Impaired stress-induced pressure natriuresis increases cardiovascularload in African American youths.

Background: We hypothesized that impaired stress-induced pressure natriuresis increases blood pressure (BP) load.

Methods: The 118 African American youths were brought into similar levels of sodium balance. The protocol consisted of a 2-h baseline period, a 1-h stress period (competitive video games), and a 2-h recovery period.

Results: Normal pressure natriuresis (n = 80) resulted from a resistance-mediated (r = 0.23; P <.03) increase in BP (P <.001). In contrast, impaired pressure natriuresis (n = 38), leading to an extended period of elevated BP (P <.05), resulted from a volume-mediated (r = 0.55; P <.002) increase in BP (P <.001).

Conclusions: Impaired stress-induced pressure natriuresis may contribute to the development of essential hypertension, particularly in African Americans.