Long Term Follow-up of Mentalization-Based Treatment: Exploring Variability in Outcomes, Long-term Value and Experiences 10+ Year After Receiving MBT Day Hospital or MBT Intensive Outpatient

NCT07509216 | Not Yet Recruiting

• 1 other identifier: MEC-2025-0319
• Study Type: observational
• Target: 113
• Locations: 1 country
• Sites: 2

Brief Summary

This study is a long-term follow-up study of a previous multicenter randomized controlled trial, in which n=114 participants were included. This RCT compared the effectiveness of two intensities of mentalisation-based treatment (MBT) for individuals with borderline personality disorder (BPD). The goal of this study is to learn how people who received MBT in the past for BPD are doing more than 10 years later. MBT is a type of psychotherapy that helps people understand and manage their thoughts and feelings, and supports improvements in identity and relationships, with the aim of improving daily life functioning. The main questions this study aims to answer are:

• Fill in online questionnaires about symptoms, relationships, health, and daily functioning (about 60 minutes).
• Take part in a short interview to check whether BPD symptoms are still present (about 20 minutes).
• A smaller group will be invited for a longer semi-structured qualitative interview (about 60 minutes) to talk about their personal experiences with MBT and what has impacted their life after treatment. There are no new treatments in this study. All participants completed MBT many years ago. Participation happens online or in person based on personal preference.

Conditions

Borderline Personality Disorder

Keywords

mentalisation-based treatment; health care utilization; long-term follow-up; borderline personality disorder; psychosocial functioning; recovery; patient-reported outcomes; patient experiences; mixed-methods; qualitative research; health care costs

Outcome Measures

Primary Outcomes (1)

• Change in borderline symptom severity between 3-year follow-up and long-term follow-up

  Borderline symptom severity is measured using the Personality Assessment Inventory-Borderline Features Scale (PAI-BOR). Scores range from 0 to 72, with higher scores indicating more severe borderline features. The primary estimate of interest is the change in PAI-BOR score from the 3-year follow-up assessment to the long-term follow-up assessment conducted 10-14 years after treatment start. Repeated measures collected between baseline and 3-year follow-up will be incorporated in the analyses to account for prior trajectories.

  Assessed at long-term follow-up (10-14 years after treatment start), using prior 3-year follow-up data for comparison

Secondary Outcomes (12)

• Change in general symptom severity

  Assessed at long-term follow-up (10-14 years after treatment start), using prior 3-year follow-up data for comparison

• Change in interpersonal problems

  Assessed at long-term follow-up (10-14 years after treatment start), using prior 3-year follow-up data for comparison

• Change in quality of life

  Assessed at long-term follow-up (10-14 years after treatment start), using prior 3-year follow-up data for comparison

• Change in reflective functioning

  Assessed at long-term follow-up (10-14 years after treatment start), using prior 3-year follow-up data for comparison

• Change in personality functioning (self-reported)

  Assessed at long-term follow-up (10-14 years after treatment start), using prior 3-year follow-up data for comparison

Study Arms (2)

Day-hospital mentalisation-based treatment (MBT-DH)

Participants received MBT during the original RCT. MBT is a psychodynamically oriented psychotherapy that targets problems in identity, interpersonal relationships, and emotion regulation by supporting improvements in mentalizing capacity. All participants follow an introductory MBT program (MBT-I), consisting of 12 psycho-educational group sessions. MBT-DH involved a structured day-hospital program covering five days per week, comprising daily group psychotherapy, art therapy twice per week, mentalizing cognitive group therapy, and writing therapy. Patients also received weekly individual psychotherapy and crisis planning as needed. A psychiatrist could be consulted and medication prescribed according to APA guidelines. After the intensive phase, stepped-down care was offered to support relapse prevention, further development of mentalizing capacity, and reintegration into society.

Intensive-outpatient mentalisation-based treatment (MBT-IOP)

Participants received MBT during the original RCT. MBT is a psychodynamically oriented psychotherapy that targets problems in identity, interpersonal relationships, and emotion regulation by supporting improvements in mentalizing capacity. All participants follow an introductory MBT program (MBT-I), consisting of 12 psycho-educational group sessions. In MBT-IOP the frequency of group psychotherapy is substantially lower as compared to MBT-DH comprising two group psychotherapy sessions each week, supplemented by weekly individual psychotherapy and crisis planning if required. A psychiatrist could be consulted and medication prescribed according to APA guidelines. After the intensive phase, stepped-down care was offered to support relapse prevention, further development of mentalizing capacity, and reintegration into society.

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

The study population consists of individuals who previously participated in the randomized controlled trial comparing MBT-DH with MBT-IOP for BPD in the Netherlands. Inclusion criteria were: a BPD diagnosis (SCID-II); age 18 years or older; adequate Dutch language skills; travel time to the MBT clinic of less than one hour. Exclusion criteria: autism spectrum disorder, chronic psychotic disorder or organic brain disorder that significantly interfered with mentalizing; intellectual impairment (IQ \< 80), or antisocial personality disorder with a history of severe physical violence. For this follow-up, all 113 individuals who did not decline future contact will be approached. No new age or diagnostic limits apply. This is a non-probability sample because it consists of the entire available cohort from the original RCT. Participants will initially be invited consecutively to the qualitative substudy; if response permits, purposive sampling will be used to ensure variation.

You may qualify if:

• Participation in the original randomized controlled trial of mentalization-based treatment (MBT-DH versus MBT-IOP)
• Did not decline to be contacted for future research
• Able to provide informed consent at the time of the long-term follow-up assessment

Sponsors & Collaborators

• De Viersprong: lead
• Arkin: collaborator

Study Sites (2)

Arkin - NPI

Amsterdam, 1093MB, Netherlands

Location

De Viersprong

Halsteren, 4660AA, Netherlands

Location

MeSH Terms

Conditions

Borderline Personality Disorder; Patient Acceptance of Health Care

Condition Hierarchy (Ancestors)

Personality Disorders; Mental Disorders; Treatment Adherence and Compliance; Health Behavior; Behavior

Central Study Contacts

Maaike L. Smits, Dr.

CONTACT

0031 88 7656200; maaike.smits@deviersprong.nl

Dine J. Feenstra, Dr.

CONTACT

dineke.feenstra@deviersprong.nl

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: March 27, 2026
• First Posted: April 3, 2026
• Study Start: April 2, 2026
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): June 1, 2027
• Last Updated: April 8, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

NL (2)