Developmental Trajectories of Borderline Personality Disorder Symptoms and Psychosocial Functioning in

Major gains toward understanding the emergence of borderline personality disorder (BPD) pathology, which is typically first noted during adolescence, have been made. The present study addresses a gap in our understanding of within-person change in BPD symptoms across adolescence and contributes to the limited literature on outcomes associated with adolescent BPD. Using an at-risk community sample of girls (N=2,450), bivariate latent growth curve models were used to analyze the co-development of BPD symptoms with eight domains of psychosocial functioning (e.g., social skills, sexual behavior) across ages 14-17. Findings revealed moderate to strong effect sizes for the associations between BPD symptoms and every domain of psychosocial functioning, suggesting that the development of BPD was coupled with poorer outcomes across development. These results highlight the increased need for extending advancements in the adult PD literature to research on PDs in adolescence, and for greater recognition of adolescent BPD in clinical settings.