Daily Relations Among Alcohol and Cannabis Co-Use, Simultaneous Use, and Negative Consequences: A Day-Level Latent Profile Analysis

Abstract

Objective: Concurrent and simultaneous cannabis and alcohol co-use confers risk for daily negative alcohol consequences. However, studies often treat co-use as a dichotomy, precluding examination of higher- and lower-risk co-use days. Additionally, little is known about specific alcohol consequences associated with daily co-use. Therefore, the current study 1) differentiated days based upon alcohol consumption, co-use, and simultaneous use, and 2) tested whether certain day-level use patterns conferred risk for daily alcohol consequences. Methods: College student co-users (N=489) completed an online Timeline Followback, reporting daily alcohol consumption, negative alcohol consequences, concurrent cannabis and alcohol co-use, and simultaneous co-use (SAM) on drinking days over the past month. Day-Level Latent Profile Analysis differentiated days based upon drinking quantity, co-use, and simultaneous use, and tested whether patterns of use conferred risk for overall and specific negative alcohol consequences. Results: Four day-level profiles emerged, including moderate consumption of alcohol-only days (57.5%), moderate consumption SAM use days (29.1%), higher consumption alcohol-only days (7.4%), and higher consumption SAM use days (6%). Higher consumption SAM use days were associated with more negative alcohol consequences than all other days; however, higher consumption SAM use days differed from higher consumption alcohol-only days in acute dependence symptoms. Higher consumption alcohol-only days were associated with more negative alcohol consequences than moderate consumption SAM days, particularly those that were action-oriented (i.e., dependence symptoms, blackout drinking, impaired control, risky behavior, social/interpersonal consequences). Conclusions: Findings suggest that there are in fact lower-risk co-use days, and that links with unique negative alcohol consequences depend on levels of alcohol consumption and co-use.

Interactive effects of alcohol and cannabis quantities in the prediction of same‐day negative consequences among young adults

“…Although informative, this precludes examination of the impact that the quantities of alcohol and cannabis that are consumed have on the consequences associated with simultaneous use. Indeed, the few day-level studies that have distinguished among simultaneous use days that involve light versus heavy drinking have found that simultaneous use does not always confer greater risk for acute harms than alcohol use alone, as this may depend on the level of alcohol consumed (Boyle et al, 2023;Mallett et al, 2019;Waddell et al, 2023). For example, a recent daily diary study (Boyle et al, 2023) found that simultaneous use was only associated with elevated consequences when comparing light drinking simultaneous use days to light drinking alcohol-only days; on heavy drinking days, simultaneous use was not associated with greater consequences than alcohol-only use.…”