Young adults who use cannabis and alcohol together on the same day are driven more by cannabis-related motivations | Research

The takeaway

On days when young adults used both alcohol and cannabis, cannabis-related enhancement and social motives were the strongest predictors of co-use.

Young adults who combine alcohol and cannabis, substance use researchers, prevention program designers

237 co-use days recorded, driven primarily by cannabis enhancement motives

What the researchers found

Greater cannabis-related enhancement and social motives were associated with increased likelihood of same-day alcohol/cannabis co-use compared to cannabis-only days. Alcohol-related social motives showed a weaker, non-significant association in adjusted models.

Why it matters

Same-day use of alcohol and cannabis increases the risk of negative consequences. Understanding that cannabis-related positive affect motives drive co-use may help intervention programs target the right motivations.

The numbers in context

97 participants; ages 18-25; 28 daily assessments; 126 alcohol-only days; 805 cannabis-only days; 237 co-use days

How the study worked

28-day daily diary study of 97 young adults aged 18-25, recruited from an urban emergency department, who received daily text message assessments about substance use and motives. Fixed effects regression estimated within-person effects.

What this study cannot tell us

Emergency department sample may not generalize to the broader population, self-reported motives, relatively small sample, short 28-day observation period.

How to read the evidence

Daily diary study with a small sample from an emergency department setting

When this study was published

Published in 2021 based on data from an urban emergency department population.

The bigger picture

These findings suggest co-use isn't simply about alcohol escalating to cannabis or vice versa. The desire to enhance positive experiences through cannabis appears to be the primary motivator, which could inform how prevention programs address polysubstance use.

Questions still open

Do co-use motives differ in older adults or non-clinical populations? Would interventions targeting enhancement motives actually reduce co-use frequency? What role does the social environment play beyond individual motives?

Common questions

Why do people use alcohol and cannabis together?

This study found that cannabis-related motives for enhancing positive feelings and socializing were the strongest predictors of same-day co-use, more so than alcohol-related motives.

Is using alcohol and cannabis together more risky?

The researchers note that same-day use of both substances increases the risk of negative consequences compared to using either alone, though this study focused on motives rather than outcomes.

Read the original research

Alcohol and cannabis motives: Differences in daily motive endorsement on alcohol, cannabis, and alcohol/cannabis co-use days in a cannabis-using sample.

Addiction research & theory, 29(2), 111-116

View on PubMed ↗Publisher’s paper ↗

Citation

Arterberry, Brooke J; Goldstick, Jason E; Walton, Maureen A; Cunningham, Rebecca M; Blow, Frederic C; Bonar, Erin E. (2021). Alcohol and cannabis motives: Differences in daily motive endorsement on alcohol, cannabis, and alcohol/cannabis co-use days in a cannabis-using sample.. Addiction research & theory, 29(2), 111-116. https://doi.org/10.1080/16066359.2020.1787390