Summary: Long-term stress, measured through hair cortisol, may help predict mental health risks in children living with chronic physical illnesses. In a four-year study of 244 children, researchers found that persistently high cortisol levels were strongly linked to anxiety, depression, and behavioral difficulties.
Children whose cortisol levels declined showed fewer symptoms, suggesting stress relief is protective. The findings highlight a simple, non-invasive tool that could guide early intervention and support for vulnerable children.
Key Facts
- Stress Signal: Hair cortisol offers a long-term measure of stress exposure.
- High-Risk Group: Children with chronic illnesses and persistently high cortisol had more mental health problems.
- Early Action: Screening could help identify and support at-risk children sooner.
Source: University of Waterloo
Long-term stress levels, measured through hair samples, may provide important clues about mental health risks in children with chronic physical illnesses (CPI), according to new research from the University of Waterloo.
The study highlights how high hair cortisol, a type of steroid hormone, acts as a powerful early warning sign that could help identify children who live with CPI and who could be most at risk of mental health challenges, helping guide prevention and treatment strategies to better support their health and well-being.
An estimated 40 per cent of children in Canada live with a CPI — a number that has been rising steadily for decades. These children face a much higher risk of developing mental health problems than their healthy peers, putting them at greater risk for poor quality of life, suicidal thoughts and increased reliance on health-care services.
“Living with a chronic illness means facing daily challenges such as taking medications, missing school and adjusting activities, all of which can take a serious emotional toll,” said Emma Littler, a Waterloo PhD candidate in Public Health Sciences and lead author of the study.
“Our findings suggest that chronically high stress, measured through hair samples, could help identify children with CPI at the highest risk for developing mental health problems. This opens the door to earlier and more targeted support.”
The study followed 244 Canadian children with chronic physical illnesses over four years, measuring stress using hair cortisol — a biological marker that reflects stress levels over time. Researchers found that more than two-thirds of these children had persistently high cortisol levels.
Those children were also more likely to show symptoms of depression, anxiety, or other mental health concerns compared to peers whose cortisol levels decreased over time.
When the researchers compared these patterns to reports of emotional and behavioural difficulties, they found that children whose cortisol levels declined over time showed fewer symptoms of anxiety, depression and behaviour problems than those whose cortisol levels stayed high.
“Identifying these risk factors early could help doctors and families intervene before emotional and behavioural difficulties take hold,” said Dr. Mark Ferro, a professor in Waterloo’s School of Public Health Sciences and co-author of the study.
“Hair cortisol offers a non-invasive, easy-to-collect biomarker that could one day be used to screen children and track whether treatments or support programs are helping to reduce stress.”
The study, Association between hair cortisol and psychopathology in children with a chronic physical illness, was recently published in Stress and Health.
Ferro and colleagues from Waterloo and McMaster University also published new research showing that biomarkers found in the blood of children with CPI may help predict future mental health challenges.
The study, Inflammatory biomarkers predictive of psychopathology in children with physical illness, found that some blood signals were linked to children with CPI experiencing worsening mental health over time, while others were associated with improvements.
The findings suggest that routine blood tests, combined with mental health check-ups, could help doctors identify children who may need extra support earlier.
About this mental health and neurodevelopment research news
Author: Ryon Jones
Source: University of Waterloo
Contact: Ryon Jones – University of Waterloo
Image: The image is credited to Neuroscience News
Original Research: Open access.
“Association Between Hair Cortisol and Psychopathology in Children With a Chronic Physical Illness” by Emma Littler et al. Stress and Health
Abstract
Association Between Hair Cortisol and Psychopathology in Children With a Chronic Physical Illness
Children with a chronic physical illness (CPI) experience significant stress and are at a greater risk of psychopathology. However, little is known about chronic stress and its relationship with psychopathology in this population. Over the last decade, hair cortisol concentration (HCC) has emerged as a viable biomarker of chronic stress.
This study identified trajectories of HCC in children with a CPI and examined their associations with psychopathology.
The study included data from 244 children enroled in the Multimorbidity in Children and Youth across the Life-course (MY LIFE) study. MY LIFE is a prospective study of children aged 2–16 years with a CPI recruited from outpatient clinics at a Canadian paediatric hospital and followed for 48 months.
Children provided 3-cm hair samples for cortisol assay and parents reported psychopathology symptoms using the Emotional Behavioural Scales. We identified three HCC trajectories: (1) Hypersecretion (n = 166, 68.03%); (2) Hyposecretion (n = 21, 8.61%); and (3) Hyper-to-Hypo (n = 57, 23.36%).
When adjusting for sociodemographic and clinical characteristics, children in the Hyper-to-Hypo class had lower internalising (β = −3.17, p = 0.005) and externalising (β = −2.27, p = 0.007) psychopathology symptoms compared to the Hypersecretion class. This study provides evidence that children with a CPI follow distinct HCC trajectories.
Children who followed a decreasing trajectory exhibited lower psychopathology symptoms compared to children who followed a consistently elevated trajectory, indicating that chronically high cortisol levels may contribute to the development of psychopathology.
