Chapter 24: Eating Disorders

LEARNING OBJECTIVES

1. Explain the pathophysiology of eating disorders.

2. Describe the diagnostic criteria of eating disorders including anorexia nervosa, bulimia nervosa, and binge eating disorder.

3. Review nonpharmacologic interventions for the management of eating disorders.

4. Compare and contrast pharmacotherapy for the treatment of eating disorders.

5. Formulate a clinical plan for nonpharmacologic and pharmacologic treatment of patients with eating disorders including monitoring and patient education.

INTRODUCTION

Good nutrition is vital for health and a fundamental component of growth and development among children and in disease management among children and adults. Unfortunately, many adolescents and adults develop disordered eating patterns that often result in excessive loss of weight, drastic weight fluctuations, or obesity. Failure to maintain healthy eating and exercise patterns can result in numerous health conditions. Being underweight can be associated with health complications such as hormone disorders, osteoporosis, electrolyte abnormalities, seizures, heart arrhythmias, and heart disease.¹ Being overweight or obese can lead to complications such as diabetes, cardiovascular disease, osteoarthritis, sleep apnea, gallbladder disease, gastroesophageal reflux disease, and various cancers.^2,3 Establishing healthy eating and exercise patterns are vital to effectively prevent morbidity and mortality associated with being underweight, overweight, or obese.

Disordered eating patterns are quite common. Health care providers should be prepared to evaluate a patient’s weight status and eating habits to screen for possible illness. Health care providers can also introduce and reinforce healthy nutrition and appropriate exercise patterns. Staying abreast of treatment guidelines and other updates regarding weight management and dietary nutrition can better prepare the health care providers to initiate a dialogue with the patient to address concerns or screen for possible issues.

The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) was updated in 2013 resulting in a chapter now renamed Feeding and Eating Disorders.⁴ Disorders outlined in the chapter include pica (the ingestion of nonfood and nonnutritious materials), rumination disorder (involving the regurgitation of food), avoidant/restrictive food intake disorder (an eating disturbance secondary to lack of interest in or avoidance of food based on sensory features), binge eating disorder (BED; a new inclusion in the 5th edition characterized by episodes of binge eating) and the historically classic diagnoses of anorexia nervosa (AN) and bulimia nervosa (BN). This chapter will focus on AN, BN, and BED.

The lifetime prevalence of AN is estimated to be 0.3% to 0.9%, and 90% of those affected are women. Lifetime prevalence of BN is 0.8% to 2.9%, and once more, women make up the majority of the patient population. BED prevalence estimates are in the range of 2% to 3.5%, with a lower ratio of women versus men affected compared to AN and BN, although women continue to have higher rates.⁵ Quality of life is negatively impacted by the presence of AN, BN, or BED, and it is associated with higher rates of hospitalizations, outpatient ...