Subtypes of borderline personality features in adolescence: Insights from cross-lagged panel network analysis.

Borderline personality disorder (BPD) is a complex and severe psychiatric condition characterized by emotional, self-image, behavior, and relational instability. While adult BPD heterogeneity has been extensively studied, the phenomenological borderline personality features (BPFs) in adolescence remain uninvestigated. This study aimed to explore the potentially dynamic causal relationships between BPFs in adolescence and identify the subtypes through cross-lagged panel network (CLPN) analysis. Two independent Chinese adolescent samples were followed over 18 months (N₁ = 1,056, M_1age = 15.37, SD1 = 1.86) and 6 months (N₂ = 723, M_2age = 16.84, SD₂ = 0.48) to track BPFs. CLPN modeling was employed to investigate the stability, potential causal relations, and subtypes of adolescent BPFs. The results revealed a relatively stable overall adolescent BPF network structure with some subtle changes over time. Impulsivity emerged as the BPF with the highest out-expected influence, indicating its predictive role for other BPFs. A strong reciprocal causal relationship was observed between impulsivity and affective instability. Based on the CLPN estimation, two distinct BPFs subgroups were spontaneously clustered: externalized-dysregulation subtype (impulsivity, affective instability, and self-harm/suicide) and introjective-disturbance subtype (identity disturbance, chronic emptiness, and stress-related dissociation). The present study tentatively explores a potential typology for adolescent BPF based on these two clusters, which possibly have different pathological mechanisms, and moreover offer insights into the essential construct and clinical intervention of adolescent BPD. (PsycInfo Database Record (c) 2024 APA, all rights reserved).