Most studies show that anorexia nervosa has a range of mortality rates from 5 percent to 18 percent. Indicators of a favorable outcome are admission of hunger, lessening of denial and immaturity, and improved self-esteem. Such factors as childhood neuroticism, parental conflict, bulimia nervosa, vomiting, laxative abuse, and various behavioral manifestations (e.g., obsessive-compulsive, hysterical, depressive, psychosomatic, neurotic, and denial symptoms) have been related to poor outcome in some studies but not in others.

No laboratory tests can provide a diagnosis of anorexia nervosa. The medical phenomena present in this disorder result from the starvation or purging behaviors. However, several relevant laboratory tests should be obtained in these patients. A complete blood count often reveals leukopenia with a relative lymphocytosis in emaciated anorexia nervosa patients. If binge eating and purging are present, serum electrolytes will reveal hypokalemic alkalosis. Fasting serum glucose concentrations are often low (not increased) during the emaciated phase, and serum salivary amylase concentrations are often elevated (not decreased) if the patient is vomiting. An electrocardiogram may show ST-segment and T-wave changes, which are usually secondary to electrolyte disturbances; emaciated patients will have hypotension and bradycardia. Adolescents may have an elevated (not decreased) serum cholesterol level. All of these values revert to normal with nutritional rehabilitation and cessation of purging behaviors. Endocrine changes that occur, such as amenorrhea, mild hypothyroidism, and hypersecretion of corticotrophin-releasing hormone, are attributable to the underweight condition and revert to normal with weight gain.

Features associated with anorexia nervosa include onset between the ages of 10 and 30 years; lanugo (neonatal-like body hair), not normal hair structure and distribution; mortality rates of 5 to 18 percent (not 20 to 25 percent); and the fact that 4 to 6 percent (not 7 to 9 percent) of those affected are male.

The diagnostic challenges of eating disorders are only partly addressed when a specific eating disorder is identified because in the large majority of cases, comorbid psychiatric disorders accompany the eating disorder, with two to four separate additional diagnoses on Axis I or II of the text revision of the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) commonly seen. Anorexia nervosa is associated with depression in 65 percent of cases, social phobia in 34 percent of cases, and obsessive-compulsive disorder in 26 percent of cases. There is also a high comorbidity of anorexia nervosa with body dysmorphic disorder—estimated at 20 percent—in which patients additionally have obsessional preoccupations regarding specific body parts not related to weight or shape in particular.

In general, anorexia nervosa patients who are 20 percent below the expected weight for their height are recommended for inpatient hospital programs, and patients who are 30 percent below their expected weight require psychiatric hospitalization for 2 to 6 months. The decision to hospitalize a patient is based on the patient’s medical condition and the amount of structure needed to ensure patient cooperation. The first consideration in the treatment of anorexia nervosa is to restore patients’ nutritional state; dehydration, starvation, and electrolyte imbalances can seriously compromise health and, in some cases, lead to death.

Medications can be useful adjuncts in the treatment of anorexia nervosa. The first drug used in treating anorexic patients was chlorpromazine (Thorazine). This medication is particularly helpful for severely ill patients who are overwhelmed with constant thoughts of losing weight and behavioral rituals for losing weight. There are few double-blind controlled studies to definitively prove this drug’s effectiveness for calming such patients and inducing needed weight gain. Cyproheptadine (Periactin) in high dosages (up to 28 mg a day) can facilitate weight gain in anorectic restrictors and also has an antidepressant effect. Some recent studies indicate that fluoxetine (Prozac) may be effective in preventing relapse in patients with anorexia nervosa.

Amitriptyline (Elavil) has been reported to have some benefit in patients with anorexia nervosa, as have imipramine (Tofranil) and desipramine (Norpramin). There is some evidence that electroconvulsive therapy (ECT) is beneficial in certain cases of anorexia nervosa associated with major depressive disorder.

Most experienced eating disorder clinicians would diagnosis the patient above with anorexia nervosa, restrictor subtype, because she restricted her food intake and she pushed herself hard in her training, even harder than her teammates on the track team, because she feared she was becoming fat and her performance on the track team was in jeopardy. She does not meet the strict “letter of the law” for anorexia nervosa, but she does meet all of the core clinical psychopathological and behavioral criteria for anorexia nervosa. However, under strict DSM-IV-TR criteria, this patient would be diagnosed as having an eating disorder not otherwise specified because she did not reach less than 85 percent of “expected weight” and still retain some menstrual functioning.