Longitudinal associations between borderline personality disorder and five-factor model traits over 24 years

Abstract

Are five-factor traits and borderline personality symptoms the same features with different names? The existing literature offers reasons to think they are the same and reasons to think they are different. We examined longitudinal associations between these variables in a sample of patients assessed 12 times over 24 years using latent curve models with structured residuals. Mean trajectories for all variables were in the direction of symptom reduction/personality maturation and could be parsed into an initial, rapid improvement phase and a subsequent, gradual improvement phase. We found robust between-person associations among intercepts and long-term slopes of traits and symptoms. Specifically, higher levels of neuroticism as well as lower levels of extraversion, agreeableness, and conscientiousness were associated with higher levels of borderline personality symptoms, and changes in these traits were correlated with reduction in symptoms over time. Associations among time-structured residuals allowed for examinations of within-person deflections from these general trends at briefer (two year) intervals. All variables exhibited robust within-person carry-over effects. Other within-person effects were more specific to certain traits. These results suggest that, despite their distinct theoretical and methodological bases, normal trait and psychiatric diagnostic approaches largely converged on a similar conception of borderline personality.