Pittsburgh—Childhood ADHD has been shown to increase the risk for substance use and SUD by adulthood. The question is whether stimulant medications, a first-line treatment for ADHD, decrease substance use by controlling impulsivity or might cause neurobiological and behavioral sensitization to other drugs.

A new study published in the Journal of the American Medical Association Psychiatry provided an answer, finding that children taking a prescription stimulant to manage ADHD do not have more substance use or SUDs as adolescents or young adults.

The results from the University of Pittsburgh School of Medicine could offer some reassurance to parents and clinicians who are hesitant to prescribe ADHD stimulant medications out of concern that the risk for SUDs could be heightened, the authors noted.

“Stimulants are the first-line treatment recommended for most individuals with ADHD—the drug class is an evidence-based treatment with few side effects,” stated lead author Brooke Molina, PhD, in a University of Pittsburgh press release. “Because stimulant medications are classified by the Drug Enforcement Administration as Schedule Two substances with the potential for misuse, many people fear that harmful substance use could result.”

The researchers pointed out that possible associations between stimulant treatment of ADHD and subsequent substance use “remain debated and clinically relevant.”

They employed the Multimodal Treatment Study of ADHD (MTA) to test the association of stimulant treatment of ADHD with subsequent substance use. MTA was a multisite study initiated at six sites in the United States and one in Canada as a 14-month randomized clinical trial of medication and behavior therapy for ADHD, but it transitioned to a longitudinal observational study. The participants were recruited between 1994 and 1996. Children aged 7 to 9 years with rigorously diagnosed DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, fourth edition) combined-type ADHD were repeatedly assessed until a mean age of 25 years, with analysis taking place between April 2018 and February 2023.

Stimulant treatment of ADHD was measured prospectively from baseline for 16 years (10 assessments) initially using parent reports followed by young adult reports. The study team was focused on the frequency of heavy drinking, marijuana use, daily cigarette smoking, and other substance use, which were confidentially self-reported with a standardized substance use questionnaire.

The analysis involved 579 children (mean [SD] age at baseline, 8.5 [0.8] years; 465 [80%] male). “Generalized multilevel linear models showed no evidence that current (B [SE] range, –0.62 [0.55] to 0.34 [0.47]) or prior stimulant treatment (B [SE] range, –0.06 [0.26] to 0.70 [0.37]) or their interaction (B [SE] range, –0.49 [0.70] to 0.86 [0.68]) were associated with substance use after adjusting for developmental trends in substance use and age,” the researchers explained, adding, “Marginal structural models adjusting for dynamic confounding by demographic, clinical, and familial factors revealed no evidence that more years of stimulant treatment (B [SE] range, –0.003 [0.01] to 0.04 [0.02]) or continuous, uninterrupted stimulant treatment (B [SE] range, –0.25 [0.33] to –0.03 [0.10]) were associated with adulthood substance use. Findings were the same for substance use disorder as outcome.”

ADHD is a neurobehavioral condition marked by chronic patterns of inattention, hyperactivity or impulsivity, or a combination of the three, that affects day-to-day functioning. The study was among the first to address the relationship between childhood use of prescription stimulants and later SUD by accounting for dozens of demographic, clinical, and psychosocial factors that might predispose a patient to treatment and substance use.

“Our study not only accounted for age but also used a statistical method that adjusted over time for the many characteristics that may distinguish treated from non-treated individuals,” stated study coauthor Traci Kennedy, PhD. “Considering these factors allowed us to more accurately test the relationship between stimulants and substance use.”

When considering age and other time-varying characteristics, such as household income, behavior problems, and parental support, the researchers found no evidence that prescription stimulant treatment in childhood predisposed children to developing a SUD as adolescents or young adults—or protected against it.

“We hope the results of this study will help educate providers and patients,” Dr. Molina explained. “By understanding that stimulant medication initially prescribed in childhood is not linked to harmful levels of substance use, I anticipate that parents’ and patients’ fears will be alleviated.”

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.

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