PRC Resources

PRC in the News

Legalization of Medical Marijuana is Related to Use among Youth in Oregon

The legalization of marijuana for medical and recreational use has raised concerns about potential influences on marijuana use and beliefs among youth.  A recent study by the Prevention Research Center of the Pacific Institute for Research and Evaluation and the Oregon Research Institute found a higher prevalence of marijuana use among youth in Oregon counties with higher numbers of medical marijuana patients and licensed growers per 1,000 residents.

In recent years there has been a significant move toward the legalization of marijuana in the United States.  As of January 2017, it is legal for medical use in 28 states and the District of Columbia and for recreational use in eight states and the District of Columbia.  The liberalization of marijuana laws raises public health concerns, especially related to the potential effects on marijuana use by adolescents. Although adolescents rarely obtain marijuana directly from medical dispensaries, the legalization of medical marijuana may nonetheless affect adolescents’ use by increasing its availability through diversion, by fostering social norms that are favorable to marijuana use, or by reinforcing beliefs that marijuana use is not harmful.

The researchers obtained data on registered medical marijuana patients and licensed growers from 2006 to 2015 for 32 counties from the Oregon Medical Marijuana Program.  They obtained data on youth marijuana use, perceived parental disapproval, and demographic characteristics from the Oregon Healthy Teens Survey.  Across the 32 Oregon counties, the mean rate of registered medical marijuana patients per 1,000 population increased from 2.9 in 2006 to 18.3 in 2015.  The rate of licensed medical marijuana growers increased from 3.8 to 11.9.

The analysis of the data showed that the percentage of youth reporting marijuana use in the past 30 days was greater in counties with higher numbers of patients and growers per 1,000 population, when controlling for youth demographic characteristics.  In counties with a higher number of marijuana patients and growers, young people reported that their parents were less disapproving of marijuana use.  Perceptions that parents disapproved also decreased from 2006 to 2015.  These findings suggest that a greater number of registered marijuana patients and licensed growers per 1,000 population in Oregon counties was associated with a higher prevalence of marijuana use among youth from 2006 to 2015, and that this relationship was partially attributable to the youths’ perception that their parents have more favorable attitudes towards marijuana use.

The researchers concluded that youth may be more likely to use marijuana if they are exposed to more adults who use it and who do not disapprove of marijuana use.  Marijuana may also become more available through commercial and social sources after legalization for recreational use.  Lead researcher, Mallie J. Paschall stated, “We are seeing changes across the country in the legal status, availability and social attitudes towards marijuana use.  From a public health standpoint, it’s important to monitor how these changes may affect availability of marijuana and use among youth, who may suffer a number of negative consequences from use, such as car crashes and accidental injury, and effects on brain development.  We are also concerned about harm that can result from the co-use of marijuana, alcohol and other substances.”

The full paper can be found at:  Paschall, M.J., Grube, J.W., & Biglan, A. (2017) DOI: 10.1007/s10935-017-0476-5. Medical marijuana legalization and marijuana use among youth in Oregon. Journal of Primary Prevention.