The study found when teens were an average of 15 years old, 35 percent of those with ADHD said they used one or more substances, compared with 20 percent of teens without a history of the disorder, Science Daily reports. Ten percent of teens with ADHD experienced significant problems from their substance abuse, compared with 3 percent of those without ADHD.
The researchers found by age 17, about 13 percent of those with ADHD experienced marijuana abuse or dependence, compared with 7 percent of those without the disorder. Daily cigarette smoking was also higher among teens with the disorder in this age group—17 percent, compared with 8 percent among teens without ADHD.
Both teens with and without ADHD had high rates of alcohol use, the study found. Teens who were treated with ADHD medication had similar substance abuse rates, compared with those who were not being treated for the disorder.
The findings appear in the Journal of the American Academy of Child and Adolescent Psychiatry.
“This study underscores the significance of the substance abuse risk for both boys and girls with childhood ADHD,” lead author Brooke Molina, PhD, of the University of Pittsburgh School of Medicine, said in a news release. “These findings also are the strongest test to date of the association between medication for ADHD and teenage substance abuse.”
Molina added, “We are working hard to understand the reasons why children with ADHD have increased risk of drug abuse. Our hypotheses, partly supported by our research and that of others, is that impulsive decision making, poor school performance, and difficulty making healthy friendships all contribute.”