While there were no significant demographic differences between participants with and without legal access to cannabis, those using cannabis medically were significantly older, had more education, and reported worse physical health than those using medically and recreationally. Congruent with other studies, cannabis was most commonly used for mood/stress symptoms  and chronic pain . Forty-nine percent used cannabis daily or more frequently. Two thirds had access to legal cannabis, and 48% had medical cannabis licenses. Most  participants with legal access obtained cannabis through state-licensed dispensaries. Our results highlight a troubling trend: in response to the COVID-19 pandemic, >50% of people using cannabis medically report initiation or increased use of medications/substances – most commonly alcohol. Consistent with our hypotheses, some individuals  who started using or increased medication/substance use attributed those behaviors to lack of access to cannabis products. However, despite access concerns, 35% of participants increased their cannabis use  to cope with anxiety, symptom flares, or boredom. Although our cross-sectional design precludes us from determining causality, several factors may be influencing these results. First, many people report substituting cannabis for medications and substances  due to better symptom management and fewer side effects.

As some participants were more likely to report decreased cannabis use and increased substance/medication use due to access concerns, these results may indicate that people who previously substituted cannabis could no longer do so effectively and subsequently increased/re-initiated use of other substances. If true, such changes are concerning, as cannabis substitution is often done for harm-reduction reasons and cannabis has substantially lower lethal overdose risk than other substances. Second, medical or combined medical/recreational cannabis use has been associated with worse overall health and risky health behaviors. One recent nationally representative study showed that combined medical/recreational cannabis use  was associated with higher rates of anxiety disorders compared to the general public. This finding is congruent both with our participants using cannabis for mood/stress and also increasing cannabis use typically due to anxiety. Others have shown that people using cannabis medically report high rates of prescription drug use/misuse. Similarly,vertical grow system a longitudinal cohort study of individuals with chronic pain associated cannabis use with more severe clinical pain and pain interference. As such, our data may reflect poly-substance use and/or increasing substance use to cope with medical burdens. Third, it is possible that as with other populations, people using medical cannabis are subject to stressors of COVID-19 ), resulting in coping through medications/substances. Indeed, health research firms reported increased benzodiazepine  and antidepressant  prescriptions in February and March 2020. This increase also may be because people confined to their residence are typically in closer proximity to substances than they would be otherwise, leading to greater use. Whether these effects are magnified among people using medical cannabis remains uncertain.On October 17, 2018, Bill C-45  came into force, legalizing cannabis for non-medical use across Canada. While the availability of controlled, unadulterated alternatives to black market cannabis may increase safety, cannabis use remains associated with multiple health risks, including dependence, mental health problems , and respiratory problems . Protecting and promoting public health post-legalization will require theimplementation of prevention and harm-reduction initiatives, particularly targeting at-risk groups. Indigenous Canadians, especially youth, have been identified as a population that may be at greater risk for harms associated with non-medical cannabis use . This risk may be amplified by government inaction in preparing Indigenous communities for legalization.

Concerns have been raised regarding the federal government’s lack of consultation with Indigenous communities prior to legalization, a lack of culturally appropriate public education materials, and a lack of access and funding for addiction services . Almost 5%  of Canada’s population identifies as Indigenous , a term which comprises three distinct peoples: First Nations, Métis, and Inuit. A synthesis of cannabis use patterns across this at-risk population is needed to inform the development of targeted harm reduction and prevention initiatives. However, to our knowledge, there has been no systematic review on this topic to date. Therefore, we conducted a systematic review of the literature to describe the prevalence of non-medical cannabis use among Indigenous Canadians and factors associated with non-medical cannabis use in this population.Eligible publications were published in English after January 1st, 2000 and reported primary data on the prevalence of non-medical cannabis use among one or more Canadian Indigenous peoples . There were no restrictions regarding methodology, population age, or recruitment setting. Publications were excluded if they reported only on prevalence of medical cannabis use . Reviews, commentaries, letters to the editor, and abstracts were also excluded.We systematically searched the MEDLINE, EMBASE, Web of Science, and Scopus databases from inception through January 29, 2020. The searches included Medical Subject Headings  terms and keywords  employing a combination of the following terms: Indigenous, Aboriginal, First Nation, Inuit, Métis, cannabis, marijuana, and Canada . The search was developed and implemented by an experienced health sciences librarian. In addition, the references of included publications were hand searched for potentially relevant studies that were not captured in the search and for gray literature sources. Two reviewers screened the titles and abstracts of identified publications for eligibility. Citations considered potentially eligible by either reviewer were retrieved for full-text screening and screened independently by two reviewers, with disagreements resolved by consensus or a third reviewer.Methodological, demographic, and prevalence data were extracted independently by two reviewers, with disagreements resolved by consensus or a third reviewer. Extracted data included first author, publication year, data collection year, data source, study design, recruitment strategy, location, sample characteristics, sample size, cannabis use point or period prevalence, and prevalence period used . Data on variables associated with cannabis use prevalence were extracted independently by one reviewer and verified by a second. Data were extracted for all investigated variables, regardless of the significance of their association with cannabis use or statistical tests used.

Both multivariate and bivariate data were extracted. Results pertaining to substance use in general were not extracted. Data directly comparing cannabis use prevalence in Indigenous and non-Indigenous populations were also extracted.We used a descriptive analytical approach to synthesize the prevalence of and factors associated with non-medical cannabis use among Indigenous populations in Canada. Cannabis use prevalence findings were grouped for synthesis first by age group  and then by Indigenous identity . The synthesis of factors associated with cannabis use began with a thematic analysis of variables investigated by included publications. The analysis was performed by one reviewer and verified by a second, and resulted in eleven major themes: sex, age, use of other substances, mental health, physical health, socioeconomic status , Indigenous-specific factors, school, sexual behavior, life events, and other. These themes, along with the aforementioned groups, were used to guide the reporting of associated factors. Due to substantial heterogeneity between included publications in terms of sample characteristics and years of data collection, it was not meaningful to meta analyze extracted data.Factors associated with cannabis use among adults were reported for 9 samples of on-reserve First Nations and Inuit populations. Results suggest associations between cannabis use and male sex, younger age, and use of other substances . There was also evidence of an association between cannabis use and riskier sexual behavior, higher incidence of injury, and single marital status. There was no clear association between cannabis use and physical health, mental health, or socioeconomic status , and no evidence of an association with childhood trauma. Regarding Indigenous-specific factors, there was evidence of an association between cannabis use and lower cultural involvement and intergenerational trauma; others  were not found to be associated.Factors associated with cannabis use among youth were reported for 10 samples of all Indigenous, on-reserve First Nations, and Inuit populations . Results suggest an association between cannabis use and older age, use of other substances, poorer mental health, poorer physical health, and a poorer relationship with school. There was limited evidence for an association with low SES . In addition, there was evidence for associations with Indigenous-specific factors , life events, permissive attitudes to substance use among friends, lower family connectedness and social support, poorer relationship with parents, exposure to second-hand smoke, and smaller households. Cannabis use had no association with sex.This systematic review was designed to synthesize the evidence on the prevalence of non-medical cannabis grow supplies use and factors associated with its use among Indigenous Canadians. The most recent available estimates of prevalence of use in the past year ranged from 30% among on reserve First Nations adults to 60% among Nunavik Inuit adults , and direct comparisons indicated a 1.2–15 times higher prevalence of use in Indigenous compared to non-Indigenous youth.

The available evidence indicates that the prevalence of cannabis use is higher among Indigenous Canadians than in the general population. Although no publications directly compared Indigenous and non Indigenous adults, the most recent estimate of past year cannabis use in on-reserve First Nations adults   is twice that of the general Canadian population  ; among Indigenous adults, prevalence was lowest in on-reserve First Nations compared to other groups. In adults, cannabis use was associated with male sex, whereas in youth, males and females had a similar prevalence of use. In addition, cannabis use among youth was associated with poorer mental health, poorer physical health, a poorer relationship with school, and lower neighbourhood income.Overall, our systematic review reveals that the literature on cannabis use in Indigenous Canadians is limited. Data are largely restricted to the on-reserve First Nations population, which represents around a fifth of the total Indigenous population . The paucity of data specific to off-reserve First Nations, Inuit, and Métis is an important gap in the literature, and future research is needed on cannabis use in these populations. Another notable gap in the literature is the lack of direct comparisons of cannabis use between Indigenous communities; studies have either focused on one community, or have grouped data for all participants. Future, and especially large surveys should move away from grouping data for all Indigenous populations, and towards stratification by Indigenous identity and by community/region where possible. This will enable the identification of community-specific cannabis use patterns, and is a key future research direction. Finally, the available data on cannabis use in Indigenous Canadians is largely cross-sectional, which limits in particular the interpretation of factors associated with cannabis use. Rigorous, longitudinal studies are needed. The factors associated with cannabis use identified in our systematic review are largely consistent with those previously described in the general Canadian population. Cross-Canadian surveys have indicated a higher prevalence of cannabis use among younger and male adults . Multiple publications have described an association between cannabis use and low SES among Canadian youth , and among British Columbian youth, an association was reported between cannabis use and poorer mental health, as well as use of other substances . The higher prevalence of cannabis use in Indigenous compared to non-Indigenous groups in Canada may be explained by a higher prevalence of these risk factors in the Indigenous population; the mean age of the Indigenous population is almost a decade younger than that of the general Canadian population , and lower SES  and poor youth mental health  are much more prevalent. Indigenous-specific factors such as intergenerational trauma, for which an association with cannabis use was described in both adults and youth, may also play a role. However, future research is needed to better understand the factors underlying cannabis use in this population.Canada’s cannabis legalization framework is rooted in a public health approach to cannabis regulation, which, among other objectives, involves the implementation of targeted interventions for high-risk individuals . Moving forward, there is an urgent need for culturally-appropriate interventions in the Indigenous population, particularly in youth; the protection of young Canadians was one of the principle objectives outlined in the government’s prelegalization discussion paper . Prevention interventions targeted towards Indigenous youth should be developed and implemented by or in partnership with Indigenous communities. As older youth and younger male adults are at increased risk of cannabis use, adolescence and early adulthood will be key intervention points, particularly for males. Interventions for the adult population should similarly be developed and implemented in a community engaged fashion.