Mentalisation-Based Treatment versus care-as-usual in the treatment of severe borderline personality disorders.

Objective

To examine the effectiveness/cost-effectiveness of Mentalisation-Based Treatment (MBT) for patients with severe Borderline Personality Disorders (BPD).



Design

A randomised controlled trial comparing standard psychiatric care with MBT. After a baseline measurement, patients will be followed up every 6 months for a total of 36 months.


Study populations/datasets

Patients with severe BPDs as determined with the SCID-II and a minimum score of 25 on the Borderline Personality Disorder Severity Index (BPDSI).


Intervention

The aim of MBT is to improve patients' ability to mentalise. The inability to mentalise, particularly in emotional interactions, is thought to be one of the main problems in severe borderline personality disorder. MBT is given in group sessions and individual sessions. The treatment is delivered by a multidisciplinary team in two phases of 18 months each. During the first treatment phase, patients receive intensive day treatment five days a week. In the second treatment phase, after-care treatment is provided: one individual session of psychotherapy and one group session of psychotherapy weekly.


Outcome measures

The primary clinical outcome measure is the frequency and severity of manifestations of Borderline Personality Disorder as measured with the BPDSI. Secondary outcome measures include a. number of suicide acts, b. self-mutilation, c. depression, d. subjective experiences of symptoms, e. social and interpersonal functioning, f. personality functioning, g. quality of life, h. treatment adherence.


Sample size calculation/data analysis

With two groups of 54 patients, an alpha of 0.05,an effect size of 0.9 can be detected with a statistical power of >90%. Analysis will be performed according to the intention to treat principle.


Economic evaluation

The economic evaluation will be conducted from a societal perspective with a time horizon of 36 months. Resource use and occupation-related costs will be measured using the TiC-P and PRODISQ, and will be valued using Dutch standard prices. Bootstrapping will be used to estimate the uncertainty surrounding these ratios.

Mentalisation-Based Treatment (MBT) for patients with severe Borderline Personality Disorders will result in a better clinical outcome compared with care as usual.

Baseline measurements will be taken after randomisation and follow-up measurements will be conducted 6, 12, 18, 24, 30 and 36 months after the baseline measurement.

The concept of mentalising was developed in attachment research, psychoanalytical concepts, Theory
of Mind and neurobiological research. Mentalisation can be described as the ability to understand your
own and others' mental state on the basis of overt behaviour. The inability to mentalise, particularly in
emotional interactions, is considered to be one of the main problems in borderline personality disorder,
resulting in emotional instability, impulsive behaviour, and vulnerability in interpersonal and social
interactions. MBT was developed by Peter Fonagy and Anthony Bateman (6,7,15,16) with the aim of
improving patients' ability to mentalise, specifically in situations in which this is difficult for the patient.


MBT is given in group sessions and individual sessions. The treatment comprises two phases, each
taking 18 months. During the first treatment phase, patients receive intensive partial hospitalization
treatment, five days a week. In the second phase, after-care treatment is provided, consisting of one
session of individual psychotherapy and one session of group psychotherapy weekly. This treatment is
relatively expensive and therefore it is justified to do a state of the art cost effectiveness study as
proposed in this application. In the study by Bateman and Fonagy such an extensive cost analysis was
not performed.