Clinical Significance of Psychotic Experiences in Preadolescent Children with Non-Psychotic Mental Disorders—The Danish High Risk and Resilience Study, VIA 11

Background and Hypothesis: Psychotic experiences (PE) are associated with higher severity of other psychopathology in adults and adolescents with non-psychotic mental disorders. Knowledge on the clinical significance of PE in children with non-psychotic mental disorders, which may help improve early identification of need for treatment, is sparse. Study Design: In this cross-sectional study, preadolescent children (n = 157, mean age 12.0, SD 0.2, range 11.1-12.7 years) at familial high-risk of schizophrenia (n = 78) or bipolar disorder (n = 40) and population-based controls (n = 39) with non-psychotic Axis I mental disorders during middle childhood were assessed for PE, dimensional psychopathology, multimorbidity, global functioning, and impact of psychopathology. Study Results: Children with PE had higher scores on total (Cohen’s d 0.40, P = .02) and internalizing dimensional symptoms (Cohen’s d 0.42, P = .02) and higher rates of multimorbidity, ie, meeting criteria for more than one mental disorder (OR 2.2, P = .04), than those without PE after accounting for familial risk. Children with PE had higher rates of self-reported impact of psychopathology after accounting for number of concurrent mental disorders and familial risk (OR 2.5, P = .01). The levels of externalizing symptoms and global functioning were not significantly different in those with and without PE. Conclusions: Presence of PE marks increased severity of concurrent non-psychotic psychopathology including more self-perceived impact of psychopathology in preadolescent children with mental disorders. PE could indicate a higher need for treatment and should be routinely assessed in child and adolescent mental health services.