ORIGINAL ARTICLE Eating disorder psychopathology in adults and adolescents with anorexia nervosa: A network approach Simona Calugi PhD | Massimiliano Sartirana PsyD | Arianna Misconel PsyD | Camilla Boglioli PsyD | Riccardo Dalle Grave MD Department of Eating and Weight Disorders, Villa Garda Hospital, Garda, Italy Correspondence Simona Calugi, Department of Eating and Weight Disorders, Villa Garda Hospital, via Monte Baldo, Garda 89 I-37016, Italy. Email: si.calugi@gmail.com Action Editor: Ruth Weissman Abstract Objective: The aim of this study was to assess and compare eating disorder feature networks in adult and adolescent patients with anorexia nervosa. Methods: Patients seeking treatment for anorexia nervosa in inpatient and outpa- tient settings were consecutively recruited from January 2008 to September 2019. Body mass index was measured, and each patient completed the Eating Disorder Examination Questionnaire. Results: The sample comprised 547 adolescent and 724 adult patients with anorexia nervosa. Network analysis showed that in both adults and adolescents, the most central and highly interconnected nodes in the network were related to shape over- valuation and desiring weight loss. The network comparison test identified similar global strength and network invariance, confirming the similarity of the two network structures. Discussion: The network structures in adult and adolescent patients with anorexia nervosa are similar, and lend weight to the cognitive behavioral theory that overvalu- ation of shape and weight is the core feature of anorexia nervosa psychopathology. KEYWORDS adolescent, adult, desiring weight loss, eating disorder psychopathology, feeling fat, shape overvaluation 1 | INTRODUCTION Available data indicate that treatment outcomes in anorexia nervosa are generally better in adolescents than in adults (Ackard, Richter, Egan, & Cronemeyer, 2014; Ambwani et al., in press; Calugi, Dalle Grave, Sartirana, & Fairburn, 2015; Dalle Grave, Calugi, Doll, & Fairburn, 2013; Fairburn, 2005). It has been hypothesized that these differences in treatment outcome could be due to the clinical impact of neuroprogression (Treasure, Stein, & Maguire, 2015) and habit for- mation (Walsh, 2013) or to the fact that adolescent patients have more structured social networks and a briefer duration of illness than adults (Calugi et al., 2015). However, it is also possible that some psy- chopathological differences between adults and adolescents with anorexia nervosa could explain these findings. Indeed, a study comparing the clinical presentation of adults and adolescents with anorexia nervosa found that adolescents had a shorter period of, but more rapid, weight loss, indicative of an illness of shorter duration, but also less severe eating disorder psychopathol- ogy severity; this led to the suggestion that these two characteristics could explain why they are more amenable to treatment than adults (Fisher, Schneider, Burns, Symons, & Mandel, 2001). Nonetheless, additional research examining the differences in eating disorder psy- chopathology between adults and adolescents with anorexia nervosa is needed to clarify the relationship between specific eating disorder psychopathology features in these two groups of patients. Eating disorder feature associations and relative contribution to psychopathology have traditionally been modeled using empirical approaches (e.g., latent class/profile analysis, factor analysis, structural Received: 20 December 2019 Revised: 17 March 2020 Accepted: 17 March 2020 DOI: 10.1002/eat.23270 Int J Eat Disord. 2020;1–12. wileyonlinelibrary.com/journal/eat © 2020 Wiley Periodicals, Inc. 1