(PS5-46) Chronotype and Eating Disorder Symptomatology: A Systematic Review

Abstract Text: Sleep disturbances are elevated among people with eating disorders (EDs), with about half of women with EDs endorsing them. Furthermore, sleep disturbances are also associated with more frequent engagement in ED behaviors. One reason for elevated sleep problems among people with EDs could be related to chronotype. Classified as either morningness or eveningness, chronotype is an individual’s natural predisposition for the majority of sleep and activity patterns to occur in the morning or evening. Chronotype may be related to ED pathology through its influence on appetite and consumption, as ED behaviors may be reinforced through an individual’s diurnal preference. For example, individuals with eveningness chronotype may experience lack of appetite in the morning or increased appetite in the evening. This may result in periods of food restriction early in the day, and increased rates of binge-eating later in the evening. Therefore, investigating chronotype may contribute to a better understanding of ED maintenance factors, as well as identify potentially vulnerable populations for EDs and offer intervention targets for treatment. We conducted a systematic review of studies investigating associations between chronotype and eating disorder symptoms. Our research questions were: 1) Is chronotype associated with ED symptom severity and 2) Is chronotype associated with ED diagnosis? A search between January 1994-December 2024 of EmBase, PsychINFO, and PubMed retrieved English-language papers studying potential associations between chronotype and ED symptoms in clinical and non-clinical samples. All studies were screened for inclusion at each stage by two independent raters using Covidence software. Out of thirty-two eligible studies, twenty-two reported a significant association between chronotype and ED symptoms. The eveningness chronotype was more commonly associated with binge-eating, loss of control eating, bulimic behaviors, and night eating syndrome symptoms. Conversely, the morningness chronotype was associated with cognitive restraint, drive for thinness, and restrictive eating. Results suggest that chronotype may be associated differentially between restrictive and binge-eating symptom presentations. These findings highlight chronotype as a potential mechanism underlying ED pathology. Future research should investigate whether interventions related to sleep preferences can be useful in treatments for ED populations.