Background
Suicidal thoughts and behaviours remain a leading public health concern for Australian adolescents and young adults. While research has largely focused on individual risk factors, less attention has been given to the protective role of social relationships and institutional environments during adolescence. Understanding how family, peer and school connectedness shape later suicide risk is essential for informing effective, upstream prevention strategies.
Methods
This study used longitudinal data from the Longitudinal Study of Australian Children, drawing on the nationally representative Kinder (K) cohort. Suicidal thoughts and behaviours (ideation, planning or attempts) were measured at ages 14–15, 16–17 and 18–19 years. Logistic regression models examined associations between parent–adolescent relationships, peer communication, school participation and sense of school belonging at ages 16–17 years, and suicidal thoughts and behaviours at ages 18–19 years. Analyses accounted for prior suicidal history and key sociodemographic factors.
Results
Positive family, peer and school relationships during adolescence were associated with a lower likelihood of suicidal thoughts and behaviours in emerging adulthood. A strong sense of school belonging at ages 16–17 was consistently protective at ages 18–19, regardless of prior suicidal history. Higher levels of parental trust and communication were associated with reduced risk, particularly among young people without prior suicidality. Greater peer communication and school participation were especially protective for those with a prior history of suicidal thoughts and behaviours. These factors may also act as early warning indicators when previously engaged young people become socially disengaged.
Implications
Findings reinforce evidence on the importance of family and peer relationships for suicide prevention and highlight schools as core settings for intervention. Strategies that strengthen school belonging, support parent–child communication and build positive peer relationships may reduce later suicide risk, particularly when tailored to young people with prior suicidality. Results support a systems-based, cross-portfolio approach aligned with Australia’s National Suicide Prevention Strategy.