History
Obtaining a thorough history is essential in any patient in whom bulimia is suggested. Patients with bulimia often deny and make attempts to minimize the problem; however, thorough and careful questioning may reveal clues that the patient has bulimia. Often, patients have a history of dieting attempts and may admit to feeling fat even when they appear thin.
Patients often state that their self-esteem is linked closely to their body weight or shape. The patient may have a history of using diet pills, laxatives, ipecac, or thyroid medication to lose weight. Patients may become vegetarians or eat only select low-calorie foods. Diabetic patients may withhold insulin.
Patients who admit to purging behavior often describe a history of uncontrolled eating binges at least once weekly (DSM-5). During these binges, large amounts of food are consumed in private. Some patients plan ahead for binges by secretly hoarding food. They can also drive from one fast food restaurant to another so that those at home are not aware of the behavior. There is a large component of shame and guilt that accompanies both binging and purging behavior. Patients may describe feeling a loss of control when the binge begins, then a period of frenzied and rapid eating. The binge is followed by inappropriate compensatory behavior, usually self-induced vomiting. Excessive laxative use may occur too. Diabetics have been known to misuse their insulin as a dangerous way to purge calories.
Physical
The diagnosis of bulimia is not conditional on physical findings. Physical findings may not be present in all patients. Patients may have some findings, all findings, or none at all. The sections that follow describe the physical findings that are associated with bulimia. [3, 4, 5, 7, 10, 16, 17]
General findings include the following:
-
Normal body weight, but may be increased or decreased
-
Often frequent fluctuations in weight
-
Loss of subcutaneous fat
Vital signs:
-
Temperature - Hypothermia
-
Blood pressure - Hypotension
Head, ears, eyes, nose, and throat:
-
Dental erosion - Decalcification of dental surfaces exposed to vomitus (Amalgams and fillings are relatively resistant to acid and often project above the surface of the teeth. It is important to note that the surfaces of the teeth most often exposed to vomitus are facing the posterior oropharynx; therefore, a mirror may be necessary to fully evaluate dentition.)
-
Palatal trauma
-
Painless enlargement of parotid glands
-
Esophageal tears
Cardiovascular findings may include bradycardia.
Patients may present with frequent complaints of diffuse pain upon palpation of the abdomen.
Extremities:
-
Metacarpal phalangeal bruises, calluses, scarring, abrasions (Russell sign)
-
Edema possible if patient abuses laxatives or diuretics
-
Proximal muscle weakness if patient abuses ipecac
-
Waddling gait if patient abuses ipecac
Rectal prolapse may be present.
Causes
Bulimia nervosa (BN) is a complex disease that most likely emerges from an integration of physiological, psychological, and environmental factors. Currently, no defined single cause of bulimia nervosa is recognized. Several factors are believed to play a strong role in the development of bulimia. [3, 5, 11, 16, 18, 19]
Chemical
A few hypotheses suggest specific chemical abnormalities in the body are associated with bulimia.
Serotonin is a neurotransmitter with broad functions within the body. Among these functions, serotonin is involved in the development of satiety. Increased levels of serotonin are associated with decreased food intake. Serotonin is believed to increase postprandial satiety rather than directly decrease appetite.
One hypothesis of the development of bulimia involves abnormalities in serotonergic function. Some patients with bulimia have been found to have low serotonin levels. Because serotonin is involved in the development of satiety, these disturbances may contribute to the persistence of binge eating.
A potential hypothesis is that an impaired serotonergic response may contribute to the blunted satiety and prolonged periods of rapid food ingestion present in bulimia nervosa. Dieting has also been associated with altered serotonin function, more markedly in women than in men. Dieting is often a precursor to the development of bulimia; however, not all women who diet develop bulimia. This hypothesis is not thought to provide a sufficient sole explanation for the development of bulimia.
Another suggested pathophysiology involves increased levels of peptides involved in mediating appetite. Increased levels of a pancreatic polypeptide PYY, a peptide known to increase appetite, have been found in some patients with bulimia after a period of eating stability. This would suggest that these patients have a higher level of appetite, even when given a normal diet.
Psychiatric
Premorbid psychiatric disorders are often associated with development of bulimia. These can include affective disorders, anxiety disorders, and substance abuse.
Many patients with bulimia have concomitant depression and/or bipolar disorder.
Psychological and environmental
The strongest risk factor in the development of bulimia is history of dieting. Many patients report that their eating binges began in the context of or immediately following a diet. Many patients continue to restrict their caloric intake even when not binge eating.
Strong circumstantial evidence suggests that cultural factors play a large role in eating disorder development. Most cases of bulimia nervosa originate in industrialized countries where food is plentiful and a preoccupation with thinness in women is present.
Obesity is another risk factor for bulimia.
Family
Family conflict and instability are also associated with the development of bulimia.
A history of sexual abuse has been associated in some literature as a risk factor for development of bulimia.
A family history of eating disorder increases a child's risk of developing an eating disorder to 2-20 times that of the general population.
Interests and activities
Certain athletes and groups are thought to be more prone to development of bulimia. Specifically, these include ballet dancers, models, cheerleaders, runners, gymnasts, weight lifters, body builders, jockeys, divers, wrestlers, figure skaters, and field hockey players. Persons in these particular sports and activities often place a high value upon thinness or maintaining a particular weight.
The bodies of participants in these activities are often on display in front of crowds or judged in terms of body shape and weight. These high-pressure situations and preoccupation with weight can place teens at risk for eating disorders.
