Attention-deficit/hyperactivity disorder (ADHD) is a well-known risk factor for cigarette smoking, but can treatment of ADHD in adolescents decrease smoking risk? Yes, said researchers at Massachusetts General Hospital and Harvard Medical School in the online August 7 Journal of Pediatrics.

Paul Hammerness, M.D., an assistant professor of psychiatry at Harvard Medical School and the scientific coordinator of pediatric ADHD research in the Clinical and Research Program in Pediatric Psychopharmacology and Adult ADHD of Massachusetts General Hospital, and his colleagues conducted a two-year, prospective clinical trial of extended-release methylphenidate for smoking prevention in adolescents. They compared 102 adolescent ADHD subjects—about half of whom received the treatment—with 188 adolescents who did not have ADHD. The smoking rate at the end of the study was significantly lower in ADHD subjects who were receiving stimulant treatment than it was in ADHD subjects who were not, and there was no significant difference between ADHD subjects receiving stimulant treatment and non-ADHD subjects.

Subjects’ cigarette smoking was assessed by self-report using a modified version of the Fagerstrom Tolerance Questionnaire, and ADHD diagnosis was based on DSM-IV criteria.

“Although a longer-term, randomized, double-blind, placebo-controlled study would be ideal for evaluating this issue,” wrote Hammerness and colleagues, “such a study might not be feasible or ethical because it would deprive ADHD youth of effective treatment for a highly morbid disorder during a critical developmental period.”

Instead, they used an opportunistic, naturalistic sample of youth of similar age and sex with and without ADHD who received the same assessment measures.

The study drew from a previous attempt by some of the same investigators to address smoking prevention in adolescents with ADHD. That 2007 study, published in the Journal of Clinical Psychiatry, consisted of a double-blind, randomized clinical trial of the adult smoking-cessation aid bupropion in youth with ADHD who were allowed to receive concomitant open-label treatment with stimulant medication, thereby not compromising the treatment of ADHD itself. The investigators reported results that failed to support a role for bupropion in smoking prevention in the group, but suggested instead that stimulants might have such an effect.

A limitation to that study was that the effect of nonpharmacologic factors such as positive psychosocial and familial factors could not be ruled out. Hammerness and colleagues pointed out the limitations of the current study, including the inclusion of a small number of smokers at baseline rather than all smoking-naïve youth and the limited ethnic makeup of the group, but found the results to be promising.

“Although considered preliminary until replicated in future randomized clinical trials, the findings from this single-site, open-label study suggest that stimulant treatment may contribute to a decreased risk for smoking in adolescents with ADHD,” said the researchers. “If confirmed, this finding would have significant clinical and public-health impacts.”

The study was supported by Janssen Scientific Affairs as an investigator-initiated trial.

“Do Stimulants Reduce the Risk of Cigarette Smoking in Youth With Attention-Deficit/Hyperactivity Disorder? A Prospective, Long-Term, Open-Label Study of Extended-Release Methylphenidate” is posted at www.ncbi.nlm.nih.gov/pubmed/22878114.