Oxytocin and rejection sensitivity: A comparative biomarker study in women with borderline personality and eating...

Emotional dysregulation is a hallmark feature of borderline personality disorder (BPD) and eating disorders (ED), which impacts the individuals' well-being and functioning. Oxytocin dysregulation has been involved in social cognition deficits associated with these disorders.

We conducted a study including a total 108 women categorized into 3 groups: 50 with eating disorders (ED), 35 with borderline personality disorder (BPD), and 23 healthy controls. Psychopathological profiles were assessed using the Bulimic Investigatory Test Edinburgh (BITE), the Eating Attitude Test 40 (EAT-40), the Barratt Impulsiveness Scale (BIS-11), and the Rejection Sensitivity Questionnaire (RSQ). Plasma oxytocin levels and oxytocin receptor expression were measured as well.

BPD patients exhibited significantly lower plasma oxytocin levels vs ED patients and healthy controls. However, oxytocin receptor expression did not differ significantly across the groups. Oxytocin levels were positively associated with rejection sensitivity, particularly in BPD patients.

Our findings suggest a potential role of oxytocin dysregulation in emotional dysregulation and rejection sensitivity, particularly in BPD. Higher oxytocin levels in ED patients may serve as a compensatory mechanism to mitigate challenges in interpersonal relationships. These results highlight the importance of personalized therapeutic interventions targeting oxytocin dysregulation in the management of ED and BPD.