A new study published in the Journal of Stress and Health looked at the association between hair cortisol and psychopathology in children with a chronic physical illness.
“This study explores how stress, measured using hair cortisol, may contribute to the onset of mental health problems in children with a chronic physical illness (CPI),” lead study author and University of Waterloo PhD candidate in Public Health Sciences, Emma Littler told us. “We were investigating whether hair cortisol could be used to identify children at the highest risk of developing mental health problems.”
Children with a CPI face repeated demands of living with a chronic condition such as treatments, school absenteeism, and restrictions in daily life. The researchers hypothesized that a large proportion of children would exhibit elevated hair cortisol levels over time. Based on previous research, the researchers also hypothesized that children with elevated hair cortisol levels would exhibit more severe mental health problems.
“Estimates suggest that approximately 20% of Canadian children will experience a mental disorder, and without effective prevention and treatment, mental disorders can persist into adulthood and have adverse long-term consequences,” Littler told us. “Thus, research aimed at understanding the determinants of childhood mental disorders is critical. While there is extensive evidence on the link between childhood stress and the development of mental disorder, CPI as a major life stressor has not been studied.”
Hair samples were collected from 244 children with a CPI over four years, and statistical modelling was used to identify children who follow distinct trajectories of hair cortisol over time and how these trajectories are associated with mental health problems over time.
“We found that most children with a CPI had chronically high cortisol levels over time,” professor in the Waterloo’s School of Public Health Sciences and study co-author, Dr. Mark Ferro told us. “We also found that children with chronically high cortisol levels exhibited more severe mental health problems compared to children with decreasing cortisol levels.”
Given that children with a CPI may face considerable stress due to their health challenges, Dr. Ferro said it was not surprising that over two-thirds of children had chronically high hair cortisol levels. It was also not surprising that these children exhibited more severe mental health problems.
“Identifying objective risk factors for mental health problems in this population, like high hair cortisol, is critical for informing effective prevention and treatment strategies to improve the health and well-being of children with a CPI,” Dr. Ferro told us. “Future research can explore interventions aimed at reducing stress levels in children with a CPI.”