Temperament, but not childhood trauma, distinguishes borderline personality disorder from bipolar disorder and ADHD.

Background: The aim of this study was to investigate if temperament and experience of childhood trauma differed between young psychiatric patients with borderline personality disorder (BPD), bipolar disorder (BD) and attention-deficit/hyperactivity disorder (ADHD).

Methods: Diagnoses were based on the Structured Clinical Interview for DSM Axis I and Axis II. Temperament was assessed by the Temperament and Character Inventory (TCI) and childhood trauma by the Early Trauma Inventory-Self Report-Short Form (ETI-SR-SF). Temperament and childhood trauma were compared between the BPD group ( = 19) and the non-BPD group (BD/ADHD) ( = 95). Interactions between trauma and temperament were evaluated using a logistic regression model with a BPD diagnosis as outcome variable.

Results: Participants in the BPD group showed higher novelty seeking (NS) and harm avoidance (HA). Traumatic experiences in childhood were common but the BPD group differed very little from the others in this regard. The interaction between temperament and trauma had low explanatory power for a BPD diagnosis in this sample.

Conclusion: Temperament might be useful to distinguish BPD when symptoms of impulsivity and affective instability are evaluated in psychiatric patients. The results from the interaction analysis support the multifactorial background to BPD.