According to a study conducted at Case Western Reserve University School of Medicine, among teens with substance use disorders, those who also have social anxiety disorder begin using marijuana at a mean age of 10.6 years — an average of 2.2 years earlier than teens without anxiety.

“This finding surprised us,” said principal investigator Alexandra Wang, a third-year medical student at the university. “It shows we need to start earlier with prevention of drug and alcohol use and treatment of social phobia [in children].”

The study was consisting of 195 teens ages 14 to 18 which 102 of them or 52 percent \ were teenage girls.  They met the current diagnosis of substance use disorder and had received medical detoxification if needed.

The researchers evaluated the participants’ history of drug and alcohol use and digged into whether they’d had any of three anxiety disorders: social anxiety disorder, panic disorder, and agoraphobia.

Out of 195 teens, 92 percent had marijuana dependence and the most disturbing part was it is starting at the age of 13 years.  And on the other hand, 61 percent were alcohol-dependent, having started drinking at 13.5 years on average.  This shows that marijuana was the most popular drug of choice.

Teens with either social anxiety disorder or panic disorder were far more likely to have marijuana dependence, Wang said. Before marijuana dependence both of these disorders were more likely to occur.

More or less 80 percent of teens suffering from social anxiety disorder and 85 percent with panic disorder had symptoms of that disorder previous to the onset of their substance abuse.  In addition, panic disorder has a propensity to start before alcohol dependence and came about in 75 percent of alcohol-dependent adolescents.

According to the authors, there was no clear evidence showing whether agoraphobia came before or after either marijuana use or the first drink.

A limitation of the study, according to the research team, was that 128 (66 percent) of the teens were juvenile offenders who had received court-referred treatment for their substance abuse. These findings might not generalize to a less severely addicted population.

Yet again, interventions to lessen social anxiety might help avoid substance abuse in teens.

“We need to treat these young patients initially with non-pharmacologic means, such as cognitive behavioral therapy or mindfulness meditation,” said Christina Delos Reyes, M.D., a psychiatrist specializing in addictions at University Hospitals Case Medical Center.

Patrick Bordeaux, M.D., a child and adolescent psychiatrist in Quebec, Canada, said that “comorbidities tend to be the rule in adolescents, not the exception.”

“Adolescents are more likely to have social and mental disorders that make them more likely to use drugs,” said Bordeaux, who was not involved with the study.