Predicting Menstrual Recovery in Adolescents With Anorexia Nervosa Using Body Fat Percent Estimated by Bioimpedance Analysis

[Consenso del grupo de trabajo de los trastornos de la conducta alimentaria de SENPE (GTTCA-SENPE). Evaluación y tratamiento médico-nutricional en la anorexia nerviosa. Actualización 2023]

Anorexia nervosa (AN) is a multifactorial disorder. A possible role of the social network and the gut microbiota in pathogenesis has been added. Exogenous shocks such as the COVID19 pandemic have had a negative impact on patients with AN. The potential medical and nutritional impact of malnutrition and/or compensatory behaviors gives rise to a complex disease with a wide range of severity, the management of which requires a multidisciplinary team with a high level of subject matter expertise. Coordination between levels of care is necessary as well as understanding how to transition the patient from pediatric to adult care is essential. A proper clinical evaluation can detect possible complications, as well as establish the organic risk of the patient. This allows caregivers to tailor the medical-nutritional treatment for each patient. Reestablishing adequate nutritional behaviors is a fundamental pillar of treatment in AN. The design of a personalized nutritional treatment and education program is necessary for this purpose. Depending on the clinical severity, artificial nutrition may be necessary. Although the decision regarding the level of care necessary at diagnosis or during follow-up depends on a number of factors (awareness of the disease, medical stability, complications, suicidal risk, outpatient treatment failure, psychosocial context, etc.), outpatient treatment is the most frequent and most preferred choice. However, more intensive care (total or partial hospitalization) may be necessary in certain cases. In severely malnourished patients, the appearance of refeeding syndrome should be prevented during renourishment. The presence of AN in certain situations (pregnancy, vegetarianism, type 1 diabetes mellitus) requires specific care. Physical activity in these patients must also be addressed correctly.

Body composition and nutritional status changes in adolescents with anorexia nervosa

INTRODUCTION

Nutritional status assessment in anorexia nervosa (AN) includes the evaluation and monitoring of body composition throughout the treatment period. The gold standard for the study of body composition is dual-energy X-ray absorptiometry (DEXA), although electrical bioimpedance (BIA) is a more accessible, cheaper and faster method that does not involve exposure to radiation.

MATERIAL AND METHODS

We recruited 33 female adolescents with AN (age, 11.7-16.3 years) by consecutive sampling. We collected data on clinical, anthropometric and laboratory variables. Patients were assessed with BIA and DEXA at inclusion in the study and at the end of the study, with a mean duration of follow-up of 1 year, during the nutritional rehabilitation phase.

RESULTS

There was significant improvement in nutritional status, reflected by the body composition obtained by anthropometric measurements and BIA. The phase angle increased significantly during the follow-up. Greater weight loss was associated with the presence of secondary amenorrhoea and decreased bone mineral density in the spine.

CONCLUSIONS

Electrical BIA is a useful tool for assessment and monitoring of nutritional status in paediatric patients with AN. Dual-energy X-ray absorptiometry continues to be essential to assess bone mineral density. The role of hormones such as leptin remains to be elucidated.

Endocrinology of Underweight and Anorexia Nervosa

More than any other mental illness, the course, prognosis, and therapy of anorexia nervosa are shaped by the physical changes associated with being underweight. This article provides an overview of the endocrine changes associated with malnutrition and underweight. This overview serves as a basis for understanding the other articles in this special issue, which deal with the health risks associated with being underweight. In this context, the differences between underweight in anorexia nervosa and in constitutional thinness are of particular importance in assessing the impact of intentional weight loss. In this context, the regulation of hunger and satiety deserves special interest, as this is the area in which the intentional influence on body weight comes into play. Clinical consequences on, for example, fertility, bone metabolism, the homeostasis of, for example, serum glucose levels, or body temperature have been observed for a long time; nonetheless, the medical responses, apart from vitamin supplementations and advice to gain weight, are still limited. Therefore, emphasis was placed on the potential improvement of outcomes through the administration of central or peripheral hormones. Studies were identified on PubMed via a selection of relevant keywords; original texts that were cited in reviews were studied where it was advantageous. This review found some promising data on bone health and the administration of transdermal oestrogen, which is not yet widely used, as well as distinct hormonal markers to differentiate between CT and AN. We concluded that the continuous efforts to investigate the role of endocrinology in underweight and/or anorexia nervosa lead to outcome benefits and that more and higher-powered studies are needed.

Recovery of menses after functional hypothalamic amenorrhoea: if, when and why

BACKGROUND

Prolonged amenorrhoea occurs as a consequence of functional hypothalamic amenorrhoea (FHA) which is most often induced by weight loss, vigorous exercise or emotional stress. Unfortunately, removal of these triggers does not always result in the return of menses. The prevalence and conditions underlying the timing of return of menses vary strongly and some women report amenorrhoea several years after having achieved and maintained normal weight and/or energy balance. A better understanding of these factors would also allow improved counselling in the context of infertility. Although BMI, percentage body fat and hormonal parameters are known to be involved in the initiation of the menstrual cycle, their role in the physiology of return of menses is currently poorly understood. We summarise here the current knowledge on the epidemiology and physiology of return of menses.

OBJECTIVE AND RATIONALE

The aim of this review was to provide an overview of (i) factors determining the recovery of menses and its timing, (ii) how such factors may exert their physiological effects and (iii) whether there are useful therapeutic options to induce recovery.

SEARCH METHODS

We searched articles published in English, French or German language containing keywords related to return of menses after FHA published in PubMed between 1966 and February 2020. Manuscripts reporting data on either the epidemiology or the physiology of recovery of menses were included and bibliographies were reviewed for further relevant literature. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) criteria served to assess quality of observational studies.

OUTCOMES

Few studies investigate return of menses and most of them have serious qualitative and methodological limitations. These include (i) the lack of precise definitions for FHA or resumption of menses, (ii) the use of short observation periods with unsatisfactory descriptions and (iii) the inclusion of poorly characterised small study groups. The comparison of studies is further hampered by very inhomogeneous study designs. Consequently, the exact prevalence of resumption of menses after FHA is unknown. Also, the timepoint of return of menses varies strongly and reliable prediction models are lacking. While weight, body fat and energy availability are associated with the return of menses, psychological factors also have a strong impact on the menstrual cycle and on behaviour known to increase the risk of FHA. Drug therapies with metreleptin or naltrexone might represent further opportunities to increase the chances of return of menses, but these require further evaluation.

WIDER IMPLICATIONS

Although knowledge on the physiology of return of menses is presently rudimentary, the available data indicate the importance of BMI/weight (gain), energy balance and mental health. The physiological processes and genetics underlying the impact of these factors on the return of menses require further research. Larger prospective studies are necessary to identify clinical parameters for accurate prediction of return of menses as well as reliable therapeutic options.

The effect of underweight on female and male reproduction

Chronic energy deficiency can impair the hypothalamic-pituitary-gonadal (HPG) axis and lead to hypothalamic anovulation in underweight women. This review presents the syndromes related to underweight status that are associated with infertility, summarizes the underlying mechanisms, and reviews the available treatment options. Eating disorders, such as anorexia nervosa (AN), constitute the most common cause of infertility in underweight women, who, in addition, experience miscarriages, and sexual dysfunction. The relative energy deficiency in sports (RED-S; former terminology: athlete's triad) involves menstrual dysfunction due to low energy availability, which results in anovulation. Moreover, lipodystrophies, malnutrition, starvation, systematic illnesses (malignancies, endocrinopathies, infectious diseases, advanced chronic diseases, neurologic illnesses), and the utilization of drugs can cause excessive weight loss. They may result in fertility problems due to the loss of adipose tissue and the subsequent hormonal disturbances. Each of these conditions requires multidisciplinary management. Nutritional counseling should target the restoration of energy balance by increasing intake and reducing output. Medical treatment, recommended only for patients who did not respond to standard treatment, may include antipsychotics, antidepressants, or leptin administration. Finally, psychiatric treatment is considered an integral part of the standard treatment.

IS BODY FAT PERCENTAGE A GOOD PREDICTOR OF MENSTRUAL RECOVERY IN FEMALES WITH ANOREXIA NERVOSA AFTER WEIGHT RESTORATION? A SYSTEMATIC REVIEW AND EXPLORATORY AND SELECTIVE META-ANALYSIS

The resumption of menses (ROM) is an important outcome in anorexia nervosa treatment and is considered as a sign of recovery. Identification of relevant factors in its prediction is important in clinical practice. Therefore we aimed to conduct a systematic review and exploratory meta-analysis of the association between total body fat percentage (%BF) and ROM after weight restoration in adolescents and young adults with anorexia nervosa. The study was conducted by adhering to Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. Data were collated using meta-analysis and a narrative approach. Of the 604 articles retrieved, only seven studies comprising a total of 366 adolescent and young adult females with anorexia nervosa met the inclusion criteria and were reviewed, and preliminary results revealed three main findings. Firstly, patients who resumed their menstrual cycle had a significantly higher mean %BF when compared to those who did not, an overall effect confirmed by the meta-analysis (SMD: 3.74, 95% CI: 2.26-5.22). Secondly, %BF was found to be an independent predictor of the ROM in this population and an increase of only one unit of %BF can increase the odds of menstruation by ≈15-20%. Thirdly, despite the paucity of data, a cut-off point of %BF≈21was suggested as the minimum needed for ROM. In conclusion, a higher %BF seems to be associated with the ROM in weight-restored adolescent and young adult females with anorexia nervosa. Its assessment is important in a clinical setting, especially after complete weight restoration. The PROSPERO Registry - A systematic review and meta-analysis of the factors associated with the resumption of the menstrual cycle in females with anorexia nervosa after weight restoration (CRD42019111841).