Treating bulimia nervosa
Bulimia nervosa—or just "bulimia," as it's often called— is characterized by a cycle of binge eating followed by one of a variety of compensatory actions to avoid weight gain. Researchers estimate that one to three women out of 100 will develop bulimia nervosa at some point in their lives. In men, the rate of diagnosis is only about one-tenth the rate in women.
The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) describes two types of bulimia, based on the strategy a patient uses to rid herself of excess calories. People diagnosed with the purging type, the most common form, may self-induce vomiting or use laxatives or diuretics. In the nonpurging type, people may exercise excessively or stop eating for a day or longer.
Diagnosis is sometimes difficult because people suffering from bulimia tend to be ashamed of their eating behavior and engage in both bingeing and compensatory behavior in private. Because they rid themselves of the excess calories consumed while bingeing, most patients maintain a normal weight.
But the punishing compensatory strategies — especially repeated vomiting or laxative use — strain the body. In the long term, those with bulimia risk developing a number of serious medical complications, including irregular menstrual periods or amenorrhea (absence of menstruation), dehydration from reduced fluid intake, damage to teeth and gums from vomiting, electrolyte imbalances that can induce heart arrhythmias, and a variety of gastrointestinal disorders.
Biology, psychology, society
Family and twin studies indicate that bulimia nervosa is about 55% heritable—there is a genetic component. However, environmental triggers—such as growing up in a culture that values being thin—also can have a strong influence.
As with anorexia nervosa, girls most vulnerable to developing bulimia tend to be perfectionists, yet have poor self-esteem and self-image (especially about their weight or the shape of their bodies). They may have trouble dealing with moods or controlling behaviors. Patients who have been sexually or physically abused in the past, or whose family members have lots of internal conflicts, are also more at risk for bulimia, as they are for other eating disorders.
Bulimia most often develops in late adolescence or young adulthood, with 18 being the most common age of onset. A binge eating episode is often triggered by stress, a depressed mood, intense hunger (following calorie deprivation), or abject feelings about weight or body shape.
Treatment options can take many forms and involve several types of clinicians. The goal is not only to restore normal eating behavior, but also to treat medical complications and address any underlying psychological problems.
Nutritional counseling. To break the cycle of bingeing and compensation, patients learn to structure and pace meals, and to adjust daily calorie intake to the amount needed to maintain weight.
Cognitive-behavioral therapy (CBT). The research consistently finds that CBT is the most effective type of psychotherapy for adults with bulimia. This therapy helps patients identify and change distorted thoughts — about themselves and food — that underlie their compulsive behavior, and find better ways to cope with life stresses.
Although CBT can rapidly break the cycle of bingeing and purging, combining it with medication or adding other types of psychotherapy in a stepped fashion, as the patient improves, is more likely to help patients deal with underlying psychological symptoms and avoid relapse.
Interpersonal therapy. This therapy frames problems as a function of difficulties in personal relationships, and so tries to improve the relationships in order to address the eating disorder.
Self-help. Self-help strategies — including new Internet-based modes as well as support groups — might help some patients with bulimia, but the research evidence is not as strong as it is for other therapies. These strategies may be best used in addition to other therapies, rather than on their own.
SSRIs. The only FDA-approved medication for treating eating disorders is fluoxetine (Prozac). Less research has been done about sertraline (Zoloft), but a small randomized controlled trial found that it was also effective in treating bulimia in adults. It may be necessary to try several SSRIs in sequence to find the one that works best for a particular patient.
Although many options exist for treating bulimia, the short-term response rate remains discouragingly low — underscoring the need to be persistent. The long-term outlook is more encouraging. Studies that have followed patients with bulimia 10 years after they received treatment found that 70% had recovered.
October 2009 update