ADHD drugs reduce risk of criminal behaviour, drug abuse and accidents

People with ADHD who take drugs to manage their symptoms have a lower risk of suicidal behaviours, criminal convictions, drug abuse, being accidentally injured or being in a road accident, according to a study of 150,000 people in Sweden. Previous research has suggested this is the case, but the researchers behind the latest study say this is the most reliable evidence so far.

“This is the best approach, the closest to a randomised trial,” says Zheng Chang at the Karolinska Institute in Sweden.

When drugs are considered for managing ADHD, the wider consequences of not taking them can be overlooked, says team member Samuele Cortese at the University of Southampton in the UK. For instance, parents tend to focus on the immediate issues their children are having at school, he says, but they should also be informed about the longer-term outlook.

“If you don’t treat ADHD, there are risks,” he says. “Now we have evidence that treatment reduces these risks.”

People with ADHD often have trouble paying attention and may make impulsive decisions. Randomised controlled trials show that drugs are effective for managing these immediate symptoms.

These kinds of trials involve randomly assigning people to get a treatment or not, and they are regarded as the gold standard in medicine. But no randomised trials have looked at the wider effects of taking ADHD drugs. Instead, researchers have had to rely on observational studies, which aren’t set up to show whether taking the drugs actually cause the observed changes in symptoms or behaviour.

Now, Chang, Cortese and their colleagues have done what is known as target trial emulation, which involves analysing observational data as if it were from a randomised trial. They used data from Sweden’s medical and legal records to compare people who were put on ADHD drugs soon after diagnosis with those who didn’t start so quickly.

They found that people on ADHD medication were 25 per cent less likely to get criminal convictions or have an issue with drugs or alcohol. They were also 16 per cent less likely to be involved in a road accident, 15 per cent less likely to attempt suicide and 4 per cent less likely to have accidental injuries.

“It’s always helpful to know if medications can impact daily life beyond reducing symptoms,” Adam Guastella at the University of Sydney in Australia told the Science Media Centre in the UK. “This information is also important for governments to help policy-makers understand the potential benefits of treatment for broader society, such as mental health or criminal outcomes.”

Need a listening ear? UK Samaritans: 116123 (samaritans.org); US 988 Suicide & Crisis Lifeline: 988 (988lifeline.org). Visit bit.ly/SuicideHelplines for other countries.