A new study published in Behaviour and Research Therapy examined the efficacy of cognitive behavior therapy (CBT) for women with a variety of purging behaviors. The study compared 3 groups: those who engaged in self-induced vomiting, those who engaged in multiple purging methods (i.e., laxatives and diuretics), and those who engaged in restrained eating and/or excessive exercise as a means of weight control. First, participants in each group self-reported on their shape and weight concerns, subjective feelings about bulimic episodes, and eating disorder symptoms. Those individuals who engaged in self-induced vomiting or purging methods reported a longer duration of their disorder, more objective bulimic episodes, more severe shape and weight concerns, higher scores for eating disorder symptoms, and high depressive scores than those who did not engage in purging behaviors. A portion of the sample (75%) then completed 20 weeks of CBT. At post-treatment, all three groups showed significant reductions in objective and subjective bulimic episodes, weight and shape concerns, anxiety and depressive symptoms, vomiting, laxative and diuretic use, excessive exercising, and restrained eating. Researchers concluded that despite the greater clinical severity associated with the presence of purging behaviors in eating disorders, these variable do not impact the efficacy of inpatient CBT.
Dalle Grave, R., Calugi, S. & Marchesini, G. (2009). Self-induced vomiting in eating disorders: Associated features and treatment outcome. Behaviour Research and Therapy, 47, 680-684.