Borderline personality features predicting depressive symptom trajectories among Chinese university students: The mediating role of difficulties in emotion regulation.

BACKGROUND

Despite established heterogeneity in depressive trajectories, the psychological mechanisms driving adverse developmental courses remain understudied. This study examined how borderline personality features (BPF) and difficulties in emotion regulation (DER) predict longitudinal symptom paths.

METHODS

A large-scale, three-wave longitudinal design was utilized with 4884 adult university students (Mage = 19.28, SD = 0.84;82.1% female). Latent class growth analysis (LCGA) identified symptom trajectories. Multinomial logistic regression and mediation analysis within the 3-step framework were used to examine baseline predictors and internal mechanisms.

RESULTS

Three distinct trajectories were identified: Low-Decreasing (57.8%), Moderate-Increasing (35.6%), and High-Quickly Increasing (6.7%). Baseline BPF and DER significantly predicted membership in adverse trajectories. Notably, the predictive effect of BPF was significantly mediated by DER. Additionally, male sex and older age were identified as significant risk factors for following the most severe escalation paths.

CONCLUSION

The findings highlight a BPF-DER internal risk cascade. Early interventions should prioritize enhancing emotion regulation skills alongside providing vocational guidance and economic assistance to mitigate long-term depressive burdens in high-risk students.