Eating disorders are debilitating biopsychosocial illnesses associated with serious medical illness and a high risk of death.1
Primary care physicians are often the first to see young women who have these problems, diagnose them, and start their evaluation and treatment.2–4 Many patients require acute medical interventions as well as long-term care for chronic medical issues. Therefore, primary care physicians play essential front-line and long-term roles in the multidisciplinary treatment team.
DEFINITIONS OF EATING DISORDERS HAVE CHANGED
Several problems existed in the category of eating disorders in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-4) and in the DSM-4 Text Revision (DSM-4-TR). These problems have been addressed in the fifth edition (DSM-5), released in 2013.5
One problem in the earlier editions was that many patients referred for treatment of eating disorders—more than 50% in one study6—did not meet the criteria for anorexia nervosa or bulimia nervosa and thus had to be categorized as having “eating disorder not otherwise specified.” Further, the earlier editions did not recognize that young children and adolescent males can be affected.7
Eating disorders are now recognized as an equal-opportunity disease, with all ethnic and socioeconomic groups affected. Children can run into medical trouble with even a small amount of weight loss or falling off the growth curve. Moreover, children and adolescents do not “experience” their bodies in the same way adults do; they may lack the vocabulary for eating-disorder thoughts.
For these reasons, the definitions of eating disorders have changed in the DSM-5.5
Anorexia nervosa. Older editions of the DSM listed amenorrhea as a criterion. This has been eliminated in DSM-5, since amenorrhea does not necessarily predict medical risk or treatment outcome; also, it is not applicable to males or premenorrheal girls and postmenopausal women.8 In addition, the requirement of low weight is now defined in the context of “age, sex, developmental trajectory, and physical health,” rather than the old threshold of 85% of expected weight.9
What remains unchanged is that anorexia nervosa is still characterized by self-starvation in order to maintain an abnormally low body weight, along with an intense fear of being fat and a disturbed self-image.
Bulimia nervosa. In both the old and the new editions of the DSM, bulimia nervosa is characterized by episodes of binge eating followed by inappropriate compensatory behaviors to avoid weight gain, such as vomiting, laxative abuse, diuretic abuse, and overexercise. In DSM-5, bulimia nervosa no longer has subtypes and requires only one binge per week with compensatory behavior, for at least 3 months. This change was based on the finding that there is no clear difference in psychopathology or treatment outcome between patients with one and two binge-purge episodes a week.10
“Eating disorder not otherwise specified” was a wastebasket category, lumping all those who did not meet the criteria for anorexia nervosa or bulimia nervosa or who did not neatly fit into a specific category.10 In DSM-5, subcategories were designed to help distinguish different treatment needs and outcomes between various subtypes.
Binge-eating disorder, one of the new subcategories, is characterized by binge eating without inappropriate compensatory behaviors.9 Patients with binge-eating disorder are often obese, have greater functional impairment, and are more likely to develop components of metabolic syndrome than obese patients without eating disorders.11
Avoidant/restrictive food intake disorder is another new DSM-5 diagnosis, characterized by failure to meet nutritional needs for reasons other than weight control. Reasons include disinterest in eating, dislike of sensory characteristics of food, or avoidance of consequences of eating. This disorder replaces the category “feeding disorder of infancy or early childhood,” since the condition can also occur in adolescents and adults.12
Other new diagnoses are:
- Atypical anorexia nervosa (if the patient is not underweight)
- Purging disorder
- Subthreshold bulimia nervosa (if the patient has < 1 episode per week or has had them for < 3 months)
- Subthreshold binge eating disorder (< 1 time a week or < 3 months)
- Night eating syndrome
- Pica and rumination disorder.
Regardless of the diagnostic label, the medical evaluation and treatment of anyone with an eating disorder should be tailored to the specific behaviors of the eating disorder. Medical complications can be subdivided into those from starvation, from purging, and from refeeding.