Changes in cannabis use, exposure, and health perceptions following legalization of adult recreational cannabis use in California: a prospective observational study

Kathleen Gali1, Sandra J. Winter1, Naina J. Ahuja1, Erica Frank2, Judith J. Prochaska1
1Department of Medicine, Stanford Prevention Research Center, Stanford University, Stanford, USA
2Faculty of Medicine, University of British Columbia, Vancouver, Canada

Tóm tắt

Most U.S. states have legalized cannabis for medical and/or recreational use. In a 6-month prospective observational study, we examined changes in adult cannabis use patterns and health perceptions following broadened legalization of cannabis use from medical to recreational purposes in California. Respondents were part of Stanford University’s WELL for Life registry, an online adult cohort concentrated in Northern California. Surveys were administered online in the 10 days prior to state legalization of recreational use (1/1/18) and 1-month (2/1/18–2/15/18) and 6-months (7/1/2018–7/15/18) following the change in state policy. Online surveys assessed self-reported past 30-day cannabis use, exposure to others’ cannabis use, and health perceptions of cannabis use. Logistic regression models and generalized estimating equations (GEE) examined associations between participant characteristics and cannabis use pre- to 1-month and 6-months post-legalization. The sample (N = 429, 51% female, 55% non-Hispanic White, age mean = 56 ± 14.6) voted 58% in favor of state legalization of recreational cannabis use, with 26% opposed, and 16% abstained. Cannabis use in the past 30-days significantly increased from pre-legalization (17%) to 1-month post-legalization (21%; odds ratio (OR) = 1.28, p-value (p) = .01) and stayed elevated over pre-legalization levels at 6-months post-legalization (20%; OR = 1.28, p = .01). Exposure to others’ cannabis use in the past 30 days did not change significantly over time: 41% pre-legalization, 44% 1-month post-legalization (OR = 1.18, p = .11), and 42% 6-months post-legalization (OR = 1.08, p = .61). Perceptions of health benefits of cannabis use increased from pre-legalization to 6-months post-legalization (OR = 1.19, p = .02). Younger adults, those with fewer years of education, and those reporting histories of depression were more likely to report recent cannabis use pre- and post-legalization. Other mental illness was associated with cannabis use at post-legalization only. In a multivariate GEE adjusted for sociodemographic characteristics and diagnoses, favoring legalization and the interaction of time and positive health perceptions were associated with a greater likelihood of using cannabis. Legalized recreational cannabis use was associated with greater self-reported past 30-day use post-legalization, and with more-positive health perceptions of cannabis use. Future research is needed to examine longer-term perceptions and behavioral patterns following legalization of recreational cannabis use, especially among those with mental illness.

Tài liệu tham khảo

National Conference of State Legislatures. State medical marijuana laws; 2020. http://www.ncsl.org/research/health/state-medical-marijuana-laws.aspx. Accessed 4 Nov 2020

Meng Y, Ponce N. The changing landscape: tobacco and marijuana use among young adults in California UCLA Center for health policy Reseach; 2020.

National Academies of Sciences, Engineering, and Medicine. The health effects of cannabis and cannabinoids: the current state of evidence and recommendations for research. Washington, DC: The National Academies Press; 2017. https://doi.org/10.17226/24625.

Centers for Disease Control and Prevention. Marijuana and public health; 2018. https://www.cdc.gov/marijuana/health-effects.html. Accessed 20 Nov 2019

Whiting PF, Wolff RF, Deshpande S, Di Nisio M, Duffy S, Hernandez AV, et al. Cannabinoids for medical use: a systematic review and meta-analysis. JAMA. 2015;313(24):2456–73.

Daniller A. Two-thirds of Americans support marijuana legalization; 2019. https://www.pewresearch.org/fact-tank/2019/11/14/americans-support-marijuana-legalization/. Accessed 21 Nov 2019

Substance Abuse and Mental Health Services Administration. Key substance use and mental health indicators in the United States: results from the 2019 National Survey on drug use and health. Center for Behavioral Health Statistics and Quality, Substance Abuse and Mental Health Services Administration; 2020. HHS Publication No. PEP20–07–01-001, NSDUH Series H-55

UCLA Center for Health Policy Research. Adults who have ever tried marijuana or hashish. AskCHIS 2018. http://ask.chis.ucla.edu. Accessed 11 Feb 2020.

California General Election Voter Information Guide. 2018. https://vig.cdn.sos.ca.gov/2018/general/pdf/complete-vig.pdf. Accessed 1 Jul 2019.

California Legislative Information. SB-94 cannabis: medicinal and adult use; 2017. https://leginfo.legislature.ca.gov/faces/billNavClient.xhtml?bill_id=201720180SB94. Accessed 1 Jul 2019

Corp IBM. IBM SPSS statistics for windows. Armonk: IBM Corp; 2017.

Substance Abuse and Mental Health Services Administration. Key substance use and mental health indicators in the United States: results from the 2017 National Survey on drug use and health; 2018. HHS Publication No. SMA 18–5068, NSDUH Series H-53

Vuong TD, Zhang X, Roeseler A. California tobacco facts and figures 2019. Sacramento: California Department of Public Health; 2019.

Dai H, Richter KP. A National Survey of marijuana use among US adults with medical conditions, 2016–2017. JAMA Netw Open. 2019;2(9):e1911936-e.

May P. ‘The Apple Store of Weed’: Marijuana marketing is often far from mellow. The Mercury News. 2019. May 22, 2019.

Garrick D. San Diego advances ban on marijuana billboards near schools, parks and youth centers. Los Angeles Times. 2019. October 5, 2019.

United States Census Bureau. QuickFacts California. https://www.census.gov/quickfacts/fact/table/CA/PST040219. Accessed 15 July 2020.

Statement of Vote: November 8 2016 General Election. https://elections.cdn.sos.ca.gov/sov/2016-general/sov/2016-complete-sov.pdf. Accessed 2 Apr 2020.

Twisk J, de Vente W. Attrition in longitudinal studies: how to deal with missing data. J Clin Epidemiol. 2002;55(4):329–37.