A new study from the University of Waterloo shows that long-term stress, measured through hair samples, could help predict mental health problems in children living with chronic physical illnesses (CPI).
This finding could help doctors give support earlier and improve these children’s lives.
In Canada, around 40 percent of children are living with a chronic illness. These illnesses include conditions like asthma, diabetes, and epilepsy. Living with such illnesses often means children must take regular medicine, miss school, or avoid normal activities.
This can be emotionally hard and may lead to anxiety, depression, or other mental health problems. Children with CPI are more likely to face emotional difficulties compared to children without these health issues.
The research was led by Emma Littler, a PhD student in Public Health Sciences. Her team followed 244 children in Canada who were living with CPI. They studied the children’s stress levels by measuring cortisol in their hair.
Cortisol is a hormone that rises when a person is stressed. Hair samples provide a way to measure how much stress a person has felt over a longer period—weeks or even months.
The researchers found that more than two-thirds of the children had high levels of cortisol in their hair for a long time. These children were more likely to show signs of anxiety, depression, or other emotional and behavioral problems. In contrast, children whose cortisol levels went down over time were less likely to have these mental health symptoms.
This means that measuring hair cortisol might help doctors find out which children with chronic illnesses are most at risk for mental health problems. If these risks are discovered early, families and doctors can step in with support, therapy, or programs that help reduce stress.
Dr. Mark Ferro, a professor and co-author of the study, said that using hair cortisol could be an easy and non-invasive way to find children who need extra care. Since it only requires a small hair sample, it could be done easily during a regular doctor’s visit.
The findings were published in the journal Stress and Health in a paper titled “Association between hair cortisol and psychopathology in children with a chronic physical illness.”
In addition to the hair study, the same research team also looked at blood tests from children with CPI. They found that certain substances in the blood, called biomarkers, could also help predict mental health outcomes.
Some of these markers were linked to worse mental health over time, while others were linked to improvements. This shows that blood tests and hair samples together could help provide a clearer picture of how a child is doing emotionally.
These studies suggest that medical check-ups for children with chronic illnesses could one day include stress tests using hair or blood. This would help doctors give better care, spot mental health problems early, and help children get the support they need to live healthier and happier lives.
The study is published in Stress and Health.
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