A difference‐in‐difference approach to examining the impact of cannabis legalization on disparities in the use of cigarettes and cannabis in the United States, 2004–17. (1st February 2022)

• Record Type: Journal Article
• Authors: Weinberger, Andrea H.; Wyka, Katarzyna; Kim, June H.; Smart, Rosanna; Mangold, Michael; Schanzer, Ellen; Wu, Melody; Goodwin, Renee D.
• Is Part Of: Addiction. Volume 117:Number 6(2022)
• Page Start: 1768
• Page End: 1777
• Publication Date: 2022-02-01
• Subjects: Cannabis -- co‐use -- epidemiology -- health policy -- marijuana -- NSDUH -- smoking -- tobacco; Alcoholism -- Periodicals; Drug addiction -- Periodicals; 616.86
• DOI: 10.1111/add.15795
• Languages: English
• ISSNs: 0965-2140

Abstract

Abstract: Aims: To estimate the impact of recreational and medical cannabis laws (RCL, MCL) on the use of cannabis and cigarettes in the United States. Design: A difference‐in‐difference approach was applied to data from the 2004–17 National Survey on Drug Use and Health (NSDUH). Setting: United States. Participants: Nationally representative cross‐sectional survey of Americans aged 12 years and older (combined analytical sample for 2004–17, n = 783 663). Measurements: Data on past‐month use of (1) cigarettes and (2) cannabis were used to classify respondents into four groups: cigarette and cannabis co‐use, cigarette‐only use, cannabis‐only use or no cigarette or cannabis use. State of residence was measured by self‐report. MCL/RCL status came from state government websites. Findings: Difference‐in‐difference analyses suggest that MCL was associated with an increase in cigarette–cannabis co‐use overall [adjusted odds ratio (aOR) = 1.09; 95% confidence interval (CI) = 1.02–1.16], with the greatest increases among those aged 50 years and above (aOR = 1.60; CI = 1.39–1.84), married (aOR = 1.19; CI = 1.07–1.31), non‐Hispanic (NH) black (aOR = 1.14; CI = 1.02–1.07) and with a college degree or above (aOR = 1.15; CI = 1.06–1.24). MCL was associated with increases in cigarette‐only use among those aged 50 years and above (aOR = 1.07; CI = 1.01–1.14) and NH black (aOR = 1.16; CI = 1.06–1.27) and increases in cannabis‐only use among those aged 50 years and above (aOR = 1.24; CI = 1.07–1.44) and widowed/divorced/separated (aOR = 1.18; CI = 1.01–1.37). RCL was associated with an increase in cannabis‐only use overall (aOR = 1.21; 95% CI = 1.09–1.34), a decline in cigarette‐only use overall (aOR = 0.89; 95% CI = 0.81–0.97) and increases in co‐use among those who were married (aOR = 1.24; CI = 1.02–1.50) and aged 50 years and above (aOR = 1.37; CI = 1.03–1.84). Conclusions: Recreational and medical cannabis legalization have had a varying impact on the use, and co‐use, of cannabis and cigarettes in the United States.