Introduction
disordered eating behaviors, anxiety-based, decreases in disordered eating behaviors, anxiety, Eating disorders, anxiety disorders, weight gain, psychiatric, weight loss
Eating disorders (EDs) are severe psychiatric illnesses characterized by disrupted consumption of food (e.g., restrictive or loss of control [LOC] eating) and often involve overvaluation of one’s shape and weight, a drive for thinness, and body image disturbances [A clearer understanding of maintaining factors in binge-spectrum EDs would allow for development of more targeted, specific interventions. Fear-based maintaining factors in EDs, such as fear of weight gain or “fatness” and its consequences,Fear of weight gain may originate from an overvaluation of one’s shape and weight—a core symptom across binge-spectrum EDs [In addition to being a central symptom for EDs, fear of weight gain may also be motivating disordered eating behaviors through a cycle of avoidance, as is seen in anxiety disorders [Theory supports conceptualization of EDs using an anxiety-based model, but little research exists on the temporal relationship between fear and disordered eating behaviors. For example, fear of weight gain may lead to restrictive eating, thus resulting in LOC episodes. Similarly, fear of weight gain may increase attention to threat (e.g., foods high in fat content), leading to an attempt to avoid these foods followed by a binge episode containing these foods. A better understanding of this link would clarify whether targeting fear of weight gain directly in treatment should result in decreases in disordered eating behaviors. Additionally, many patients with EDs place value on fear of weight gain, as they believe it will lead to achievement of the weight loss goal and/or protect them from the feared outcome of weight gain [CBT-E does not specifically or explicitly target fear of weight gain. Although CBT-E is not an exposure-based treatment—such as the first-line interventions for targeting fears in other populations (e.g., anxiety, OCD)—there are a number of components to CBT-E that may inherently require confrontation of fears [The current study sought to clarify whether CBT-E produces changes in fear of weight gain and to better understand whether fear of weight gain is predictive of disordered eating behaviors and treatment outcomes during 12 sessions of modified CBT-E for binge-spectrum EDs. Modified CBT-E included self-monitoring, regular eating, overvaluation of weight/shape, reducing restriction/restraint, and addressing mood-related changes to eating. We predicted that (1) fear of weight gain would decrease over the course of treatment given the inherent confrontation of fears involved in CBT-E, (2) changes in fear of weight gain over treatment would be moderated by diagnosis (i.e., BN-spectrum, BED), (3) within-person increases in fear of weight gain would be associated with higher frequencies of LOC eating episodes in the following week, and (4) between-person, those with a higher fear of weight gain would experience a higher frequency of LOC episodes. Additionally, many individuals with EDs hold the metacognitive belief that their fear of weight gain is critical to evading actual weight gain. To understand whether fear of weight gain was actually associated with weight change, we explored the bidirectional relationship between fear of weight gain and BMI within- and between-person across treatment.