A brief CBT intervention for depersonalisation-derealisation disorder in psychosis: Results from a feasibility randomised controlled trial

Background and objectives: Depersonalisation/derealisation symptoms are prevalent in psychosis patients, are associated with increased impairment, and may maintain psychosis symptoms. We aimed to establish the feasibility and acceptability of a brief, six session therapy protocol adapted from a Cognitive-Behavioural model of Depersonalisation-Derealisation Disorder (DDD) in participants with psychotic symptoms. Methods: A single-blind, randomised controlled trial was conducted with a treatment-as-usual control condition. Feasibility and acceptability estimates included rates of referral, acceptance, eligibility, consent, satisfaction and improved skills/knowledge to manage depersonalisation. Results: Twenty-one individuals were recruited to the trial. Results suggest that the intervention was feasible and acceptable to participants and there is some signal of effect on clinical outcomes. Limitations: There were some challenges in recruitment. Recruitment feasibility estimates from the research register used may not be informative for future trials recruiting directly from teams. Conclusions: Overall, the results suggest that further investigations would be of interest and recommendations for this are made.