Prehypertensive African-American women have preserved nitric oxide and renal function but high cardiovascular risk.

AIMS

African-Americans, in particular women, exhibit disproportionate levels of hypertension, inflammation, and oxidative stress compared to other ethnic groups. The relationship between prehypertension, renal function, inflammation, and oxidative stress was examined.

METHODS

Twenty-eight African-American women (53.5 +/- 1.1 years) followed an AHA diet and then underwent 24-hour ambulatory BP (ABP) monitoring. Urinary albumin (uAlb), serum and urinary creatinine, glomerular filtration rate (GFR), 24-hour urinary Na(+) excretion, plasma superoxide dismutase, total antioxidant capacity (TAC), urinary (uNOx) and plasma (pNOx) nitric oxide levels, and high-sensitivity C-reactive protein (hsCRP) were measured.

RESULTS

When the group was divided by average 24-hour ABP into optimal and nonoptimal groups, a significant difference existed between the groups for uNOx (p = 0.001; nonoptimal: 933.5 +/- 140.4, optimal: 425.0 +/- 52.6 mumol/gCr), and for hsCRP (p = 0.018, nonoptimal: 3.9 +/- 0.7, optimal: 1.9 +/- 0.6 mg/l). Significant inverse relationships existed between hsCRP and uNOx and between uAlb and pNOx in the non-optimal group, between GFR and pNOx in the entire group, and positive association existed between TAC and uNOx in the optimal group.

CONCLUSIONS

These results suggest that in African-American women as BP levels rise toward hypertension, the NO/NOS balance may be associated with renal function, and may have implications for CV risk based on their hsCRP levels.