Correlates of hair cortisol concentrations in disadvantaged young children.

Children from highly disadvantaged families tend to experience worse health, educational, and job outcomes than less disadvantaged peers. However, the mechanisms underlying these relationships remain to be explicated. In particular, few studies have investigated the relationships between the psychosocial influences that children are exposed to early in life and longer term cortisol output. This study aims to contribute to the literature by exploring how disadvantaged young children's experiences of family adversity, and parenting and family functioning, are related to their long-term cortisol levels. A sample of 60 children (26 males, mean = 4.25 years, SD = 1.68) and their mothers (mean = 34.18 years, SD = 7.11) from a low-income population took part in a single assessment. Mothers completed questionnaires on the family environment, parenting practices, and child behaviour. Children provided a hair sample for cortisol assay and anthropometric measures. A parsimonious multivariate regression model (including potential predictors identified by a selection algorithm) was used to investigate the correlates of hair cortisol concentration (HCC) in children. Higher levels of social exclusion, being male, and younger age were each associated with higher HCC. Maternal nurturing and emotion coaching were associated with lower HCC. Findings suggest that chronic stress may underlie relationships between adversity and its long-term effects and that HCC offers a promising method for examining chronic stress in children and evaluating interventions by which it can be ameliorated.