Urinary cations and blood pressure in the Chinese population

Three collaborative studies on the relationship between blood pressure (BP) and urinary electrolytes confirmed a positive intrapopulation relationship between sodium (Na) intake and BP, especially in the northern districts of China. In the present article, data of overnight urinary electrolytes and BP of 3,251 subjects from 16 districts of China were pooled and analyzed. A consistent significantly positive correlation was shown between BP and UNa/UK ratio. Both men and women with a UCa less than 10 mmol/day showed a significant correlation of BP with UNa/UK. After age, body mass index adjusted, the correlation between BP and UNa or UNa/UCr showed consistently in males. BP correlated negatively with UCa only in men, whereas women in the age 50-59 group were found most sensitive to UNa/UK and a negative correlation of diastolic BP with UK was only found in women.