Self-reported psychosis-like experiences in patients with mood disorders.

Background: Self-reported psychosis-like experiences (PEs) may be common in patients with mood disorders, but their clinical correlates are not well known. We investigated their prevalence and relationships with self-reported symptoms of depression, mania, anxiety, borderline (BPD) and schizotypal (SPD) personality disorders among psychiatric patients with mood disorders.

Methods: The Community Assessment of Psychic Experiences (CAPE-42), Mood Disorder Questionnaire (MDQ), McLean Screening Instrument (MSI), The Beck Depressive Inventory (BDI), Overall Anxiety Severity and Impairment Scale (OASIS) and Schizotypal Personality Questionnaire-Brief form (SPQ-B) were filled in by patients with mood disorders (n=282) from specialized care. Correlation coefficients between total scores and individual items of CAPE-42 and BDI, SPQ-B, MSI and MDQ were estimated. Hierarchical multivariate regression analysis was conducted to examine factors influencing the frequency of self-reported PE.

Results: PEs are common in patients with mood disorders. The "frequency of positive symptoms" score of CAPE-42 correlated strongly with total score of SPQ-B (rho=0.63; P<0.001) and moderately with total scores of BDI, MDQ, OASIS and MSI (rho varied from 0.37 to 0.56; P<0.001). Individual items of CAPE-42 correlated moderately with specific items of BDI, MDQ, SPQ-B and MSI (r varied from 0.2 to 0.5; P<0.001). Symptoms of anxiety, mania or hypomania and BPD were significant predictors of the "frequency of positive symptoms" score of CAPE-42.

Conclusions: Several, state- and trait-related factors may underlie self-reported PEs among mood disorder patients. These include cognitive-perceptual distortions of SPD; distrustfulness, identity disturbance, dissociative and affective symptoms of BPD; and cognitive biases related to depressive or manic symptoms.