Among key social determinants, connection associated with lowest odds of non-suicidal self-injury and suicidal ideation among Australian youth.

Abstract

Objective: To test the relative importance of key social determinants (as specified in the Australian National Suicide Prevention Strategy 2025-2035) associated with suicidal ideation and non-suicidal self-injury in Australian youth.

Methods: Representative data from the cross-sectional National Study of Mental Health and Wellbeing 2020-2022 were analysed for Australian youth aged 16-24 years. We used population-weighted multivariable logistic regression analyses to predict 12-month suicidal ideation and non-suicidal self-injury from several social determinants: household income, receipt of government pension/allowance payments, study/work engagement, experience of homelessness, household financial stress, urban residence and social connectedness.

Results: Social connectedness was a statistically significant predictor in both models, such that a one-unit increase reduced the odds of 12-month suicidal ideation by 52% and non-suicidal self-injury by 55%. Other significant predictors were having ever experienced homelessness, which increased the odds of suicidal ideation by 116%, while each household financial stressor (e.g. not being able to pay bills on time) increased the odds of non-suicidal self-injury by 34%. No other social determinant was statistically significant in the multivariable models.

Conclusion: Social connectedness was the only social determinant associated with lower odds of both suicidal ideation and non-suicidal self-injury in youth. Although further longitudinal studies are needed to confirm these benefits, our cross-sectional findings provide initial support for the National Suicide Prevention Strategy's emphasis on strengthening social inclusion and economic security as key prevention strategies. Our findings highlight the importance of implementing and evaluating connectedness interventions for youth as a priority next step in suicide and NSSI prevention efforts.