Marijuana Use and Increases in Use over Time among Young Adult College Students in the State of Georgia: Analyses of Sociocontexual Predictors

Abstract

Background

While research has assessed correlates of marijuana use, there has been less focus on predictors of differing levels of changes in use during young adulthood, a critical period for use/escalation.

Objectives

We examined changes in marijuana use and related sociocontextual predictors (e.g., earlier-onset substance use, parental use, college type).

Methods

Using data from Georgia college students (ages 18–25 years) in a 2-year, 6-wave longitudinal study (64.6% female, 63.4% White), 2-part random-effects modeling examined use at any assessment and number of days used.

Results

Predictors of use status at any assessment included being male (OR = 1.87, 95%CI = [1.28–2.73]), Black (OR = 1.91, 95%CI = [1.15–3.19]), earlier-onset marijuana (OR = 2.63, 95%CI = [1.70–4.06]), cigarette (OR = 2.04, 95%CI = [1.19–3.48]), and alcohol users (OR = 1.49, 95%CI = 1.00–2.22]), parental tobacco (OR = 2.14, 95%CI = [1.18–3.86]) and/or alcohol use (OR = 1.55, 95%CI = [1.09–2.20]), and attending private (vs. public) institutions (OR = 1.68, 95%CI = [1.10–2.59]). Predictors of lower likelihood of use over time included being male (OR = 0.87, 95%CI = [0.77–0.98]), earlier-onset cigarette use (OR = 0.82, 95%CI = [0.68–0.98]), parental alcohol use (OR = 0.86, 95%CI = [0.77–0.97]), and private institution students (OR = 1.17, 95%CI = [1.02–1.34]). Predictors of more days used at baseline included being male (OR = 1.77, 95%CI = [1.40–2.23]), Black (OR = 1.42, 95%CI = [1.04–1.93]), earlier-onset marijuana (OR = 2.32, 95%CI = [1.78–3.01]) and alcohol users (OR = 1.29, 95%CI = [1.01–1.66]), and parental tobacco use (OR = 1.90, 95%CI = [1.32–2.73]). Predictors of fewer days used over time included being older (OR = 0.98, 95%CI = [0.97–1.00]), parental tobacco use (OR = 0.86, 95%CI = [0.78–0.95]), and attending private institutions (OR = 0.89, 95%CI = [0.83–0.93]).

Conclusions

Intervention efforts can be informed by current findings that correlates of baseline use (e.g., being male, attending private institutions) also predicted less use over time, and one’s earlier use and parents’ use of various substances impacted young adult use.

Keywords:

• Substance use
• young adults
• risk factors
• marijuana use

Acknowledgment

This research was supported by the US National Cancer Institute (1R01CA179422-01; PI: Berg). Dr. Berg is also supported by other US National Institutes of Health funding, including the National Cancer Institute (R01CA239178-01A1; MPIs: Berg, Levine; R01CA215155-01A1; PI: Berg), the Fogarty International Center (1R01TW010664-01; MPIs: Berg, Kegler), the National Institute of Environmental Health Sciences/Fogarty (D43ES030927-01; MPIs: Berg, Marsit, Sturua), and the National Institute on Drug Abuse (R56 DA051232-01A1; MPIs: Berg, Cavazos-Rehg). The funders had no role in the study design, collection, analysis or interpretation of the data, writing the manuscript, or the decision to submit the paper for publication.

Contributors

Berg, Haardörfer, and Windle designed the study and wrote the protocol. Haardörfer conducted the analysis and contributed to the writing of the manuscript. Berg wrote the first draft of the manuscript, with Windle, Haardörfer, Dodge, Cavazos-Rehg, Yang, and Ma contributing additional components to the manuscript. All authors contributed to and have approved the final manuscript.

Declaration of interest

No conflict declared.

Data availability statement

Specific data shared upon request submitted to authors.

Additional information

Funding

This research was supported by the the US National Cancer Institute (1R01CA179422-01; PI: Berg). The funders had no role in the study design, collection, analysis or interpretation of the data, writing the manuscript, or the decision to submit the paper for publication.