Stimulant treatment for ADHD has no effect on risk of future substance abuse

A new study finds that the use of stimulant drugs to treat children with ADHD has no effect on their future risk of substance abuse.

The report, which will appear in the American Journal of Psychiatry and has been issued online, assessed more than 100 young men 10 years after they had been diagnosed with ADHD and is the most methologically rigorous analysis of any potential relationship between stimulant treatment and drug abuse.

“Because stimulants are controlled drugs, there has been a concern that using them to treat children would promote future drug-seeking behavior,” says Joseph Biederman, MD, director of Pediatric Psychopharmacology and Adult ADHD at Massachusetts General Hospital (MGH), the study's lead author. “But our study found no evidence that prior treatment with stimulants was associated with either increased or decreased risk for subsequent drug or alcohol abuse.”

Earlier studies examining whether stimulant treatment could increase substance abuse risk have had conflicting results, but they had several limitations, the authors note. Some only looked at adolescents, although young adults are at the highest risk of substance abuse. Others did not control for conditions such as conduct disorder that are know to be associated with substance abuse or may have looked at the impact on use of only a particular substance. The current study, designed to address those shortcomings, analyzed patterns of substance use in a group of young men 10 years after their original diagnosis with ADHD.

Of the 112 study participants, who ranged in age from 16 to 27 at the time of their reassessment, 73 percent had been treated with stimulants at some time, and 22 percent were currently receiving stimulant treatment. Study participants were interviewed using standard tools for assessment of psychiatric disorders and additional questions about their use of alcohol, tobacco products and a wide variety of psychoactive drugs. Study results, controlled for the presence of conduct diagnosis in the original diagnosis, showed no relationship between whether a participant ever received stimulant treatment and the risk of future tobacco use or alcohol or other substance abuse. The age at which stimulant treatment began and how long it continued also had no effect on substance use.

Earlier studies from the MGH Psychopharmacology group had suggested that stimulant treatment might actually reduce the risk of substance abuse in ADHD patients, who are at elevated risk to begin with, but that result did not hold up in the current analysis, which included some of the same participants. The researchers note that those shorter-term studies only followed participants into adolescence and that treatment may delay rather than totally prevent future substance use, something that should be investigated in the future.

“Our current results, combined with other investigations, should help reduce the concerns that clinicians and parents may have about the use of stimulants to treat ADHD in children,” says Biederman, a professor of Psychiatry at Harvard Medical School. The current study was supported in part by grants from the National Institutes of Health, including the National Institute for Drug Abuse. Co-authors of the article are Michael Monuteaux, ScD, Thomas Spencer, MD, Timothy Wilens, MD, Heather MacPherson and Stephen Faraone, PhD, of the Research Program in Pediatric Psychopharmacology and Adult ADHD at MGH.