Study of the relationship between cations and blood pressure

Blood pressure was measured in the North and South of our country in 1,002 male and 1,006 female subjects.The 24-hour urinary excretion of sodium,potassium,calcium,magnesium and creatinine was measured and the relationship between urinary cations and blood pressure was studied.Both blood pressure and 24-hour sodium excretion were higher in Northern China than in So- uthern China.Urinary calcium was associated negatively with blood pressure whereas urinary magnesium correlated positively with blood pressure.The Na/K-ratio associates positively with blood pressure and the Ca/Mg-ratio negatively.The study confirms the existence of a positive within-population relationship between sodium intake and blood pressure in Oriental populations.