Adverse and Positive Childhood Experiences and Suicidal Ideation in US Children and Adolescents: A Systematic Review and Meta-Analysis.

Suicide is a leading cause of premature death among US youth, and suicidal thoughts can emerge before adolescence. Adverse childhood experiences (ACEs) are established risk factors for suicidal ideation, while positive childhood experiences (PCEs) and related protective factors may reduce risk, yet no prior synthesis has quantified these associations across independent US pediatric and adolescent samples using effect estimates verified against their source publications. We searched PubMed/MEDLINE, PubMed Central, Centers for Disease Control and Prevention (CDC) publication databases, and reference lists for US-based studies that enrolled children or adolescents younger than 18 years, measured ACEs (cumulative or specific) and/or PCEs or analogous protective factors, reported self-reported suicidal ideation, and published a relative effect estimate with a 95% confidence interval (CI); one report per independent sample entered each pooled analysis. Estimates were pooled with DerSimonian-Laird random-effects models, risk of bias was assessed with the Newcastle-Ottawa Scale, and funnel-plot symmetry and Egger's test were examined for the primary pool but, with fewer than 10 studies, are reported only as exploratory. Eleven reports from 10 independent US samples met the criteria. In the primary meta-analysis of four independent samples, the highest ACE-exposure category (typically three to four or more ACEs) versus no ACEs was associated with substantially higher prevalence of suicidal ideation (pooled relative estimate: 7.19; 95% CI: 5.66-9.14; I-squared = 35%). A graded dose-response was evident, with pooled estimates of 2.78 (95% CI: 2.25-3.43) for the lowest ACE category and 4.60 (95% CI: 3.79-5.58) for intermediate categories, and in two studies reporting per-unit effects, each additional ACE was associated with 60% higher odds of suicidal ideation (pooled odds ratio: 1.60; 95% CI: 1.52-1.69; I-squared = 0%). Protective associations were consistent but not pooled: each additional PCE was associated with 13% lower risk of lifetime suicidal ideation at ages 11-12 (risk ratio: 0.87; 95% CI: 0.82-0.93), and parental monitoring, school connectedness, and family communication were associated with roughly 26-59% lower prevalence of ideation. Risk of bias was moderate for nine reports and high for two. Cumulative ACE exposure thus shows a strong, graded association with suicidal ideation among US children and adolescents, and protective childhood experiences and relationships are consistently associated with lower risk; because the pooled evidence is predominantly cross-sectional and adolescent, prospective preadolescent cohorts remain a priority, and these findings support combined risk- and strengths-based screening and prevention in pediatric and school settings.