Background: Individuals with lower socioeconomic status report greater exposure to stressful life events and a greater impact of these events on their lives than individuals with higher socioeconomic status, and this relationship between socioeconomic status and health begins at the earliest stages of life. To extend on these results, we performed a psychoneuroendocrine study of 217 children and 139 mothers.
Methods: Salivary cortisol levels and cognitive function were assessed in children, and a semistructured phone interview measuring symptoms of stress and depression was conducted with their mothers.
Results: Children with low socioeconomic status present significantly higher salivary cortisol levels than children with high socioeconomic status, and this socioeconomic status effect emerges as early as age 6. We also report that a child's cortisol level is significantly correlated with his or her mother's extent of depressive symptomatology.
Conclusions: These results offer a neurobiological determinant to the well-known association between socioeconomic status and health that begins early in life.