College Students' prescription drug misuse over time and links with their mental health and well-being.

Prescription drug misuse (PDM) is a mounting public health concern in the U.S., particularly among college students. The field's reliance on cross-sectional designs and limited controls for other substance use has failed to capture the specific role of misuse for longer-term health. Therefore, the present study tested associations between trajectories of PDM problems and college students' mental health and subjective happiness over time. Participants were 300 students who completed a baseline assessment (T1) and follow-ups every 6 months for two years (T2-T5). Participants self-reported problems associated with PDM and mental health. Results from univariate latent growth models indicated that problems with PDM were initially on an increasing trajectory. Based on parallel process models, problems with PDM were concurrently associated with higher levels of depressive symptoms, disinhibition, callousness/aggression, and lower levels of subjective happiness at T1. Further, we found support for parallel trajectories between PDM problems and both depressive symptoms and general disinhibition. Participants whose PDM problems were on an increasing (worsening) trajectory at baseline showed an increase in depressive symptoms and general disinhibition over the next two years. Participants whose PDM problems accelerated over time (got worse at a faster and faster rate over time) also showed a significant increase in their depressive symptoms over time. Most findings, however, were no longer statistically significant in sensitivity analyses that controlled for alcohol and other drug problems. Findings highlight college as an important time for interventions to prevent substance use and its associated negative consequence on later young adult mental health.