Methods: The data used for this analysis is the National Longitudinal Study of Adolescent to Adult Health, which consists of 5 waves. At Wave 1, participants were in 7th-12th grade (1995) and by Wave 5, participants were 32-42 years old (2016). The main predictors of interest are self-reported experiences of physical and sexual abuse, which was collected retrospectively at Wave 3. Polysubstance use profiles included cigarette smoking, binge drinking, marijuana, and illicit substance use (including a new opioid use indicator in Wave 5). Latent transition analysis was utilized to model changes in profile membership over time. All analyses were conducted in R 3.5.1 and Mplus 8.1.
Results: Among the participants, 29% (n=3,996) reported experiencing physical abuse and 5% (n=645) reported experiencing sexual abuse before 6th grade. Preliminary results showed that physical abuse increased the likelihood of membership in different polysubstance use profiles depending on the time period. For example, physical abuse predicted membership in a profile characterized by cigarette use in adolescence (Wave 2 OR: 1.21; 95% CI: 1.03, 1.41) while predicting binge drinking in early adulthood (Wave 3 OR: 1.60; 95% CI: 1.26, 2.03) as compared to a low/non-use class. Sexual abuse also showed a time-dependent effect on polysubstance use profiles. For example, sexual abuse was associated with a decreased likelihood in profile membership characterized by binge drinking in early adulthood (Wave 3 OR: 0.40; 95% CI: 0.27, 0.60) compared to a low/non-use class. There was evidence of a time-varying effect of physical and sexual abuse on changes in polysubstance use profiles differentiated by cigarette use. For example, physical abuse was associated with a higher probability of transitioning into a regular cigarette use profile in early adulthood (OR: 1.51; 95% CI: 1.08, 2.12).
Conclusions: The effects of physical and sexual abuse on polysubstance use may manifest differently across the life course. Future analyses of the forthcoming complete Wave 5 data will further inform the polysubstance use profiles to incorporate the newly added opioid use indicator.