The functionality of non-suicidal self-injurious behavior by adolescent girls and young women with eating disorders

Theoretical background: Recent research shows that a significant proportion of girls and women with eating disorders have non-suicidal self-injurious behavior. Because of their frequent co-occurrence, it is to be assumed that self-injurious behavior fulfills important functions in the context of eating disorders. Despite the growing interest in self-injurious behavior in people with eating disorders in the recent years, little is known about these functions so far. Thus, it is still unclear whether there are differences between the various eating disorders in functionality of self-injurious behavior and which factors facilitate the use of the different functions. Moreover, the existence of eating disorder specific functions is not adequately clarified. Objective: The aim of the present work was to study the existence of eating disorder specific functions and whether girls and women with restricting anorexia nervosa, binging/purging anorexia nervosa, bulimia nervosa, and binge eating disorder use self-injurious behavior with different frequency for affective regulation. Moreover, the extent to which eating disorder features facilitate the various functions of self-injurious behavior was analysed among girls and women with eating disorders taking into account depressive symptoms and borderline-typical cognitions. Methods: The study participants were 142 girls and young women from eating disorder clinics and residential groups diagnosed with restricting anorexia nervosa, binging/purging anorexia nervosa, bulimia nervosa, and binge eating disorder. Self-injurious behavior and its functions as well as eating disorder, depression and borderline symptoms were assessed cross-sectional by means of self-report questionnaires. Results: Bulimics and binge eaters hurt themselves significantly more often than restrictive anorectics, to reduce negative high-arousal emotions such as anger and rage. The existence of eating disorder functions, such as "suppression of fear of gaining weight", could be confirmed. The striving for thiness, regardless of depression and borderline-thinking, promotes these special functions. It was found that functions of self-injurious behavior such as "regulation of low-arousal emotions", "self-punishment/expression of self-hatred", and "anti-dissociation" are facilitated by comorbid borderline-thinking patterns. The effect of socially prescribed perfectionism on the social functions is moderated by the experience of ineffectiveness. Conclusion: The functionality of self-injurious behavior differs among the different eating disorders. In particular borderline-typical thoughts facilitate the use of intrapsychic functions of self-injurious behavior in girls and women with eating disorders. In contrast, social functions are faciltated by the interaction of eating disorder features perfectionism and ineffectiveness. The primary symptom of eating disorder, in the form of strive for thinnes, presumably contributes to the development of self-injurious behavior for regulation of eating disorders