ADHD tied to more severe nicotine dependence

NEW YORK (Reuters Health) - Young people with attention-deficit hyperactivity disorder (ADHD) may be particularly vulnerable to serious nicotine addiction if they start smoking, a new study suggests.

Past research has shown that kids with ADHD are more likely than their peers without the disorder to start smoking. These latest findings suggest that once they do take up the habit, they also tend to become more severely nicotine-dependent, researchers report in the Journal of Pediatrics.

“The nicotine dependence appears to be about twice as bad,” said lead researcher Dr. Timothy E. Wilens of Massachusetts General Hospital in Boston.

The study, which included 166 15- to 25-year-olds with and without ADHD, found that those with the disorder scored significantly higher on a questionnaire that gauges physical dependence on nicotine.

Their average score was double that of smokers without


ADHD was not the only factor that influenced nicotine dependence, however. Young people who had a parent who smoked, friends who smoked or who lived with a smoker all tended to have more-severe nicotine addiction.

Importantly, Wilens told Reuters Health, these environmental factors all had a greater impact on study participants with ADHD. This suggests that a mix of biology and environment is at work, according to Wilens.

It’s not clear why ADHD and smoking are linked, he explained, but there is evidence that nicotine affects brain systems believed to be involved in ADHD. One study, for example, found that nicotine and the ADHD drug Ritalin each had similar effects on a protein that regulates levels of the brain chemical dopamine.

Some recent studies have also suggested that nicotine can help alleviate ADHD symptoms.

It’s possible, Wilens said, that some young people with ADHD are using cigarettes as a way to self-medicate.

The bottom line for parents of children with ADHD, he noted, is that they should discuss the importance of not smoking with their children, and make sure that their ADHD symptoms are minimized to the extent possible.

Parents should also be aware of the environmental factors that push some kids to smoke, Wilens pointed out. “If parents smoke, themselves,” he said, “they should certainly stop.”

SOURCE: Journal of Pediatrics, September 2008.