BOCA RATON, Fla. – New research shows that a majority of U.S. adolescents with cannabis use disorder are not completing treatment, a trend that researchers warn could have serious long-term consequences.
Researchers at Florida Atlantic University’s Charles E. Schmidt College of Medicine analyzed data from more than 40,000 adolescents between the ages of 12 and 17 who received treatment between 2018 and 2021. Only about 35% completed treatment.
The most common reasons for not finishing were dropping out, transferring to another facility or being terminated by the treatment center.
“These low rates of completion of treatment among U.S. adolescents with cannabis use disorder may portend increasing short- and long-term consequences,” said Dr. Charles H. Hennekens, co-author of the study and interim chair of population health at the Schmidt College of Medicine, in a press release.
Adolescents in dependent living arrangements completed treatment at a rate of 64.4%, compared to 35.3% for those living independently. Teens who were homeless had the lowest completion rate, at just 0.2%.
“While gender differences in treatment completion were relatively small, boys were somewhat less likely to complete treatment than girls,” said Dr. Panagiota “Yiota” Kitsantas, the study’s corresponding author and former chair of FAU’s Department of Population Health.
Teens with recent legal troubles also had lower completion rates. Just over 9% of participants had been arrested in the past 30 days, and those with recent arrests were less likely to finish treatment.
Time spent in treatment mattered too. Those who stayed four to six months were more likely to complete care (37.8%), while teens in treatment for less than one month had the lowest completion rates — only 9.3% finished compared to 33.6% who did not. Most participants received care for two to six months.
Most adolescents were referred to treatment by the judicial system (38.5%), followed by self-referrals (20.3%) and other health care providers (14.8%). The most common setting was non-intensive outpatient treatment (72.1%).
Race and ethnicity also appeared to influence outcomes. Hispanic and Native Hawaiian/Pacific Islander/Asian Pacific Islander adolescents were more likely to finish treatment, while Black and white non-Hispanic teens were less likely. Additionally, teens with co-occurring mental health or other substance use disorders were less likely to complete their programs.
“Research like this is essential because it gives us a clearer picture of who is falling through the cracks, and why,” said Dr. Lewis S. Nelson, dean and chief of health affairs at the Schmidt College of Medicine. “Adolescents are not just small adults; their brains, behaviors and environments demand approaches grounded in evidence and tailored to their unique needs.”
Nearly 60% of participants began using cannabis between ages 12 and 14, and more than one-third had co-occurring mental health and substance use disorders. Those who started using cannabis at age 11 or younger had the lowest completion rate of all — just 12.9%.
Researchers say more data-driven approaches are needed to improve access, retention and outcomes for adolescents — especially those most at risk of falling through the cracks.
