Teens with attention deficit hyperactivity disorder (ADHD) or conduct disorder are at increased risk of starting to smoke or drink, a new study suggests.
The more symptoms of these disorders they have, the greater their risk.
Researchers at Cincinnati Children's Hospital analyzed data from more than 2,500 teens ages 12 to 15. They identified teens with a diagnosis of ADHD and/or conduct disorder, as well as teens with symptoms of those disorders, even if they had not been diagnosed.
Conduct disorder is characterized by behavior that is aggressive, destructive or deceitful, HealthDay reports.
The researchers report in Drug and Alcohol Dependence that 45 percent of children in the study had at least one symptom of ADHD, and almost 15 percent had at least one symptom of conduct disorder. For each additional ADHD symptom related to inattention (but not hyperactive or impulsivity), the risk that a teen would use alcohol or tobacco increased by 8 to 10 percent. Each additional symptom of conduct disorder raised the risk of tobacco use by 31 percent.
Teens with a diagnosis of both ADHD and conduct disorder had a three- to five-times increased risk of using tobacco and alcohol, and started use at a younger age, compared with teens with neither disorder. Having ADHD alone was linked with an increased likelihood of tobacco use, but not alcohol use.
"Our findings underscore the need to counsel families about the risk of substance use as [these] children approach adolescence," said study author Dr. William Brinkman. "This need is heightened among children with ADHD and/or conduct disorder diagnoses or symptoms."