INMA: “Chronic stress in preadolescents: school context, bullying, and risk-taking behavior”


An INMA study investigated the influence of school environment and bullying on hair cortisol concentration. Hair cortisol concentration is a useful biomarker of long-term stress.

Although acute stress can be beneficial and adaptive, chronic stress is thought to be detrimental to several health outcomes, including the stress response. Bullying, defined as a type of aggressive behavior that occurs in the school environment, has been identified as one of the main stress sources among children and adolescents. The association between bullying and cortisol levels, a indicator of chronic stress, has been explored in some studies, and findings were inconsistent.

The main objective of the study was to determine whether bullying, along with other school-related factors (i.e., problems with peers, school environment, and academic performance) could predict chronic stress in preadolescents. Authors also considered whether risk-taking behaviors function and sex may modify this association.

At the 11-year-old visit, a total of 659 children from Gipuzkoa and Sabadell were included. Cortisol concentrations were measured in hair strands of 3cm, to reflect the chronic stress of the past 3 months. Bullying experience in the past 2 months were estimated using the validated Olweus Bully Victim Questionnaire. Other environmental and behavioral variables, including school environment, problems with peers, risky decision making and academic achievement, were recorded using questionnaires at the 11-year-old visit.

The results suggest that being involved as a bully or a victim was related to higher cortisol levels and, higher cortisol concentration was associated with more risk-taking behavior. This is the first study showing the association of different roles that children may take in bullying with cortisol concentration. Authors say that the study “allows to gain a deeper understanding of the relationship between school stressors and neurophysiological function”. Besides, they plead for programs of prevention and intervention that “could modify individual physiological responses to stress and reduce the effects of stress on the health”.

Reference: Babarro I, Ibarluzea J, Theodorsson E, Fano E, Lebeña A, Guxens M, Sunyer J, Andiarena A. Hair cortisol as a biomarker of chronic stress in preadolescents: influence of school context and bullying. Child Neuropsychol. 2022 Aug 28:1-18. doi: 10.1080/09297049.2022.2115991. Epub ahead of print. PMID: 36036166.

Link to the scientific article: