Associations between marijuana use and tobacco cessation outcomes in young adults

Abstract

Marijuana and tobacco co-use is common among young adults, and findings are mixed regarding the association between marijuana use and smoking cessation outcomes. This study examined the longitudinal relationships between marijuana use and smoking cessation outcomes among young adults (aged 18-25 years; N = 500) enrolled in a 3-month smoking cessation intervention on Facebook. At baseline and 3, 6, and 12 months, participants reported their marijuana use and their smoking behaviors (seven-day point prevalence abstinence from smoking, cigarettes per day, quit attempts) and readiness to quit. Longitudinal analyses controlled for experimental condition and adjusted for baseline stage of change, baseline average cigarettes per day, sex, alcohol use, and age participants began smoking regularly. Use of marijuana by young adult smokers was associated with a lower likelihood of reduced smoking (OR = 0.71, 95% CI [0.51, 0.98], p = .036) and a lower likelihood of abstaining from smoking (OR = 0.56, 95% CI [0.35, 0.90], p = .017) in the past seven days, as assessed over 12 months of follow-up. Use of marijuana was not significantly associated with perceptions of or engagement in the smoking cessation intervention, stage of change for quitting smoking, or tobacco quit attempts (all p's > 0.08). Study findings indicate that while marijuana use is unrelated to motivation to quit tobacco and engage in cessation interventions, marijuana use is associated with less success in reducing and abstaining from tobacco. Additional support and targeted tobacco cessation strategies to address challenges associated with marijuana co-use may be needed.

Developmental Trajectories of Tobacco/Nicotine and Cannabis Use and Patterns of Product Co-use in Young Adulthood

“… 5 For example, longitudinal studies show that more frequent cannabis use is associated with subsequent tobacco initiation, greater nicotine dependence, 6 , 7 and decreased likelihood of cigarette smoking cessation. 8 - 10 However, little is known about how different trajectories of T/C use during adolescence predict patterns of T/C use once individuals transition into young adulthood and can legally purchase these products (ie, at age 21 and above) in many parts of the United States (U.S.).…”

A systematic review and Bayesian meta‐analysis of interventions which target or assess co‐use of tobacco and cannabis in single‐ or multi‐substance interventions

“…Of these, seven indicated that they did not have the available data or were unable to provide it, four did not reply and one provided data which could not be used as the format was incompatible with other data. Thirteen authors provided data, two of whom provided data on two studies [37][38][39][40][41][42][43][44][45][46][47][48][49]. Three authors provided the original anonymized data set for our analysis and the remainder provided analyzed outcome data.…”

“…Twelve studies were RCTs [39][40][41][42][43][44][45]47,48,[60][61][62] and eight were pilot or feasibility ('uncontrolled') studies [37,38,46,49,[56][57][58][59]. Fourteen studies were from the United States, two from Switzerland, two from the United Kingdom, one from France and one from Australia.…”

“…Six studies were dual interventions targeting tobacco and cannabis [37,[56][57][58][59], seven targeted cannabis use [38,[40][41][42][43]45,49], one targeted tobacco use [47] and six targeted multi-substance use [39,44,48,61,62], including one which focused on tobacco and heavy alcohol use [44].…”

“…Cannabis use interventions consisted mainly of behavioural interventions, with only two using pharmacological treatment, one of which was an in-patient study [42,49]. The single tobacco use intervention employed behavioural components only, delivered via Facebook in both individual and group format [47]. The majority of the multisubstance interventions (MSI) were brief, with two exceptions [44,46], one of which delivered a lengthy culturally adapted intervention.…”