DOES SOCIAL STATUS PREDICT INDIVIDUAL DIFFERENCES IN HYPOTHALAMIC-PITUITARY-ADRENOCORTICAL ACTIVITY?

Lack of control and threats to social standing, whether evoked by acute or chronic stressors or reflected in symptoms of depression, are salient correlates of hypothalamic-pituitary-adrenal (HPA) activity. These conditions are also reminiscent of low social status (subordination), which has long been associated with HPA activity in non-human primates. In humans, interpersonal dominance and socioeconomic indicators are often used interchangeably to describe social status, but have distinctly different referents. Here, we examined the relationship of these two status constructs with three indices of HPA functioning [Cortisol Awakening Response (CAR), diurnal decline in cortisol (slope), and cortisol Area Under the Curve (AUC)] in 488 employed, healthy volunteers (30-54 yrs; M=43; 53% F; 83% White). Measurements of salivary cortisol were taken on five occasions during three workdays and one non-workday. Cortisol indices were averaged over work days, and non-workday indices were analyzed separately. A trait measure of dominance was calculated using items from the NEO Personality Inventory-Revised, and socioeconomic status (SES) was indexed to participants’ annual income, years of education, and occupational grade. Trait dominance and SES were entered separately as predictors of each HPA index in hierarchical linear regressions adjusted for age, sex, and race. A three variable composite of SES did not associate with cortisol, but an index restricted to income and occupation did. Both low trait dominance and low income and occupation derived SES associated with a larger workday CAR (β= -.13, p=.02 and β= -.17, p=.007) and flatter workday diurnal slope (β= -.11, p=.03and β= -.16, p=.002), but were unrelated to AUC or any non-workday indices. Trait dominance and SES were only weakly correlated (r=.08, p=.09), and findings persisted when the two predictors were entered together in regression models. These results show two largely independent conceptualizations of social status in humans related to metrics of cortisol activity