Cannabis Use and Cannabis Use Disorders Among Youth in the United States, 2002-2014.

OBJECTIVE: To examine trends in past-year cannabis use (CU) and cannabis use disorders (CUD) among youth in the United States, when related changes began, and factors associated with these changes.
METHODS: This study used data from 288,300 persons aged 12-17 years who participated in the 2002-2014 National Survey on Drug Use and Health. Descriptive analyses and bivariable and multivariable logistic regressions were applied (using the year 2002 as the reference group for most analyses).
RESULTS: The prevalence of past-year CU among youth decreased from 15.8% in 2002 to 13.1% in 2014 (this downward trend occurred during 2002-2007 only [β = -0.0540, P < .0001]). Among youth cannabis users, the prevalence of past-year CUD decreased from 27.0% in 2002 to 20.4% in 2014, with a downward trend starting in 2011 (β = -0.0970, P = .0001). During 2002-2014, the prevalence of past-year tobacco use and alcohol use decreased and prevalences of past-year CU increased among tobacco users and among alcohol users. Our multivariable results suggest that declines in past-year tobacco use (but not alcohol use) among youth were associated with declines in past-year CU during 2010-2014. Past-year CU and CUD were higher among racial/ethnic minorities (except for non-Hispanic Asians and Hawaiians/Pacific Islanders for CU) than non-Hispanic whites and were similar between male and female youth during 2002-2014.
CONCLUSIONS: In the United States, compared to 2002, even after adjusting for covariates, CU decreased among youth during 2005-2014, and CUD declined among youth cannabis users during 2013-2014. Associations between declines in tobacco use and decreased CU suggest the importance of tobacco use control and prevention among youth. © Copyright 2017 Physicians Postgraduate Press, Inc.