Background: Emerging adulthood is a common and problematic time for alcohol and cannabis use. Emerging adulthood also represents a vulnerable time period for anxiety and depression. Substance use and mental health issues are highly comorbid, yet substance use is commonly neglected in psychiatric care.
Objective: The goal of this study was to categorize the cannabis and alcohol use patterns of emerging adults in psychiatric care and to evaluate relationships with use-related problems, psychiatric symptomatology, and motives for use.
Methods: Participants were emerging adults who were consecutive admissions to a young adult psychiatric partial hospital program from 2017 to 2018. Of 318 participants who completed questionnaires, 244 (76.7%) reported cannabis and/or alcohol use in the previous month. Cluster analyses and analysis of variance tests were conducted to categorize and differentiate between participants who reported use.
Results: Results from cluster analyses identified 4 categories of use: low cannabis/high alcohol (35.7%), low cannabis/low alcohol (17.6%), high cannabis/low alcohol (29.1%), and high cannabis/high alcohol (17.6%). Individuals in categories with the highest rates of use and co-use reported more alcohol problems (F=24.31, P<0.001), cannabis problems (F=36.75, P<0.001), depression (F=3.60, P=0.01), and motives: social (F=6.12, P<0.001), coping with anxiety (F=20.43, P<0.001), coping with depression (F=17.80, P<0.001), enhancement (F=7.85, P<0.001), and conformity (F=4.92, P<0.01).
Conclusions/importance: Clear categories of substance use emerged. Participants who were heavier users were more likely to use to alleviate psychiatric symptomatology, yet they also reported greater psychiatric symptomatology and use-related problems. Among a psychiatric sample of emerging adults, cannabis and alcohol use was common and problematic. Thus, substance use should be evaluated for and, if present, targeted with interventions during psychiatric care.