Plasma homocysteine concentration and blood pressure in young adult African Americans.

Background: An association of plasma homocysteine concentration ([Hcy]) with cardiovascular events has been described, but the role of [Hcy] in the early phase of cardiovascular disease is uncertain. The purpose of this study was to determine whether [Hcy] is related to blood pressure (BP) or other risk factors in African Americans, a population at high risk for cardiovascular disease.

Methods: This cross-sectional study was conducted on a sample of premenopausal African American women (N = 119) and men (N = 56), 30 to 40 years of age. Each subject was classified as normotensive or hypertensive. Fasting blood samples were obtained for serum lipids, insulin, glucose, Hcy, folate, and B-12, followed by an oral glucose tolerance test.

Results: Mean [Hcy] was higher in hypertensives compared to normotensives, but the difference was statistically significant only in women (10.5 +/- 5.3 v 8.2 +/- 2.3; P <.01). In women, the simple correlation analysis revealed a statistically significant relationship of [Hcy] with systolic BP (r = 0.22, P =.02) and diastolic BP (r = 0.240, P =.01). However, after adjusting for age and body mass index (BMI), the correlations were attenuated and no longer significant. There was a significant inverse relationship of [Hcy] with plasma folate (r = -0.35, P <.001) and B-12 (r = -0.29, P <.01) in women.

Conclusions: Although the simple correlation coefficient suggests a significant relationship of [Hcy] with BP in women, this relationship was no longer statistically significant after adjustment for age and BMI. The significant inverse relationship of plasma folate and B-12 with [Hcy] suggest that diet factors may affect the crude [Hcy]-BP relationship identified in this sample.