Cancer Epidemiol Biomarkers Prev. 2021 Aug 4:cebp.1810.2020. doi: 10.1158/1055-9965.EPI-20-1810. Online ahead of print.
BACKGROUND: Cannabis use is increasing, including among smokers, an at-risk population for cancer. Research is equivocal on whether using cannabis inhibits quitting cigarettes. The current longitudinal study investigated associations between smoking cannabis and subsequently quitting cigarettes.
METHODS: Participants were 4,535 adult cigarette smokers from a cohort enrolled in the American Cancer Society’s Cancer Prevention Study-3 in 2009-2013. Cigarette quitting was assessed on a follow-up survey in 2015-2017, an average of 3.1 years later. Rates of quitting cigarettes at follow-up were examined by retrospectively-assessed baseline cannabis smoking status (never, former, recent), and by frequency of cannabis smoking among recent cannabis smokers (low: <3 days/month; medium: 4-19 days/month; high: >20 days/month). Logistic regression models adjusted for sociodemographic factors, smoking and health-related behaviors, and time between baseline and follow-up.
RESULTS: Adjusted cigarette quitting rates at follow-up did not differ significantly by baseline cannabis smoking status [never 36.2%, 95% confidence interval (CI), 34.5%-37.8%; former 34.1%, CI, 31.4%-37.0%; recent 33.6%, CI, 30.1%-37.3%], nor by frequency of cannabis smoking (low 31.4%, CI, 25.6%-37.3%; moderate 36.7%, CI, 30.7%-42.3%; high 34.4%, CI, 28.3%-40.2%) among recent baseline cannabis smokers. In cross-sectional analyses conducted at follow-up the proportion of cigarette smokers intending to quit smoking cigarettes in the next 30 days did not differ by cannabis smoking status (p=0.83).
CONCLUSIONS: Results do not support the hypothesis that cannabis smoking inhibits quitting cigarette smoking among adults.
IMPACT: Future longitudinal research should include follow-ups of >1 year, and assess effects of intensity/frequency of cannabis use and motivation to quit on smoking cessation.
Source: ncbi 2