1 - (SYM 92) Using Network Analysis to Identify Key and Pathway Symptoms Among Sleep Disturbance Symptoms in Eating Disorder Samples and Co-occurring Post-traumatic Stress Disorder

Eating disorders (EDs) are deadly psychiatric disorders, with high rates of comorbidity (Arcelus et al., 2011; DSM-5, 2013). EDs and post-traumatic stress disorder (PTSD) are reported to co-occur in >20% of ED samples (Ferrell et al., 2020). Sleep problems are commonly reported in both EDs (Cooper et al., 2020) and PTSD (van Liempt, 2012). Sleep disturbance may be a clinical marker for illness severity in ED (Bat-Pitault et al., 2020), and feeling tired is shown to be a central bridge symptom to anxiety, worry, and ED symptoms in anorexia nervosa (e.g., Ralph-Nearman et al., 2021). For individuals with PTSD, sleep problems may bidirectionally influence distress and dysfunction, whereby, in the context of trauma exposure, these disruptions increase risk for developing psychopathology, and PTSD symptoms can precede and increase risk for sleep problems (Koffel et al., 2016; Richards et al., 2020). Together research points to sleep disturbances being potential pathways between ED and PTSD symptoms. The aim of the current study was to examine the inter-relationships among ED, PTSD, and sleep disturbance symptoms in ED only vs. ED+PTSD samples. Participants (N=1033) were 15 to 74 years (M_age=22.80; SD=8.27) with an ED who completed assessment of sleep disturbances (i.e., tired/fatigued, difficulty falling/staying asleep, nightmares, changes in sleep), PTSD symptoms, and ED symptoms (i.e., restriction, purging, binge eating, fasting, fear of weight gain, feeling fat). Only 25 participants in the sample did not endorse sleep disturbance symptoms. In all three networks (full sample, ED (n = 434), ED+PTSD (n = 574), PTSD symptoms intrusive thoughts (S = 1.21; .44; .71) and avoid activities (S = .93; .51; .59) were among the top three symptoms with the greatest strength centrality; with the full network included easily startled (S = .92), ED included avoid thinking (S = .45), and ED+PTSD included nightmares (S = .44). Nightmares was the symptom with the greatest bridge expected influence (BEI 2-step) in the full sample (BEI = 1.16), ED (BEI = .41), and ED+PTSD (BEI = .60) networks. Results show that the ED vs. ED+PTSD networks were similar (network invariance [S = .99; p</em> = .11]; global strength [M =.14; p = .32]). This study identifies that sleep disturbances are bridge symptoms among ED and ED+PTSD samples, and that PTSD symptoms are shared core symptoms in ED and ED+PTSD samples. Next steps are to understand how sleep disturbances relate to and predict ED and other pathology. Importantly, this study suggests that sleep and PTSD symptoms may be a key to target in ED treatment.