Cannabis use among a nationally representative cross-sectional sample of smokers and non-smokers in the Netherlands: results from the 2015 ITC Netherlands Gold Magic Survey

Objectives Existing evidence shows that co-occurring use of tobacco and cannabis is widespread. Patterns of co-use of tobacco and cannabis may change as more jurisdictions legalise medicinal and/or recreational cannabis sales. This analysis examined predictors of current cannabis use and characterised methods of consumption among smokers and non-smokers in a context where cannabis use is legal. Setting The 2015 International Tobacco Control Netherlands-Gold Magic Survey conducted between July and August 2015. Participants Participants (n=1599; 1003 current smokers, 283 former smokers and 390 non-smokers) were asked to report their current (past 30-day) use of cigarettes and cannabis. Cigarette smokers reported whether they primarily used factory made of roll-your-own cigarettes. Those who reported any cannabis use in the last 30 days were asked about forms of cannabis used. X(2)and logistic regression analyses were used to assess relationships among combustible tobacco and cannabis use. Results Past 30-day cannabis use was somewhat higher among current tobacco (or cigarette) smokers (n=57/987=5.8%) than among former or never smokers (n=10/288=3.5% and n=6/316=1.9%, respectively). Joints were the most commonly used form of cannabis use for both current cigarette smokers (96.9%) and non-smokers (76.5%). Among those who smoked cannabis joints, 95% current smokers and 67% of non-smokers reported that they 'always' roll cannabis with tobacco. Conclusions In this Netherlands-based sample, most cannabis was reported to be consumed via smoking joints, most often mixed with tobacco. This behaviour may present unique health concerns for non-cigarette smoking cannabis users, since tobacco use could lead to nicotine dependence. Moreover, many non-cigarette smoking cannabis users appear to be misclassified as to their actual tobacco/nicotine exposure.