Objective: This randomized controlled trial tested the effectiveness of an 18-month mentalization-based treatment (MBT) approach in an outpatient context against a structured clinical management (SCM) outpatient approach for treatment of borderline personality disorder.
Method: Patients (N=134) consecutively referred to a specialist personality disorder treatment center and meeting selection criteria were randomly allocated to MBT or SCM. Eleven mental health professionals equal in years of experience and training served as therapists. Independent evaluators blind to treatment allocation conducted assessments every 6 months. The primary outcome was the occurrence of crisis events, a composite of suicidal and severe self-injurious behaviors and hospitalization. Secondary outcomes included social and interpersonal functioning and self-reported symptoms. Outcome measures, assessed at 6-month intervals, were analyzed using mixed effects logistic regressions for binary data, Poisson regression models for count data, and mixed effects linear growth curve models for self-report variables.
Results: Substantial improvements were observed in both conditions across all outcome variables. Patients randomly assigned to MBT showed a steeper decline of both self-reported and clinically significant problems, including suicide attempts and hospitalization.
Conclusions: Structured treatments improve outcomes for individuals with borderline personality disorder. A focus on specific psychological processes brings additional benefits to structured clinical support. Mentalization-based treatment is relatively undemanding in terms of training so it may be useful for implementation into general mental health services. Further evaluations by independent research groups are now required.