Hair Cortisol Concentrations in War-Affected Adolescents

Our study is the first to prospectively examine, in war-affected adolescents, the associations between hair cortisol concentrations (HCC) and self-reports of stress, insecurity, post-traumatic reactions, and lifetime trauma. We conducted a randomized controlled trial to test the impact of an 8-week intervention based on profound stress attunement. We collected data for a gender-balanced sample of 733 Syrian refugee (n = 411) and Jordanian non-refugee (n = 322) adolescents (12–18 years), at three time-points. We used growth mixture models to classify cortisol trajectories, and growth models to evaluate intervention impact on stress physiology.

• Three trajectories describe cortisol production of refugee and non-refugee youth.
• Insecurity and female gender predicted a pattern of cortisol hyper-secretion.
• Trauma exposure predicted within-individual cortisol dysregulation.
• The stress-attunement intervention decreased hair cortisol concentrations by a third.
• Effective interventions may normalize cortisol production in war-affected adolescents.

This robust impact evaluation exemplifies the utility of biomarkers for tracking physiological changes in response to interventions over time.