Effect of dialectical behavior therapy on affective symptoms in borderline personality disorder: A systematic review and meta-analysis.

BACKGROUND

Dialectical Behavior Therapy (DBT), originally designed for emotional dysregulation in borderline personality disorder (BPD), has shown effective overall, but its specific effect on depression and anger expression stays underexplored.

OBJECTIVES

This study systematically reviews and meta-analyzes controlled trials analyzing the impact of standard DBT on post-treatment depression and anger expression among adults having BPD.

METHODS

This study performed by searching PubMed, Scopus, and Web of Science through February 24, 2025, for randomized and high-quality non-randomized trials. Eligible studies reported validated, quantitative post-treatment measures of depression or anger expression. Random-effects meta-analyses assessed Cohen's d for depression and anger; Knapp-Hartung adjustments were applied to the anger analysis. Heterogeneity was calculated, and meta-regression tested intervention duration and publication year as moderators for depression.

RESULTS

From 648 records, seven trials met inclusion criteria, spanning 8 weeks to 12 months across outpatient and community settings. DBT presented a moderate statically significant reduction in depression with SMD of -0.59 (95% CI -1.02 to -0.16; p = 0.007; I² = 80.5%). DBT also presented a moderate statically significant reduction in anger expression with SMD of -0.738 (95% CI -1.371 to -0.104, p = 0.023, I² = 83.3%; and 95% -1.779 to 0.304, p = 0.110 with Knapp-Hartung). High heterogeneity and limited trial numbers constrained statistical power.

CONCLUSIONS

Standard DBT demonstrated moderate, directionally consistent improvements in depressive symptoms and anger expression in adults with BPD, supporting its emotion-regulation framework. Larger, multi-site RCTs with standardized outcomes and long-term follow-up are needed to confirm these effects and identify key moderators.