Low Fasting Oxytocin Levels Are Associated With Psychopathology in Weight-Recovered Anorexia Nervosa

Abstract

Anorexia nervosa (AN), a psychiatric disorder characterized by restriction of food intake despite severe weight loss, is associated with increased comorbid anxiety and depression. Secretion of oxytocin, an appetite-regulating neurohormone with anxiolytic and antidepressant properties, is abnormal in AN. The link between oxytocin levels and psychopathology in AN has not been well explored. We performed a cross-sectional study of 80 women ages 18-45 years old [(20 AN, 26 weight recovered AN (ANWR) and 34 healthy controls (HC)] investigating the relationship between basal oxytocin levels and disordered eating psychopathology, anxiety, and depressive symptoms. Fasting serum oxytocin levels were obtained and the following self-report measures were used to assess psychopathology: Eating Disorder Examination Questionnaire, State Trait Anxiety Inventory, and Beck Depression Inventory – II. We found that fasting oxytocin levels were low in ANWR compared to HC (p=0.0004). In ANWR but not AN, oxytocin was negatively associated with disordered eating psychopathology (r=-0.39, p=0.0496) and anxiety symptoms (state anxiety: r=-0.53, p=0.006; trait anxiety: r=-0.49, p=0.01). Furthermore, ANWR with significant disordered eating psychopathology, anxiety symptoms, or depressive symptoms had lower oxytocin levels compared to those with minimal or no symptoms. We conclude that dysregulation of oxytocin pathways may contribute to persistent psychopathology after weight recovery from anorexia nervosa.