While the legalization of marijuana for medical and recreational use has raised concerns about potential influences on marijuana use and beliefs among youth, few empirical studies have addressed this issue. We examined the association between medical marijuana patients and licensed growers per 1000 population in 32 Oregon counties from 2006 to 2015, and marijuana use among youth over the same period. We obtained data on registered medical marijuana patients and licensed growers from the Oregon Medical Marijuana Program and we obtained data on youth marijuana use, perceived parental disapproval, and demographic characteristics from the Oregon Healthy Teens Survey. Across 32 Oregon counties, the mean rate of marijuana patients per 1000 population increased from 2.9 in 2006 to 18.3 in 2015, whereas the grower rate increased from 3.8 to 11.9. Results of multi-level analyses indicated significant positive associations between rates of marijuana patients and growers per 1000 population and the prevalence of past 30-day marijuana use, controlling for youth demographic characteristics. The marijuana patient and grower rates were also inversely associated with parental disapproval of marijuana use, which decreased from 2006 to 2015 and acted as a mediator. These findings suggest that a greater number of registered marijuana patients and growers per 1000 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 perceived norms favorable towards marijuana use.
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Asbridge, M., Hayden, J. A., & Cartwright, J. L. (2012). Acute cannabis consumption and motor vehicle collision risk: Systematic review of observational studies and meta-analysis. British Medical Journal, 344, e356. Retrieved from http://www.bmj.com/content/344/bmj.e536.long.
Asbridge, M., Mann, R., Cusimano, M. D., Trayling, C., Roerecke, M., Tallon, J. M., et al. (2014). Cannabis and traffic collision risk: Findings from a case-crossover study of injured drivers presenting to emergency departments. International Journal of Public Health, 59, 395–404.
Bachman, J. G., Johnston, L. D., O’Malley, P. M., & Schulenberg, J. E. (2011). The monitoring the future project after thirty-seven years: Design and procedures. Occasional paper No. 76 (pp. 43–47). Retrieved from http://monitoringthefuture.org/pubs/occpapers/mtf-occ76.pdf.
Boyd, C. J., Veliz, P. T., & McCabe, S. E. (2015). Adolescents’ use of medical marijuana: A secondary analysis of Monitoring the Future data. Journal of Adolescent Health, 57, 241–244.
Cerdá, M., Wall, M., Keyes, K. M., Galea, S., & Hasin, D. (2012). Medical marijuana laws in 50 states: Investigating the relationship between state legalization of medical marijuana and marijuana use, abuse and dependence. Drug and Alcohol Dependence, 120, 22–27.
Chen, C.-Y., Storr, C. L., & Anthony, J. C. (2009). Early-onset drug use and risk for drug dependence problems. Addictive Behaviors, 34, 319–322.
Choo, E. K., Benz, M., Zaller, N., Warren, O., Rising, K. L., & McConnell, K. J. (2014). The impact of state medical marijuana legislation on adolescent marijuana use. Journal of Adolescent Health, 55, 160–166.
Friese, B., & Grube, J. W. (2013). Legalization of medical marijuana and marijuana use among youths. Drugs: Education Prevention and Policy, 20, 33–39.
Green, K. M., Doherty, E. E., Stuart, E. A., & Ensminger, M. E. (2010). Does heavy adolescent marijuana use lead to criminal involvement in adulthood? Evidence from a multiwave longitudinal study of urban African Americans. Drug and Alcohol Dependence, 112, 117–125.
Hall, W. (2009). The adverse health effects of cannabis use: What are they, and what are their implications for policy? International Journal of Drug Policy, 20, 458–466.
Hall, W., & Degenhardt, L. (2009). Adverse health effects of non-medical cannabis use. Lancet, 374, 1383–1391.
Hasin, D. S., Wall, M., Keyes, K. M., Cerdá, M., Schulenberg, J. E., O’Malley, P. M., et al. (2015). Medical marijuana laws and adolescent marijuana use in the USA from 1991 to 2014: Results from annual, repeated cross-sectional surveys. The Lancet Psychiatry, 2, 601–608.
Johnston, L. D., O’Malley, P. M., Miech, R. A., Bachman, J. G., & Schulenberg, J. E. (2016). Monitoring the future national survey results on drug use: 1975-2015: Overview, key findings on adolescent drug use. Ann Arbor: Institute for Social Research, The University of Michigan.
Lynne-Landsman, S. D., Livingston, M. D., & Wagenaar, A. C. (2013). Effects of state medical marijuana laws on adolescent marijuana use. American Journal of Public Health, 103, 1500–1506.
MacKinnon, D. P., & Dwyer, J. H. (1993). Estimating mediated effects in prevention studies. Evaluation Review, 17, 144–158.
National Conference of State Legislatures. (2017). State medical marijuana laws. http://www.ncsl.org/research/health/state-medical-marijuana-laws.aspx.
Oregon Health Authority. (2016). Oregon health teens survey. Documentation for OHT survey methodology was also provided by the OHA. https://public.health.oregon.gov/BirthDeathCertificates/Surveys/OregonHealthyTeens/Pages/index.aspx.
Oregon Medical Marijuana Program. (2016). The Oregon medical marijuana program: Statistical snapshot, 2016. https://public.health.oregon.gov/DiseasesConditions/ChronicDisease/MedicalMarijuanaProgram/Documents/OMMP%20Statistic%20Snapshot%20-%2001-2016.pdf.
Pacula, R. L., Powell, D., Heaton, P., & Sevigny, E. L. (2015). Assessing the effects of medical marijuana laws on marijuana use: The devil is in the details. Journal of Policy Analysis and Management, 34, 7–31.
Portland State University College of Urban and Public Affairs, Population Research Center. (2016). Annual Population Estimates. https://www.pdx.edu/prc/population-reports-estimates.
Raudenbush, S., Bryk, A., Cheong, Y. F., Congdon, R., & du Toit, M. (2011). HLM 7: Hierarchical linear and nonlinear modeling. Lincolnwood, IL: Scientific Software International.
Schuermeyer, J., Salomonsen-Sautel, S., Price, R. K., Balan, S., Thurstone, C., Min, S. J., et al. (2014). Temporal trends in marijuana attitudes, availability and use in Colorado compared to non-medical marijuana states: 2003–2011. Drug and Alcohol Dependence, 140, 145–155.
Stolzenberg, L., D’Alessio, S. J., & Dariano, D. (2016). The effect of medical cannabis laws on juvenile cannabis use. International Journal of Drug Policy, 27, 82–88.
Volkow, N. D., Swanson, J. M., Evinsm, A. E., DeLisi, L. E., Meier, M. H., Gonzalez, R., et al. (2016). Effects of cannabis use on human behavior, including cognition, motivation, and psychosis: A review. JAMA Psychiatry, 73, 292–297.
Wall, M. M., Mauro, C., Hasin, D. S., Keyes, K. M., Cerdá, M., Martins, S. S., & Feng, T. (2016). Prevalence of marijuana use does not differentially increase among youth after states pass medical marijuana laws: Commentary on and reanalysis of US National Survey on Drug Use in Households data 2002–2011. International Journal of Drug policy. doi: 10.1016/j.drugpo.2016.01.015.
Wall, M., Poh, E., Cerdá, M., Keyes, K. M., Galea, S., & Hasin, D. S. (2011). Adolescent marijuana use from 2002 to 2008: Higher in states with medical marijuana laws, cause still unclear. Annals of Epidemiology, 21, 714–716.
Wen, H., Hockenberry, J. M., & Cummings, J. R. (2015). The effect of medical marijuana laws on adolescent and adult use of marijuana, alcohol, and other substances. Journal of Health Economics, 42, 64–80.
Williams, J., & Bretteville-Jensen, A. L. (2014). Does liberalizing cannabis laws increase cannabis use? Journal of Health Economics, 36, 20–32.
This research and preparation of this paper were supported by a grant from the National Institute on Alcohol Abuse and Alcoholism (R01AA021726). The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIAAA or the National Institutes of Health. We would like to thank Emma and Zachary Adler for assisting with the acquisition and compilation of medical marijuana patient and grower data from the Oregon Medical Marijuana Program.
Conflict of Interest
The authors declare they have no conflicts of interest.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards
Informed consent was obtained from all individual participants included in the study
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Paschall, M.J., Grube, J.W. & Biglan, A. Medical Marijuana Legalization and Marijuana Use Among Youth in Oregon. J Primary Prevent 38, 329–341 (2017). https://doi.org/10.1007/s10935-017-0476-5