Background: Alcohol, cannabis, and tobacco use are prevalent in young adults and may be differentially related to psychological symptoms characterized as externalizing or internalizing.
Objectives: This study examined the use of alcohol, cannabis, and various tobacco products in relation to externalizing (ADHD) versus internalizing factors (depression, anxiety), hypothesizing alcohol and cannabis use are associated with externalizing factors whereas tobacco use is related to internalizing factors.
Methods: Data from a 2-year longitudinal study of 2,397 US college students (aged 18-25) launched in 2014 were analyzed. Adult ADHD Self-Report Scale, Patient Health Questionnaire-9 item (assessing depressive symptoms), and the Zung Self-Rating Anxiety Scale scores were examined in relation to subsequent past 30-day use of alcohol, cannabis, and tobacco products (cigarettes, little cigars/cigarillos, smokeless tobacco, e-cigarettes, hookah), as well as nicotine dependence per the Hooked on Nicotine Checklist.
Results: Participants were 20.49 (SD = 1.93) years old, 64.7% female, and 65.5% White. In multivariable analyses, greater ADHD symptoms predicted alcohol and cannabis use (p = .042 and p = .019, respectively). Cigarette and little cigar/cigarillo use were predicted by greater depressive (p = .001 and p = .002, respectively), and anxiety symptoms (p = .020 and p = .027, respectively). Nicotine dependence was correlated with greater anxiety symptoms (p = .026). Counter to hypotheses, smokeless tobacco use was predicted by greater ADHD symptoms (p = .050); neither e-cigarette nor hookah use were predicted by these psychological symptoms. Conclusions/Importance: Research examining risk factors for tobacco use must distinguish among the various tobacco products. Moreover, interventions may need to differentially target use of distinct substances, including among the range of tobacco products.
Keywords: Substance use; alcohol use; cannabis use; risk factors; tobacco use; young adults.