History
Case study
A 21-year-old woman is brought into an outpatient clinic by her mother, who complains that her daughter has been demonstrating unusual eating patterns since she moved back home 6 months ago. Her mother observes her to eat large amounts of food, such as desserts, when she is alone, often finding food wrappers hidden in her daughter’s room. She is worried that her daughter may be engaging in vomiting after these episodes of heavy eating. She often isolates herself in the bathroom for 10-20 minutes after a large meal.
When the patient was asked about her eating habits, she admitted to a “loss of control.” She described feeling deep remorse when she eats more than she would like. Furthermore, she described feeling so laden with guilt about her eating binges that she purposefully induces vomiting at least once every other day. This act gives her tremendous relief. She admits that she is unhappy with her overall appearance, and feels that she is “fat” and “out of shape.” She is preoccupied with her appearance and says that she compares herself to other women “all day long.” She also admits to feeling sad most days. She endorses experiencing occasional missed menstrual periods, low libido, low energy, and intermittent sore throat.
Historically, the patient has memories of a chaotic childhood. She is an only child whose parents fought often and finally divorced when she was 9 years old. The patient remembers the first time she induced vomiting at 10 years old, after she felt “too full after a large meal.” The mother describes her daughter as having few friends and as tending to isolate herself. However, the mother describes her as very bright; in fact, she was valedictorian of her high school.
On physical examination, the patient’s blood pressure is 90/60, heart rate is 100, and BMI is 19. Her oropharynx appears injected without areas of erosion, and multiple dental caries are seen. Bilateral parotid enlargement with minor tenderness is present. The patient is tachycardic and bowel sounds are hyperactive. The abdomen is soft, nontender, and nondistended. Skin turgor is poor.
On mental status examination, the patient presents as a young Caucasian woman with average body habitus and pale skin. She is meticulously dressed and groomed. She answers questions curtly, makes poor eye contact, and demonstrates mild foot tapping throughout the interview. Her mood is anxious and her affect is mood congruent but restricted to negative emotionality. She is highly articulate. Thought process is linear and goal directed. Methodical about her statements, she often takes time to clarify what she “really means.”
Thought content displays themes of shame and self-reproach, [33] though it is unclear whether shame is a risk factor for the development of AN and BN or a consequence of these difficulties; while guilt may be present, its role is unclear. No active delusions or hallucinations are present. Her cognition is grossly intact. She denies suicidal thoughts, but sometimes wishes she was “invisible.” She has no violent or homicidal thoughts. Insight is limited regarding her ability to acknowledge her psychiatric illness. Her judgment is impaired considering her inability to recognize the potential negative health consequences of her eating behaviors.
Prior to entering your office, laboratory assessment obtained at the suggestion of her primary care doctor reveals a serum potassium level of 3.8 Meq/L and serum amylase level of 140 Units/L.
Take-home points
The differential diagnosis of BN includes depression, anxiety and age-appropriate developmental problems (eg, lack of esteem). These issues are common co-occurrences.
A biopsychosocial treatment plan will be necessary to provide her the care she needs.
Collaboration with primary care providers is often necessary for short-term and sometimes long-term.
History
BN is often not diagnosed for many months or even years after onset because of the patients' secretiveness about their difficulties, usually associated with a great deal of shame. These patients often see physicians for other problems, such as anxiety, depression, infertility, bowel irregularities, fatigue, or palpitations. Similarly, they may see mental health professionals for mood and anxiety problems, personality issues, relationship issues, histories of childhood or adolescent trauma, or substance abuse, without revealing the presence of an eating disorder.
One common presenting scenario is that of a patient who is concerned her about weight who seeks help with weight loss. Symptoms may include bloating, constipation, and menstrual irregularities. Far less often, people may present with palpitations resulting from arrhythmias, which are often associated with electrolyte abnormalities and dehydration. BN is also characterized by an inappropriate premium placed on slender physical appearance, though less prominently than in anorexia nervosa.
A dietary history may reveal attempts to control weight by dieting and abstaining entirely from high-calorie foods at all times except during binge-eating episodes. Often, a morbid preoccupation with food and eating is present, and recurring cycles of extreme dieting and/or fasting may alternate with gorging behavior. Usually, bingeing episodes are well planned. High-calorie foods that are easy to swallow and to vomit are usually chosen. Patients may rapidly ingest up to 10 times (or more) of the recommended daily calorie allowance in a single binge episode. Understandably, patients often try to avoid social situations in which they might too easily lose control over their food intake (eg, parties, eating out).
Patients with BN frequently engage in physical activity cyclically, in a fashion similar to that of the binging episodes. Most patients self-induce vomiting by gagging themselves with their fingers or a toothbrush. Some patients are able to regurgitate reflexively, without requiring external stimulation of the pharynx. [34] A minority of patients will chew, then regurgitate, without actually swallowing the food. One particularly dangerous form of vomiting is via induction through the use of emetics (eg, ipecac). Ipecac is a tightly binding and slowly released myotoxin that may lead to fatal cardiomyopathy in habitual users. Up to 40% of patients misuse laxatives, thinking that their use will help them lose weight. In fact, laxative misuse results in additional dehydration and often electrolyte abnormalities as well. Screening for laxative use should be a routine topic of assessment.
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Patients with BN may experience the following symptoms:
General - Dizziness, lightheadedness, palpitations (due to dehydration, orthostatic hypotension, possibly hypokalemia)
Gastrointestinal symptoms - Pharyngeal irritation, abdominal pain (more common among persons who self-induce vomiting), blood in vomitus (from esophageal irritation and more rarely actual tears, which may be fatal), difficulty swallowing, bloating, flatulence, constipation, and obstipation
Pulmonary symptoms - Uncommonly aspiration pneumonitis or, more rarely, pneumomediastinum
Amenorrhea - Occurs in up to 50% of women with BN; significant proportion of remaining patients have irregular periods. Many more will have menstrual irregularity and scanty periods.
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A high index of suspicion is required in any depressed or anxious weight-conscious young woman.
A set of screening questions, such as the SCOFF mnemonic questionnaire [35] , is useful to obtain a quick impression as to the potential need for further in-depth questioning. The SCOFF questionnaire includes the following 5 questions:
Do you make yourself S ick because you feel uncomfortably full?
Do you worry you have lost C ontrol over how much you eat?
Have you recently lost more than O ne stone (about 14 lbs or 6.35 kg) in a 3-month period?
Do you believe yourself to be F at when others say you are too thin?
Would you say that F ood dominates your life?
The Eating Disorder Screen for Primary Care (ESP) questionnaire is an alternative screening tool. [36] It contains the following 5 questions:
Are you satisfied with your eating patterns?
Do you ever eat in secret?
Does your weight affect the way you feel about yourself?
Have family members suffered from an eating disorder?
Do you currently suffer with or have you in the past suffered with an eating disorder?
The Eating Attitudes Test (EAT) is a self-report population-based screening instrument that patients can complete in the waiting room prior to seeing the health care provider. [37] (See Psych Central for more information.)
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Family history of eating disorders, anxiety, mood disorders, and alcohol and/or substance abuse/dependence may contribute to the risk of BN and should be investigated.
Generally, patients with BN are more likely than controls to view their families as conflicted, badly organized, noncohesive, and lacking in nurturance and caring. These patients have also been shown to more often appear to be angrily submissive to hostile and neglectful parents.
Perceptions of appearance-related teasing by family members may be present. [38]
For individuals still living with their parents, careful assessment of the family’s dynamics should be undertaken.
Physiological abnormalities
Many physiological abnormalities may be seen in association with eating disorders, but virtually all appear to be consequences of the abnormal behaviors, not their causes. In most cases of BN, laboratory abnormalities are relatively minor. In cases of very frequent purging (eg, daily or multiple times per day), abnormalities in electrolyte and serum amylase levels occur, but these and most other laboratory abnormalities are reversible with weight restoration and cessation of compensatory behaviors.
Among the identified metabolic consequences sometimes seen in BN are low plasma insulin, C peptide, triiodothyronine, and glucose values, as well as increased beta-hydroxybutyrate and free fatty acid levels. Both fasting and postbinge/postvomiting hypoglycemia are sometimes seen in some patients with BN. Some studies suggest increased secretory diurnal amplitudes in cortisol and adrenocorticotropic hormone (ACTH) in BN as well as blunted responses to corticotrophin-releasing hormone (CRH). However, these findings have been inconsistent among research studies.
Reports have also suggested abnormal responses to dexamethasone suppression similar to those seen in anorexia nervosa and major depressive disorder, more common among individuals with significant dietary restriction. Some authors have attributed these abnormalities to impaired dexamethasone absorption, which is demonstrated in some patients with BN. Similar to findings in anorexia nervosa, patients with BN tend to have higher growth hormone levels at night, while nocturnal prolactin levels tend to be less than those seen in controls.
Episodes of amenorrhea may occur in as many as 50% of women with BN. [39] About half of women with BN have anovulatory cycles while about 20% have luteal phase defects. Patients with anovulatory cycles generally have impaired luteinizing hormone pulsatile secretion patterns and associated reduced estradiol and progesterone pulse amplitudes. [39, 40]
Although the implications of many research findings are still unclear, and none of the following offer clinical tests of any merit, reports suggest involvement of the serotonin transporter [41, 42] , autoantibodies against neuropeptides [43] , various chromosome regions [44] , brain-derived neurotrophic factor [45] , and peptides leptin and ghrelin. [46] In a few instances, cerebral hemispheric lesions may be involved in pathogenesis. [47] Regional cerebral blood flow abnormalities have been noted in adolescents. [48] Endogenous opioids and beta-endorphins have been implicated in the maintenance of binge eating.
Comorbidity
A national comorbidity study examined lifetime comorbidities of other psychiatric diagnoses in conjunction with BN. [10] In general, the lifetime comorbidity of any psychiatric disorder is 94.5%
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Affective disorders: The common co-occurrence of eating disorders with affective disorders suggests a possible relationship between them. [49] Major depressive disorder (MDD) is particularly common (approximately 50%) in this regard. Whether the association is causative (primary), secondary to the BN itself, or represents a common set of risk factors for BN and MDD is still unclear. Depressive symptoms can occur during pregnancy and postpartum in women with BN. [50] Bipolar II disorder also appears to be more common in patients with BN than in patients without eating disorders. The lifetime comorbidity for bipolar I or II is 17.7%.
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Anxiety disorders: Obsessive-compulsive disorder (OCD) is more common in persons with BN (17.4% lifetime comorbidity) than in controls. Panic disorder, social phobia, specific phobias, generalized anxiety disorder (GAD), and posttraumatic stress disorder (PTSD) significantly contribute to comorbidity. Lifetime comorbidities have been reported at approximately 17.4% for OCD, 16.2% for panic disorder, 41.3% for social phobia, 50.1% for specific phobias, 11.8% for GAD, and 45.4% for PTSD.
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One study suggests that baseline clinical predictors such as female gender and family history of eating disorders might be specific to the later development of eating disorders in the context of childhood OCD. [51]
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Substance use disorders: Some evidence suggests a relationship between disorders of substance abuse and dependence and BN, including alcohol dependence [52] , nicotine dependence [53] , and drug dependence [54] . For example, with regard to smoking in healthy controls, there were significantly more smokers among people with bulimia (lifetime OR = 2.165) and BED (lifetime OR = 1.792), but not for those with anorexia (lifetime OR = 0.927). Studies on caffeine intake are mixed. [55] Alcohol abuse or dependence has a lifetime comorbidity with BN of 33.7%, whereas illicit drug abuse or dependence has a lifetime comorbidity of 26%.
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Impulse control disorders: In a study of lifetime prevalence of impulse control disorders in patients with BN, compulsive buying and intermittent explosive disorder were the most frequently reported disorders, at 17.6% and 13.2%, respectively. Higher than expected rates of kleptomania, pathological gambling, and trichotillomania have also been reported in patients with BN. [56]
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Attention deficit hyperactivity disorder (ADHD): ADHD may be associated with bulimia. [57] In one study of more than 2,000 female inpatients treated for BN, 9% were also diagnosed with ADHD. The average rate of ADHD in the general population of young women is approximately 3.4%. [58] Lifetime comorbidity with ADHD and BN has been reported to be as high as 34.9%.
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Other psychopathology: The role of sexual abuse in the development of eating disorders is controversial. [59] Some reports suggest a strong association, while others detect no increased association. Borderline personality disorder is found frequently. [60] These patients usually have histories of trauma and abuse and may represent a distinct subgroup. Pathologic narcissism [61] and identity impairment [62] may be present. Features of obsessive compulsive personality disorder (OCPD), particularly perfectionism, may be increased among patients with BN.
Suicidal behavior
BN is associated with increased risk of suicide attempts and suicidal ideations. [63] In one study, all-cause mortality rate for BN was 3.9%, higher than other reported studies in the past. [64] However, the standardized mortality ratio with respect to suicide was 6.51, a much higher than expected rate.
Physical
Although patients with bulimiia nervosa (BN) are often unremarkable in general appearance and frequently have no signs of illness on physical examination, several characteristic findings may occur.
Physical findings may include the following:
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Bilateral parotid enlargement, largely consequent to noninflammatory stimulation of the salivary glands, may be seen. [65] See parotid gland swelling in following image.
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In patients with significant self-induced vomiting, erosions of the lingual surface of the teeth, loss of enamel, periodontal disease, and extensive dental caries may be observed, as in the following image. [66]
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Russell sign (one of the few physical examination findings in psychiatry) manifests as callosities, scarring, and abrasions on the knuckles secondary to repeated self-induced vomiting. [67]
Other cutaneous manifestations can include telogen effluvium (sudden, diffuse hair loss), acne, xerosis (dry skin), nail dystrophy (degeneration), and scarring resulting from cutting, burning, and other self-induced trauma. [68]
Other nonspecific but suggestive findings that may reflect the severity of the disease include bradycardia or tachycardia, hypothermia, and hypotension (often associated with dehydration). Edema, particularly of the feet (and less commonly the hands), is found more often among patients with a history of diuretic abuse, laxative abuse, or both or in patients with significant protein malnourishment causing hypoalbuminemia.
Some patients may be clinically obese, but morbid obesity is rare. Patients with BN who are overweight may have excessive fat folds that favor humidity and maceration with bacterial and fungal overgrowth, striae due to skin overextension, stasis pigmentation related to peripheral vascular disease, and plantar hyperkeratosis due to increased weight. [68]
A community-based household survey involving 52,095 adults in 19 countries found, after adjustment for pertinent comorbidities, that the rate of BN among the 2580 identified cases of adult-onset diabetes mellitus was twice that of non-diabetic individuals. [69]
A typical Mental Status Examination for a patient with BN is detailed below. (The formal Folstein Mini-Mental Status Examination [MMSE] is usually unnecessary in the evaluation of patients with BN because symptoms of dementia and delirium are not common in these patients.)
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Appearance: Patients are typically neat, well dressed, and show attention to detail. Grooming is often meticulous and may further demonstrate a patient's concern about personal appearance.
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Behavior: Patients usually do not have kinetic abnormalities, but anxious feelings may heighten psychomotor agitation. Movements are spontaneous, and patients generally are cooperative and able to carry out requested tasks.
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Cooperation: Patients generally avoid eye contact due to shame and embarrassment.
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Mood and affect: Patients often demonstrate a depressed mood but may also have significant anxiety.
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Speech: Content and articulation are generally normal.
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Thought process: Patients likely have a linear thought process that is goal-directed.
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Thought content: Thoughts tend to revolve around food and concerns regarding body image and weight.
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Perceptual disturbances: Delusions and hallucinations are typically absent.
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Suicidal ideation: Suicidal ideation is a significant consideration, especially in patients with depressed moods. Although suicidal ideation is often restricted to thoughts rather than concrete plans, suicidal thinking should be taken very seriously.
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Homicidal ideations: Homicidal ideation is not typically associated with those diagnosed with BN.
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Cognition: Patients are generally alert, and oriented to their surroundings. Attention and concentration typically measured by serial sevens and digit span are generally normal. Immediate memory is normal, as is recent and remote memory recall. Intellect is usually judged as normal, and in some cases, intellect ability may surpass average. Capacity to read and write is within normal limits. Visuospatial functions are also intact.
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Judgment: Patients generally demonstrate poor judgment regarding self care and treatment. Weight-reducing strategies such as induced vomiting, laxative, and diuretic ingestion are often perceived as legitimate and appropriate methods of weight management.
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Insight: Insight regarding the presence and significance of disturbances is variable. While patients typically admit to episodes of binge eating, they often do not appreciate their inappropriate fixation on eating or their distorted ideas of body image and weight.
Causes
Biological factors
Neurotransmitters [70, 71, 72]
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Serotonin: Serotonin is possibly closely related to weight regulation and eating behaviors. There have been documented cases of elevated serotonin in the cerebral spinal fluid in patients with anorexia nervosa (AN) and bulimia nervosa (BN).
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Norepinephrine: Lower levels of serum neurotransmitter are typically thought to be associated with AN.
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Dopamine: Dopamine activity is thought to be associated with distortion of body image, and a 7 repeat allele of the D4 receptor gene is thought to be associated with both BN and binge eating. This 7 repeat allele is thought to possibly be involved with weight gain in patients with BN.
Hormonal
Although many reported abnormalities in BN may reflect consequences of binge eating and purging rather than causal factors, complex irregular interactions exists between orexigenic factors such as neuropeptide Y (NP-Y), peptide Y (PYY), and anorectic factors such as cholecystokinin (CCK) and beta-endorphin. Patients with active BN have normal NP-Y and PYY levels, which do increase after successful treatment. Patients with AN, on the other hand, have elevated levels of NP-Y and lower levels of PYY (therefore, less orexigenic peptide action). Furthermore, people with BN have reduced beta-endorphin, normal dynorphin, and low CCK levels.
Genetics
Although no definitive inheritance patterns have been identified, a familial component appears to be involved in the development of eating disorders. Patterns of transmission involving monozygotic and dizygotic twins suggest genetic contributions in both anorexia nervosa and NB. There have been proposed genetic links at chromosomes 1, 3, and 10p related to BN. Genome-wide association studies are currently ongoing to further explore this association. Unfortunately, studies to date have been small with poor power. Chromosome 10p may also be linked with obesity in addition to BN.
Suppression of cholecystokinin and ghrelin after meals may be decreased in individuals suffering from BN. This may suggest a predisposing factor that could lead to impaired sense of satiety and influence eating disorder behavior. [73]
Developmental factors
Developmental factors include childhood anxiety, (eg, difficulties separating from caretakers). [74] History of childhood trauma and neglect, including subtle degrees of psychological abuse, teasing, and other interactions that generate self-doubt may increase vulnerability.
Psychological factors
Among psychological factors suggested are difficulties with self-esteem, affective self-regulation, impulsivity, perfectionism, body image distortion, susceptibility to triggers of a binge-purge cycle (which may occur around dieting and weight loss), and poor coping skills.
Sociocultural factors
Among the potential precipitating events for a binge/purge cycle in those with BN are anxiety states, emotional tension, boredom, environmental cues about food and eating, alcohol use, substance abuse, and exhaustion. For patients who severely restrict their usual food intake, hunger may precipitate an eating binge (in an “all-or-none” fashion). Excessive concerns about physical appearance, body image, and thinness seem central to both AN and BN.
Complications
Psychiatric complications
Studies suggest that patients with bulimia nervosa (BN) have increased rates of major depressive disorder, substance abuse, anxiety disorders, bipolar II disorder, and sexual abuse; these conditions should be considered and managed as necessary. Mortality and morbidity associated with depression (suicidal thoughts or self-injury) and poor impulse control (eg, substance abuse, sexually transmitted diseases, unintended pregnancy, accidental injuries) should always be anticipated and assessed. Patients with BN who are depressed and who have concurrent alcohol dependence are at exceptionally high risk of suicide, particularly those who overexercise. Studies have shows that in people with eating disorders, excessive exercise appears to be linked to an increased prevalence of acquired capability for suicide (ACS) and suicide attempts. [75, 76]
Medical complications
The all-cause mortality rate for BN per se is slightly lower than for anorexia nervosa (AN) (3.9% vs 4.0%, respectively). [64] Medical complications do arise and should be assessed carefully.
While the results of formal gastric emptying studies in patients with BN have yielded variable results (some suggesting delayed emptying time and others suggesting normal emptying time), acute gastric dilatation is a rare but concerning risk. This complication may result in gastric rupture, which may be fatal.
Among other rare potential complications are Mallory-Weiss tears of the esophagus, esophageal rupture, reflux esophagitis, and cardiomyopathies secondary to ipecac use.
Ipecac toxicity may be associated with skeletal myopathy, while chronic hypokalemia may also be associated with intestinal ileus, abdominal distension, exertional rhabdomyolysis, or both.
Hypokalemia-related distal renal tubulopathy is very rarely associated with BN.
Xerosis (dry skin) is a common finding in bulimia nervosa, which appears to be related to the chronic dehydration to which persons with BN are often prone.
Skin health usually requires an overall healthy nutritional status. Dermatological treatment is ordinarily topical.
Patients who chronically overuse and abuse laxatives risk chronic constipation, cathartic colon with pseudo-Hirschsprung syndrome, melanosis coli with increased risk for colon cancer, steatorrhea, and/or protein-losing enteropathy and metabolic consequences of hypophosphatemia and hypomagnesemia.
Other potential complications include osteopenia or osteoporosis, menstrual irregularity and infertility, and, less commonly, cognitive changes associated with dehydration and electrolyte and metabolic abnormalities.
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Parotid hypertrophy. Reprinted with permission from Mandel, L and Siamak, A. Diagnosing bulimia nervosa with parotid gland swelling. J Am Dent Assoc 2004, Vol 135, No 5, 613-616.
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Dental caries. Reprinted with permission from Wolcott, RB, Yager, J, Gordon, G. Dental sequelae to the binge-purge syndrome (bulimia): report of cases. JADA. 1984; 109:723-725.
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Russell sign. Reprinted with permission from Glorio R, et al. Prevalence of cutaneous manifestations in 200 patients with eating disorders. Int J Derm, 2000, 39(5), 348-353.
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This chest radiograph demonstrates pneumomediastinum, which can occur in association with esophageal rupture from forceful vomiting.
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Water-soluble contrast esophagram from a patient with esophageal perforation after esophageal dilation shows contrast leak (arrowheads) and normal esophageal lumen (arrows).
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Mallory-Weiss tear. Typical longitudinal mucosal tear with overlying fibrinous exudate extending from the distal esophagus to the gastric cardia. Courtesy of C.J. Gostout, MD.