Psychotic-like experiences and multimorbid psychopathology: The relationship between the 16-item prodromal questionnaire and DSM-IV classifications in a help-seeking population.

AIM: Identifying multimorbid psychopathology is necessary to offer more adequate treatment and ultimately reduce the prevalence of persistent mental illnesses. Psychotic symptoms are increasingly seen as a transdiagnostic indicator of multimorbidity, severity and complexity of non-psychotic psychopathology. This study aims to investigate whether psychotic-like experiences and subclinical psychotic symptoms as measured by the 16-item Prodromal Questionnaire are also associated with multimorbid psychopathology. METHODS: Participants were help-seeking individuals from outpatient mental healthcare settings and intensive home-treatment teams, aged 17-35. Assessment included the 16-item Prodromal Questionnaire to measure psychotic-like experiences, the Structured Clinical Interview for DSM-IV Axis I, and three sections of the Structured Clinical Interview for DSM-IV Axis II Disorders to determine DSM-IV-TR classifications. The final sample comprised of 160 participants who scored above a cutoff of 6 items on the 16-item Prodromal Questionnaire (HIGH-score) and 60 participants who scored below cutoff (LOW-score). A Poisson Regression was executed to determine the association between the PQ-16 and DSM-IV-TR classifications. RESULTS: The HIGH-score group had a mean of 2.76 multimorbid disorders (range 0-7), while the LOW-score group had a mean of 1.45 disorders (range 0-3). Participants with four to seven disorders scored high on the 16-item Prodromal Questionnaire. CONCLUSIONS: Our results suggest that psychotic-like experiences are associated with multimorbidity and severity of psychopathology. Screening for psychotic-like experiences via the PQ-16 in a help-seeking population may help prevent under-diagnosis and under-treatment of comorbid psychopathology.

The dynamics of social activation and suspiciousness in individuals at ultra-high risk for psychosis.

INTRODUCTION: Social functioning is often impaired during the ultra-high risk (UHR) phase for psychosis, but group-level studies regarding the role of social functioning in transition to psychosis are inconsistent. Exploring the inter-individual differences which underlie the association between social functioning and psychotic symptoms in this phase could yield new insights. OBJECTIVE: To examine the idiographic and dynamic association between social activation and suspiciousness in individuals at UHR for psychosis using time-series analysis. METHODS: Twenty individuals at UHR for psychosis completed a diary application every evening for 90 days. Two items on social activation (quantity: 'time spent alone' and quality: 'feeling supported') and two items on suspiciousness ('feeling suspicious' and 'feeling disliked') were used. Time series (T = 90) of each individual were analyzed using vector auto regression analysis (VAR), to estimate the lagged (over 1 day) effect of social activation on suspiciousness, and vice versa, as well as their contemporaneous associations. RESULTS: Heterogeneous person-specific associations between social activation and suspiciousness were found in terms of strength, direction and temporal aspects. CONCLUSIONS: The association between social activation and suspiciousness differs amongst individuals who are at UHR for psychosis. These findings underline the importance of tailoring psychosocial interventions to the individual. Future studies may examine whether using results of single-subject studies in clinical practice to personalize treatment goals leads to better treatment outcomes.