Five-factor trait instability in borderline relative to other personality disorders.

Borderline personality disorder (BPD) is related to five-factor model (FFM) traits and can be characterized as involving psychological and behavioral instability. A previous study comparing the FFM trait stability across individuals with borderline and other personality disorders found that the BPD group tended to have lower stability, particularly on neuroticism and conscientiousness and the overall configuration of FFM profiles over 6 years, suggesting that associated psychological and behavioral variability may be due to trait variability. The current study was designed to test the degree to which these findings replicate in another sample using different diagnostic and trait measures and extending the measurement period to 10 years. Results are consistent with previous findings in showing lower differential (rank-order) stability on conscientiousness, greater mean-level decreases on neuroticism, lower individual-level stability on conscientiousness, and lower ipsative stability of trait profile configurations among those with BPD. However, unlike the previous study, no differences were observed for differential or individual-level neuroticism or mean-level conscientiousness. Overall, findings show that the instability characteristic of BPD extends into typically stable personality traits, and that it does so with some specificity in terms of which traits are affected and how instability manifests.