4 - (IOP 34) Maladaptive Posttraumatic Beliefs Predict Later Disordered Eating Behaviors

Previous researchers have theorized that posttraumatic stress disorder (PTSD) symptoms may play a crucial role in maintaining an eating disorder (ED) for individuals with this comorbidity. Specifically, ED behaviors such as food restriction, binge eating, and purging are thought to help individuals avoid distressing memories, thoughts, and feelings associated with traumatic events, thus perpetuating both the ED and PTSD. Alternatively, trauma-related disrupted belief systems may lead to or exacerbate pre-existing negative beliefs about the body, leading to ED behaviors as attempts to control shape and weight. However, these proposed mechanisms are largely theoretical and have rarely been tested with empirical data. The aim of the current study was to explore whether PTSD-related beliefs predicted later ED behaviors and body dissatisfaction. Fifty undergraduates with elevated PTSD and ED symptoms were recruited from the US for an ecological momentary assessment (EMA) study. At baseline, participants completed a questionnaire measuring PTSD-related beliefs about safety, self, and others. During the EMA protocol, participants reported food restriction, loss of control eating, overeating, purging, and body dissatisfaction six times a day for two weeks. Multilevel modeling was used to assess the between-subjects effects of PTSD-related beliefs and later ED behaviors. Results indicated that maladaptive safety beliefs at baseline predicted greater restriction (b = 0.05, p = .031), self-related maladaptive beliefs predicted greater body dissatisfaction (b = 0.12, p < .001), and maladaptive beliefs about others predicted greater restriction (b = 0.06, p = .003) and greater overeating (b = 0.04, p = .020). This study provides partial support for purported ED-PTSD mechanisms. Maladaptive beliefs about the self predicted later body dissatisfaction, supporting the idea that self-criticism and low self-worth contribute to shape and weight concerns. Beliefs about the world as dangerous and others as untrustworthy both predicted later restriction, potentially reflecting attempts to suppress these upsetting thoughts. Finally, mistrust in others also predicted overeating. Emotion regulation is often learned with and supported by the social environment; if an individual’s relationships are impaired due to maladaptive beliefs about others, overeating could serve as an attempt to regulate negative emotions in the absence of outside aid. Future research should explore within-subjects effects of cognition on ED behavior.