Pathways to adult substance use and abuse from childhood ADHD in the MTA



 DESCRIPTION (provided by applicant): Attention-Deficit/Hyperactivity Disorder (ADHD), one of the most common mental health conditions with origins in childhood, predicts early adulthood substance use disorders (SUDs). However, these outcomes are highly variable and often emanate from research that was not developmentally informed. Most importantly, research that seeks to explain this variability by focusing on mediators and moderators of SUD risk, beyond Conduct Disorder comorbidity and stimulant treatment, needs expansion to inform treatment and prevention. The prospective longitudinal follow-up of the children in the MTA (Multimodal Treatment of ADHD), a multi-site study that began as a randomized clinical trial of medication management, behavior therapy, and their combination for childhood ADHD Combined Subtype, provides a unique opportunity to address these concerns. The MTA sample is large (579 ADHD; 289 classmate comparison children), with good retention over 16 years into early adulthood, and it provides ample power for new and innovative tests of theory-driven hypotheses about mediators and moderators of ADHD-related risk of SUD. The narrow age range at recruitment (7-9.9) combined with longitudinal tracking improves power to test age-specific associations and developmental unfolding of contributing variables with implications for timing of interventions. The multi-site design and recruitment strategies improve generalizability of findings. Prospective data from childhood (pre- substance use) to early adulthood include comprehensive substance use measures and multiple-reporter assessments of variables pertinent to SUD risk. Data collection for the 16-year follow-up of the MTA sample, when participants were in their mid-20s, was completed in 2013 with NIDA contractual support. Funds were provided for data collection but limited support was provided for data analysis-and this support ended before adult data were available. Thus, this application seeks funding crucial to support the collaborative analytic work needed to test mechanistic developmental hypotheses, beyond simple bivariate associations tested to date, about ADHD-related onset, escalation, course, and causes of substance use and SUD into early adulthood in the MTA. We emphasize tests of theory-informed hypotheses from our recent published review that integrated literature on the etiology of drug abuse risk in typical and high risk children with the recent literature on ADHD- related impairments in adolescence and adulthood. Innovative tests of these hypotheses will have implications for understanding developmental specificity of risk processes, particularly in the transition to adulthood. Insights from the findings may identify novel treatment targets for this developmental bridge into adulthood.