Obsessive–compulsive personality disorder in radically open dialectical behavior therapy for treatment-refractory depression.

Obsessive-compulsive personality disorder (OCPD) is commonly comorbid with major depressive disorder, and their comorbidity is associated with worsened outcomes and treatment refraction. Radically open dialectical behavior therapy (RO DBT) is a novel transdiagnostic psychosocial intervention. RO DBT targets OCPD-related traits (e.g., maladaptive perfectionism, inflexibility) and has been theorized as an OCPD treatment. This study examined RO DBT efficacy for treatment-refractory depression (TRD), with and without comorbid OCPD. RefraMED was a multisite randomized controlled trial of treatment as usual (TAU) versus RO DBT + TAU for TRD (N = 250). In this secondary data analysis, linear regression predicted 7-month (end of treatment) and 12-month (follow-up) symptoms, controlling for baseline symptoms. Three models examined: (a) outcomes for participants with OCPD (n = 117) comparing RO DBT + TAU and TAU, (b) outcomes among participants receiving RO DBT (n = 162) comparing OCPD and no OCPD, and (c) OCPD diagnosis moderating treatment effects for all participants (N = 250). At 12 months, participants with OCPD had significantly improved emotional approach coping (emotion recognition and communication) and psychological flexibility in RO DBT + TAU (vs. TAU alone; false discovery rate-adjusted ps = .008), with no significant differences observed for depression or interpersonal functioning. OCPD presence did not predict any outcomes within the RO DBT group, nor moderate the effect of treatment on outcomes, suggesting treatment effects were not significantly inhibited by OCPD presence. In conclusion, RO DBT shows promise as a potential evidence-based treatment for OCPD, particularly when comorbid with TRD. Treatment effects were equivalent for those with and without OCPD. Moreover, RO DBT may be particularly beneficial for improving emotional approach coping and flexibility. (PsycInfo Database Record (c) 2025 APA, all rights reserved).