UNDERSTANDING CLINICAL HETEREOGENEITY IN ANOREXIA NERVOSA: SOCIOEMOTIONAL PROCESSES, MOTIVATION, TREATMENT TRAJECTORIES

State of the art and purpose: Anorexia Nervosa (AN) is a severe psychiatric disorder with often unsatisfactory treatment outcomes. Understanding the factors underlying heterogeneity in clinical presentation and treatment response is essential for improving personalized care. This thesis applied up-to-date statistical methods to areas identified as relevant in AN: socioemotional processes (study 1), motivation to change (study 2), and in-treatment symptoms trajectories (study 3). Methods: Study 1 assessed multimodal emotion recognition and emotional competence in individuals with AN (n=128) and healthy controls (n=140), using signal detection theory and Bayesian methods. Study 2 examined motivation to change in inpatients and outpatients with AN (n=300) through exploratory graph analysis. Study 3 applied growth mixture models to weekly measures of weight and depressive trajectories during inpatient treatment for AN (n=156, Danish sample). Results: Study 1: across 14 ecologically assessed emotion, only fear recognition difficulties were clearly associated with AN. Interpersonal emotional comprehension emerged credibly and specifically associated with emotion recognition ability. Study 2: network analysis identified two motivational dimensions, which were differently associated with weight change during inpatient treatment. Study 3: three body mass index trajectories and two depressive trajectories emerged from repeated longitudinal data collection, with unique relationship with baseline predictors. Notably, a severe and non-improving depressive trajectory showed relationship with individual history of trauma. Additions to the current state of the art: Study 1 provides the first concurrent assessment of multimodal emotion recognition and emotional competence in AN. Study 2 provides the Italian validation of the Anorexia Nervosa Stages of Changes questionnaire and the first network-based assessment of motivation to change. Study 3 represents the first assessment of weekly depressive trajectories in hospitalized individuals with AN