Beyond the Categorical Distinction Between Borderline Personality Disorder and Bipolar II Disorder Through the Identification of Personality Traits Profiles

Abstract

The relationship between borderline personality disorder (BPD) and type-II bipolar disorder (BDII) is not clearly understood. Nevertheless, in clinical practice and research, most efforts focus on establishing a categorical distinction between the two. We propose using personality traits as a more informative strategy to describe them.Methods: Five-Factor Model personality traits were measured in 73 individuals with either BPD or BDII. Latent class cluster analysis was applied to the sample.Results: A three-cluster model resulted the best fit to the data, where all clusters had high neuroticism and low extraversion scores but differed widely on the other traits. The clusters´ boundaries did not match the categorical diagnosis.Conclusions: Our sample showed significant heterogeneity on personality traits, which can have a relevant effect on the outcome of each disorder and that was not captured by the categorical diagnosis. Thus, we advocate for a multivariate approach as a better way to understand the relationship between BPD and BDII.