What are the complications of bulimia nervosa?

The complications of bulimia nervosa are serious and can adversely affect teeth, the esophagus and entire gastrointestinal system, the reproductive cycle and hormones, and electrolyte balances, which in turn can affect the heart. Some complications can be life threatening. Also, patients with underlying depression or substance abuse disorder may be at risk of suicide. According to a recent review, about one-quarter to one-third of people with an eating disorder have considered suicide, and about one-quarter to one-third of people with bulimia nervosa have attempted suicide. The authors reported that people with bulimia nervosa are seven times more likely to die by suicide than their peers without an eating disorder (Smith et al. 2017).

Stomach acid can erode the enamel of teeth, exposing soft dentin and making the teeth more susceptible to cavities. This erosion may be prevented by using fluoride applications, taking mineral supplements, and rinsing with water or a baking soda solution after purging. Brushing the teeth after vomiting is harmful because it rubs off the weakened enamel. Dentists have many ways to repair eroded enamel, including fillings, composites, root canals, crowns, and dentures. However, most dentists advise against performing these restorative procedures until the patient is in recovery from bulimia nervosa.

Electrolyte imbalances are common in patients with more severe bulimic symptoms, occurring in up to 49% of patients. These imbalances occur when ionized salt concentrations (commonly sodium and potassium) are at abnormal levels in the body. Potentially fatal irregular heart rhythms can occur as a result, so testing patients for these imbalances is very important. Certain electrolyte imbalances—hypokalemia (potassium too low), metabolic alkalosis (blood too alkaline), and hypochloremia (chloride too low)—occur more often in patients who purge through vomiting or abuse diuretics.

Damage to the gastrointestinal system can start with erosion of the esophagus caused by vomiting. Over time, this damage can weaken and potentially rupture the esophagus, which is a life-threatening condition. Restricting food, purging by vomiting, or using laxatives can cause disrupted digestion, blockages in the intestines from undigested food, intestinal infections, and constipation, which can be a result of weakened intestine muscles or laxative dependence from overuse. Since the body absorbs many nutrients through the intestines, malnourishment from restriction or purging can result, which affects every system in the body, including the brain.

The menstrual cycles of females with bulimia nervosa can be altered, although few patients have long-term cessation of menses (amenorrhea), and many patients maintain their normal level of sexual activity. Some studies show that bulimic symptoms and behaviors improve during pregnancy in many women, but few recover totally. Also, bulimic pregnant women can experience complications during pregnancy directly associated with the bulimic behavior.

Female athletes with untreated bulimia nervosa often experience a syndrome that doctors refer to as the Female Athlete Triad. The Triad, originally defined in 1992, consisted of the presence of an eating disorder, amenorrhea, and osteoporosis. The definition was refined in 2007 because too many athletes were not being recognized if they did not possess all three components. Current definition of the Triad, which is now considered a “spectrum disorder” due to the range of dysfunction recognized in the three areas, consists of low energy availability, menstrual dysfunction or total absence, and low bone mineral density. Only one or two of these components needs to be present to warrant further testing and evaluation. According to a review, female athletes suffering from disordered eating were two to four times more likely to suffer a sports-related injury, particularly bone injuries (Matzkin et al., 2015).

Several medical tests may be ordered during the course of diagnosing, treating, and monitoring the patient with bulimia nervosa. Many of these tests are also used for other eating disorders. Which, if any, tests are used will depend on each patient’s medical status.

Medical tests to diagnose bulimia nervosa and monitor treatment

    • Complete blood count with differential
    • Urinalysis
    • Complete metabolic profile
    • Serum magnesium
    • Thyroid screen (T3, T4, TSH)
    • Electrocardiogram

Tests used if the patient is 15% to 20% or more below ideal body weight (usually applies to anorexia, but some patients with bulimia can also be underweight)

    • Chest x-ray
    • Complement 3
    • 24-hour creatinine clearance
    • Uric acid
    • Low weight lasting 6 months or longer, bone mineral density scan, and estradiol ID level in females or testosterone in males
    • Echocardiogram
    • Brain scan, if neurologic signs are present