M2. STRESS IS ASSOCIATED AND PREDICTS SCHIZOTYPIC AND PSYCHOTIC-LIKE EXPERIENCES IN THE FLOW OF DAILY LIFE IN NONCLINICAL AND INCIPIENT PSYCHOSIS INDIVIDUALS

BACKGROUND: Daily-life stressors, specially of a social nature, seem to play an important role in the origin and expression of the continuum of psychosis vulnerability. This study examined whether social stress and social positive appraisals in daily-life were associated, respectively, with the occurrence and the decrease of momentary psychotic-like and paranoid experiences and symptoms across the psychosis continuum. METHODS: Both social stressors and positive appraisals, as well as psychotic and paranoid experiences, were collected by means of Experience Sampling Methodology over a week. Schizotypy was assessed with the Wisconsin Schizotypy Scales. Participants were 206 nonclinical individuals oversampled for schizotypy scores (mean age=19.8) and 113 individuals with at-risk mental states for psychosis and first episode psychosis (74 and 39, respectively; mean age=22.5). RESULTS: In the nonclinical sample, appraisals of social stress (but no social contact per se) were associated with psychotic-like and paranoid experiences in daily-life, but not with diminished thoughts or emotions (negative-like symptoms). The association of stress with psychotic and paranoid experiences was moderated by positive, but not negative, schizotypy. In the clinical sample, the positive social appraisal of feeling cared for by others moderated the association between negative self-esteem and the experience of paranoia. Also, they predicted (time-lagged analyses) a decrease of these experiences at subsequent time points—although only feeling cared about did so when the previous level of paranoia was controlled for. DISCUSSION: Consistent with models postulating that stress-sensitivity is a potential mechanistic pathway of, specifically, the positive dimension of psychosis, situational and also social stress predicted psychotic-like and paranoid experiences only in participants with high positive schizotypy. Furthermore, positive social appraisals showed a critical role for buffering the expression of paranoia associated to poor self-esteem in clinical risk for and early psychosis and predicted its amelioration prospectively. Altogether, these findings support the notion that increased sensitivity to social cues is a critical aspect for both risk and resilience mechanisms in the continuum of psychosis. Additionally, they highlight the powerful relevance of positive social identification for dampening the deleterious effects of poor self-esteem and stress.