1 in 5 college cannabis users showing problematic use patterns

Cannabis use and cannabis-related harms remain important public health concerns among college-age adults. However, nationally representative estimates that characterize the severity of problematic cannabis use in U.S. college students are limited. Using pooled American College Health Association-National College Health Assessment (ACHA-NCHA) III data, we developed a screening-based index of cannabis involvement severity and examined mental health and other correlates. This cross-sectional study used pooled ACHA-NCHA III data from Fall 2019 to Spring 2024. Cannabis involvement severity was operationalized using cannabis-specific items from the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) module embedded in the ACHA-NCHA III (e.g., use frequency, craving/urge, difficulty controlling use, role impairment, and cannabis-related problems). Indicator responses were summed and categorized as no/low involvement (0-1), mild (2-3), moderate (4-5), or severe/high involvement (≥ 6). We estimated prevalence overall and among students with lifetime cannabis use. Ordinal logistic regression identified correlates of greater involvement severity among those with lifetime cannabis use. Modified Poisson and log-linear models assessed associations between involvement severity and mental health indicators among students with cannabis use history. The prevalence of elevated problematic cannabis involvement (score ≥ 2) was 8.66% among all students and 20.77% among those with lifetime cannabis use; among students with cannabis use history, 7.32% had mild involvement, 6.88% moderate involvement, and 6.56% severe/high involvement. Greater involvement severity was more common among males, American Indian/Alaskan Native/Non-Hispanic (NH) Black/NH Other/NH multiracial students (compared with NH White), undergraduates (compared with Master's/PhD students), and those not living on campus, and was associated with greater co-occurring tobacco/other substance use and greater counts of chronic mental health conditions. Compared to students with no/low cannabis involvement, those with mild/moderate/severe involvement had higher prevalence of anxiety, depression, other mental health conditions, and mental health service receipt, as well as higher non-specific serious mental illness, loneliness, and suicide behavior scores. Problematic cannabis involvement is common among U.S. college students and shows a graded association with adverse mental health indicators. These findings support targeted screening and integrated behavioral health services for students reporting more severe patterns of cannabis involvement.