Young people who display antisocial tendencies by the age of 15 are significantly more likely to develop substance use problems by the age of 17, according to new research from Sweden. In contrast, those who trust societal institutions are less likely to develop similar issues, highlighting the complex social roots of adolescent addiction. The findings were published in the journal Addictive Behaviors.
The two-year study, which followed over 3,800 teenagers from age 15–17, examined how specific social behaviours might predict later alcohol and drug use. Researchers assessed antisocial behaviours such as conduct problems and minor criminal activity, alongside prosocial traits including general kindness and trust in others and in institutions.
Findings revealed that adolescents who reported high levels of antisocial behaviours were consistently more likely to engage in all forms of substance use by age 17. This included alcohol, tobacco, snus, and illicit drugs. In particular, conduct problems emerged as the most powerful individual predictor across nearly all types of later substance use.
On the other hand, institutional trust (a form of prosocial behaviour involving confidence in bodies like government, justice systems, schools, and the media) was found to be a protective factor. Teenagers with higher institutional trust at age 15 were significantly less likely to go on to misuse substances, even when accounting for their sex, socioeconomic background, and prior substance use.
The researchers did not find the same protective effect in broader measures of kindness and general trust in people. Once adjustments were made, global prosociality and general trust no longer predicted reduced substance use, suggesting that not all prosocial traits offer equal protection.
The study also highlights how these behaviours interact. When assessed together, antisocial behaviours remained strong predictors of substance use, while institutional trust was the only prosocial trait to retain a meaningful protective influence. This suggests that conduct problems and a lack of trust in social institutions form a particularly risky combination in adolescence.
What makes these findings especially noteworthy is their relevance for prevention. If behaviours like criminal activity and defiance at 15 are linked to harmful substance use just two years later, it suggests a valuable opportunity for early intervention. Moreover, fostering institutional trust in young people – for example, through positive experiences with teachers, police, and public services – may serve as a practical prevention strategy.
While the study relied on self-reported data, which can be influenced by social desirability bias, the researchers believe their large sample size and thorough methodology provide strong evidence for the conclusions.
They also stress that the research has implications for clinical practice. In Sweden, assessments of adolescent behaviour often focus on general kindness and conduct issues, but overlook trust in institutions. These findings suggest that a more balanced assessment, one that includes how much young people trust the systems around them, could help identify those most at risk for future substance misuse.
With substance use disorders continuing to affect large numbers of young people across Europe, these findings add to growing evidence that social and behavioural factors play a crucial role in shaping health trajectories during the teenage years.
