Web-based cognitive behavioural treatment benefits individuals with bulimia

A web-based cognitive behavioural self-help intervention demonstrates effectiveness in reducing eating disorder symptoms and illness-related burden in individuals with bulimia nervosa, according to a study.

The study included 154 adults (mean age 29.6 years, 96.8 percent female) who met the diagnostic criteria for bulimia nervosa. These participants were randomly assigned to undergo a web-based cognitive behavioural self-help intervention (n=77) or to a waiting-list control group only having access to routine care (n=77).

The intervention consisted of 12-week modules introducing a diathesis-stress model and then targets key eating disorder mechanisms, allowing participants to work individually on their symptoms.

After 12 weeks of treatment, the intervention group achieved a significantly greater reduction in bulimic episodes—the primary outcome—compared with the control group (Cohen d, −0.48, 95 percent confidence interval [CI], −0.75 to −0.20; p<0.001). Notably, the change observed in the intervention group was driven by a substantial decrease in binge-eating episodes (Cohen d, −0.61, 95 percent CI, −0.89 to −0.33; p<0.001) but not in compensatory behaviours (Cohen d, −0.25, 95 percent CI, −0.51 to 0.02; p=0.21).

In terms of secondary outcomes, the intervention vs control showed superior effects on global eating disorder symptoms (Cohen d, −0.61, 95 percent CI, −0.89 to −0.32; p<0.001) and clinical impairment (Cohen d, −0.62, 95 percent CI, −0.92 to −0.33; p<0.001). No between-group differences were observed for well-being (Cohen d, −0.08, 95 percent CI, −0.37 to 0.22; p>0.99) and work capacity (Cohen d, −0.01, 95 percent CI, −0.68 to 0.66; p=0.99).

In exploratory analyses, the intervention group showed significant changes in self-esteem and emotion regulation difficulties but not in comorbid symptoms.