that in vivo bone densitometry methodologies have not demonstrated that AN induces actual loss of bone mineral material. It is also demonstrated that DXA and SEQCT bone density measurements of predominantly trabecular bone-sites cannot be relied upon as gauges of heightened propensity for early (or late) osteoporotic development.

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.

Total and regional bone mineral content in healthy Spanish subjects by dual-energy X-ray absorptiometry

DESIGN

This is an observational cross-sectional study.

OBJECTIVE

The aim of the present study was to describe and analyze patterns of change in total and regional bone mineral content in relation to age and gender in a sedentary Spanish sample population (from the Community of Madrid). The age range of the sample population was from birth to 80 years.

MATERIALS AND METHODS

One thousand one hundred twenty healthy subjects were recruited and divided into 16 groups according to age. Each subject underwent whole-body densitometry using dual-energy X-ray absorptiometry. An analysis was made of the amount of bone mineral content (BMC) in the whole body and in different regions: the head, trunk, upper limbs, and lower limbs.

RESULTS

Gender differences in mean values for upper limbs and lower limbs are statistically significant between 16 and 70 years of age. For the head and trunk, the mean BMC values show the most significant gender differences between 16 and 25 years of age (p <or= 0.001). Total bone mineral content (TBMC) and TBMC-to-height ratio show significant gender differences between 16 and 70 years of age. In females, TBMC values increase up to 20 years of age and in males up to 25 years of age.

CONCLUSION

We have determined an evolutionary normal pattern of bone mineral content in urban Spanish people.

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.

Strategies to reverse bone loss in women with functional hypothalamic amenorrhea: a systematic review of the literature

Functional hypothalamic amenorrhea (FHA) impairs the attainment of peak bone mass and as such can increase the risk of fractures later in life. To document available treatment strategies, we conducted a systematic review of the literature. We report that hormonal therapies have limited effectiveness in increasing bone mass, whereas increased caloric intake resulting in weight gain and/or resumption of menses is an essential strategy for restoring bone mass in women with FHA.

INTRODUCTION

Women with functional hypothalamic amenorrhea (FHA) may not achieve peak bone mass (PBM), which increases the risk of stress fractures, and may increase the risk of osteoporotic fractures in later life.

METHODS

To identify effective treatment strategies for women with FHA, we conducted a systematic review of the literature. We included randomized controlled trials (RCTs), cross-sectional studies, and case studies that reported on the effects of pharmacological and non-pharmacological interventions on bone mineral density (BMD) or bone turnover in women with FHA.

RESULTS

Most published studies (n=26) were designed to treat the hormonal abnormalities observed in women with FHA (such as low estrogen, leptin, insulin-like growth factor-1, and DHEA); however none of these treatments demonstrated consistent improvements in BMD. Therapies containing an estrogen given for 8-24 months resulted in variable improvements (1.0-19.0%) in BMD, but failed to restore bone mass to that of age-matched controls. Three studies reported on the use of bisphosphonates (3-12 months) in anorexic women, which appear to have limited effectiveness to improve BMD compared to nutritional treatments. Another three investigations showed no improvements in BMD after androgen therapy (DHEA and testosterone) in anorexic women. In contrast, reports (n=9) describing an increase in caloric intake that results in weight gain and/or the resumption of menses reported a 1.1-16.9% increase in BMD concomitant with an improvement in bone formation and reduction in bone resorption markers.

CONCLUSIONS

Our literature review indicates that the most successful, and indeed essential strategy for improving BMD in women with FHA is to increase caloric intake such that body mass is increased and there is a resumption of menses. Further long-term studies to determine the persistence of this effect and to determine the effects of this and other strategies on fracture risk are needed.

Weight gain and restoration of menses as predictors of bone mineral density change in adolescent girls with anorexia nervosa-1

CONTEXT

Adolescents with anorexia nervosa (AN) have low bone mineral density. However, the effect of disease recovery, first, on bone density measures assessed using the Molgaard approach, which differentiates between reported low bone density resulting from short bones (based on height Z-scores) and that resulting from thin bones [based on measures of bone area (BA) for height] or light bones [based on measures of bone mineral content (BMC) for BA]; and second, on height-adjusted bone density measures, has not been well characterized. We hypothesized that menstrual recovery and weight gain (> or =10% increase in body mass index) would predict an increase in these measures of bone density.

METHODS

In a prospective observational study, lumbar and whole-body (WB) bone density was measured at 0, 6, and 12 months in 34 AN girls aged 12-18 yr and 33 controls. Using Ward's modification of the Molgaard approach, we determined measures of BMC for BA and BA for height at the lumbar spine and WB and also determined spine bone mineral apparent density and WB BMC adjusted for height.

RESULTS

Girls with AN had lower spine BMC for BA Z-scores (P = 0.0009), and lower WB BA for height Z (P < 0.0001), compared with controls. Menstrual recovery and weight gain in AN (AN-recovered) (median 9 months) resulted in a stabilization of BMD measures, whereas BMD continued to decrease in AN who did not gain weight and recover menses (AN-not recovered). AN-recovered also predicted greater increases in spine BMC for BA and WB BA for height, compared with AN-not recovered (P < 0.05).

CONCLUSIONS

Even short-term weight gain with menstrual recovery is associated with a stabilization of BMD measures.

Cholinesterase and other serum liver enzymes in underweight outpatients with eating disorders

OBJECTIVE

The present study aimed to evaluate serum liver enzymes in underweight outpatients with anorexia nervosa (A-NERV) or eating disorders not otherwise specified (EDNOS).

METHOD

Serum alanine amino transferase (ALT), aspartate amino transferase (AST), lactic dehydrogenase (LDH), gamma glutamyl transferase (GGT), alkaline phosphatase (ALP), and cholinesterase (CHE) were determined in 97 patients with A-NERV, 66 patients with EDNOS, and 56 controls.

RESULTS

In the A-NERV group AST, LDH, and GGT were higher, as compared with controls, and inversely related to weight, while ALP and CHE were lower. AST and GGT increased and CHE decreased in patients with EDNOS. Hypertransaminasemia occurred in 14.4 and 15.2%, and low CHE in 29.9% of the A-NERV group and 13.6% and EDNOS group, respectively. Three or more abnormalities were found in 9.3% of patients with A-NERV and 7.5% of those with EDNOS.

CONCLUSION

Abnormalities in serum liver enzymes are common in outpatients with eating disorders plus underweight. CHE might be considered as a marker of the effects of primary malnutrition on liver function.

A study of bone density change in patients with anorexia nervosa

In patients with anorexia nervosa (AN) several factors combine to cause osteoporosis, and the risk of osteoporosis increases with chronicity of illness. The authors carried out a follow-up study in patients who attended the Eating Disorders department of the Hospital de Santa Maria. The average follow-up period was of 7.6 years. Fifteen patients were included. Patients answered clinical history questions and underwent neck of femur and spine densitometry. The most important variable with negative correlations to bone recovery was disease duration. A positive correlation between bone recovery and time since the first menstrual cycle post-amenorrhea was also found. However, AN is a condition in which once weight improves and menstrual cycles become regular, severe damage to bone structure is still likely to be maintained.

Regional skeletal bone deficit in female adolescents with anorexia nervosa: influence of the degree of malnutrition and weight recovery in a two year longitudinal study

AIM

To analyze changes in bone mineral density (BMD) and the effect of weight recovery on the restoration of bone mass in adolescent females with anorexia nervosa (AN) with moderate malnutrition.

STUDY DESIGN

We evaluated lumbar and femoral BMD in 27 females with restrictive AN with malnutrition and amenorrhea for over (M+PA) or less than (M+SA) one year and 12 with normal nutrition and amenorrhea for over one year (N+PA) followed for 24 months.

RESULTS

BMI remained below -1.5 SD in M+PA and increased at 24 months in M+SA. M+PA had low lumbar and femoral neck BMD at diagnosis, decreasing at 24 months. Lumbar BMD in N+PA and M+SA was reduced, with an increase in M+SA at 24 months.

CONCLUSIONS

Moderate malnutrition in AN induces loss of bone mass at the lumbar and femoral levels. Weight gain and resumption of menses increases bone mass, especially in the lumbar spine.

The Female Athlete Triad

The female athlete triad (Triad) refers to the interrelationships among energy availability, menstrual function, and bone mineral density, which may have clinical manifestations including eating disorders, functional hypothalamic amenorrhea, and osteoporosis. With proper nutrition, these same relationships promote robust health. Athletes are distributed along a spectrum between health and disease, and those at the pathological end may not exhibit all these clinical conditions simultaneously. Energy availability is defined as dietary energy intake minus exercise energy expenditure. Low energy availability appears to be the factor that impairs reproductive and skeletal health in the Triad, and it may be inadvertent, intentional, or psychopathological. Most effects appear to occur below an energy availability of 30 kcal.kg(-1) of fat-free mass per day. Restrictive eating behaviors practiced by girls and women in sports or physical activities that emphasize leanness are of special concern. For prevention and early intervention, education of athletes, parents, coaches, trainers, judges, and administrators is a priority. Athletes should be assessed for the Triad at the preparticipation physical and/or annual health screening exam, and whenever an athlete presents with any of the Triad's clinical conditions. Sport administrators should also consider rule changes to discourage unhealthy weight loss practices. A multidisciplinary treatment team should include a physician or other health-care professional, a registered dietitian, and, for athletes with eating disorders, a mental health practitioner. Additional valuable team members may include a certified athletic trainer, an exercise physiologist, and the athlete's coach, parents and other family members. The first aim of treatment for any Triad component is to increase energy availability by increasing energy intake and/or reducing exercise energy expenditure. Nutrition counseling and monitoring are sufficient interventions for many athletes, but eating disorders warrant psychotherapy. Athletes with eating disorders should be required to meet established criteria to continue exercising, and their training and competition may need to be modified. No pharmacological agent adequately restores bone loss or corrects metabolic abnormalities that impair health and performance in athletes with functional hypothalamic 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.

Skeletal status and laboratory investigations in adolescent girls with anorexia nervosa

To our knowledge anorexia nervosa (AN) adversely influences bone density, but whether qualitative characteristics of bone are also affected is not known. For this reason we investigated prospectively the changes in skeletal status in a population of 18 adolescent girls with AN aged 11.5-18.1 years (mean 15.9+/-1.9 years) using both dual-photon X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) measurements, bone turnover markers (osteocalcin, bone alkaline phosphatase - bALP, carboxy-terminal cross-linked telopeptide of type I collagen - ICTP), and laboratory investigations (serum total and ionised calcium, serum phosphate, urine calcium/creatinine ratio, luteinizing hormone - LH, follicle-stimulating hormone - FSH, estradiol). Measurements of bone mineral density at the spine (s-BMD) and total body (TB-BMD) and amplitude-dependent speed of sound (Ad-SOS) of the hand phalanges were performed at baseline, 7.8+/-2.4 and 19.4+/-5.6 months of follow-up. The mean values of TB-BMD, s-BMD and Ad-SOS measurements did not change during the period of observation. The mean Z-scores for TB-BMD and Ad-SOS were significantly lower after 19.4 months of observation vs. baseline (-1.06+/-1.00 vs. -0.67+/-0.98 vs. and -0.50+/-0.88 vs. 0.26+/-1.75, respectively). Z-scores for s-BMD decreased non-significantly (p=0.08). Among bone turnover markers, we observed a significant increase in bALP and a non-significant increase in osteocalcin serum concentrations which were below normal ranges for age, sex and Tanner stage at baseline. High baseline serum ICTP concentration decreased non-significantly, reaching normal ranges during the observation. We conclude that anorexia nervosa seriously affects skeletal status in adolescent girls. Bone turnover markers analysed together with densitometric parameters suggest that AN influences both bone formation and resorption processes. QUS measurements at hand phalanges may be an appropriate method in the evaluation of skeletal status in patients with AN.

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.

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

INTRODUCTION

In anorexia nervosa (AN) patients osteoporosis occurs within a framework of multiple hormonal abnormalities as a result of bone turnover uncoupling, with decreased bone formation and increased bone resorption. The aim of study was to evaluate the hormonal and nutritional relationships with both of these bone remodeling compartments and their eventual modifications with age.

PATIENTS AND MEASUREMENTS

In a cohort of 115 AN patients (mean BMI:14.6 kg/m2) that included 60 mature adolescents (age: 15.5-20 years) and 55 adult women (age: 20-37 years) and in 28 age-matched controls (12 mature adolescents and 16 adults) we assessed: bone markers [serum osteocalcin, skeletal alkaline phosphatase (sALP), C-telopeptide of type I collagen (sCTX) and tartrate-resistant acid phosphatase type 5b (TRAP 5b)], nutritional markers [ body mass index (BMI, fat and lean mass), hormones (free tri-iodothyronine (T3), free T4, thyroid stimulating hormone (TSH), luteinizing hormone (LH), follicle stimulating hormone (FSH), 17 beta estradiol, free testosterone index (FTI), dehydroepiandrosterone (DHEAS), insulin-like growth factor 1 (IGF-1), growth hormone (GH) and cortisol], plasma methoxyamines (metanephrine and normetanephrine) and calcium metabolism parameters [parathyroid hormone (PTH), Ca, vitamin D3].

RESULTS

Osteocalcin reached similar low levels in both AN age subgroups. sCTX levels were found to be elevated in all AN subjects and higher in mature adolescents than in adult AN (11,567+/-895 vs. 8976+/-805 pmol/l, p<0.05). sALP was significantly lower only in mature adolescent AN patients, while there were no significant differences in the levels of TRAP 5b between AN patients and age-matched control groups. Osteocalcin correlated with sCTX in the control subjects (r=0.65) but not in the AN patients, suggesting the independent regulation of these markers in AN patients. Osteocalcin levels strongly correlated with freeT3, IGF-I, 17 beta estradiol and cortisol, while sCTX correlated with IGF-I, GH and cortisol in both age subgroups of the AN patients. Other hormones or nutritional parameters displayed age-related correlations with bone markers, leading to different stepwise regression models for each age interval. In mature adolescent AN patients, up to 54% of the osteocalcin variance was due to BMI, cortisol and 17 beta estradiol, while 54% of the sCTX variance was determined by GH. In adult subjects, freeT3 and IGF-I accounted for 64% of osteocalcin variance, while 65% of the sCTX variance was due to GH, FTI and methoxyamines.

CONCLUSIONS

We suggest a more complex mechanism of AN bone uncoupling that includes not only "classical" influence elements like cortisol, IGF-I, GH or 17 beta estradiol but also freeT3, catecholamines and a "direct" hormone-independent impact of denutrition. Continuous changes of these influences with age should be considered within the therapeutic approach to AN bone loss.