The Fast Track intervention's impact on behaviors of despair in adolescence and young adulthood.

How to mitigate the dramatic increase in the number of self-inflicted deaths from suicide, alcohol-related liver disease, and drug overdose among young adults has become a critical public health question. A promising area of study looks at interventions designed to address risk factors for the behaviors that precede these -often denoted-"deaths of despair." This paper examines whether a childhood intervention can have persistent positive effects by reducing adolescent and young adulthood (age 25) behaviors that precede these deaths, including suicidal ideation, suicide attempts, hazardous drinking, and opioid use. These analyses test the impact and mechanisms of action of Fast Track (FT), a comprehensive childhood intervention designed to decrease aggression and delinquency in at-risk kindergarteners. We find that random assignment to FT significantly decreases the probability of exhibiting any behavior of despair in adolescence and young adulthood. In addition, the intervention decreases the probability of suicidal ideation and hazardous drinking in adolescence and young adulthood as well as opioid use in young adulthood. Additional analyses indicate that FT's improvements to children's interpersonal (e.g., prosocial behavior, authority acceptance), intrapersonal (e.g., emotional recognition and regulation, social problem solving), and academic skills in elementary and middle school partially mediate the intervention effect on adolescent and young adult behaviors of despair and self-destruction. FT's improvements to interpersonal skills emerge as the strongest indirect pathway to reduce these harmful behaviors. This study provides evidence that childhood interventions designed to improve these skills can decrease the behaviors associated with premature mortality.