Anorexia Nervosa and Emotional Dysregulation: A Longitudinal Study on the Characteristics and Clinical Implications in a Group of Female Adolescents

Background: Anorexia nervosa (AN) is a severe eating disorder occurring most frequently in adolescence, characterized by a high prevalence of psychiatric comorbidity. Emotional dysregulation (ED) refers to a transdiagnostic construct that often drives disordered eating behavior. The present study aimed to evaluate differences and similarities in the clinical presentation and response to treatment of young AN patients with high levels of ED (AN+ED) and with low levels of ED (AN−ED). Methods: A total of 40 female inpatients aged between 12 and 18 years were consecutively recruited and subdivided into two groups (AN+ED: n = 21; AN−ED: n = 19), based on the median of the subscale Affective Instability (AI) of the Reactivity, Intensity, Polarity and Stability questionnaire—youth version (RIPoSt-Y). At the recruitment (T0), and after 6 months (T1), the Body Mass Index (BMI) was calculated, and questionnaires and scales were administered to assess (a) the general functioning; (b) the severity of the eating disorder; and (c) the associated psychopathology. Results: At T0, an independent-samples t-test showed that the AN+ED group was characterized by a significantly greater impairment in clinical functioning and a greater severity of both the eating disorder and the associated psychopathology compared to the AN−ED group. At T1, the AN+ED group also showed significantly higher levels of cyclothymic, depressive, and anxious symptoms than the AN−ED group. Moreover, repeated-measures ANOVAs revealed a statistically marked improvement over time of the bulimic behaviors in the AN+ED group only. Conclusions: The present study underscored distinctive clinical features in AN patients with high and low levels of ED. Specifically, the AN+ED group was characterized by a most likely severe clinical phenotype that requires tailored intervention strategies.