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

Andrea H Weinberger; Katarzyna Wyka; June H Kim; Rosanna Smart; Michael Mangold; Ellen Schanzer; Melody Wu; Renee D Goodwin

doi:10.1111/add.15795

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

Addiction. 2022 Jun;117(6):1768-1777. doi: 10.1111/add.15795. Epub 2022 Feb 1.

Authors

Andrea H Weinberger^{1

2}, Katarzyna Wyka³, June H Kim⁴, Rosanna Smart⁵, Michael Mangold⁶, Ellen Schanzer¹, Melody Wu^{3

7}, Renee D Goodwin^{3

7}

Affiliations

¹ Ferkauf Graduate School of Psychology, Yeshiva University, Bronx, NY, USA.
² Department of Epidemiology and Population Health, Yeshiva University Albert Einstein College of Medicine, Bronx, NY, USA.
³ Department of Epidemiology and Biostatistics, Graduate School of Public Health and Health Policy, The City University of New York, New York, NY, USA.
⁴ Institute for Implementation Science in Population Health, The City University of New York, New York, NY, USA.
⁵ Pardee RAND Graduate School, Santa Monica, CA, USA.
⁶ Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA.
⁷ Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, NY, USA.

PMID: 34985165
DOI: 10.1111/add.15795

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.

Keywords: Cannabis; NSDUH; co-use; epidemiology; health policy; marijuana; smoking; tobacco.

Publication types

Research Support, N.I.H., Extramural

MeSH terms

Analgesics
Cannabinoid Receptor Agonists
Cannabis*
Cross-Sectional Studies
Hallucinogens*
Humans
Legislation, Drug
Medical Marijuana*
Tobacco Products*
United States / epidemiology

Substances

Analgesics
Cannabinoid Receptor Agonists
Hallucinogens
Medical Marijuana

Grants and funding

R01 DA020892/DA/NIDA NIH HHS/United States