Substance use as a public health issue: A critical review of the Canadian literature, 1896-2020 (2024)

Background: The risks associated with substance use can be framed in many ways. In Canada, the consumption of psychoactive substances has at various times been considered a moral, criminal, or medical issue. In the past decade, substance use has increasingly been framed as a public health issue. This study sought to trace the historical development and evolution of the concept of a public health approach to substance use in Canada through a critical review of the academic literature.
Methods: Critical review is a method designed to systematically search a body of literature, take stock of its evolution and current state, identify conceptual contributions, and compare schools of thought. Systematic searches were conducted in February and March 2023 in five English-language databases (CINAHL, Medline, PsycInfo, Scopus, Web of Science) and three French-language databases (Cairn.info, Érudit, SDM Repère). Eligible articles were written in English or French by a first author based in Canada, focused primarily on substance use, and published in 2020 or earlier.
Results: 64 articles, published between 1896 and 2020, were synthesized. We found that while public health has been used as a framing for substance use in Canada for at least 120 years, what that means and what it implies for public policy has changed over time. During the first several decades covered in this review, we periodically see the emergence of new conceptualizations of the problem of substance use and its framing as a public health issue. For example, between the 1890s and 1980s, the dominant view of alcohol evolves from that of a social problem, to a disease, to a population health issue. In the 1990s we see the last of these paradigmatic shifts. From that point onwards, the dominant conceptualization is one that prioritizes drug policy harms over drug harms; correspondingly, proposed solutions center on harm reduction, regulation, and policy reform. Beginning in the 2000s, we see detailed proposals for a comprehensive public health framework to substance use, with authors setting out to define the premises, objectives, and components of such a framework.
Conclusion: Overall we found a gradual convergence towards a potential Canadian model for a public health approach to substance use: a model based on principles including human rights and equity, in which psychoactive substances are neither criminalized nor commercialized, but rather strictly regulated, proportionately to the risks they pose, in a manner that optimizes the health of the population. At present, governments across Canada appear to be moving in the opposite direction: drug policy is leaning further into criminalization for already illicit substances and further into commercialization for legal ones. Treating psychoactive substances as either the objects of criminal law or as harmless commodities are both associated with harm. It is incumbent on the public health sector to demonstrate that there are less harmful alternatives.