Cortisol Levels Correlate with Emotional Response to Perceived Racism in African American Males But Not Females

Hypertensive African American (AA) males have as much as a 14-fold greater risk for kidney disease compared to others with hypertension. The reason for this greater risk is unknown. We have previously reported that stress contributes to resting blood pressure in normotensive AAs and can exacerbate the renal injury associated with hypertension in animal models. Consequently, we hypothesize that environmental stress activates the stress hormone system to a greater degree in AA males compared to females either due to either greater environmental stress (ES) exposure and/or greater stress hormone response to perceived ES. In this study we measured the level of perceived racism (PR), emotional response to PR (E), and baseline salivary cortisol (C) in normotensive AA males (n=39) and females (n=86). AA males had significantly higher PR scores compared to AA females for each of three domains: job (29 ± 3 vs 21 ± 2; p=0.005); academic (27 ± 3 vs 20 ± 2; p<0.05); and public (35 ± 3 vs 28 ± 2; p<0.05). Although E and C did not differ between males and females (55 ± 3 vs 58 ± 2 and 0.2 ± 0.03 vs 0.2 ± 0.03, μg/dL, respectively), E was significantly correlated with C in males (p=0.033) only. There was no difference in age (25 ± 1 vs 23 ± 1, years) between the two sexes but systolic blood pressure was significantly higher in the males (121 ± 1 vs 114 ± 2, mmHg). We interpret these results to mean that ES is more likely to activate the stress system of AA males than that of AA females. Thus, in a culture where AA may experience greater unfair treatment in the job, academic, and public domains, activation of the stress hormone system in AA males may explain the disparity of kidney disease. The reason(s) for this sex difference in stress hormone response to perceived ES is intriguing and warrants further investigation.