O3.3. DO DEPRESSIVE SYMPTOMS MEDIATE THE RELATIONSHIPS BETWEEN SUICIDAL IDEATION AND PSYCHOTIC EXPERIENCES IN ADOLESCENTS?

Abstract Background Youth mental health is a global challenge, with onset of mental illness peaking in adolescence. In this population, depressive symptoms (DS), psychotic experiences (PE) and suicidal ideation (SI) are prevalent and risk factors for future mental disorders. DS could mediate relationships between psychotic experiences (PE) and suicidal ideation (SI); however, its precise role in this association remains uncertain. We examined whether depressive symptoms mediate the association between psychotic experiences and suicidal ideation using two complementary approaches to cross-sectional data from a community sample of adolescents. We hypothesized that DS mediate relationships between PE and SI. Additionally, we expected to find that specific DS would play a central role in this association and that this would show via higher centrality values for affective symptoms reflecting low energy, hopelessness and self-depreciating feelings in the network analyses. Methods We examined cross-sectional relationships between PE, SI and DS in a community sample of adolescents (N= 1715; 13–19 years old) recruited from Chilean secondary schools between April and August 2015. We addressed depressive symptoms (DS) using the Depression and Anxiety Scale (DASS-21). We assessed suicidal ideation using 6 items of the Columbia Suicide Severity Rating Scale (C-SSRS), adapted for being used as a self-report questionnaire. We addressed psychotic experiences (PE) by items of two pre-existing scales we adapted in prior studies with adolescents: the Community Assessment of Psychic Experiences - Positive scale (CAPE-P15), and the Brief Self-report Questionnaire for Screening Putative Pre-psychotic States (BQSPS). We first conducted a mediation analysis, where PE was the predictor, SI was the outcome, and DS were the mediator variables. Next, we performed a network analysis and estimated the strength centrality index for each symptom, and the network robustness through accuracy and stability test. Results Pearson’s correlations showed significant associations between all the variables in (SI-DS: r= .491, p