Prevalence of marijuana use at college entry and risk factors for initiation during freshman year

• The study included responses from 3146 students from 11 colleges in NC and VA.
• Nearly 30% of students reported lifetime use of marijuana at college entry.
• We observed a marijuana initiation rate of 8.5% during freshman year.
• We identified several predictors of marijuana use at entry into college.
• We identified several predictors of marijuana initiation over freshman year.

BackgroundMarijuana is currently the most commonly used drug on college campuses. Marijuana use among college students is increasing, and many students begin using marijuana during college. The goal of this study was to investigate predictors of lifetime marijuana use at college entry and initiation during freshman year.MethodsWe used responses from the first two semesters of a longitudinal study of 3146 students from 11 colleges in North Carolina and Virginia. Random-effects logistic regression models were constructed to identify factors that predict lifetime marijuana use at college entry and initiation during freshman year.ResultsNearly 30% of students reported ever having used marijuana at college entry. Among students who had never used marijuana prior to college, 8.5% initiated use during freshman year. In multivariable logistic regression models, having at least $100 per month in spending money; attending church rarely or never; current use of cigarettes, alcohol, and hookah tobacco; lifetime use of other illicit drugs; and a higher propensity toward sensation seeking were associated with a higher likelihood of having used marijuana at least once at college entry. Hispanic ethnicity, living on campus, and current use of cigarettes and alcohol were associated with a higher likelihood of initiating marijuana use during freshman year.ConclusionThese results have implications for targeting substance abuse prevention programs on college campuses.