Eating Disorders: Anorexia & Bulimia Nervosa

Eating disorders kill through the body, not just the mind. Anorexia starves it; bulimia wrecks electrolytes and the esophagus. Medical stabilization comes first, weight, vital signs, and electrolytes, before the psychological work can land. These are illnesses of irregular eating and extreme distress about body weight or shape, and the intake disturbance harms the whole body.

What are Eating Disorders?

Eating disorders involve repeated disturbance of eating or eating-related behavior that alters intake or absorption of food and significantly harms physical health or psychosocial functioning. They sit on a continuum: anorexia nervosa eats too little or starves, bulimia eats chaotically, and obesity eats too much.

• The history is old. Records from the Middle Ages describe willful dieting to self-starvation in female saints fasting for purity.
• In the late 1800s, doctors in England and France described young women using self-starvation to avoid obesity.
• Anorexia nervosa was established as a mental disorder in the 1960s.
• Bulimia nervosa was first described as a distinct syndrome in 1979.

Types of Eating Disorders

• Anorexia nervosa. A life-threatening disorder marked by refusal or inability to maintain a minimally normal body weight, intense fear of gaining weight, badly disturbed perception of body shape or size, and refusal to acknowledge the seriousness of the problem.
• Bulimia nervosa. Recurrent episodes (at least twice a week for 3 months) of binge eating followed by inappropriate compensatory behaviors to avoid weight gain, such as purging, fasting, or excessive exercise.
• Binge-eating disorder (BED). Recurrent binge eating without the recurrent compensatory behaviors of bulimia, not occurring exclusively during bulimia or anorexia nervosa.
• Pica. Persistent eating of non-nutritive substances such as hair, dirt, and paint chips for at least 1 month.
• Rumination disorder. Repeated, persistent regurgitation of food after eating, not due to a medical condition or another eating disorder.
• Avoidant/restrictive food intake disorder (ARFID). Persistent failure to meet nutritional or energy needs from lack of interest in eating, aversion to certain sensory characteristics of food (color, texture, smell, taste), or fear of choking.
• Other specified feeding or eating disorder (OSFED). Eating behaviors causing clinically significant distress and impairment that do not meet full criteria for the other disorders.

Causes

Cause is unknown; dieting is often the initial stimulus.

• Biologic. Anorexia nervosa runs in families; genetic vulnerability may also come from a particular personality type or general susceptibility to psychiatric disorders.
• Developmental. Anorexia nervosa usually begins in adolescence or young adulthood, possibly tied to developmental issues.
• Family. Girls raised amid family problems and abuse are at higher risk for both anorexia and bulimia; disordered eating is a common response to family discord.
• Sociocultural. Adolescents idealize underweight actresses and models, and peer pressure adds to the risk.

Statistics and Incidences

Obesity is a major United States health problem, while millions of women starve themselves or eat chaotically in ways that can kill.

• 30% to 35% of normal-weight people with bulimia have a history of anorexia nervosa and low body weight, and about 50% of people with anorexia nervosa show bulimic behavior.
• More than 90% of anorexia nervosa and bulimia cases occur in females.
• Prevalence of both disorders is estimated at 1% to 3% of the United States general population.

Clinical Manifestations

Anorexia nervosa:

• Fear of gaining weight even when severely underweight.
• Body image disturbance.
• Amenorrhea.
• Depressive symptoms: depressed mood, social withdrawal, irritability, insomnia.
• Preoccupation with thoughts of food.
• Feelings of ineffectiveness; inflexible thinking.
• Strong need to control the environment.
• Limited spontaneity and overly restrained emotional expression.
• Constipation and abdominal pain.
• Cold intolerance; lethargy; emaciation.
• Hypotension, hypothermia, bradycardia.
• Hypertrophy of salivary glands.
• Elevated BUN.
• Electrolyte imbalances.
• Leukopenia and mild anemia.
• Elevated liver function studies.

Bulimia nervosa:

• Recurrent binge eating.
• Compensatory behavior: self-induced vomiting, misuse of laxatives, diuretics, enemas, or other medications, or excessive exercise.
• Self-evaluation overly tied to body shape and weight.
• Usually within normal weight range, possibly underweight or overweight.
• Restriction of total calories between binges, choosing low-calorie foods and avoiding foods seen as fattening or likely to trigger a binge.
• Depressive and anxiety symptoms.
• Possible substance use involving alcohol and stimulants.
• Loss of dental enamel; chipped, ragged, or moth-eaten teeth.
• Increased dental caries.
• Menstrual irregularities.
• Dependence on laxatives.
• Esophageal tears.
• Fluid and electrolyte abnormalities.
• Metabolic alkalosis (from vomiting) or metabolic acidosis (from diarrhea).
• Mildly elevated serum amylase levels.

Assessment and Diagnostic Findings

• Physical and mental status evaluation. Weight, vital signs, and potential physical complications, plus psychological state: body image, mood disturbances, and cognitive distortions about eating and food.
• Complete blood count (CBC). Hemoglobin is typically normal, elevated in dehydration; WBC is typically low from increased margination; thrombocytopenia is also seen.
• Blood chemistries. Hyponatremia (excess water intake or inappropriate antidiuretic hormone secretion), hypokalemia (diuretic or laxative use), hypoglycemia (lack of glucose precursors, low glycogen stores, or impaired insulin clearance), elevated BUN in dehydration, hypokalemic hypochloremic metabolic alkalosis (vomiting), and acidosis (laxative abuse).
• Liver function tests. Minimally elevated, without the levels seen in active hepatitis; albumin and protein are usually normal because the restricted intake still tends to contain high-quality protein.

Medical Management

Focus on weight restoration, nutritional rehabilitation, rehydration, and correction of electrolyte imbalances.

• Nutritional rehabilitation and weight restoration. Balanced meals and snacks gradually raise caloric intake to a normal level for size, age, and activity.
• Family-based therapy. Anorexia nervosa may respond best to family-based treatment (the Maudsley method) for achieving and maintaining remission.
• Cognitive behavioral therapy (CBT). Evidence-based for bulimia nervosa: diary keeping, behavioral analysis of the antecedents, behaviors, and consequences of binge-purge episodes, and food exposure paired with progressive response prevention.
• Interpersonal psychotherapy (IPT). Addresses interpersonal issues that drive symptoms, including grief, role transitions, role conflicts or disputes, and interpersonal deficits.

Pharmacologic Management

Few agents have shown clinical success.

• Electrolyte supplements. Repletion is necessary in profound malnutrition, dehydration, and purging, given orally or parenterally depending on clinical state.
• Fat-soluble vitamins. Meet dietary requirements and support metabolic pathways, DNA, and protein synthesis.
• Antidepressants, SSRIs. Reported to reduce binge eating, vomiting, and depression and improve eating habits, though their effect on body dissatisfaction is unclear.

Nursing Management for Eating Disorders

Nursing Assessment

Anorexia and bulimia differ, but assessment overlaps.

• History. Anorexia nervosa clients are often described as perfectionists with above-average intelligence, achievement-oriented, dependable, and approval-seeking; bulimia clients often have a history of impulsive behavior (substance abuse, shoplifting) plus anxiety, depression, and personality disorders.
• General appearance and motor behavior. Anorexia clients appear slow, lethargic, and fatigued, possibly emaciated; bulimia clients are usually near expected body weight, sometimes underweight or overweight.
• Mood and affect. Labile moods that track eating or dieting behavior.
• Thought processes and content. Most time is spent thinking about dieting, food, and food-related behavior.
• Self-concept. Low self-esteem is prominent.

Nursing Diagnosis

• Imbalanced nutrition, less than body requirements, related to purging or excessive laxative use.
• Ineffective coping related to inability to meet basic needs.
• Disturbed body image related to being excessively underweight.

Nursing Care Planning and Goals

The client will establish adequate nutritional eating patterns, eliminate compensatory behaviors such as excessive exercise and use of laxatives and diuretics, demonstrate coping mechanisms not related to food, voice feelings of guilt, anger, anxiety, or an excessive need for control, and accept body image with stable body weight.

Nursing Interventions

• Establish eating patterns. When the client can eat, a diet of 1200 to 1500 calories per day is ordered, with gradual increases to amounts adequate for height, activity, and growth. Monitor meals and snacks, often sitting with the client at a separate table, and keep the client in view of staff for 1 to 2 hours after eating to prevent vomiting.
• Identify emotions and build coping. Have the client describe feelings such as anxiety or guilt, allowing adequate time to respond.
• Address body image. Help the client accept a more normal body image, which may mean agreeing to weigh more than preferred to stay healthy and out of the hospital. Identifying personal strengths unrelated to food broadens self-perception.

Evaluation

Goals are met when the client establishes adequate nutritional eating patterns, eliminates compensatory behaviors, demonstrates coping not related to food, voices feelings of guilt, anger, anxiety, or excessive need for control, and accepts body image with stable body weight.

Documentation Guidelines

Document individual findings (contributing factors, interactions, social exchanges, specific behaviors); cultural and religious beliefs and expectations; the plan of care; the teaching plan; responses to interventions and teaching; and progress toward outcomes.