Depersonalisation-derealisation as a transdiagnostic treatment target: A scoping review of the evidence in anxiety, depression, and psychosis.

Depersonalisation and derealisation (DPDR) describe dissociative experiences involving distressing feelings of disconnection from oneself or one’s surroundings. The objective of this scoping review was to synthesise the evidence-base regarding DPDR as a transdiagnostic target for the treatment of anxiety, depression, and psychosis.Embase, Ovid MEDLINE, APA PsychInfo, Scopus, and PubMed were searched for empirical published research and ‘grey’ literature addressing transdiagnostic DPDR and primary anxiety, depression, or psychotic disorders. Extracted data were summarised and provided to the Lived Experience Advisory Panel for interpretation and analysis.We screened 3740 records, resulting in 42 studies addressing DPDR in the context of psychosis, 28 in anxiety, and 24 in depression.The results indicate that transdiagnostic DPDR is highly likely to be a viable treatment target in psychosis, and that it may share common cognitive processes with anxiety disorders. Evidence for the feasibility of DPDR as a treatment target in depression was sparse, and thus inconclusive.Whilst no established interventions targeting transdiagnostic DPDR were identified by this review, its findings highlight many viable options for treatment development. Given the difficulty drawing clinically meaningful conclusions from the current evidence-base, we strongly recommend that this work actively involves people with lived experience of DPDR.