A262 Negative Affect and Loss of Control Eating among Bariatric Surgery Patients: A Preliminary Ecological Momentary Assessment Investigation

Evidence suggests that loss of control (LOC) eating impacts weight loss outcomes following bariatric surgery; however, mechanisms explaining the development and/or maintenance of LOC remain unclear. Research utilizing ecological momentary assessment (EMA) has demonstrated prospective relationships between negative affect (NA) and LOC within the eating disorder literature, but this effect has not been examined within a bariatric surgery population using momentary data. This study explored whether higher NA led to greater LOC among bariatric surgery patients and if the relationship differed before versus after surgery. Fourteen pre- and 17 post-RYGB patients completed two weeks of EMA signaling. Participants responded to seven signals each day and rated their current mood and experience of LOC since the last signal. Results from a Generalized Linear (GEE) model demonstrated that higher NA predicted higher ratings of LOC at the next signal (B = .223, χ2(1) = 58.87, p < .001) and that group had a moderating effect (B = -.163, χ2(1) = 15.19, p < .001), wherein the post-surgery had a stronger association between NA and LOC relative to the pre-surgery group. Post-hoc analyses among the post-surgery group demonstrated that body mass index (BMI) change, percent excess BMI loss, and percent total body weight loss moderated the relationship between NA and LOC (p’s < .05), such that the relationship between NA and LOC was stronger for those who had experienced less weight loss. These preliminary findings implicate NA as a possible target for improving weight loss outcomes. Limitations and future directions will be discussed.