Bulimia nervosa is an eating disorder characterized by:

• Recurrent episodes of binge eating characterized by rapid consumption of large amounts of food in discrete periods of time, usually <2 hours
• Compensatory behavior such as self-induced vomiting, laxative or diuretic use, strict dieting, or vigorous exercise to induce weight loss
• Minimum average of 2 binge-eating episodes per week for at least 3 months
• Feeling of lack of control over eating behavior during eating binges
• Frenzied quality, often occurring alone and secretively
• Associated feelings of guilt, anxiety, low self-esteem, and depression
• Persistent overconcern with body shape and weight
• Symptoms and psychopathology may overlap with anorexia nervosa and eating disorder not otherwise specified

Emphasize healthy self-esteem and body image during visits with preadolescents and adolescents.

• Onset in late adolescence to early adulthood (range: 13–28 years of age)
• Females account for 85–90% of cases.
• 83% of patients have lifetime history of an anxiety disorder, 63% have a lifetime history of depression.

Prevalence

• Affects 1–3% of young females in Western countries
• Affects 4–10% of adolescent and college-age females
• 10 times more common than anorexia nervosa

Genetics
Recent studies, including twins studies, suggest that bulimia nervosa and binge eating is familial.

• Personality traits of low self-esteem, self-regulatory difficulties, frustration intolerance, and impaired ability to recognize and express feelings directly have been described in patients with bulimia nervosa.
• There appears to be a small positive association between childhood sexual abuse and the development of an eating disorder, but the size and nature of this association is as yet unknown.
• May be 2 subtypes:
  • Multi-impulsive: Patient relies on bingeing and purging as a way of regulating intolerable states of tension, anger, and fragmentation.
  • Postdieting: Binge eating is precipitated by dietary restraint with compensatory behaviors maintained by reduction of guilty feelings associated with fears of weight gain.
• Neuroendocrine abnormalities may also play a role: Abnormalities in serotonergic and vagal function have been demonstrated in patients with bulimia nervosa.
• Cholecystokinin response to a meal is decreased in patients with bulimia nervosa, which also may indicate abnormal satiety signaling.
• May be abnormalities in other hormones or neurotransmitters, such as leptin, dopamine, and endorphins, but unclear if these are cause or effect

History

• Eating-disorder specific:
  • Eating habits
  • Rituals, behaviors
  • Body image
  • Actual and desired weights, minimum and maximum weights
  • Use of laxatives, diuretics, diet pills, emetics
  • Presence of binge or purge behavior
  • Menstrual history
  • History of exercise
• General:
  • Weakness or fatigue, or hyperactivity
  • Thirst, frequent urination
  • Headaches
  • Abdominal pain, fullness, or bloating; nausea
  • Constipation or diarrhea
• Psychiatric:
  • Mood disorder
  • Substance abuse
  • Anxiety
  • Personality disorders
  • Suicidal tendencies
  • Low self-esteem
  • Feelings of ineffectiveness
• Family:
  • Medical and psychiatric histories

Physical Exam

• Vital signs: Check for hypotension.
• Weight: May be normal, overweight, or underweight
• Edema of hands and feet: Evidence of low albumin or compensatory renal sodium and water retention
• Calluses on knuckles or hands: Russell sign secondary to inducing vomiting
• Erosion of dental enamel: Exposure to gastric juices secondary to frequent vomiting
• Muscle cramps or weakness: Hypokalemia
• Special questions:
  • How much do you want to weigh?
  • How do you control your weight?
  • How do you feel about yourself?
  • How often do you vomit, use diuretics or laxatives?

Eating disorder questionnaires: Questionnaire assessments appear to be equivalent to diagnostic interview in diagnosing bulimia nervosa.

Laboratory

• Perform a laboratory evaluation as part of the diagnostic workup. Laboratory evaluation is most useful for assessing complications; there is no diagnostic or confirmatory laboratory test for bulimia nervosa. Many patients have normal laboratory studies.
• CBC: Iron-deficiency anemia
• Electrolytes, including calcium, magnesium, and phosphate: Abnormalities may occur as a result of prolonged vomiting or use of laxatives.
• Blood urea nitrogen (BUN) and creatinine: Renal function usually normal, but BUN may be elevated secondary to dehydration or low secondary to protein loss
• Glucose: Patient may be hypoglycemic.
• Cholesterol, lipids: May be elevated in starvation states
• Amylase: Pancreatitis
• Total protein, albumin, prealbumin: Usually normal, but may be low as evidence of malnutrition
• Liver function tests: Transaminases may be mildly elevated (up to twice normal).
• ESR: Almost invariably normal; if elevated, consider occult organic process
• Total carbon dioxide: Metabolic alkalosis from vomiting or metabolic acidosis if using laxatives
• Urine toxicology screen (optional): May be positive, as this disorder often is associated with substance abuse

Imaging

• Electrocardiogram with rhythm strip: May reveal U waves associated with hypokalemia
• Consider upper GI series with small-bowel follow-through
• Consider dual-energy x-ray absorptiometry (DEXA) scan if prolonged amenorrhea, to evaluate bone density

• Psychogenic vomiting
• Drug abuse
• Gastrointestinal obstruction
• Hiatal hernia

Hospitalize in cases of:

• Hypovolemia
• Severe electrolyte disturbances
• Intractable vomiting
• Acute psychiatric emergencies (e.g., suicidal ideation, acute psychosis)
• Medical complication of malnutrition (e.g., aspiration pneumonia, cardiac failure, pancreatitis, Mallory-Weiss syndrome)
• Comorbid diagnosis that interferes with the treatment of the eating disorder (e.g., severe depression, obsessive-compulsive disorder, severe family dysfunction)
• Failure of outpatient therapy

• Outpatient psychotherapy
• Cognitive behavioral therapy (CBT):
  • More effective than interpersonal psychotherapy or behavioral therapy alone
  • Helps patients determine other ways to cope with the feelings that precipitate purging and to try to correct maladaptive beliefs about body image
  • May also be done in a self-help format, which may be effective as well
  • 1 study of CBT in adolescents showed considerable promise
• Individual psychotherapy
• Family treatment (to help with dysfunctional family dynamics)
• Group therapy
• During treatment, patients and their families may cause “splitting” of the hospital staff. To avoid this, always be supportive and maintain consistency in stating goals.

Activity
Physical activity was shown in 1 study to reduce the pursuit of thinness and to decrease bingeing/purging behavior.

• Antidepressants:
  • Decrease the binge–purge behavior
  • Improve attitudes about eating
  • Lessen preoccupation with food and weight
  • Fluoxetine (Prozac), sertraline (Zoloft), desipramine, citalopram and fluvoxamine (Luvox) have been used with good results in patients with bulimia nervosa.
  • Effect of antidepressant may diminish over time, and patient may relapse when drug is stopped.
  • Psychotherapy combined with antidepressant therapy appears to have the best outcome.
  • Response rate to alternative treatments after cognitive behavioral therapy and antidepressant 1st-line therapy is generally low.
  • Few studies either of medication or psychotherapy have included patients 18 years of age, so preferred therapy in these patients still uncertain.
• Stool softeners: Often of little use for constipation; consider nonstimulating osmotic laxatives if severe
• Ondansetron: Shown in 1 study to decrease vomiting frequency; may help normalize the physiologic mechanism controlling satiation

• Reduction in binge and purge episodes may take months or years.
• Behavioral and thought disorders associated with bulimia nervosa may be of long duration.

• Very low mortality: 0.3% (but may be underestimated secondary to poor follow-up in studies)
• Most patients have episodic course with trend toward improvement.
• No studies of long-term prognosis in adolescents
• Adult studies: 5–10-year follow-up:
  • 50% made full recovery.
  • 30% relapsed.
  • 20% still met full criteria for bulimia nervosa.
• Poor prognostic indicators:
  • Concomitant depression, personality disorder, or substance abuse
  • Frequent vomiting
  • History of substance abuse
• Good prognostic indicators:
  • High motivation for treatment
  • No concurrent disruptive psychopathology
  • Good self-esteem

• Pulmonary:
  • Aspiration pneumonia
  • Pneumomediastinum
• GI:
  • Pancreatitis
  • Parotid or salivary gland enlargement
  • Gastric and esophageal irritation and gastroesophageal reflux
  • Mallory-Weiss tears
  • Paralytic ileus (due to laxative abuse and hypokalemia)
  • Severe constipation (due to laxative abuse and subsequent dependence)
• Metabolic:
  • Hypokalemia (due to laxative abuse or vomiting)
  • Secondary cardiac dysrhythmias, myopathy, ileus
  • Electrolyte imbalances, including hypomagnesemia; acid–base disturbances
  • Fluid imbalances
  • Hyperamylasemia
  • Edema (secondary to hypoproteinemia or renal sodium and water retention secondary to hypovolemia and secondary hyperaldosteronism)
  • Bone loss (if amenorrhea; significantly more common in anorexia nervosa)
• Dental:
  • Enamel erosion
  • Caries and periodontal disease

Signs to watch for:

• Weight loss or major weight fluctuations
• Electrolyte abnormalities
• Muscle cramps
• Fatigue
• Depression or mood disturbance
• Willful behavior or acting out

• 307.51 Bulimia nervosa
• 783.6 Bulimia

• Q: How do I determine if a patient has anorexia with vomiting or bulimia?
  • A: The key feature of bulimia nervosa is the binge episode, which distinguishes it from anorexia nervosa. If there are not at least 2 binge eating episodes per week for at least 3 months, the diagnosis is not bulimia.
• Q: What laboratory abnormalities should I look for in my patients with bulimia?
  • A: Electrolyte abnormalities, particularly hypokalemia. Patients may develop a hypochloremic metabolic alkalosis. If electrolytes are significantly abnormal, the patient should be hospitalized until they have normalized.

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Nadja Peter, MD