Depressive symptoms and vaping: The mediating effect of outcome expectancies among young adults

The purpose of the present study was to determine if positive affect reinforcement and social enhancement outcome expectancies mediate the longitudinal association between depressive symptoms and frequency of electronic nicotine delivery systems (ENDS) use one year later among young adults.

Participants were 1567 young adults participating in the first three waves of the Marketing and Promotions Across Colleges in Texas project. At Wave 1 participants were 18-25 years old (M = 20.27; SD = 1.86), 61.46% female; 36.25% non-Hispanic white, 33.95% Hispanic/Latino, 14.10% Asian, 7.72% African American/Black, 7.98% two or more races/ethnicities or another race/ethnicity. The independent variable, depressive symptoms, was assessed with the CES-D-10 at Wave 1. The mediating variables, positive affect reinforcement and social enhancement ENDS outcome expectancies were assessed using items adapted from the Youth Tobacco Survey at Wave 2 six months later. The outcome variable was frequency of past 30-day ENDS use at Wave 3, one year after Wave 1. A mediation model was used to test the study hypothesis.

Positive affect reinforcement ENDS outcome expectancies (b = 0.013, SE = 0.006, Bootstrap 95%CI: [0.003, 0.025]), but not social enhancement expectancies (b = -0.004, SE = 0.003, Bootstrap 95%CI: [-0.010, 0.0003]), mediated the positive association between elevated depressive symptoms and frequency of ENDS use one year later.

Results indicate young adults experiencing elevated depressive symptoms may use ENDS at a greater frequency than their peers because they believe ENDS use will alleviate stress, increase relaxation and/or concentration.