Scientific Meeting 2023 - Lightning Talks Day 3

Wednesday, March 15
09:00am to 09:45pm

Presenter: Tzung-Shiang Ou

Trajectories of Polysubstance Use: Are Internalizing and Externalizing Problems Associated with Trajectories of Polysubstance Use?

Ou, Tzung-Shiang; Huber, Lesa; Macy, Jonathan; Chow, Angela; Lin, Hsien-Chang

Purpose: Polysubstance use among adults has been a public health concern in the U.S. and is associated with adverse consequences. Understanding the longitudinal trajectory of polysubstance use and associated predictive factors is an essential step in the effort to mitigate the polysubstance epidemic. The current study aimed to identify the longitudinal trajectory of polysubstance use and whether internalizing and externalizing problems predict it.

Methods: Adults aged 18 and older (N=18,925) were extracted from the Waves 1-5 Population Assessment of Tobacco and Health (PATH) Study. Group-Based Trajectory Modeling (GBTM) was performed to identify the trajectory of polysubstance use. Examined substances included use of cigarettes, e-cigarettes, excessive alcohol, marijuana, painkillers, and cocaine in past 30 days from all waves. Weighted multinomial logistic regressions were conducted to investigate the associations between internalizing problems and externalizing problems and the trajectory of polysubstance use, controlling for demographic variables.

Results: Five polysubstance use trajectory groups were identified: (1) Polysubstance use--low risk (10.5%); (2) No to minimal polysubstance use risk (46.3%); (3) Cigarette-leading polysubstance use--high risk (23.2%); (4) Cigarette-marijuana co-leading polysubstance use--high risk (12.3%); and (5) Marijuana-leading polysubstance use--high risk (7.7%). Compared with Group 2, higher internalizing problems predicted the membership of Group 3 [Relative risk ratio (RRR) range: 1.07 to 1.17] and Group 4 (RRR range: 1.04 to 1.21). Compared with Group 2, higher externalizing problems predicted the membership of Group 5 (RRR range: 1.01 to 1.10).

Conclusion: This was the first study that identified the U.S. national trajectories of polysubstance use among adults within the period of 2013 - 2019. The results suggested that internalizing externalizing problems predicted the trajectories of high-risk polysubstance use. Prevention efforts should consider internalizing and externalizing problems and associated different trajectories of polysubstance use when designing polysubstance use prevention interventions.