3 - (SYM 92) Negative Affect Mediates the Association Between Nightly Sleep and Next-day Binge Eating

Sleep disturbance has a high prevalence among those with eating disorders and has been demonstrated to interfere with treatment recommendations. A growing body of literature has linked sleep disturbance with increased engagement in binge eating (BE; i.e., eating episodes accompanied by a subjective sense of loss-of-control over eating) and increased negative affect both cross-sectionally and longitudinally. In turn, negative affect is also predictive of increased risk for BE both cross-sectionally and longitudinally. However, no research to date has rigorously examined whether the effect of sleep disturbance on BE can be explained by increases in negative affect. Identification of psychological mechanisms linking sleep disturbance and BE would open novel pathways for intervention and assessment. Participants were 107 adults with clinically significant BE (M_age = 41.88, SD = 14.05, 80.41% female) who completed ecological momentary assessment surveys assessing sleep disturbance (morning surveys only), negative affect, and BE six times per day for up to 14 days. Mediation models evaluated whether there was an indirect effect of within-person increases in pre-binge negative affect on the association between within-person increases in sleep disturbance (i.e., poor sleep quality, heightened morning fatigue, and short sleep duration) and next-day binge eating. Within-person increases in negative affect mediated the association between within-person decreases in sleep quality (Est = -0.019, S.E. = 0.009, p = 0.028) and next-day BE, and within-person increases in morning fatigue (Est = 0.020, S.E. = 0.009, p = 0.024) and next-day BE. Pre-binge negative affect did not mediate the association between sleep duration and next-day BE. Findings suggest that negative affect may be a mechanism of the link between sleep disturbance and BE. These findings offer preliminary support for adjunctive treatments targeting both sleep disturbance and negative affect in reducing BE and improving treatment outcomes among individuals with eating disorders. Future research should include objective assessment of sleep and test the additive benefit of interventions targeting sleep to address BE.