A placebo-controlled study of fluoxetine in continued treatment of bulimia nervosa after successful acute fluoxetine treatment.

Objective: The efficacy of fluoxetine in the acute management of bulimia nervosa is well established; however, few controlled studies have examined whether continuation of pharmacotherapy provides protection from relapse. This study compared the efficacy and safety of treatment with fluoxetine versus placebo in preventing relapse of bulimia nervosa during a 52-week period after successful acute fluoxetine therapy.

Method: Patients who met DSM-IV criteria for bulimia nervosa, purging type, were assigned to single-blind treatment with 60 mg/day of fluoxetine. After 8 weeks of treatment, patients were considered responders if they experienced a decrease > or =50% from baseline in the frequency of vomiting episodes during 1 of the 2 preceding weeks. Responders were randomly assigned to receive 60 mg/day of fluoxetine or placebo and were monitored for relapse for up to 52 weeks. Patients met relapse criteria if they experienced a return to the baseline vomiting frequency that persisted for 2 consecutive weeks.

Results: Of the 232 patients who entered the acute phase, 150 patients (65%) met response criteria and were randomly assigned to receive fluoxetine (N=76) or placebo (N=74). Fluoxetine-treated patients exhibited a longer time to relapse than placebo-treated patients. Quantitative analysis of other efficacy measures, including frequency of vomiting episodes, frequency of binge eating episodes, Clinical Global Impression severity and improvement scores, the patient's global impression score, and Yale-Brown-Cornell Eating Disorder Scale score, indicated that the efficacy of fluoxetine treatment was statistically superior, compared to placebo. There were no clinically relevant differences in safety between groups. Attrition in this study was high, especially in the first 3 months after random assignment to treatment groups.

Conclusions: Continued treatment with fluoxetine in patients with bulimia nervosa who responded to acute treatment with fluoxetine improved outcome and decreased the likelihood of relapse.