The University of Fukui achieves improvement of female bulimia nervosa through cognitive behavioral therapy

A research group led by Assistant Professor Sayo Hamatani and Associate Professor Yoshifumi Mizuno from the Research Center for Child Mental Development at University of Fukui, in collaboration with Kagoshima University Hospital and Linköping University (Sweden), announced on August 25 that they have developed a guided internet-based cognitive behavioral therapy for bulimia nervosa tailored to Japanese culture and demonstrated its effectiveness in a multicenter randomized controlled trial involving 61 female patients. The widespread adoption of guided internet-based cognitive behavioral therapy is expected as a new treatment option that reduces the burden of outpatient visits and allows patients to receive specialized treatment at home. The results were published in the August 5 issue of JAMA Network Open.

Bulimia nervosa is a mental disorder characterized by uncontrollable eating behavior, consuming large amounts of food in short periods. Excessive concern about body weight leads to repeated binge eating and compensatory behaviors (such as vomiting and laxative abuse), affecting women at a gender ratio of 10 to 1. Its prevalence is increasing, with risks of chronicity and serious physical and psychological health consequences. Up to 3% of women develop the condition during their lifetime, with mortality risk increasing approximately five-fold.

However, opportunities to receive effective treatment are limited, and, particularly in Asia (including Japan), the effectiveness and acceptability of guided internet-based cognitive behavioral therapy for women with bulimia nervosa had not been sufficiently validated. Cognitive behavioral therapy is a psychotherapy that focuses on identifying cognitive phenomena and behavioral patterns that cause people to maintain psychological and behavioral problems and transforming them into adaptive ones.

The research group validated the effectiveness and acceptability of this treatment method adapted to Japanese culture with 61 women diagnosed with bulimia nervosa who were receiving outpatient care at 6 university hospitals and 1 national center nationwide. The trial was conducted from August 2022 to July 2024 with cooperation from these 7 institutions in Japan and a Swedish university.

As a result, compared with the usual care only group (outpatient care only), the guided internet-based cognitive behavioral therapy group showed significant reductions in the frequency of binge eating and compensatory behaviors (vomiting, laxative abuse, etc.). An average reduction of approximately 10 episodes was observed, along with confirmed improvements in severity, and remission rates were significantly higher.

The treatment method developed in this study involves completing one module per week over 12 weeks for treatment completion. The schedule is designed so that one task can be completed in approximately 15 minutes. The 12 modules consist of: psychoeducation and case formulation, mindfulness meditation, metacognitive training, attention bias and body image modification, behavioral experiments to test binge urges, establishment of healthy eating habits, creation of anxiety hierarchies and graded exposure, cue exposure for binge eating and compensatory behaviors, restructuring of negative self-statements, rewriting traumatic memories, rewriting residual beliefs, and relapse prevention.

Using online methods, patients can receive treatment at their own pace and feel secure through therapist support via chat. 72.4% responded that they would "like to receive this treatment again when facing difficulties in the future," demonstrating very high patient satisfaction.

Journal Information
Publication: JAMA Network Opens
Title: Guided Internet-Based Cognitive Behavior Therapy for Women With Bulimia Nervosa
DOI: 10.1001/jamanetworkopen.2025.25165