The new study also identified several risk factors that predicted who among these teens was most likely to develop substance abuse.
Researchers studied teens who became substance abusers for the first time, during four years of follow-up.
Using data from the Course and Outcome of Bipolar Youth (COBY) study, a group of researchers led by Dr. Benjamin Goldstein examined 167 kids, ages 12-17 years.
Participants in the study were interviewed an average of seven times over the course of four years in order to examine their symptoms, functioning, stressors, and treatment. Investigators then documented the frequency and possible predictors of first-onset substance abuse.
Researchers found that 32 percent of adolescents in COBY developed abuse or dependence of alcohol or drugs, on average 2.7 years from the start of the study.
Repeated experimentation with alcohol at the start of the study was the single strongest predictor of later substance abuse, although experimentation with cannabis also predicted later substance abuse.
Five other factors present at the start of the study also predicted later substance abuse: oppositional defiant disorder, panic disorder, family history of substance abuse, low family cohesiveness, and absence of antidepressant treatment.
Among teens with three or more risk factors, 54.7 percent went on to develop substance abuse, compared to 14.1 percent of teens with 0-2 risk factors.
The COBY study, funded by the National Institute of Mental Health, is the largest longitudinal study of children and adolescents with bipolar disorder.
The three-site study enrolled participants at Brown University, UCLA, and the University of Pittsburgh. COBY is continuing to follow these adolescents into their 20s and 30s.
According to Goldstein, the risk associated with experimental substance use “in the case of adolescents with bipolar disorder, even so-called recreational substance use is playing with fire.”
He concluded “we appear to have this window of two to three years during which we can attempt to prevent substance abuse in these youth. This study provides some clues regarding the types of preventive strategies that may be useful.”