Associated descriptive features and mental disorders. Individuals with Bulimia Nervosa typically are within the normal weight range, although some may be slightly underweight or overweight. The disorder occurs but is uncommon among moderately and morbidly obese individuals. There are suggestions that, prior to the onset of the Eating Disorder, individuals with Bulimia Nervosa are more likely to be overweight than their peers. Between binges, individuals with Bulimia Nervosa typically restrict their total caloric consumption and preferentially select low-calorie (“diet”) foods while avoiding foods they perceive to be fattening or likely to trigger a binge.
There is an increased frequency of depressive symptoms (e.g., low self-esteem) or Mood Disorders (particularly Dysthymic Disorder and Major Depressive Disorder) in individuals with Bulimia Nervosa. In many or most individuals, the mood disturbance begins at the same time as or following the development of Bulimia Nervosa, and individuals often ascribe their mood disturbances to Bulimia Nervosa. However, in some individuals, the mood disturbance clearly precedes the development of Bulimia Nervosa. There may also be an increased frequency of anxiety symptoms (e.g., fear of social situations) or Anxiety Disorders. These mood and anxiety disturbances frequently remit following effective treatment of Bulimia Nervosa. The lifetime prevalence of Substance Abuse or Dependence, particularly involving alcohol or stimulants, is at least 30% among individuals with Bulimia Nervosa. Stimulant use often begins in an attempt to control appetite and weight. A substantial portion of individuals with Bulimia Nervosa also have personality features that meet criteria for one or more Personality Disorders (most frequently Borderline Personality Disorder).
Preliminary evidence suggests that individuals with Bulimia Nervosa, Purging Type, show more symptoms of depression and greater concern with shape and weight than individuals with Bulimia Nervosa, Nonpurging Type.
Associated laboratory findings. Frequent purging behavior of any kind can produce fluid and electrolyte abnormalities, most frequently hypokalemia, hyponatremia, and hypochloremia. The loss of stomach acid through vomiting may produce a metabolic alkalosis (elevated serum bicarbonate), and the frequent induction of diarrhea through laxative abuse can cause metabolic acidosis. Some individuals with Bulimia Nervosa exhibit mildly elevated levels of serum amylase, probably reflecting an increase in the salivary isoenzyme.
Associated physical examination findings and general medical conditions. Recurrent vomiting eventually leads to a significant and permanent loss of dental enamel, especially from lingual surfaces of the front teeth. These teeth may become chipped and appear ragged and “moth-eaten.” There may also be an increased frequency of dental cavities. In some individuals, the salivary glands, particularly the parotid glands, may become notably enlarged. Individuals who induce vomiting by manually stimulating the gag reflex may develop calluses or scars on the dorsal surface of the hand from repeated trauma from the teeth. Serious cardiac and skeletal myopathies have been reported among individuals who regularly use syrup of ipecac to induce vomiting.
Menstrual irregularity or amenorrhea sometimes occurs among females with Bulimia Nervosa; whether such disturbances are related to weight fluctuations, to nutritional deficiencies, or to emotional stress is uncertain. Individuals who chronically abuse laxatives may become dependent on their use to stimulate bowel movements. The fluid and electrolyte disturbances resulting from the purging behavior are sometimes sufficiently severe to constitute medically serious problems. Rare but potentially fatal complications include esophageal tears, gastric rupture, and cardiac arrhythmias. Rectal prolapse has also been reported among individuals with this disorder. Compared with individuals with Bulimia Nervosa, Nonpurging Type, those with the Purging Type are much more likely to have physical problems such as fluid and electrolyte disturbances.