Association between marijuana use with alcohol use and consequences throughout first 2 years of college
Entering college is associated with marijuana use as well as increased alcohol use. A recent study looked at marijuana as a factor in the amount of alcohol consumed as well as the consequences of students who used alcohol and marijuana.
A sample of 488 traditional college students who were entering their first year and had a history of alcohol and marijuana use was surveyed biweekly for two years. These surveys included daily alcohol use, daily marijuana and cigarette use, and weekly alcohol-related consequences.
The results showed that on days that participants used marijuana, they consumed more alcohol compared to days that they did not. The study also showed that weekly marijuana use was linked to experiencing more positive and negative alcohol-related consequences. The relationship between marijuana use and alcohol use strengthened over time, meaning that students increasingly used alcohol on days that they used marijuana.
Weekly marijuana users reported more frequent alcohol-related consequences. Reports of positive consequences of alcohol use weakened over time, though the amount of negative consequences did not change. There was no observed reduction in use of both marijuana and alcohol, meaning that the initial positive effects of co-use may explain why the students maintained their use behaviors.
Also, students who drank heavily before entering college were more likely to consume more alcohol on days in which they used marijuana, and to experience more negative consequences due to alcohol while using more marijuana. This suggests that marijuana may increase the severity of the effects marijuana has on alcohol use more significantly in this population.
This study was the first to display longitudinal evidence on the effects that marijuana use has on student alcohol use and outcomes, and provides interesting evidence for co-use of the two substances among students.
Take away: Marijuana use leads to increased alcohol use, as well as an increase in positive and negative alcohol-related outcomes in college students. These effects are more prominent in college students who used alcohol before entering college.
Genn, R.L., Norris, A.L., Sokolovsky, A., et al. (2018). Marjuana Use is Associated With Alcohol Use and Consequences Across the First 2 Years of College. Psychology of Addictive Behaviors. doi.org/10.1037/adb0000416