Researchers Solidify Link Between ADHD and Addiction

New numbers out of the University of Toronto paint a convincing picture

By Jason Langendorf

A recent study found that more than half of young adults with attention-deficit/hyperactivity disorder (ADHD) have had a substance use disorder (SUD) in their lifetime, adding to the mounting evidence of the association between addiction and mental health.

According to results of the survey from the University of Toronto, published online ahead of the upcoming print issue of the journal Alcohol and Alcoholism, young adults with ADHD were 69% more likely to have an SUD than their peers without ADHD—even after factoring for other variables that can affect predisposition to addiction. Twenty-seven percent of the survey participants with ADHD had a history of depression, as opposed to 11% among those without ADHD.

One potential explanation for the extremely high rate of illicit drug use among those with ADHD is the accelerated gateway hypothesis. This theory posits that people with ADHD tend to initiate substance use at a younger age, resulting in riskier use and greater problem severity in adulthood.”—Senyo Agbeyaka, co-author of the University of Toronto study

“These results emphasize the importance of addressing depression and anxiety when providing care to those with co-occurring ADHD and SUD,” reported lead author Esme Fuller-Thomson, a professor at University of Toronto’s Factor-Inwentash Faculty of Social Work and director of the Institute for Life Course and Aging. “Individuals with untreated depression and anxiety may self-medicate to manage the symptoms of an untreated psychiatric disorder, which can result in greater substance use.”

What Is ADHD?

The Centers for Disease Control and Prevention (CDC) defines ADHD as “one of the most common neurodevelopmental disorders of childhood. Children with ADHD may have trouble paying attention, controlling impulsive behaviors (may act without thinking about what the result will be), or be overly active.”

The study, conducted through the Canadian Community Health Survey-Mental Health, surveyed adults age 20 to 39. It was a nationally representative sample of 270 individuals with ADHD and 6,602 without ADHD. Researchers found that 36% of young adults with ADHD had a lifetime alcohol use disorder (AUD), compared to 19% for those without ADHD. Adjusting for variables, the ADHD group also was more likely to develop a cannabis use disorder and other drug use disorders than those in the control group.

ADHD
Childhood trauma can be part of the complex mix that leads to SUD.

“One potential explanation for the extremely high rate of illicit drug use among those with ADHD is the accelerated gateway hypothesis,” said co-author Senyo Agbeyaka, a recent University of Toronto MSW graduate who is a social worker at University Health Network. “This theory posits that people with ADHD tend to initiate substance use at a younger age, resulting in riskier use and greater problem severity in adulthood.”

Building on Previous Research

Previous research has suggested a link between SUD and ADHD, and also has identified the association between childhood adversity and addiction. The exact nature of these relationships is still unclear—genetics likely play a role, but many survey respondents in the Alcohol and Alcoholism study also reported childhood trauma. Those researchers emphasize that more specialized SUD programs are needed, as well as greater sensitivity to the complexities of mental health in general.

“There is a clear need to develop prevention and treatment programs to address substance use issues among those with ADHD,” said Fuller-Thomson, “while also promoting mental health and addressing childhood adversities.”

Top photo: Shutterstock; bottom photo Lucas Metz