Higher perceived stress and poorer health reflected in elevated cortisol concentrations measured in extracts of hair from middle-aged healthy women
The prevalence of mental strain and stress has increased in modern societies, resulting in increased public health problems. Stress can be measured either by biomarkers or by self-reports. A new biomarker that measures long-term biological stress is cortisol measured in timed hair extracts. Hair grows at approximately 1 cm per month, and retrospectively reflects average stress levels. However, the plausible relationship between perceived stress and self-reported health and this novel biomarker
... is novel biomarker is yet not firmly established. The objective of this study was to investigate the possible relationship between perceived stress, self-reported health, and cortisol in hair extracts in healthy middle-aged women from two different occupations. Method: A cross-sectional study was conducted in 112 middle-aged women working as nurses or librarians in a county in southeast Sweden. The women were invited to fill in a questionnaire covering stress, health, and life situation. The questionnaire included questions on health and disease symptoms, the Perceived Stress Scale (PSS), and the Hospital Anxiety and Depression (HAD) scale. A piece of hair was cut from the vertex posterior area of the head an analysed by a competitive radioimmunoassay method. Results: Middle-aged women who reported high perceived stress (p = 0.031) or lower health (p = 0.029), or had signs of depressiveness (p = 0.016) had significantly higher cortisol concentrations adjusted for age. There were no significant differences in cortisol in hair concentrations or perceived stress between nurses and librarians. Two women with extremely high cortisol concentrations were considered as outliers, but during the interview at follow-up they reported experiences of serious life events in their work or social life during the retrospective time of the sample taken for cortisol measurement. Conclusions: Higher cortisol concentrations measured in the hair of healthy and working middle-aged women were associated with higher perceived stress and generally poorer health and with depressiveness. These findings lend support to the general applicability of cortisol measured in hair extracts as a biomarker in population-based epidemiological studies.