(PS8-A19) Impact of Psychiatric Comorbidity, Childhood Adversities, and Suicidality on Eating Disorder Symptomatology in Adults with Anorexia Nervosa and Atypical Anorexia Nervosa

Although distinct diagnoses, anorexia nervosa (AN) and atypical AN (AAN) share a number of features, including intense fear of weight gain, body image disturbance, and concerning weight loss. Indeed, growing evidence suggests that individuals with AAN demonstrate similar levels of malnutrition, relapse rates, and mortality as those with AN. Across eating disorder (ED) diagnoses, psychiatric comorbidity, childhood adversities, and suicidality are common and associated with increased psychopathology and treatment dropout. Few studies, however, have differentially evaluated the prevalence and effect of these risk factors on treatment outcomes for individuals with AN and AAN. This study evaluated 154 adults (AN: N=95, AAN: N=59) receiving treatment in a partial hospitalization program (PHP) for EDs. Demographic variables on suicidal ideation, history of suicide attempts, abuse, trauma, and comorbid psychiatric diagnoses were derived from initial consultation with a psychiatrist at admission. Participants also completed a battery of self-report questionnaires at admission and discharge, including the Eating Disorder Examination – Self-Report Questionnaire (EDE-Q). No significant group differences were found for any of these variables, indicating that both groups experienced similar levels of childhood adversity, self-harm, suicidality, and eating disorder psychopathology.  We investigated changes on the EDE-Q for those with AN and AAN from admission to discharge by conducting multiple repeated measures analyses of variance (ANOVAs) with diagnosis and other risk factors as between-subjects factors. We found a significant main effect for time (F(1, 1) = 32.83, p < .001), but not a significant time × diagnosis interaction, indicating that both groups improved at a similar rate. Additionally, we found a significant interaction effect for time × lifetime ideation of suicide (F(1, 1) = 4.99, p =.028), indicating that those with no history of suicidal ideation experienced better treatment outcomes. These findings indicate that participants with AN and AAN entering a PHP for EDs experience similar levels of psychiatric comorbidity, childhood adversities, and suicidality, and they demonstrate similar decreases on the EDE-Q over the course of treatment. Further research with a larger, more diverse sample is warranted to evaluate these variables as predictors of treatment outcomes.