Since February 2022, more than 45,000 air alarms have sounded across Ukraine and more than 12,000 explosions have devastated the country. For young people living there, these are not distant events, but part of daily life. A new study by Ann T. Skinner, research professor at Duke University; Iuliia Pavlova; Jennifer Godwin; Emily B. Reilly; and Anastasia Georgiades examines how this ongoing exposure to war is associated with both psychological distress and a biological marker of chronic stress.
The study, Hair Cortisol Concentrations among Youth in Ukraine: Associations with War Experiences and Post-Traumatic Stress Symptoms, is the first known to examine relations among youth hair cortisol concentrations (HCC), war exposure, and psychological distress in an active war zone. The research team collected data from 221 youth (average age 18.9; 20% male) living in five regions of Ukraine between November 2023 and March 2024. Participants provided hair samples to assess HCC, a measure of cumulative cortisol secretion over weeks to months, and completed self-report surveys measuring post-traumatic stress (PTS) symptoms. The researchers also matched each participant’s region of residence to objective data on air alarms and explosions.
Hair cortisol offers a window into longer-term stress physiology. Unlike salivary cortisol, which reflects momentary or short-term responses, hair cortisol captures patterns of cortisol output over time. This makes it especially useful for understanding chronic stress, such as living under sustained threats during war.
The findings were consistent with prior research on chronic stress and the body’s stress-regulation system, the hypothalamic–pituitary–adrenal (HPA) axis. Youth who experienced more air alarms had lower hair cortisol concentrations. The same pattern emerged for exposure to explosions: greater exposure was associated with lower HCC. Contrary to the researchers’ hypotheses, however, hair cortisol was not related to PTS symptoms. In this sample, physiological stress levels and self-reported post-traumatic stress symptoms did not move together.
Research suggests that while acute or recent threat is often associated with elevated cortisol, prolonged or severe stress can lead to down-regulation of cortisol production over time. This pattern may represent an adaptation to chronic adversity. At the same time, lower long-term cortisol output may carry risks, including immune dysregulation or increased inflammatory activity. Adolescence and young adulthood are periods of ongoing development in stress-regulatory systems, which may make youth particularly sensitive to unpredictable and sustained environmental danger.
Collecting these data during an active invasion required unusual speed and coordination.
Dr. Skinner explained, “As you can imagine, collecting data from families in an active war zone is both challenging and time sensitive. Traditional grant mechanisms would have taken at least many months if not years from submission to funding; the SSRI timeline was one of the only funding sources I know that provided such a rapid turnaround in both application decisions and funding, critical to our work.”
Rapid support made it possible to launch data collection in late November 2023 and gather responses from youth across multiple regions, including some near the front lines.
Much of the existing research on trauma and cortisol has focused on adults or on individuals who have already left conflict settings. This study addresses that gap by examining youth who are living through ongoing war-related exposure. By combining objective regional data on air alarms and explosions, self-reported psychological distress, and a biological marker of chronic stress, the study provides new evidence on how prolonged conflict may be associated with both physiological and psychological responses in young people.
The findings are especially relevant in Ukraine, where stigmatization of mental health treatment can be a barrier to seeking care. The researchers note that future work should include context-sensitive measures of ongoing stress and coping and examine how potential protective factors, such as social support, may mitigate the effects of sustained conflict.
For Ukrainian youth growing up during war, stress is not a single event, but an ongoing condition. This study offers important new insight into how that reality may be reflected not only in psychological distress, but also in the body’s long-term stress response.
The four-year anniversary of the full-scale Russian invasion of Ukraine is February 24, 2026. This date marks four years since the conflict began on February 24, 2022, with international leaders and Ukraine observing this milestone in Kyiv on that day.
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