The association between undergraduate majors and substance use and how mental health status affects that relationship

Previous findings demonstrate variability in substance use among undergraduate majors and demonstrate significant relationships between mental health status and substance use. However, there is a gap in the literature on whether mental health status plays a role in the relationship between college majors and substance use. This epidemiological study, which aims to address that gap, examined the relationship between major and substance use as the first goal. Its secondary goal was to examine how that relationship changed when accounting for mental health status. The study data stems from the Healthy Minds Survey, which is a public and cross-sectional dataset. Arts & Humanities, STEM, Business, Education, and Social Sciences, Health, and Undecided and Other college majors were considered, with STEM used as the reference group. Substance use was defined as stimulants, opioids, hallucinogens, binge drinking, marijuana, cigarettes or vaping (nicotine), kratom, and benzodiazepines. Mental health status was operationalized as two types of variables: mental health symptom scales and mental health diagnoses. This study utilized logistic regression, focusing on a yes/no outcome for each substance by undergraduate major. Two categories of models were created: one that did not adjust for mental health variables, which included the mental health symptom scales and mental health diagnoses and mental health treatment, and another that did. Covariates that were in both models included variables capturing demographics which included but were not limited to family education level, chronic disease conditions, age, sexual orientation, and gender. Other covariates included chronic health conditions and substance use screening questions. There were statistical differences in the rate of substance use across majors. The relationship between undergraduate majors and substance use had inconsistent variations when adjusted for mental health status. In general, the associations between undergraduate major and substance use were relatively stable with and without adjustment for mental health. This suggests that mental health does not play a substantial role in the relationship of undergraduate majors and substance use.