BackgroundMany patients with a non-affective psychotic disorder suffer from impairments in social functioning and social cognition. To target these impairments, mentalization-based treatment for psychotic disorder, a psychodynamic treatment rooted in attachment theory, has been developed. It is expected to improve social cognition, and thereby to improve social functioning. The treatment is further expected to increase quality of life and the awareness of having a mental disorder, and to reduce substance abuse, social stress reactivity, positive symptoms, negative, anxious and depressive symptoms.Methods/designThe study is a rater-blinded randomized controlled trial. Patients are offered 18 months of therapy and are randomly allocated to mentalization-based treatment for psychotic disorders or treatment as usual. Patients are recruited from outpatient departments of the Rivierduinen mental health institute, the Netherlands, and are aged 18 to 55 years and have been diagnosed with a non-affective psychotic disorder. Social functioning, the primary outcome variable, is measured with the social functioning scale. The administration of all tests and questionnaires takes approximately 22 hours. Mentalization-based treatment for psychotic disorders adds a total of 60 hours of group therapy and 15 hours of individual therapy to treatment as usual. No known health risks are involved in the study, though it is known that group dynamics can have adverse effects on a psychiatric disorder.DiscussionIf Mentalization-based treatment for psychotic disorders proves to be effective, it could be a useful addition to treatment.Trial registrationDutch Trial Register. NTR4747. Trial registration date 08-19-2014.

Social functioning can be severely impaired in non-affective psychotic disorder (NAPD). Current models of psychosis pathogenesis do not tend to focus on social dysfunction and pharmacological treatment fails to ameliorate it. In this article, we propose that mentalization theory provides a valuable contribution to the understanding and treatment of NAPD. Impaired mentalizing may contribute to both positive and negatives symptoms as well as social dysfunction observed in NAPD. Furthermore, impaired mentalizing may help explain the relation between childhood abuse, insecure attachment and psychosis. Mentalization based treatment may contribute to the functional recovery of NAPD patients as it targets the social cognitive processes underlying social interaction. The article includes a description of the principles of MBT in general, specific characteristics of using MBT with patients with NAPD and a clinical vignette to illustrate these principles.

Reported childhood abuse has been linked to the severity of clinical symptoms and social dysfunction in non-affective psychotic disorder. Impaired mentalizing ability may be one of the mechanisms accounting for this effect. This study examined whether impaired mentalizing mediates the effect of reported childhood abuse on positive symptoms, negative symptoms, and social dysfunction. Eighty-seven patients with non-affective psychotic disorder were examined. Reported childhood abuse was measured using the Childhood Experience of Care and Abuse interview. Additionally, the Social Functioning Scale and the Positive and Negative Syndrome Scale were used. The Hinting Task was used to measure mentalizing impairment. Reported childhood abuse was significantly related to the severity of positive and negative symptoms, not to social dysfunction. Reported childhood abuse was also related to mentalizing impairment. Mentalizing impairment was related to negative symptoms, but not to positive symptoms or social dysfunction. Mentalizing impairment accounted for 40% of the association between reported childhood abuse and negative symptoms, indicating partial mediation. A sensitivity analysis revealed that the mediating effect was only observed in those who reported fairly severe childhood abuse.