Both social anxiety and psychosis exist on continua but at the same time harbour many aspects and dimensions. Whereas it is commonly accepted that social anxiety and psychosis are associated, and that both can have a negative effect on social functioning, so far insufficient attention has been paid to the complexity of these concepts and their interrelationships.
This thesis combines information from a literature review with four empirical studies to understand the connections between social anxiety, psychosis, social and occupational functioning and quality of life. A systematic review examines subtypes and dimensions of social anxiety, and relates these to psychosis concepts.
Four empirical studies place social anxiety in psychosis in a wider context. A first study compares social interaction anxiety across population samples, identifying differences in answering patterns across these samples. One study uses mediation and moderation analyses relating social anxiety and shame with perceived social exclusion as outcome. Two studies use Structural Equation Modelling (SEM) analyses to understand how social anxiety and other clinical variables and beliefs about illness relate to social defeat, which is hypothesised to predict the outcomes of social and occupational functioning and quality of life.
Systematic review: Fifty-three articles provided support for 1) discriminability of social anxiety subtypes in psychosis; 2) significant relationships between social anxiety, social anxiety subtypes, social avoidance, avoidant personality disorder or traits with certain psychosis symptoms; and 3) differences between social anxiety subtypes and avoidant personality disorder in how they relate to psychosis.
Study 1: Item Response Theory analyses identified seemingly different responses on social interaction anxiety items (SIAS) across population samples (students [N = 505]; social anxiety patients [N = 201]; patients at-risk for psychosis [N = 288]; psychosis outpatients, [N = 142]). Correlations between the parameter estimates of the samples showed that the underlying patterns in responses might be similar.
Study 2: Moderation and mediation analyses were conducted in a psychosis outpatient sample (N = 84) including social interaction anxiety (SIAS) and fear of negative evaluation (FNE), internal shame (PBIQ-R), external shame (OAS) and perceived social exclusion because of mental illness (PBIQ-R). Controlling for gender, the direct relationship between both types of social anxiety and sense of exclusion was significant, as were the mediating pathways for shame beliefs about illness. However, none of the pathways were significant when controlling for external shame. No significant moderating effect was identified for internal shame in the relationship between social anxiety and sense of exclusion.
Study 3: SEM analyses showed significant contributions to a latent social defeat variable for social interaction anxiety (SIAS), depression (BDI), “social” beliefs about illness (selected items from the PBIQ-R), and at-risk symptoms (CAARMS) in patients at risk for psychosis (N = 201). Social defeat significantly predicted social functioning (SOFAS).
Study 4: SEM analyses in a psychosis outpatient sample (N = 174) confirmed significant roles for social interaction anxiety (SIAS), social observation anxiety (SPS), depression (BDI), anxiety (BAI) and Voices (PSYRATS) in the latent variable social defeat construct, but not for Delusions (PSYRATS). Social defeat significantly predicted perceived quality of life.
The results support the complexity of the relationship of social anxiety with psychosis and showed significant contributions of social anxiety to sense of exclusion, social defeat and (indirectly) to social functioning and perceived quality of life. There may be variations in social anxiety responses across population samples, though this may not necessarily represent differences in underlying patterns. Throughout the chapters, the results are discussed in light of existing theories and evidence on social ranking and social defeat and the findings are related to current views on social anxiety in psychosis. The results of this thesis suggest a role for affect dysregulation in social outcomes in psychosis and provide future research directions.||en