Jodi L Ford et al examined the concentration of the stress hormone cortisol in the hair to predict depressive symptoms in adolescents. The study included 432 adolescents between 11 to 17 years of age. The researchers measured depression with a nine-item questionnaire that the participants filled out and evaluated a 3-centimeter hair sample to assess cortisol levels for three months. Researchers observed that both low and high cortisol had a statistically significant relationship to depression. The findings showed a significant curvilinear relationship (b = 0.039, se = 0.01, p-value = 0.005) between hair cortisol and depressive symptoms. Researchers suggest that hair cortisol may be a useful biomarker as it is a retrospective and longer-term measure of the mean cortisol level. However, better understanding of the biological mechanisms is needed to study how cortisol may contribute to depressive symptoms and psychopathology.
Source: Psychoneuroendocrinology, 8 July 2019 Volume 109, November 2019, 104376 DOI: 10.1016/j.psyneuen.2019.104376 https://linkinghub.elsevier.com/retrieve/pii/S030645301930191X