Internalizing and externalizing symptoms and suicidal behaviour in young people: a systematic review and meta-analysis of longitudinal studies.

Abstract

To assess internalizing and externalizing symptoms as risk factors for suicidal behaviour and suicide among adolescents and young adults. We conducted a systematic review of articles published until January 2017. We identified 26883 potential papers; 1701 full-text articles were assessed for eligibility, of which 1479 were excluded because of methodological reasons. Diverse meta-analyses were performed for each group of symptoms. Odds ratios (ORs) and 95% confidence intervals (95% CI) or beta coefficients for categorical variables, and effect size (ES) were calculated for continuous variables. Finally, 41 studies were included, involving participants aged 12-26years for a systematic review, and 24 articles were included for meta-analysis. The meta-analysis showed that youths with any internalizing (ES=0.93) or externalizing symptoms (ES=0.76 and OR=2.59) were more likely to attempt suicide in future. This effect was also seen in depression symptoms (OR=6.58 and ES=1.00), legal problems (OR=3.36), and anxiety (ES=0.65). Reported internalizing and externalizing symptoms are predictors of suicide behaviour in young people; therefore, the detection and management of these symptoms in young populations could be a crucial strategy for preventing suicidality in this group.