In late October, approximately 3,700 clinicians gathered in Orlando for the 60th Annual Meeting of the American Academy of Child and Adolescent Psychiatry (AACAP) to discuss effective strategies for treating mental illness in youth.
Among those in attendance was Timothy Wilens, M.D., psychopharmacology expert and director of the Center of Addiction Medicine at Massachusetts General Hospital, who addressed issues at the intersection of attention-deficit/hyperactivity disorder (ADHD) and substance use disorders (SUDs) at the highly attended session, “Adolescent Substance Use and Psychiatric Comorbidity: Real-World Clinical Practice Essentials.”
After the session Wilens discussed with Psychiatric News his research and his theory on treating adolescents with comorbid ADHD and SUD. The following are highlights from the interview.
Q. How prevalent is ADHD and comorbid SUD diagnoses in the United States?
A. The rate of ADHD is 6 percent to 9 percent in children; and 3 percent to 4 percent in adults. If we look at the clinical samples, over half of the adults with ADHD will have a SUD. If we reverse this and began our study observing people with addiction, we will see that 25 percent of people with a substance addiction will have ADHD.
Q. Why is there such a strong association with ADHD and SUD?
A. We have been trying to search for the answer to that question. It could be three things:
Emotional deregulation associated with ADHD.
Underachievement and demoralization associated with ADHD.
It may be overlapping biological systems.
Q. Which biological systems?
A. Dopamine, a catecholamine, has been implicated in both ADHD and SUD. . . . Neurocircuitry may account for ADHD and SUD. It is not just one system that is associated [with the two disorders], and there has been literature showing that.
We investigated whether executive-function deficits [which occur in the prefrontal cortex] predicts subsequent risk for SUD in individuals with ADHD in our 2011 Journal of the American Academy of Child and Adolescent Psychiatry study. We were shocked to find out that executive-function deficit [a common symptom of ADHD] did not predict an increase in substance use outcomes, but ADHD [itself] was a predictor.
So to answer your question, we don’t know right now, but we are trying to figure it out. This is why we do research.
Q. Are individuals with comorbid ADHD and SUD more prone to abuse a particular type of drug?
A. Our data suggest that no specific drug is “preferred” and that marijuana and alcohol seem to be the most abused agents suggesting that it is the availability of these substances that is driving abuse in this group. One notable finding we had, however, is that among substance abusers, ADHD tended to abuse drugs plus alcohol more frequently than those without ADHD—suggesting a more serious form of a substance use disorder [such as] polysubstance abuse.
Q. You are known to be a big proponent of prescribing extended-release medication in children. Why do you support this practice?
A. This class of medications tends to treat the ADHD throughout the day more effectively than the shorter-acting preparation. There is less apparent “wear off and rebound” at the end of the medication cycle, and higher-risk adolescents and adults have lower abuse liability than they would with the shorter-acting preparations of stimulants.
Q. When is it appropriate to use rapid-release drugs in adolescents?
A. We tend to use them in adolescents who do not respond or cannot tolerate the extended-release preparations of medications—often because of appetite suppression or sleep issues; on weekends when adolescents may awake later and only need partial-day coverage of their ADHD symptoms; or as a supplement to extended-release preparations to provide afternoon/early evening coverage of ADHD for academic and/or extracurricular activities, including driving, work, and sports.
Q. Will treating ADHD reduce the probability of adolescents’ initiating drug use?
A. Yes. This is a tricky question. In our 2003 meta-analysis in the Journal of Child and Adolescent Psychiatry, we showed a stiff reduction and misuse of substances and alcohol [in individuals with SUD] under ADHD treatment. However, the effect associated with ADHD treatment was lost into adulthood. Most of the people stop ADHD medication. [Also,] a Swedish study followed children with untreated ADHD for substance abuse. Drug use in this study was decreased when ADHD treatment was administered.
Q. What should clinicians who treat adolescents with comorbid diagnoses for ADHD and SUD gain from your AACAP presentation and your interview with Psychiatric News?
A. Psychiatrists need to know that ADHD is a risk factor for substance abuse and that treating ADHD reduces that risk. For concurrent ADHD and SUD diagnoses, it’s best to sequence treatment—treat substance abuse first, and then go after ADHD.
Finally, physicians should be appropriately educated about the use of stimulant medications [used to treat ADHD] in order to prevent misuse by those who are at highest risk for doing so. Stimulants can be misused and diverted, so consider extended release. ■