Emotional cognition in patients with borderline personality disorder and patients with bipolar disorder type II: Evidence for transdiagnostic and differential diagnostic differences?

INTRODUCTION: Distinguishing borderline personality disorder (BPD) from bipolar disorder type II (BD-II) is challenging due to overlapping symptoms, often leading to misdiagnosis and suboptimal treatment. This study explored transdiagnostic and diagnostic differences in emotional cognition between patients with BPD, patients with BD-II and healthy controls (HC).

EXPERIMENTAL PROCEDURES: The sample included 35 patients with BPD, 35 with BD-II in remission, and 35 HC. Emotional cognition was assessed with virtual reality (VR) and the Facial Expression Recognition Task. Participants completed questionnaires regarding occupational and social functioning, quality of life, and childhood trauma. Transdiagnostic differences were explored by comparing each patient group to HC, and diagnostic differences were examined between BPD and BD-II. Regression analyses evaluated the impact of childhood trauma on emotional cognition.

RESULTS: Transdiagnostically, patients showed poorer emotion regulation in negative VR scenarios compared to HC, but there were no differences in emotional face processing. Differential diagnostically, patients with BPD were slower at identifying emotional faces than those with BD-II, with trends towards lower accuracy. No significant differences were observed between patients with BPD and patients with BD-II in VR scenarios. Across participants, childhood trauma predicted blunted emotion ratings and slower facial emotion recognition.

DISCUSSION: Impaired emotion regulation may serve as a transdiagnostic biomarker for BPD and BD-II, while slower emotion recognition may distinguish BPD from BD-II. Across participants, childhood trauma predicted blunted emotion ratings and slower facial emotion recognition, underscoring its lasting impact.