Patterns of Alcohol, Cannabis, and E-Cigarette Use/Co-Use and Mental Health Among U.S. College Students.

Substance use and mental health are highly correlated, though few studies assess the risk for depression and anxiety associated with dual and polysubstance use among college students. The purpose of this study was to characterize the relationship between alcohol, cannabis, and e-cigarette exclusive, dual, and polysubstance use and depression and anxiety among U.S. college students by racial and ethnic subgroup and stratified by sex. Data from 83,467 undergraduate students participating in the 2020-2021 Health Minds Survey, a multi-campus, web-based survey, were used. Sex-stratified logistic regression models examined the effects of exclusive (past 30-day cannabis use, past 30-day e-cigarette use, past 2-week heavy alcohol use), dual (two among cannabis, e-cigarette, or alcohol use), and polysubstance (all three substances) use on anxiety (≥10 GAD-7 score) and depression (≥15 PHQ-9 score). The study included 60,746 females and 22,721 males. Among females, compared to those who exclusively used alcohol, dual users of cannabis and e-cigarette had the largest odds for depression (adjusted odds ratio (aOR) = 1.92) and anxiety (aOR = 1.69) followed by polysubstance users (aORs = 1.85 and 1.53, respectively). Among males, compared to those who exclusively used alcohol, dual users of cannabis and e-cigarette had the largest odds for depression (aOR = 2.72) and anxiety (aOR = 2.23) followed by polysubstance users (aOR = 1.71 and 1.85, respectively). African American female and male students had lower odds of anxiety and depression compared to White students. The results suggest that single, dual, and polysubstance use are associated with anxiety and depression among U.S. college students, though not necessarily in additive ways.