Abstract
Although loss of control (LOC) while eating is a core construct of bulimia nervosa (BN), questions remain regarding its validity and prognostic significance independent of overeating. We examined trajectories of objective and subjective binge eating (OBE and SBE, respectively; i.e., LOC eating episodes involving an objectively or subjectively large amount of food) among adults participating in psychological treatments for BN-spectrum disorders (n = 80). We also explored whether changes in the frequency of these eating episodes differentially predicted changes in eating-related and general psychopathology and, conversely, whether changes in eating-related and general psychopathology predicted differential changes in the frequency of these eating episodes. Linear mixed models with repeated measures revealed that OBE decreased twice as rapidly as SBE throughout treatment and 4-month follow-up. Generalized linear models revealed that baseline to end-of-treatment reductions in SBE frequency predicted baseline to 4-month follow-up changes in eating-related psychopathology, depression, and anxiety, while changes in OBE frequency were not predictive of psychopathology at 4-month follow-up. Zero-inflation models indicated that baseline to end-of-treatment changes in eating-related psychopathology and depression symptoms predicted baseline to 4-month follow-up changes in OBE frequency, while changes in anxiety and self-esteem did not. Baseline to end-of-treatment changes in eating-related psychopathology, self-esteem, and anxiety predicted baseline to 4-month follow-up changes in SBE frequency, while baseline to end-of-treatment changes in depression did not. Based on these findings, LOC accompanied by objective overeating may reflect distress at having consumed an objectively large amount of food, whereas LOC accompanied by subjective overeating may reflect more generalized distress related to one's eating- and mood-related psychopathology. BN treatments should comprehensively target LOC eating and related psychopathology, particularly in the context of subjectively large episodes, to improve global outcomes.