Medical assessment of adolescent girls with eating disorders: an evaluation of symptoms and signs of starvation

Similarities and differences regarding acute anorexia nervosa and semi-starvation: does behavioral thermoregulation play a central role?

Objective

To clarify the association between acute anorexia nervosa (AN) and semi-starvation (SS) by focusing on similarities and differences in physiology, mood, and behavior.

Method

A comparison of published literature between these two groups.

Results

Both groups show similar hormonal and metabolic changes in response to caloric restriction and extreme weight loss (~25%). Associated changes result in a reduced body temperature (Tcore-low). Maintenance of body temperature within a specific range is crucial to survival. However, both groups cannot activate autonomic strategies to maintain their Tcore-low, such as increasing metabolic rate, constricting skin blood vessels, or shivering. Furthermore, Tcore-low increases the individuals' "coldness sensations" throughout the body, hence the frequent reports from ANs and SSs of "feeling cold." To eliminate these uncomfortable "coldness sensations" and, importantly, to maintain Tcore-low, ANs, and SSs "select" different thermoregulatory behavioral strategies. It is proposed that the primary differences between AN and SS, based on genetics, now manifest due to the "selection" of different thermo-regulatory behaviors. AN patients (ANs) "select" hyperactive behavior (HyAc), which increases internal metabolic heat and thus assists with maintaining Tcore-low; in harmony with hyperactive behavior is a lively mood. Also related to this elevated arousal pattern, ANs experience disrupted sleep. In contrast, SS individuals "select" a passive thermo-behavioral strategy, "shallow torpor," which includes reduced activity, resulting in energy conservation. In addition, this inactivity aids in the retention of generated metabolic heat. Corresponding to this lethargic behavior, SS individuals display a listless mood and increased sleep.

Conclusion

Initial similarities between the two are attributable to physiological changes related to extreme weight loss. Differences are most likely attributable to genetically programmed "selection" of alternate thermoregulatory strategies, primarily to maintain Tcore-low. However, if acute AN is prolonged and evolves into a chronic condition, AN will more closely align with starvation and more precisely reflect SS symptomology.

The Central Role of Hypothermia and Hyperactivity in Anorexia Nervosa: A Hypothesis

Typically, the development of anorexia nervosa (AN) is attributed to psycho-social causes. Several researchers have recently challenged this view and suggested that hypothermia and hyperactivity (HyAc) are central to AN. The following hypothesis will attempt to clarify their role in AN. Anorexia nervosa patients (ANs) have significantly lower core temperatures (T_core) compared to healthy controls (HCs). This reduced temperature represents a reset T_core that needs to be maintained. However, ANs cannot maintain this T_core due primarily to a reduced basal metabolic rate (BMR); BMR usually supplies heat to sustain T_core. Therefore, to generate the requisite heat, ANs revert to the behavioral-thermoregulatory strategy of HyAc. The majority of ANs (~89%) are reportedly HyAc. Surprisingly, engagement in HyAc is not motivated by a conscious awareness of low T_core, but rather by the innocuous sensation of "cold- hands" frequently reported by ANs. That is, local hand-thermoreceptors signal the brain to initiate HyAc, which boosts perfusion of the hands and alters the sensation of "cold-discomfort" to one of "comfort." This "rewarding" consequence encourages repetition/habit formation. Simultaneously, hyperactivity increases the availability of heat to assist with the preservation of T_core. Additionally, HyAc induces the synthesis of specific brain neuromodulators that suppress food intake and further promote HyAc; this outcome helps preserve low weight and perpetuates this vicious cycle. Based on this hypothesis and supported by rodent research, external heat availability should reduce the compulsion to be HyAc to thermoregulate. A reduction in HyAc should decrease the production of brain neuromodulators that suppress appetite. If verified, hopefully, this hypothesis will assist with the development of novel treatments to aid in the resolution of this intractable condition.

Medical Complications of Anorexia Nervosa and Bulimia Nervosa

Anorexia nervosa and bulimia nervosa are mental illnesses with associated complications affecting all body systems with arguably the highest mortality of all mental health disorders. A comprehensive medical evaluation is an essential first step in the treatment of anorexia nervosa and bulimia nervosa. Weight restoration and cessation of purging behaviors are often essential components in the management of medical complications of these illnesses.

Influence of premorbid BMI on clinical characteristics at presentation of adolescent girls with eating disorders

BACKGROUND

Considering the prevalence of obesity in society it can be expected that some adolescents with an eating disorder (ED) start weight loss from an overweight and present at a near-normal weight. Presently, the influence of premorbid BMI on clinical characteristics of adolescent girls presenting with an ED has ben studied.

METHOD

Premorbid growth charts were available for 275 postmenarcheal adolescent girls presenting with an ED (anorexia nervosa = 27, (subthreshold) bulimia nervosa = 9, restrictive EDNOS = 239). Initial assessment included measurement of weight and length, physical examination, blood sampling and administration of the Eating Disorder Examination-Questionnaire youth version (EDE-Q).

RESULTS

Despite greater weight loss girls with a high premorbid body mass index (BMI) had a higher BMI at presentation compared to those with a lower premorbid BMI. Although not underweight some presented with clinical and laboratory signs of starvation. These signs were related to not only low BMI but also to rapid and large weight loss. Their EDE-Q scores did not differ from those of girls who presented with an underweight.

CONCLUSION

Girls with a restrictive ED and premorbid overweight may present with a near-normal BMI. They can nevertheless be medically compromised and have eating disturbed cognitions at the level of underweight girls. They should not be regarded as having a less severe ED but merit full assessment and a start of treatment.

THE ENDOCRINOPATHIES OF MALE ANOREXIA NERVOSA: CASE SERIES

OBJECTIVE

Anorexia nervosa (AN) is a serious disorder with associated morbidity and mortality, most commonly diagnosed in females. Existing literature on male anorexia is sparse, and a review of the endocrine effects of AN in males has not previously been published. Our objective is to highlight the clinical characteristics of AN in males as a routinely overlooked cause of multiple endocrinopathies and systemic illness in hospitalized patients.

METHODS

We present 4 cases (2 cases at The Mount Sinai Hospital; 2 cases at Long Island Jewish Hospital) of young men with hormonal dysfunction due to underlying AN. Pertinent de-identified data were collected from a chart review of cases seen on the endocrinology consult service at both hospitals. Institutional Review Board approval was not required for an observational report of the cases presented.

RESULTS

Four young men with AN demonstrated evidence of multiple systemic complications from severe caloric and protein malnutrition. Varying degrees of endocrinopathies were present, including hypogonadotropic hypogonadism, hypercortisolemia, and nonthyroidal illness syndrome, resulting in bradycardia, gastroparesis, hypothermia, acute systolic heart failure, and erectile dysfunction. Ages at diagnosis were 20, 24, 23, and 20 years, with mean age 21.75 years. Most of the clinical effects from these endocrinopathies resolved with improved caloric intake and nutrition, although symptoms of hypogonadism persisted.

CONCLUSION

This small case series highlights the importance of AN as a potential cause of multiple endocrinopathies in males. The heterogeneous presentations and varying degrees of clinical manifestations in our cohort emphasize the challenge in diagnosis. Increased awareness of AN in males is vital, as its prevalence is likely underestimated and appropriate diagnosis and treatment can ameliorate the metabolic dysfunction in a majority of cases. Further studies on males with eating disorders are needed to help guide diagnostic and therapeutic decisions.

Classification of eating disturbance in children and adolescents: proposed changes for the DSM-V

Childhood and adolescence are critical periods of neural development and physical growth. The malnutrition and related medical complications resulting from eating disorders such as anorexia nervosa (AN), bulimia nervosa (BN) and eating disorder not otherwise specified may have more severe and potentially more protracted consequences during youth than during other age periods. The consensus opinion of an international workgroup of experts on the diagnosis and treatment of child and adolescent eating disorders is that (a) lower and more developmentally sensitive thresholds of symptom severity (e.g. lower frequency of purging behaviours, significant deviations from growth curves as indicators of clinical severity) be used as diagnostic boundaries for children and adolescents, (b) behavioural indicators of psychological features of eating disorders be considered even in the absence of direct self-report of such symptoms and (c) multiple informants (e.g. parents) be used to ascertain symptom profiles. Collectively, these recommendations will permit earlier identification and intervention to prevent the exacerbation of eating disorder symptoms.