The purpose of the PEGASUS study is to conduct a pilot trial to test the feasibility and acceptability of the PEGASUS intervention, adding a case manager and family-based interventions meetings to the existing psychiatric integrated care-models known as "Treatment Packages" in Denmark. We will conduct a randomized, assessor-blinded parallel-groups superiority clinical trial, testing the PEGASUS intervention for emotionally unstable personality disorder "EUPD", borderline type (borderline personality disorder) compared to "Treatment as Usual" before moving on to testing in a full-scale trial. Participants will be assessed at baseline and 9 month post baseline at study conclusion

Background and rationale:

Unmet needs for patients diagnosed with emotionally unstable personality disorder (borderline personality disorder).

People with emotionally unstable personality disorder, borderline type, also known as borderline personality disorder (BPD) have substantial degrees of impairment (in educational, work, family, and social functioning) even after treatment, and they contribute very substantially to the burden of psychiatric disorders on a population level. When treatment in primary care is insufficient, these patients should be referred to psychiatric integrated care-models known as "treatment packages" in the secondary psychiatric healthcare sector. The treatment packages were introduced in Denmark in 2013. More than half of patients finishing a treatment package may still have symptoms, and it is also a clinical experience and hypothesis, that many patients will continue to receive more than one treatment package either for the same disorder or for different disorders. Furthermore, the level of functioning, particularly in BPD, often remains impaired despite symptomatic relief.

Family members are often both the first and the last line of defense, as they are the people whom the patient will contact 24/7, whenever there is an obstacle or a crisis related to the mental disorder. The lives of the family members are severely affected, as they may live in constant worry for their mentally ill relative, and they may need to be ready to throw everything else aside, when there is a crisis. Moreover, they will also often play the role as self-taught lawyers or case managers to help the patient to get the necessary treatment and to avoid severe social adversities.

Enhanced treatment, case management and involvement of families Over the last 25 years we have learned a great deal about the benefits of providing additional support for people with early psychosis. Our OPUS trial resulted in more than 40 publications, and has been highly cited (2700 citations, February 2023 (Web of Science)). We have learned from the OPUS trial, that prompt and skilled treatment for those with recent onset psychosis can improve health outcomes. The most important elements in the experimental OPUS-treatment were involvement of families and affiliation with a case manager. The results of the OPUS trial have been replicated in many countries, and there is now solid evidence for "Early Intervention Services", summarized in a meta-analysis and a recent Cochrane Review. A next obvious research question is, whether the same clinical approaches and treatment elements could be helpful for other mental health conditions. In a recent Australian study it was shown, that caregivers of young people with borderline personality features experience adversities similar to, or greater than, that reported by caregivers of young people with other severe illnesses. Currently, except from a single trial carried out with young people with BPD, and few trials investigating the effect of psychoeducation or group therapy with relatives, we lack an evidence base to know, if comparable comprehensive treatment packages can help the patients with BPD and their families.

Participants

We will recruit outpatients, who have been referred to the Psychotherapeutic Outpatient Department (POD), Mental Health Centre Glostrup, Mental Health Services of the Capital Region of Denmark. The patients must have been accepted in the treatment package for BPD. The patients will be able to bring 1-2 relatives to participate in the study.

Inclusion and written consent

Patients will be approached at their first meeting, after getting accepted into the treatment package program at POD. If interested, the patients will be scheduled for an inclusion meeting with a research assistant from the project, who is a trained physician. The inclusion meeting will take place uninterrupted in an office at the POD. Here participating patients will receive detailed written and oral information about participation, and give informed written consent.

In addition to this, the patient's relatives' experience of the PEGASUS intervention and TAU will be evaluated. The relatives' contact information will be obtained through the participating patients. They will be contacted by phone to schedule an inclusion meeting. The inclusion meeting will take place by phone call, where the relatives will receive detailed information about study participation and sign a digital version of the written consent.

The participants can withdraw their consent at any time during or after the study.

Assessment

We will be collecting data at inclusion to the study and at study conclusion after 9-month treatment. An additional follow up is under consideration, but not scheduled. Assessment will be conducted by semi structured interviews, questionnaires, collecting data from patient records and register based data from the Danish registers.

Calculation of sample size and analysis

In the main trial, we will have 90% power to detect a relevant difference of 7.2 (SD 19.2) on the WHODAS, which will require 2*150=300 participants with BPD. Based on this number of participants, it will be necessary to carry out a pilot trial with 15-20 participants in each arm. We will analyze all outcomes for safety and satisfaction. As per pilot trial guidelines, we will assess nominal differences regarding safety and acceptability. Safety will be defined through potential side effects, and whether the intervention group appears to get worse over time.

Participating Patients

Inclusion Criteria:

• Must be able to give an informed written consent.
• Must be newly accepted in the pre-planned BPD treatment packages.
• ≥18 years of age.
• Agreeing to involvement of one or two informal caregivers, families, or close friends ("Relatives").
• Capable of reading and understanding Danish.

Exclusion Criteria:

• None*

  • Note that to get accepted into a treatment package for BPD, patients must not fulfill the criteria for a F20 diagnosis or the criteria for alcohol or substance abuse or harmful use.

Participating Relatives:

Inclusion Criteria:

• Must be able to give an informed written consent.
• ≥18 years of age.
• Capable of reading and understanding Danish.

Exclusion criteria: None

Available upon request.

After publication

Upon request

The investigators, outcome assessor and statistician will be blinded. Because of the nature of this study, it will not be possible to blind the participant or therapists providing the intervention.