Practice Essentials
Bulimia nervosa is an eating disorder characterized by binge eating and purging. It usually begins in adolescence or young adulthood, and is far more common in females than in males.
Signs and symptoms
Symptoms of binge eating include the following:
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Lack of control over eating
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Secrecy surrounding eating
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Eating unusually large amounts of food
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Irregular eating habits
Symptoms of purging include the following:
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Regularly going to the bathroom after meals
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Using laxatives or diuretics
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Smelling of vomit
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Exercising excessively
Some physical signs and symptoms associated with bulimia include the following:
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Normal body weight or increased body weight, with frequent fluctuations
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Low body temperature
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Hypotension
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Dental erosion
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Callouses or scars on the knuckles or hands
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Menstrual irregularity or amenorrhea
See Clinical Presentation for more detail.
Diagnosis
Lab studies and physical findings
No specific diagnostic test for bulimia nervosa currently exists. However, several laboratory abnormalities may occur as a consequence of purging, including:
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Hypokalemia
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Hypochloremia
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Hyponatremia
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Metabolic alkalosis (due to vomiting)
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Metabolic acidosis (due to laxative and diuretic abuse)
Diagnostic criteria (DSM-5)
Bulimia nervosa is characterized by recurrent episodes of binge eating and inappropriate compensatory behaviors to avoid weight gain, such as self-induced vomiting, using laxatives or diuretics, fasting, or exercising excessively. A third essential feature of the disorder is self-evaluation that is unduly influenced by body shape and weight. [1]
To qualify for the diagnosis of bulimia, the binge eating and inappropriate compensatory behaviors must occur, on average, at least once per week for 3 months.
See Workup for more detail.
Management
Cognitive-behavioral therapy (CBT) is the treatment of choice for bulimia nervosa. [2] In CBT, behavioral approaches to avoiding undesirable eating habits are used, including diary keeping; behavioral analyses of the antecedents, behaviors, and consequences (so-called ABCs) associated with binge eating and purging episodes; and exposure to food paired with progressive response prevention regarding binge eating and purging. Distorted or maladaptive thoughts regarding weight and shape are identified, examined, and addressed, and other dysfunctional irrational beliefs are explored and confronted to allow better understanding, enhanced self-control, and improved body image.
Other therapies that may be helpful include the following:
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Interpersonal psychotherapy (IPT)
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Nutritional rehabilitation counseling
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Family therapy
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Group therapy
Inpatient care is indicated for patients who are suicidal, have abnormal ECG findings or electrolyte levels, are dehydrated, or who do not respond to outpatient therapy.
See Treatment and Medication for more detail.
Background
Bulimia nervosa is an eating disorder characterized by binge eating and purging. It usually begins in adolescence or young adulthood, and is far more common in females than in males.
Diagnostic criteria (DSM-5)
Criteria for the diagnosis of bulimia include preoccupation with eating and overeating large amounts of food in short periods, also described as binge eating. This behavior is then followed by inappropriate behavior to avoid weight gain, most notably, self-induced vomiting. Other methods of avoiding weight gain include laxative/diuretic abuse and excessive exercise. Bulimia nervosa is a disease with a highly focused patient population; it is predominantly found in women and is virtually nonexistent in nonindustrialized countries. [1, 3, 4, 5, 6, 7, 8, 9]
Pathophysiology
Bulimia nervosa is a disease that most likely emerges from a complex integration of many factors. These factors may be psychological, cultural, environmental, and societal. Many proposed associated factors are involved in the development of bulimia. These factors can include chemical imbalances in neurotransmitters, such as serotonin or pancreatic polypeptides (eg, pancreatic peptide YY [PYY]). Psychological and psychiatric problems are also thought to contribute to the development of bulimia. Another contributing factor is family problems. Participation in extracurricular activities that emphasize body shape and image has also been linked to the development of bulimia.
The binge and purge cycle characteristic of bulimia affects multiple organ systems. The GI system can be affected by the overeating associated with binge episodes. This overeating can stretch the stomach or delay gastric emptying. Purging can induce esophagitis or esophageal rupture due to vomiting. Pancreatitis can also occur. Electrolyte abnormalities can include hypokalemia and hypochloremia. Cardiovascular abnormalities can lead to arrhythmias, arrest, cardiac rupture, or pneumomediastinum. The pulmonary system can be damaged by aspiration of gastric contents upon vomiting. Renal function impairment is also possible. [4, 6, 10, 11, 12, 13]
Epidemiology
Frequency
United States
The lifetime prevalence of bulimia nervosa among women is 1%–3%, and a comparable percentage of women have less severe variants of the disorder. Lifetime prevalence among men is 0.1%. [3, 13]
Although no concrete data are available, bulimia is a disease that is highly culturally dependent. It is found solely in societies in which a high cultural value is placed on slimness and is virtually nonexistent in nonindustrialized countries.
Mortality/Morbidity
Death is a relatively uncommon outcome for bulimia. Approximately 0-3% of women with the disease eventually die from complications of the disease; however, these numbers may be underestimated owing to low ascertainment rates and short follow-up periods.
The leading cause of death among patients with eating disorders is suicide, which is more common in patients with bulimia nervosa than in those with anorexia nervosa (AN). Factors most strongly associated with suicide attempt or suicidal ideation in patients with eating disorders include concurrent drug use, alcohol use, and tobacco use. [14] Suicide risk should be carefully monitored in patients with eating disorders who also have these risk factors.
One third of patients who present for treatment of bulimia nervosa have past histories of anorexia nervosa.
Bulimia has many complications (see Complications). [3, 10, 14]
Race
Bulimia has traditionally been thought of as a disease that predominantly affects whites. The low incidence of eating disorders among nonwhites has been attributed to differences among ethnic groups in ideal body image. Studies have shown that black women are less likely to develop eating disorders and tend to express more satisfaction with their bodies than white women of similar weight; however, other studies suggest that the incidence of bulimia among minority groups is higher than previously thought. Studies suggest that patients from higher socioeconomic groups are more likely to seek treatment, making the incidence within these groups appear to be higher.
Some population studies suggest an equal incidence of bulimia in blacks and whites. Overall, strong circumstantial evidence suggests that cultural factors play large roles in eating disorder development. Most cases of bulimia nervosa originate in industrialized countries. In general, industrialized countries are places where food is plentiful and a preoccupation with thinness in women is present. [5, 11]
Sex
Bulimia primarily occurs in young women. Males comprise only 2-8% of all bulimia cases; however, this number is thought to be on the rise. [15]
Age
Bulimia is most common in adolescents and young adults. Median age of onset is 18 years. [4, 9]
