Longitudinal relationships among dissociation, paranoia, and anxiety in a clinical sample of individuals with schizophrenia-spectrum conditions

Individuals with schizophrenia endorse high levels of dissociative experiences; however, little is known about the mechanisms driving the link between psychosis and dissociative experiences. Cross-sectional research has indicated that anxiety mediates the dissociation-paranoia relationship, but longitudinal investigations of these associations remain lacking. We therefore examined how dissociation, paranoia, and anxiety-related processes relate over time in a clinical sample. Seventy-seven individuals with schizophrenia-spectrum conditions (SZ) and 72 non-clinical comparison (NCC) participants completed a 24-week longitudinal study with self-report and clinician-administered measurements of dissociation, paranoia, and anxiety. Assessments were collected at six timepoints. Dissociation was significantly elevated in SZ and was significantly associated with paranoia at every study visit. Baseline dissociation related to paranoia at four and 24 weeks. Dissociation and paranoia were significantly associated longitudinally, with both decreasing over time. While there was an overall decrease in dissociative symptomology across the study duration in SZ, certain dissociative factors (body and reality) remained stably elevated. Anxiety-related processes at four-weeks, including general anxiety, perseverative thinking, and worry, showed indirect associations with the relationship between baseline dissociation levels and paranoia at 24-weeks, consistent with a mediation model. These results highlight the importance of anomalous experiences and worry in maintaining persecutory delusions. In addition, these findings underscore altered self-experience in schizophrenia and the importance of perceptual disturbance and anxiety-related processes in sustaining paranoia over time.