Differential effects of perceived discrimination on the diurnal cortisol rhythm of African Americans and Whites.

The current study considered the influence of perceived discrimination on the diurnal cortisol rhythm of 50 African American older adults and a matched comparison groups of 100 Whites (M(age)=56.6; 58% female). The role of socioeconomic status (SES) as a moderator of the effects of discrimination on the diurnal decline was also considered for each group. In support of the idea that perceptions of unfair treatment take on a unique meaning for stigmatized minority groups, results suggest that perceived discrimination is associated with a flatter (less healthy) diurnal slope among Whites but a steeper (more healthy) diurnal slope among African Americans. Perceived discrimination was also found to be more strongly associated with a steepening of the diurnal slope among lower SES African Americans than higher SES African Americans.