Discussion
polysubstance, substance-related, psychosis
DISORDER
Using the LRCUG to identify higher-risk cannabis consumption behaviours, the current study used an experimental vignette design to examine how Canadian emerging adults perceived different cannabis consumption behaviours that are associated with increased risk of harm. Our results suggested that emerging adults perceived greater risks of harm associated with higher frequency of cannabis consumption, combined consumption of cannabis and tobacco, and presence of a family history of either psychosis or SUD. Further, emerging adults viewed ingesting edibles and cannabis with 5% THC and 10% CBD as associated with the least risk of harm. While effect sizes for results were small, these findings help provide some insights into emerging adults’ cannabis knowledge and familiarity with the recommendations of the LRCUG. Further, findings may help to inform public health messaging and harm reduction substance education strategies among youth and emerging adults.Encouragingly, the results of the current study suggested that emerging adults perceived almost daily consumption as having greater overall risk and potential impact on physical, cognitive, and mental health, compared to weekly consumption. However, while participants perceived daily consumption to have a greater overall risk and impact on cognitive health when compared to weekly consumption, they did not perceive any differences on the impacts to physical health and mental health. This finding is particularly concerning given that higher frequencies of consumption have been associated with an increased risk of psychosis [With respect to polysubstance use, participants perceived consuming cannabis and tobacco together as having a greater overall risk and risks to physical health compared to cannabis consumption alone. This is encouraging as emerging adults seem to appreciate that using tobacco alongside cannabis can increase the risk of harm [Notably, the only significant effect for the family history vignette was on overall risk, whereby participants perceived cannabis consumption with a family history of either psychosis or a SUD as having greater overall risk compared to cannabis consumption with no family history of mental illness or SUD. Initially, it was concerning to see no significant difference in perceptions of mental health risks between a character that had no family history of mental health or substance use concerns, compared to a family history of psychosis or SUD; however, across the three conditions, participants indicated higher ratings of risk to mental health compared to the scores of mental health risk in other vignettes. Given that the vignette conditions explicitly indicated “no family history of mental illness or substance-related issues”, “history of a substance use disorder”, or “history of a psychosis”, it seems likely that participants were primed to consider the mental health of the vignette character, ultimately impacting ratings of risk. Further, participants perceived similar levels of risk between using cannabis with a family history of psychosis or a family history of a SUD. This is a promising result as it suggests that participants viewed both as equally valid risks. In the past, cannabis was often perceived as non-addictive [Consistent with previous research, emerging adults in our study perceived smoking and vaping cannabis to be associated with greater overall risks and impacts on physical health compared to ingesting edibles. This finding suggests that emerging adults were at least partially aware of the guideline to opt for edible cannabis instead of combustible cannabis. In our sample, there were no perceived differences across any domains of risk when comparing smoking and vaping cannabis. While this is inconsistent with some existing research [In considering cannabis potency, emerging adults perceived consuming cannabis with 45% THC and 0.1% CBD as having greater overall risks and potential impacts on cognitive, physical, and mental health compared to consuming cannabis with 5% THC and 10% CBD. Similarly, emerging adults perceived consuming cannabis with 25% THC and 0.05% CBD as having greater overall risk and risks to cognitive and physical health compared to 5% THC and 10% CBD; however, they did not perceive any differences in risk to mental health. This finding suggests that emerging adults may be aware of some risks associated with a higher THC/CBD ratio or THC-dominant strains, but only partially aware of the association between increased potency and poorer mental health outcomes [