Background: Cognitive-behavioral therapy (CBT) has documented efficacy for the treatment of binge eating disorder (BED). Interpersonal psychotherapy (IPT) has been shown to reduce binge eating but its long-term impact and time course on other BED-related symptoms remain largely unknown. This study compares the effects of group CBT and group IPT across BED-related symptoms among overweight individuals with BED.
Methods: One hundred sixty-two overweight patients meeting DSM-IV criteria for BED were randomly assigned to 20 weekly sessions of either group CBT or group IPT. Assessments of binge eating and associated eating disorder psychopathology, general psychological functioning, and weight occurred before treatment, at posttreatment, and at 4-month intervals up to 12 months following treatment.
Results: Binge-eating recovery rates were equivalent for CBT and IPT at posttreatment (64 [79%] of 81 vs 59 [73%] of 81) and at 1-year follow-up (48 [59%] of 81 vs 50 [62%] of 81). Binge eating increased slightly through follow-up but remained significantly below pretreatment levels. Across treatments, patients had similar significant reductions in associated eating disorders and psychiatric symptoms and maintenance of gains through follow-up. Dietary restraint decreased more quickly in CBT but IPT had equivalent levels by later follow-ups. Patients' relative weight decreased significantly but only slightly, with the greatest reduction among patients sustaining recovery from binge eating from posttreatment to 1-year follow-up.
Conclusions: Group IPT is a viable alternative to group CBT for the treatment of overweight patients with BED. Although lacking a nonspecific control condition limits conclusions about treatment specificity, both treatments showed initial and long-term efficacy for the core and related symptoms of BED.