August 13, 2025

ADHD medications and risk of adverse outcomes at a population level – A target trial emulation study

While we have good Randomised Controlled Trial (RCT) data on how ADHD medications impact core symptoms, there remain gaps in our understanding of how these drugs may influence some broader clinical outcomes such as risk of suicidal behaviour, substance abuse, and accidental injury not commonly measured in RCTs. There have even been concerns that these drugs could increase these risks. We also know that ADHD is associated with non-clinical adverse events such as transport accidents and criminality, but the evidence on whether medication affects these outcomes remains limited.

This new paper, published in The BMJ, takes national register data from Sweden and uses a target trial emulation methodology to examine how ADHD medication use is associated with these outcomes. Target trial emulation is a causal inference framework using observational data to mimic the structure and protocol of an RCT, enabling researchers to address questions when an RCT may not be possible. 

Journalists came and hear from two of the authors about why they carried out this research, what a target trial emulation study is and what it can tell us about the relationship between these medications and adverse outcomes, and what the implications are at an individual and societal level.

Speakers included:

Dr Zheng Chang, Principal Researcher, Karolinska Institute

Professor Samuele Cortese, NIHR Research Professor, Professor of Child and Adolescent Psychiatry, University of Southampton, and Honorary Consultant Child and Adolescent Psychiatrist for Hampshire and Isle of Wight (HIOW) NHS Foundation Trust

This Briefing was accompanied by an SMC Roundup of comments.