Associations between blood pressure and dietary intake and urinary excretion of electrolytes in a Chinese population

Abstract

To examine the associations between blood pressure and sodium, potassium, calcium and magnesium in a cross-sectional study by 24-h urine collections and food weighing with 3-day food records in 328 males and 335 females in Tianjin, People's Republic of China. A very high sodium intake and sodium:potassium ratio was confirmed in the study population. After adjusting for confounding variables, both dietary and urinary sodium and sodium:potassium ratio were significantly and positively correlated with blood pressure. Although a negative correlation was found between potassium and blood pressure, the association was significant only between urinary potassium and systolic blood pressure in females and in both sexes combined. No significant associations were found between blood pressure and either intake of or urinary excretion of calcium and magnesium. The dietary intake correlated highly with urinary excretion of electrolytes. In both sexes a strong positive association was found between blood pressure and age, and between blood pressure and body mass index. Higher blood pressure was shown in subjects with higher sodium and alcohol intake, higher body mass index and lower potassium intake. The present results indicate that factors contributing to high blood pressure in Tianjin, People's Republic of China, are related to age, body mass index, high sodium intake and sodium:potassium ratio.