Sex, Drugs, and Early Risk: Sexual Debut and Substance Use Across Adolescence

• In Event: 3-167 - The Intergenerational Transmission of Substance Use: Preventive and Contributing Mechanisms

Integrative Statement

Sexual debut, or first sexual intercourse, is a normative part of adolescent development (Halpern & Haydon, 2012). However, sexual debut is also associated with certain problematic outcomes including substance use (Zimmer-Gembeck & Helfand, 2008). This association has motivated concern that early sexual activity may promote substance use whereas some scholars question whether there is a potential to pathologize sexual activities. A resolution of this debate requires better evidence. Early sexual debut may be a salient developmental milestone that predicts an increase in substance use behaviors for adolescents (i.e., within-person change), and/or an individual difference variable (e.g., timing of debut) that mostly reflects stable genetic and environmental vulnerabilities such as parental substance use for problem behavior (i.e., between-person differences). Methodologies that can effectively distinguish between these types of effects are crucial.

We examined the associations between sexual debut and substance use in a sample of Mexican-origin youth (N = 674) followed annually from the 5th (Mage = 10.86 years, SD = 0.51) through the 12th grade (Mage = 17.69 years, SD = 0.48). Four substance use variables – lifetime experimentation, frequency of use, substance use intentions, accessibility of substances – were considered. Several early-life risk factors for problem behavior at both the person (e.g., Effortful Control) and contextual level (e.g., parental monitoring, parental substance use) that were measured in 5th and 7th grade were also included. Data were analyzed using a latent curve model with structured residuals (Curran et al., 2014), with sexual debut included as both a time varying and time invariant covariate (Curran et al,. 2012; Figure 1). This allowed within-person effects of sexual debut to be examined while controlling for general-age related trends in substance use, and stable between person differences in those trends based on timing of sexual debut, and early risk factors.

After accounting for the fact that substance use increases as youth age, and that longstanding and persistent developmental influences push some youth towards more substance use and early sexual behavior, sexual debut was still a modest within-person predictor of greater substance experimentation, frequency of use, intent to use, and access to substances. Coefficients were small, but consistent in sign and magnitude across variables and models (Table 1). Results therefore suggest that sexual debut was predictive of greater than expected substance use even after controlling for the fact that substance use increases across adolescence, that youth that sexually debut earlier use more substances, and that early familial and contextual risk predispose some youth to both problematic substance use and early sexual activity. Results did not differ across boys and girls. Altogether, this work reinforces the importance of both early risk factors such as early behavior problems while supporting the idea that sexual debut itself may foretell an uptick in substance use. We plan to extend the current analyses to test whether contemporaneous exposure to parental substance use exacerbates these processes to embed intergenerational issues into developmental frameworks emphasizing both within- and between-person processes.

Authors

• Angus Clark, University of Michigan
  Presenting Author

• Brent Donnellan, Michigan State University
  Non-Presenting Author

• Emily Durbin, Michigan State University
  Non-Presenting Author

• Amy K Nuttall, Michigan State University
  Non-Presenting Author

• Brian M. Hicks, University of Michigan
  Non-Presenting Author

• Richard W. Robins, University of California, Davis
  Non-Presenting Author