Motives and Consequences Associated with Solitary Alcohol and Cannabis Use among Co-Users during the COVID-19 Pandemic
Authors: Sadeghi Ayla , Farrelly Kyra , Wardell Jeffrey 
Published: September 2022

Background: The COVID-19 pandemic resulted in lockdowns that had an impact on alcohol and cannabis use behavior. During the height of the early lockdowns, many individuals shifted to using alcohol and cannabis in solitary contexts (e.g., Wardell et al., 2020). Solitary drinking is a non-normative behaviour that can predict severe alcohol problems and is associated with coping-motivated drinking (Keough et al. 2018; Skrzynski & Creswell, 2020). Similarly, solitary cannabis use is associated with cannabis use disorder and using cannabis to cope (Spinella et al., 2019). Further, co-use of alcohol and cannabis is related to negative consequences such as alcohol use disorder, depressive symptoms, and impaired driving (Yurasek et al., 2017). As there has been limited research on solitary alcohol and cannabis co-use, this study examined substance use motives and consequences associated with solitary use of both alcohol and cannabis among co-users during the pandemic. Methods: Canadians (N=149; 46% female; mean age = 31 years old) who reported co-use of alcohol and cannabis completed an online survey approximately 6-8 weeks into the first COVID-19 lockdown. Participants reported on past 30-day alcohol and cannabis use, solitary use, motives, and problems (i.e., Short Inventory of Problems and Marijuana Problems Scale). Participants were divided into two groups: those reporting predominantly solitary use of both alcohol and cannabis during the lockdown (solitary co-users; n=61) and those reporting predominantly social use of one or both substances during the lockdown (social co-users; n=88). Logistic regression was used to examine the unique associations of drinking motives and cannabis motives with co-use group (solitary vs. social), and to examine if the solitary co-use group was more likely to report alcohol and cannabis problems (controlling for alcohol and cannabis use). Results: Coping motives for drinking were associated with greater likelihood of being in the solitary vs. social co-use group after controlling for other drinking motives and alcohol use (OR=2.02, p=.023). Conversely, none of the cannabis use motives were significantly associated with membership in the solitary vs. social co-use group. Additionally, compared to social co-users, solitary co-users had higher odds of reporting alcohol problems, including one or more physical problems (OR=2.37, p=.033), intrapersonal problems (OR=3.95, p=.002), and social problems (OR=2.79, p=.022), after controlling for alcohol use. Cannabis-related problems did not differ between solitary and social co-users. Conclusions: Findings provide insight into the motives and consequences of solitary alcohol and cannabis use among co-users during the early stages of the COVID-19 pandemic. These findings suggest that interventions should target co-users who are using both alcohol and cannabis in a solitary context during the pandemic as they appear to be at higher risk for alcohol-related problems. Future research should examine the long-term outcomes of solitary co-use throughout the COVID-19 pandemic. Given that it is not known if the solitary co-users in this study were engaging in simultaneous use of cannabis and alcohol (i.e., using both substances on the same occasion), future ecological momentary assessment (EMA) studies should focus on understanding solitary simultaneous use during the pandemic.