Abstract P210: Association of Perceived Stress and Aldosterone and Adiponectin Levels in a Rural Cohort of African Americans

Abstract

African Americans (AA) have the highest prevalent rates of ESRD than any other group in this country. AA males have the highest risk with more than a two-fold greater risk of kidney injury compared to their female counterparts. The underlying pathophysiology that predisposes AA males to renal injury remains to be definitively determined. However, recent findings from our laboratory have shown that stress may exacerbate the renal injury associated with hypertension. Using an animal model of nitric oxide deficiency hypertension we showed that renal injury associated with this model of hypertension was increased following four weeks of intermittent stress (Pointer et al. 2012). The current study sought to determine whether we could find a similar association of stress and renal injury in a population prone to renal injury. To achieve this we recruited African Americans (11 males; 36 females) attending a health fair. We administered a perceived stress scale; measured resting blood pressure; and collected a blood sample for cortisol, adiponectin, and aldosterone measurement. Aldosterone (ALDO) is a hormone released from the adrenal gland in response to stress. ALDO levels have been linked to increased cardiovascular injury such as acute myocardial infarction and kidney disease. Adiponectin is an adipokine and appears to have protective actions in metabolic disease. In this sampling we found that non-normotensive (blood pressure above 120/80 mmHg) AA females had similar PSS scores as the males (24 ± 2 vs. 21 ± 2) and similar plasma cortisol levels (9.4 ± 0.5 vs. 9.8 ± 1μg/dL, respectively). However, in males cortisol was positively associated with ALDO (p=0.032) and negatively associated with adiponectin (p<0.03). There was no significant association of cortisol with ALDO and adiponectin in females. These findings suggest that AA males may be predisposed to renal injury as a consequence of stress leading to 1) increased injury promoting (ALDO) and 2) decreased disease protective (adiponectin) agents. Further studies are needed to confirm these findings in a larger sampling.