Hair cortisol may help us better understand the impact of stress on autistic children, new research has found.
Autistic children may be non-verbal or not have the words or other typical communication strategies to clearly explain their feelings. Researchers from Neuroscience Research Australia (NeuRA) and UNSW Sydney have found hair cortisol levels may complement behavioural assessments for determining the impact of chronic stress.
Dr Adam Walker from NeuRA’s Laboratory of ImmunoPsychiatry said the research explored the relationship between chronic stress, co-occurring conditions, sleep and autistic features, such as severity, using clinical data and biological samples from the Autism CRC Australian Autism Biobank, and supported by Early Life Determinants of Health (ELDoH) Clinical Theme of Sydney Partnership for Health, Education, Research and Enterprise (SPHERE).
“While in many situations we can discuss with individuals their experiences and work to understand the interactions between stress, sleep and other factors, this can be difficult for some autistic children,” Dr Walker said.
“Our study wanted to see if hair cortisol concentration could be a biomarker, or new tool, in better understanding the relationship between these factors especially for autistic children who are not able to clearly explain their feelings.”
Researchers used samples from more than 580 autistic children, as well as their non-autistic siblings, and unrelated non-autistic children. The children were aged between two and 17 years of age.
The measurement of hair cortisol concentration is not new. The non-invasive biomarker has been used to provide retrospective data for assessment of stress, mental health and some diseases. During stressful situations, cortisol is incorporated into the hair from the blood, as well as via sweat and sebum over weeks or months. This means hair cortisol can provide insight into a person’s more chronic state of stress and wellbeing. And now researchers have found it may assist autistic children and their families.
“We found that hair cortisol concentration may be an additional way to understand stress and wellbeing in autistic children,” Dr Walker said.
“We found that lower hair cortisol concentration was associated with greater autism severity, particularly internalised distress, behavioural difficulties, and co-occurring ADHD. There were also links between higher hair cortisol concentration and sleep anxiety, night wakings, lower family income and younger children.
“Combining this biological information with behavioural insights can improve our understanding of an individual child’s experience and may guide more personalised support in the future.”
This research is part of a larger strategy by researchers and clinicians at NeuRA, UNSW, and South Western Sydney Local Health District, led by Scientia Professor and Child and Adolescent Psychiatrist, Valsamma Eapen, to integrate biological information with social, environmental and clinical characteristics to get a better handle on the enormous heterogeneity that exists in the autism spectrum so that personalised care strategies can be implemented to help children with neurodevelopmental disorders thrive.
“Since hair cortisol level provides a reliable, non-invasive, 3 – 6month window of chronic stress, it avoids the pitfalls of acute, single-point stress measures using blood, saliva or sweat/sebum, which are also difficult to collect in autistic children,” Prof Eapen said.
“Further, it helps identify hypothalamic-pituitary-adrenal (HPA) axis dysfunction, enabling tailored therapeutic interventions and supports to improve functionality, sleep, and behavioural outcomes.”
The research team thanks the families and children who donated their samples to the Autism CRC Biobank.
The paper was published in Psychoneuroendocrinology and is available here.
