Attention deficit hyperactivity disorder or ADHD, the neurodevelopmental syndrome characterized by inattention, distractibility, hyperactivity and impulsivity appears to raise the risk for substance abuse. Although typically diagnosed during childhood, ADHD persists into adolescence in 75% of cases and into adulthood in 50%. What happens to these older teens and adults and how do the symptoms of ADHD affect adult behavior and life success?

More effective and earlier interventions could be developed to prevent the development of SUD in patients already coping ADHD.

Previous studies have found that patients with ADHD have an increased likelihood of developing SUD. A recent study further explores the possible connections between the two.

Searching for Connections Between ADHD and Drug Use

The researchers wanted to see whether ADHD and substance use were in fact related, and if so, whether there were specific factors in a child’s social and medical history, in addition to ADHD, that might predict SUD in later life. The idea being that if there were additional risk factors, more effective and earlier interventions could be developed to prevent the development of SUD in patients already coping ADHD.

Subjects with ADHD were nearly one and a half times more likely to develop a substance use disorder compared with controls.

Among the possible co-factors that the researchers examined were the sex of the patient, a family history of ADHD and SUD, the presence of other psychiatric diagnoses in addition to ADHD, academic achievement and school experience, and treatment (medication and therapy) of ADHD.

The study followed two large groups of boys and girls (ages 6-17), with and without ADHD, for an average of 10 years. They monitored their substance use (drugs, alcohol, and cigarettes), and they looked at the influence of some potential additional risk factors on the onset of substance abuse.

More Likely to Try Substances Sooner, But...

The research found that people who had ADHD at the start of the study period were much more likely to develop a substance use disorder by the end of the ten year study period than were their peers who did not have ADHD.

In fact, subjects with ADHD were nearly one and a half times more likely to develop a substance use disorder compared with controls. The subjects with ADHD started smoking almost three years earlier and started using drugs about one year earlier than their peers.

What was not different between the two groups, however, was the time it took to transition from alcohol and drug use to alcohol and drug dependence. It was the same for the subjects with and those without ADHD. So while ADHD may not make one more biologically vulnerable to becoming substance-dependent, it may be the tendency toward earlier and continued use that raises that risk.
Factors to Investigate Further: Persistence and Conduct Disorder

It appears that there are a few factors behind the increased risk for development of SUDs. Subjects with persistent ADHD were about three times more likely to develop an alcohol or drug use disorder than those whose ADHD remitted during childhood. Among the group with ADHD, the subjects who also had oppositional defiant disorder and conduct disorder were also more likely to develop an SUD.

. Subjects with persistent ADHD were about three times more likely to develop an alcohol or drug use disorder than those whose ADHD remitted during childhood.

When the researchers looked at the influence of problem solving skills and school and home functioning among subjects with ADHD, they found that boys who received extra help in school or who repeated a grade were less likely to develop a SUD. However, none of the other social, family or academic factors that were assessed proved significant co-risk factors.

This study's results, published in the June issue of the Journal of the American Academy of Child and Adolescent Psychiatry, supported previous research showing that patients who were treated with medication (usually stimulants) for ADHD did not have an increased risk of developing a substance use disorder.

Medication Doesn't Raise the Risk of Substance Use Disorders

More research is needed to determine why ADHD and substance use disorders so frequently coexist. Is there a common neurobiological origin for ADHD and substance use/abuse? Do the impulsive behaviors that typify ADHD predispose one to experimenting with substances of abuse? Do the stressors inherent in coping with ADHD in academic and social settings lead to attempts at "self-medication" with drugs, alcohol or cigarettes?

The evidence that ADHD medication does not increase the risk of SUD is reassuring to patients and parents who have been concerned that the treatment of one problem might lead to another.

Children with ADHD should be screened periodically for substance use/abuse and parents and health care providers should be vigilant about early warning signs and should be diligent in educating their children about the risks of substance use. Parents who have concerns about their children should discuss them with their physicians and early interventions should be engaged if necessary.