Does how you use matter? The link between mode of use and cannabis-related risk

Objectives: With the recent legalization of cannabis there are more cannabis products available to consumers today than ever before. However, little is known about the relation of distinct modes of use to cannabis-related risks. The current study estimated the prevalence of different modes of use among a sample of university students, and quantified the magnitude of association between modes of use (type and number) and cannabis-related risks (i.e., dependence, negative consequences, simultaneous use with alcohol). Methods: The sample included 368 undergraduate students (71% female) who reported using cannabis in the last 6 months. Results: Joints were the most commonly reported primary mode (39%), followed by bongs/water pipes (33%), hand pipes (14%), edibles (7%) and vaporizers (5%). The majority of participants were multi-mode users (88%). On average, participants reported using 2.72 (sd = 1.04) modes of cannabis regularly. Bong users had more cannabis related harms (B = 1.85, p <.001), dependence symptoms (B = 1.87, p <.001) and were twice as likely to use alcohol and cannabis simultaneously (OR = 2.09; 95% CI: 1.17-3.74) compared to joint users. However, these associations were attenuated after adjusting for sex, age and cannabis frequency. Multi-modal users reported significantly more cannabis-related harms and misuse symptoms compared to single mode users. Conclusion: Few differences in cannabis risks were found across modes of use. Frequency of use remains the most significant predictor of cannabis related risks. However, findings suggest that multimodal may be indicative of high risk cannabis use patterns and is an important target for screening and intervention.