Anorexia nervosa is a relatively rare disorder affecting less than 1% of young women and a much smaller percentage of young men. Its most striking behavioral manifestation is the willful restriction of caloric intake secondary to an irrational fear of becoming fat, frequently in concert with a grossly distorted view of one’s self as overweight, even in the presence of severe emaciation. Patients often exhibit a phobic response to food, particularly to fatty and other calorically dense items. They develop an obsessive preoccupation with food, eating, dieting, weight, and body shape, and frequently exhibit ritualistic behaviors involving choosing, preparing, and ingesting meals (e.g., cutting food into very small pieces or chewing each bite a specific number of times).
Early in the course of the illness, patients begin to restrict many food items, as is typical of most dieters. As the disorder progresses, though, the anorectic’s menu becomes grossly constricted and he/she demonstrates greater rigidity. Minor variations in meal content can produce tremendous anxiety. Unlike the average dieter, the anorectic continues his/her pursuit of thinness to the extreme and becomes dependent on the daily registration of weight loss. This fuels even more restrictive dieting. Extreme dieting is often complicated by other weight-reducing behaviors. Exercise is frequently compulsive, and hyperactivity in underweight patients is a curious but often-encountered concomitant. Weakness, muscle aches, sleep disturbances, and gastrointestinal complaints, including constipation and postprandial bloating, are common physical findings. Amenorrhea, reflecting endocrine dysfunction secondary to malnourishment, is generally present.
Some anorectics engage in bulimic behaviors, including binging and purging. This binge–purge subtype of anorexia nervosa contrasts with the purely restricting subtype described earlier. Often, purging behavior, such as self-induced vomiting or the misuse of laxatives and diuretics, is seen in the absence of binging. The coupling of purging with self-starvation compounds the medical consequences of the disorder. Furthermore, anorectics, particularly adolescents, generally minimize their symptoms and the negative consequences of their disorder and are thus rarely motivated for treatment. The characteristics of the illness, both medical and psychological, are intensified with weight loss, further frustrating attempts at engaging the patient in a meaningful therapeutic process. Family and friends become increasingly anxious, angry, and at times alienated, as their loved one regresses. Superficial compliance, as is sometimes seen, belies a profound resistance. Anorectic patients can be challenging to treat as they cling tenaciously to their beliefs and behaviors.
Psychosocial dysfunction is common in patients with anorexia. Although educational performance may not be affected in adolescent patients, social relations become increasingly constricted, and sexual interest is generally diminished or absent.
The pathognomonic features of anorexia nervosa, namely the intense fear of becoming fat coupled with the relentless pursuit of thinness, are generally absent in other medical and psychiatric conditions. The term anorexia, which itself refers to absence of appetite, is a misnomer in the case of the syndrome of anorexia nervosa. True anorexia, such as that encountered in many medical conditions or diseases, would be accompanied by other signs or symptoms of those illnesses (as in gastrointestinal disease or many cancers).
Lack of appetite or decreased intake, with or without subsequent weight loss, is encountered in a number of psychiatric disorders. These include depression, hysterical conversion, other psychosomatic disorders, schizophrenia, and certain delusional disorders, but each of these is associated with a cluster of other substantiating symptomatology. Some patients with obsessive-compulsive disorder (OCD) may exhibit what appears to be bizarre behavior around food, eating, or meal preparation, but, on further exploration, their behavior is in response to obsessional ideation, for example, the fear of contamination. Such patients, in contrast to those with anorexia nervosa, generally admit their discomfort with the need to perform such compelling and often excessive or senseless acts.
In summary, although comorbid psychopathology may be encountered in patients with anorexia nervosa, including symptoms of depression or OCD, the hallmark of anorexia nervosa (the morbid fear of becoming fat and the relentless pursuit of thinness) is absent in other psychiatric syndromes. In none of these syndromes does the goal of weight loss drive the behavior.
Medical Complications & Treatment
Treatment of anorexia nervosa is initially directed at correcting the acute medical complications and is followed by supportive nutritional rehabilitation. Most medical consequences resolve with nutritional rehabilitation and the discontinuation of purging behaviors. Exceptions include persistent osteopenic changes in those who have experienced extended periods of malnourishment and suppression of growth in severe cases of adolescent anorexia.
In many cases of anorexia associated with significant weight loss (15–20% or more of ideal body weight) a structured inpatient facility is necessary to maintain an adequate level of medical surveillance and sustain a steady rate of weight gain. On admission to an inpatient treatment facility, laboratory screening should include tests for electrolytes, liver function, amylase (elevated in patients who purge), thyroid function, a complete blood count with differential, and a urinalysis. Common laboratory findings include leukopenia with a relative lymphocytosis, metabolic alkalosis with associated hypokalemia, hypochloremia, elevated serum bicarbonate levels, and, occasionally, metabolic acidosis in patients who abuse large amounts of stimulant-type laxatives. An electrocardiogram should also be obtained, since emaciation and associated electrolyte disturbances can contribute to significant cardiac abnormalities, especially in those who purge. Hypokalemia can lead to arrhythmia and the risk of cardiac arrest.
Acute medical conditions generally requiring immediate attention include electrolyte disturbances and dehydration, both of which are readily reversible. In most cases, initiating oral intake of fluids and food reverses minor disturbances in electrolytes and establishes adequate hydration. More severe cases, for example, patients with significant hypokalemia, may require intravenous hydration and parenteral replacement of depleted electrolytes, with daily electrolyte checks until the patient’s condition stabilizes. Care should be taken to avoid overhydration and the consequences of excess fluid retention in vulnerable individuals. Importantly, treatment must ensure prevention of purging behaviors in patients with this history, as persistence of purging will alter electrolyte and fluid balance.
In patients who are significantly underweight, use of a liquid supplement, initially as replacement for solid food, helps ensure necessary caloric intake. When given in divided feedings throughout the day, it may decrease the patient’s sense of postprandial discomfort and early satiety, both frequent consequences of extended caloric restriction and semistarvation. Further, this approach to refeeding decreases the inevitable manipulations around food choices. Replacement of solid food with a liquid supplement may also lessen the patient’s phobic avoidance of food and the subsequent anxiety around meal choices.
Given the lack of motivation and strong resistance to treatment exhibited by the majority of patients with anorexia, it is helpful to initiate behavioral strategies as soon as any acute medical condition is stabilized. Initial behavioral interventions, tied to daily weight gain in increments of no less than 0.25 lb or 0.1 kg, include obtaining visits from family or friends, lessening physical restrictions, and increasing involvement in activities on and off the unit. It is important that all contingencies be tied to daily weight gain, which is measured each morning at the same time and in like manner, as this is a quantifiable observation not open to argument or discussion. A milieu supportive of such interventions helps to motivate the patient and exerts pressure toward positive change.
As the patient reaches a target weight range and establishes some degree of commitment to treatment, solid food can replace the liquid supplement. The ability of the patient to maintain weight through normalization of intake marks a transition to less structured treatment, such as a partial hospitalization program or outpatient follow-up.
Other treatments applicable to both inpatient and outpatient settings include individual psychotherapy and family intervention. The initial focus in family therapy should be on psychoeducation and obtaining the support of family members. The dynamics that may be contributing to the patient’s eating disorder should be identified and, when possible, resolved. Such treatment often requires extensive contact beyond any acute interventions.
Individual psychotherapy is of limited value in the early stages of treatment, as the anorectic individual is generally unmotivated and, due to cognitive disturbances secondary to self-starvation, not capable of meaningful therapeutic work. Supportive therapy during this acute stage is often helpful in allaying anxiety and encouraging adherence to treatment. The more focused cognitive behavioral and interpersonal therapies are generally more effective when the patient has begun to gain weight and is beyond acute medical risk. Cognitive behavioral therapy focuses on the particular disturbing or distorted thoughts that contribute to the patient’s maladaptive behavior and helps the patient establish more effective behavioral alternatives. It may also be effective in dealing with the central psychological features of anorexia nervosa, such as disturbance in body image. Interpersonal therapy may also be helpful. It focuses on interpersonal conflicts rather than specific eating disturbances. Following stabilization and resolution of the acute crisis, including achievement of weight restoration, patients often require longer-term psychotherapeutic interventions.
Pharmacological therapy can play an adjunctive role in the management of both primary eating symptoms and their comorbid psychiatric features, including anxiety and depression. Such treatments should focus on particular target symptoms or behaviors. No single medication is consistently effective in managing the primary psychiatric disturbances of anorexia nervosa. Antidepressants, especially the selective serotonin reuptake inhibitors (SSRIs), can alleviate depressive symptoms and, due to their ability to regulate obsessive-compulsive symptomatology, may help reduce the preoccupations and ritualistic behaviors encountered in most anorectics. Low doses of atypical antipsychotics may sometimes be employed in severely obsessional or agitated patients, but side effects, including movement disorders and metabolic aberrations, limit their utility. Anxiolytics, especially benzodiazepines, should generally not be given to anorectics, as they are prone to development of addiction.