Attention deficit hyperactivity disorder linked to higher
rate of young adult criminality

Children with attention deficit hyperactivity disorder (ADHD) at are heightened risk for criminality as adults, a new study shows.

Jason Fletcher and Barbara Wolfe evaluated data on nearly 14,000 individuals participating in the National Longitudinal Study of Adolescent Health (Add Health). Add Health first collected data on students when they were in grades 7 through 12, conducting follow-up interviews one year and six years later.

The study collected information from the students, parents, siblings, fellow students, and school administrators, and ADHD was identified based on participants’ retrospective reporting of symptoms during childhood. The researchers divided participants with childhood ADHD into three categories depending on whether they exhibited primarily inattention, primarily hyperactivity, or a combination.

The researchers say their data showed that participants who reported having ADHD symptoms between 5 and 12 years of age were far more likely to report participating in criminal activities as young adults than their peers without ADHD—a finding that was true for all three types of ADHD. The results remained valid when the researchers controlled for a wide range of demographic and socioeconomic factors.

Fletcher and Wolfe found that individuals with the inattentive type of ADHD were 6.5% more likely to commit a crime than their non-ADHD peers, while those with impulsive symptoms were 11% more likely and those with a combination of both inattention and hyperactivity were 5% more likely.

Individuals with the inattentive subtype of ADHD, the researchers report, had an elevated rate of all types of crimes except robbery. In particular, they committed crimes that required planning, such as selling drugs. “Individuals with impulsive symptoms had the highest increase in criminal activities of all the ADHD subtypes,” they say, “and were more likely to be arrested and convicted of a crime. The impulsive nature of their disorder seemed to lead them to engage in more impulsive crimes such as theft and robbery.”

The researchers conducted an analysis of the economic costs of ADHD-linked crime and say, “A rough estimate of this cost to victims is between 50 and 170 million dollars per year and our estimate of the total cost to society is between 2 and 4 billion dollars per year, a very sizeable cost to society.” They conclude that development of effective interventions for ADHD “could be dollars well spent in terms of crime and drug abuse averted.”