Hair Cortisol Concentrations in the Prediction of Early Substance Use Engagement in Youth.

OBJECTIVE

Understanding factors associated with early onset of substance use is critical as using alcohol or drugs at a young age is a strong predictor of later substance dependency. Experiencing stressful life events is associated with increased risk for early substance use in youth. Hair cortisol concentration (HCC) is considered a biomarker of psychological stress experienced over longer periods of time. We examined whether HCC could predict early substance use engagement in youth followed over 5 years.

METHODS

Participants were 395 young adolescents (50% female, age range 10-15 years, = 12.3,  = 1.1 at baseline). Demographic data, socioeconomic factors, and substance use habits were collected at four waves between 2015 and 2021. HCC was assayed from hair collected at a home visit between Wave 1 and Wave 2. Analytic models tested HCC in relation to latent class membership of substance use and whether HCC moderated the relation between self-reports of stress and substance use.

RESULTS

HCC did not add to the prediction of early substance use engagement in any of the models, while self-reports of stressful life events and everyday discrimination predicted early substance use engagement in the models comparing 'Early' vs 'Late/No' substance use class membership.

CONCLUSION

We found no evidence of HCC to be associated with early substance use engagement in youth. Nevertheless, our results do confirm that self-reports of stressful everyday life experiences predict earlier substance use engagement, underscoring the role of psychosocial stressors as significant predictors of substance use engagement in youth.