Self-harm history predicts resistance to inpatient treatment of body shape aversion in women with eating disorders: The role of negative affect.

Although self-harm has been observed among patients with eating disorders, the effects of such tendencies on treatment outcomes are unclear. The current study employed structural equation modeling to (a) evaluate the relationship between self-harm and changes in body dissatisfaction and drive for thinness in a large sample of patients (n = 2061) who underwent inpatient treatment, and (b) to examine whether the relationship between self-harm and changes in body dissatisfaction and drive for thinness during inpatient treatment remains significant when controlling for change in negative affect during treatment. Results revealed that patients with a history of self-harm reported significantly less reduction in body dissatisfaction and drive for thinness following treatment. Patients experiencing less change in negative affect also reported significantly less reduction in body dissatisfaction and drive for thinness after discharge from treatment. However, the association between history of self-harm and reduction in body dissatisfaction and drive for thinness after treatment became non-significant when controlling for change in negative affect. This pattern of findings was also replicated among patients with a primary diagnosis of anorexia nervosa (n = 845), bulimia nervosa (n = 565), and eating disorder not otherwise specified (n = 651). The implications of these findings for delineating the specific role of self-harm in the nature and treatment of eating disorders are discussed.