The Short-Term MBT Project (MBT-RCT)

Short-term Versus Long-term Mentalization-based Therapy for Outpatients With Subthreshold or Diagnosed Borderline Personality Disorder: a Randomized Clinical Trial

The study will evaluate the benefitial and harmful effects of short-term (20 weeks) compared to long-term (14 months) mentalization-based therapy for outpatients with subthreshold or diagnosed borderline personality disorder.

Psychotherapy for borderline personality disorder is often lengthy and resource-intensive. Mentalization-based therapy is an example of an evidence-based treatment that currently has empirical support as an 18-months outpatient program for borderline personality disorder. However, this duration is rarely available, and the long and costly treatment combined with a highly prevalent disorder result in insufficient access to evidence-based care. The trial is an investigator-initiated, single-centre, assessor-blinded, randomized clinical superiority trial of short-term (20 weeks) compared to long-term (14 months) outpatient mentalization-based therapy for borderline personality disorder or subthreshold borderline personality disorder. Participants will be recruited from the Outpatient Clinic for Personality Disorders at Stolpegaard Psychotherapy Centre, Mental Health Services, Capital Region of Denmark. Participants will be assessed at trial intake using the Mini International Neuropsychiatric Interview and the Structured Clinical Interview for DSM-5 Personality Disorders. Participants will be included if they meet a minimum of four DSM-5 criteria for borderline personality disorder. Participants will be assessed blind to treatment allocation at baseline, and at 8, 16, and 24 months after randomization. The primary outcome is severity of borderline symptomatology assessed using the Zanarini Rating Scale for Borderline Personality Disorder interview. Secondary outcomes include self-harm incidents, functional impairment (Work and Social Adjustment Scale), quality of life (Short-Form Health Survey), and global functioning (Global Assessment of Functioning scale). Psychiatric symptoms (Symptom Checklist 90) will be included as an exploratory outcome. Measures of personality functioning, attachment, group alliance, borderline symptoms and mentalization skills will be included as predictor and mediator variables.

mentalization-based therapy, borderline personality disorder, randomized clinical trial, psychotherapy research, treatment intensity

The experimental group is short-term mentalization-based therapy. The treatment program includes 20 weeks of mentalization-based group therapy with conjoined individual therapy every second week. The program also includes psychoeducation and individual caseformulations.

The control group is long-term mentalization-based therapy. The treatment program includes 14 months of weekly mentalization-based group therapy with combined individual therapy every second week. The program also includes psychoeducation and individual caseformulations.

Change in severity of borderline personality disorder assessed with the Zanarini Rating Scale for Borderline Personality Disorder (ZAN-BPD) interview

ZAN-BPD is an investigator-administered interview assessing change in severity of borderline personality disorder over time. Each of the nine DSM-5 criteria for borderline personality disorder are rated on a scale from 0-4, where 4 is the most severe, yielding a total score from 0-36.

WSAS is a 5-item questionnaire assessing change in functional impairment. Each item is rated on a scale from 0-8, where 0 is no impairment and 8 is severe impairment, yielding a total score between 0-40.

SF-36 is a questionnaire assessing change in self-reported quality of life over time. The instrument measures eight health dimensions: physical function (PF), role physical (RF), bodily pain (BP), social function (SF) role emotional (RE), general health (GH), vitality (VT) and mental health (MH). The questions related to each dimension are scored on a scale from 0 (worst score) to 100 (best score).

GAF is an investigator-administered rating of change in global functioning over time. Global funtioning is rated on a scale from 0-100 for both symptomatic and functional impairment, yielding two total scores from 0-100, where 100 is no impaitment and 0 is severe impairment.

Proportion of participants with severe self-harm defined as deliberate acts of self-harm resulting in visible tissue damage - data will be collected as both dichotomous data and count data.

SCL-90 is a questionnaire assessing change in psychiatric symptom distress over time. All 90 items are rated on a scale from 0-4. The total score is divided by number of items, yielding a total score on the Global Severity Index ranging from 0 to 4, where 4 is the most severe.

Inclusion Criteria exclusive to the Outpatient Clinic Age >18 years Personality disorder(s) considered to be primary diagnosis/diagnoses Inclusion Criteria exclusive to the trial: A minimum of four DSM-5 criteria for borderline personality disorder Written informed consent Exclusion Criteria exclusive to the Outpatient Clinic: Possibility of a learning disability (IQ<75) A diagnosis of schizotypal personality disorder or antisocial personality disorder Presence of a comorbid psychiatric disorder that requires specialist treatment elsewhere Current (past 2 months) substance dependance including alcohol Concurrent psychotherapeutic treatment outside the clinic Exclusion Criteria exclusive to the trial: - Lack of informed consent

Juul S, Simonsen S, Poulsen S, Lunn S, Sorensen P, Bateman A, Jakobsen JC. Detailed statistical analysis plan for the short-term versus long-term mentalisation-based therapy for outpatients with subthreshold or diagnosed borderline personality disorder randomised clinical trial (MBT-RCT). Trials. 2021 Jul 28;22(1):497. doi: 10.1186/s13063-021-05450-y.

Gibbon S, Khalifa NR, Cheung NH, Vollm BA, McCarthy L. Psychological interventions for antisocial personality disorder. Cochrane Database Syst Rev. 2020 Sep 3;9(9):CD007668. doi: 10.1002/14651858.CD007668.pub3.

Storebo OJ, Stoffers-Winterling JM, Vollm BA, Kongerslev MT, Mattivi JT, Jorgensen MS, Faltinsen E, Todorovac A, Sales CP, Callesen HE, Lieb K, Simonsen E. Psychological therapies for people with borderline personality disorder. Cochrane Database Syst Rev. 2020 May 4;5(5):CD012955. doi: 10.1002/14651858.CD012955.pub2.

Juul S, Lunn S, Poulsen S, Sorensen P, Salimi M, Jakobsen JC, Bateman A, Simonsen S. Short-term versus long-term mentalization-based therapy for outpatients with subthreshold or diagnosed borderline personality disorder: a protocol for a randomized clinical trial. Trials. 2019 Apr 5;20(1):196. doi: 10.1186/s13063-019-3306-7.