SEX AND ETHNIC-DIFFERENCES ASSOCIATED WITH URINARY SODIUM AND POTASSIUM IN AFRICAN-AMERICAN UNITED-STATES WHITE AND NIGERIAN COLLEGE-STUDENTS

BP and urinary sodium and potassium were assessed in 183 African-Ameri can, 113 US white and 72 Nigerian college students. SBP was higher in African-American males compared with Nigerian and US white males (123. 1, 117.6 and 115.7 mmHg, respectively, P < 0.05). There were no signif icant differences observed between African-American and white male stu dents in overnight urinary excretion rates of sodium and potassium. In contrast, African-American females excreted more sodium (41.0 vs. 31. 3 mEq per 8 hours, P < 0.01) and potasSium (12.0 vs. 8.9 mEq per 8 hou rs, P < 0.05) compared with white females. Only among the white studen ts was a significant sex difference observed in urinary electrolyte ex cretion rates, where males excreted at higher rates than females. Mult iple regression models for the African-Americans revealed that potassi um explained only 4% of the SBP variance. Among the US whites and Nige rians, sodium explained 4.9% and 6.8%, respectively, of the DBP varian ce.