The key feature of anorexia nervosa is self-imposed starvation resulting from a distorted body image and an intense and irrational fear of gaining weight, even when obviously emaciated. An anorexic patient is preoccupied with her body size, describes herself as “fat,” and commonly expresses dissatisfaction with a particular aspect of her physical appearance. Although the term anorexia suggests that the patient's weight loss is associated with a loss of appetite, this is rare.
Anorexia nervosa and bulimia nervosa can occur simultaneously. In anorexia nervosa, the refusal to eat may be accompanied by compulsive exercising, self-induced vomiting, or abuse of laxatives or diuretics.
Anorexia occurs in 5% to 10% of the population; more than 90% of those affected are females. It occurs primarily in adolescents and young adults but also may affect older women and, occasionally, males.
The prognosis varies but improves if the patient is diagnosed early or if she wants to overcome the disorder and seeks help voluntarily. Mortality ranges from 5% to 15%; the highest mortality is associated with a psychiatric disturbance. One-third of these deaths can be attributed to suicide.
Individual. Anorexia nervosa has often been seen as an escape from the emotional problems of adolescence and a regression into childhood. Patients will often have had dietary problems in early life. Perfectionism and low self-esteem are common antecedents. Studies suggest that survivors of childhood sexual or other abuse are at greater risk of developing an eating disorder, usually anorexia nervosa, in adolescence.
Family. Families of such patients are allegedly characterized by overprotection, inflexibility and lack of conflict resolution. Anorexia is alleged to prevent dissension in families. However, a case control study suggested that there is no more evidence of these factors in families of patients with anorexia nervosa than in control families with a child with an established physical disease, suggesting that, if present, these features are secondary.
Serious medical complications can result from the malnutrition, dehydration, and electrolyte imbalances caused by prolonged starvation, vomiting, or laxative abuse. For example, malnutrition may cause hypoalbuminemia and subsequent edema or hypokalemia, leading to ventricular arrhythmias and renal failure. Poor nutrition and dehydration, coupled with laxative abuse, produce changes in the bowel similar to those in chronic inflammatory bowel disease. Frequent vomiting can cause esophageal erosion, ulcers, tears, and bleeding as well as tooth and gum erosion and dental caries.
Cardiovascular complications can be life-threatening and include decreased left ventricular muscle mass, chamber size, and myocardial oxygen uptake; reduced cardiac output; hypotension; bradycardia; electrocardiographic changes, such as nonspecific ST interval, T-wave changes, and prolonged PR interval; heart failure; and sudden death, possibly caused by ventricular arrhythmias. Anorexia nervosa also may increase susceptibility to infection.
Amenorrhea may occur when the patient loses about 25% of her normal body weight. It usually is associated with anemia. Possible complications of prolonged amenorrhea include estrogen deficiency (increasing the risk of calcium deficiency and osteoporosis) and infertility. Normal menses usually return when the patient weighs at least 95% of her normal weight.
The patient's history usually reveals a 15% or greater weight loss for no organic reason, coupled with a morbid dread of being fat and a compulsion to be thin. The anorexic patient tends to be angry and ritualistic. She may report amenorrhea, infertility, loss of libido, fatigue, sleep alterations, intolerance to cold, and constipation.
ASSESSMENT TIP The anorexic patient may wear oversized clothing in an attempt to disguise body size. She may layer clothes or wear unseasonably warm clothing to compensate for cold intolerance and loss of adipose tissue.
Hypotension and bradycardia may be present. Inspection may reveal an emaciated appearance, with skeletal muscle atrophy, loss of fatty tissue, atrophy of breast tissue, blotchy or sallow skin, lanugo on the face and body, and dryness or loss of scalp hair. Calluses of the knuckles and abrasions and scars on the dorsum of the hand may result from tooth injury during self-induced vomiting. Other signs of vomiting include dental caries and oral or pharyngeal abrasions.
Palpation may disclose painless salivary gland enlargement and bowel distention. Slowed reflexes may occur on percussion. Oddly, the patient usually demonstrates restless activity and vigor (despite undernourishment) and may exercise avidly without apparent fatigue.
During psychosocial assessment, the anorexic patient may express a morbid fear of gaining weight and an obsession with her physical appearance. Paradoxically, she also may be obsessed with food, preparing elaborate meals for others. Social regression, including poor sexual adjustment and fear of failure, is common. Like bulimia nervosa, anorexia nervosa often is associated with depression. The patient may report feelings of despair, hopelessness, and worthlessness as well as suicidal thoughts.
A diagnosis of anorexia nervosa is confirmed when the patient meets the following criteria documented in the DSM-IV:
* refusal to maintain body weight over a minimal normal weight for age and height (for instance, weight loss leading to maintenance of body weight 15% below that expected) or failure to achieve expected weight gain during a period of growth, leading to body weight 15% below that expected
* intense fear of gaining weight or becoming fat, even though underweight
* disturbance in perception of body weight, size, or shape (that is, the person claims to feel fat even when emaciated or believes that one body area is too fat even when obviously underweight)
* in females, absence of at least three consecutive menstrual cycles when otherwise expected to occur.
In addition, laboratory tests reveal clinical status and help to rule out endocrine, metabolic, and central nervous system abnormalities; cancer; malabsorption syndrome; and other disorders that cause physical wasting.
Abnormal findings that may accompany a weight loss greater than 30% of normal body weight include:
* low hemoglobin level, platelet count, and white blood cell count
* prolonged bleeding time due to thrombocytopenia
* decreased erythrocyte sedimentation rate
* decreased levels of serum creatinine, blood urea nitrogen, uric acid, cholesterol, total protein, albumin, sodium, potassium, chloride, calcium, and fasting blood glucose (resulting from malnutrition)
* levels of alanine aminotransferase and aspartate aminotransferase in severe starvation states
* elevated serum amylase levels when pancreatitis isn't present
* in females, decreased levels of serum luteinizing hormone and follicle-stimulating hormone
* decreased triiodothyronine levels, resulting from a lower basal metabolic rate
* dilute urine caused by an impairment in the kidneys' ability to concentrate urine
* nonspecific ST interval, T-wave changes, and prolonged PR interval on the electrocardiogram. Ventricular arrhythmias also may be present.
Appropriate treatment aims to promote weight gain or control the patient's compulsive binge eating and purging and to correct malnutrition and the underlying psychological dysfunction. Hospitalization in a medical or psychiatric unit may be required to improve the patient's precarious physical state. Hospitalization may be as brief as 2 weeks or may stretch from a few months to 2 years or longer.
A team approach to care-combining aggressive medical management, nutritional counseling, and individual, group, or family psychotherapy or behavior modification therapy-is the best approach. Treatment is difficult, and results may be discouraging. Many clinical centers are now developing inpatient and outpatient programs specifically for managing eating disorders.
Treatment may include behavior modification (privileges depend on weight gain); curtailed activity for physical reasons (such as arrhythmias); vitamin and mineral supplements; a reasonable diet, with or without liquid supplements; subclavian, peripheral, or enteral hyperalimentation (enteral and peripheral routes carry less risk of infection); and group, family, or individual psychotherapy.
All forms of psychotherapy, from psychoanalysis to hypnotherapy, have been used in treating anorexia nervosa, with varying success. To be successful, psychotherapy should address the underlying problems of low self-esteem, guilt, and anxiety; feelings of hopelessness and helplessness; and depression.