Characterizing polysubstance use: What do we know about use of cigarettes, vaping products, cannabis, and alcohol among Canadians?

Introduction: Polysubstance use--the use of multiple substances on the same or different occasions--is a risk factor for substance use disorder. However, national surveillance of substance use in Canada has often focused on use of a single substance. To better understand and address polysubstance use, this study characterized the use of vaping products, cigarettes, inhaled cannabis, and alcohol among Canadians aged 15 years and older.

Methods: Nationally representative data from the 2020 Canadian Tobacco and Nicotine Survey were analyzed. Polysubstance use was assessed as use of at least two of the following in the past 30 days: smoking cigarettes, using vaping products (containing nicotine or flavours), using cannabis (in smoked and/or vaped form) and drinking alcohol (daily or weekly frequency).

Results: In 2020, past-30-day use of the examined substances was 4.7% for vaping products (1.5 million), 10.3% for cigarettes (3.2 million), 11.0% for inhaled cannabis (3.4 million), and 37.6% for weekly or daily use of alcohol (11.7 million). Polysubstance use was reported by 12.2% of Canadians (3.8 million) and was more prevalent among young Canadians, men and those who vaped. The most common combination of substances among polysubstance users included inhaled cannabis and weekly or daily use of alcohol (29.0%, or 1.1 million).

Conclusion: The use of vaping products, cigarettes, inhaled cannabis, and alcohol-individually and in combination-is substantial among Canadians. Frequent consumption of alcohol was most prevalent overall and, in contrast to the other examined substances, was common among Canadians of all ages. Findings may inform a polysubstance use approach for prevention policies and programs.