title: Associations between hair cortisol concentration, income, income dynamics and status incongruity in healthy middle-aged women.
abstract: A body of research demonstrates that financial disadvantage is associated with general health inequalities and higher mortality rates. Most studies make use of cross-sectional analyses, although income can also be viewed as a dynamic concept. The use of endocrine-markers as proxies for health can provide information about the pathways involved in these associations. Hair cortisol analysis has been developed as a method for assessing sustained cortisol output as it provides an estimate of cumulative cortisol secretion over a prolonged time. The present study assessed income and income trajectory over a 4-year period in 164 working women (aged 26-65) in relation to hair cortisol in a longitudinal design. A negative association between hair cortisol and concurrent income was found (p=0.025) and hair cortisol and changes in income over 4 years (p<0.001), after adjustment for age, BMI, smoking status, hair treatment and country. Status incongruity, a mismatch between educational status and income group, was related to higher cortisol levels compared with status congruity (p=0.009). These findings suggest that psychoneuroendocrinological pathways might partially explain the relationship between lower socio-economic status and adverse health outcomes. Future longitudinal research using hair cortisol analysis is warranted to clarify the time course of social mobility in relation to long-term cortisol, to investigate other underlying psychosocial factors implicated in these associations, and to determine the exact health implications of the neuroendocrine perturbations in individuals with limited economic resources.
authors.affiliation: Psychobiology Group, Department of Epidemiology and Public Health, University College London, 1-19 Torrington Place, London WC1E 6BT, UK. Electronic address: bianca.serwinski.11@ucl.ac.uk.
authors.forename: Bianca
authors.initials: B
authors.lastname: Serwinski
authors.affiliation: Institute of Behavioral Sciences, Semmelweis University, Nagyvárad tér 4, H-1089 Budapest, Hungary. Electronic address: salavecz@gmail.com.
authors.forename: Gyöngyvér
authors.initials: G
authors.lastname: Salavecz
authors.affiliation: Department of Psychology, Technische Universität Dresden, Germany. Electronic address: clemens.kirschbaum@tu-dresden.de.
authors.forename: Clemens
authors.initials: C
authors.lastname: Kirschbaum
authors.affiliation: Psychobiology Group, Department of Epidemiology and Public Health, University College London, 1-19 Torrington Place, London WC1E 6BT, UK. Electronic address: a.steptoe@ucl.ac.uk.
authors.forename: Andrew
authors.initials: A
authors.lastname: Steptoe
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D004522:Educational Status; D005260:Female; D006197:Hair / Q000378:metabolism; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D007182:Income; D008137:Longitudinal Studies; D008875:Middle Aged; D013997:Time Factors; D014933:Women's Rights
chemical_list: D015415:Biomarkers; D006854:Hydrocortisone
keywords: Education; Hair cortisol; Income; Status incongruity; Stress biomarkers