Abstract Body

Although social anxiety disorder (SAD) is a common comorbidity in schizophrenia, there are no current guidelines on its treatment. To develop effective treatments, it was suggested that mechanisms underlying social anxiety in psychotic experiences should be investigated. This study aimed to examine which mechanisms potentially mediate social anxiety and paranoia relationship. We hypothesized that, firstly, negative social appraisals: stigma or shame; and secondly, safety behaviours: anxious avoidance or in situ defence behaviours significantly mediate social anxiety and paranoia relationship in schizophrenia.

A cross-sectional study conducted outpatients with a chronic stage of schizophrenia. Data on social anxiety, paranoia, depression, shame, stigma, anxious avoidance and in situ behaviours were collected. Mediation analysis with 10,000 bias-corrected bootstrap samples with 95%confidence intervals was used to test indirect effects of mediators.

Participants (n=113, 59.3%male) with mean age 44.2-year-old were recruited. Regarding multiple mediation analyses (co-varying for depression), stigma and shame (Hypothesis 1) did not show significant indirect effects while in situ behaviours (Hypothesis 2) showed a significant indirect effect through social anxiety-paranoia relationship.

Safety behaviours could be the key mechanism underlying relationship between social anxiety and persecutory thinking in people with established psychosis, which the in situ defence behaviours was found to be a full mediator. This study did not find negative social appraisals (shame or stigma) as a significant mediator, larger clinical study should be repeated. A greater focus on causal and mechanistic approach could produce robust findings of safety behaviours for development of targeted intervention treating SAD and paranoia in people with psychosis.