ADHD Linked to Later Substance Abuse
Study Shows Severity and Duration of Symptoms to Be Major Risk Factors
Aug. 18, 2003 -- Children with attention deficit hyperactivity disorder (ADHD) -- especially those with severe symptoms -- are more likely to smoke and abuse drugs and alcohol as teens, a new study shows.
Overall, the risk is similar to that of a child of an alcoholic, which is considered strongly predictive of later substance abuse, researcher Brooke Molina, PhD, tells WebMD. In the University of Pittsburgh study, those with the most severe and lasting attention problems during childhood were most likely to smoke, drink alcohol, and take drugs as teenagers.
"It is important to stress that having ADHD is in no way a guarantee that a child will become an alcoholic or drug abuser, in the same way that not all children of alcoholics have problems with alcohol," Molina tells WebMD. "But it is important that we recognize and understand the risks."
Molina and colleagues interviewed parents and teachers to determine substance abuse among 142 teenagers who had been diagnosed with ADHD as children and compared them with 100 teens with no history of ADHD. Because the ADHD kids had been followed from childhood, the researchers were able to evaluate whether the severity of individual symptoms was predictive of later smoking and drug and alcohol abuse.
Childhood ADHD was linked to earlier first use of cigarettes and progression to daily smoking and earlier use of illicit drugs. It was also associated with heavier use of alcohol and drugs. The findings are reported in the August issue of the Journal of Abnormal Psychology.
Attention problems, hyperactivity, and problems controlling impulses are all classic symptoms of ADHD. Children with the disorder often exhibit one symptom over another.
Researchers found that children with more severe attention problems were more likely to become substance abusers than children with hyperactivity and impulse control as their defining symptoms. But the severity of symptoms and the persistence of ADHD into adolescence were the most important predictors of future smoking and alcohol and drug abuse.
"The more symptoms the children had, the more at risk they were for substance abuse later on," says Molina. The researchers are now following more than 350 ADHD children to determine whether this risk of substance abuse follows them into adulthood.
Portland, Ore., child psychologist Fred Grossman remains unconvinced that ADHD is a risk factor for substance abuse. He says the studies have been inconclusive, and even those suggesting a link cannot prove a causal relationship.
Some suggest that drugs used to treat ADHD -- such as the stimulant Ritalin -- may increase the likelihood of substance abuse down the road. But recent studies from both the American Academy of Pediatrics and the American Academy of Child and Adolescent Psychiatry (AACAP) have failed to find such an association. But another study from the AACAP showed that certain behaviors linked to ADHD, such as aggression, might increase the risk of early drug use.
"There are many other factors that could be involved in future behavior that are not easily controlled for in these studies," Grossman tells WebMD. "And the water is further muddied by the fact that diagnosing attention deficit disorder is still difficult and it is widely over-diagnosed. I don't think that any one study could isolate ADHD as a causal factor [for later substance abuse]."