1107 RELATIONSHIP BETWEEN 24-HOUR URINARY SODIUM POTASSIUM EXCRETION AND BLOOD PRESSURE AND ARTERIAL STIFFNESS IN HYPERTENSION PATIENTS

Abstract

Objective: To investigate the relationship between 24-hour urinary sodium potassium excretion and blood pressure and arterial stiffness in hypertension patients. Methods: 224hypertension patients who didn’t take any antihypertensive medicine were randomly recruited. 24-hour urinary sodium (Na), potassium (K) and sodium potassium ratio (Na/K) were measured and calculated through 24-hour urine specimens. According to the results of 24-hour urinary sodium, patients were divided into three groups, group A (urinary sodium ≤ 100mmol/24 h), group B (urinary sodium >100 and ≤200mmol/24 h), and group C (urinary sodium >200mmol/24 h). All the subjects underwent 24 hours ambulatory blood pressure monitoring and brachial-ankle pulse wave velocity (baPWV) examination. Results: The urine Na excretion of group A, B, and C was(84.9 ± 12.7)mmol/24 h, (147.0 ± 26.7)mmol/24 h, and(256.1 ± 42.6) mmol/24 h respectively, corresponding to daily salt intake 4.8 g, 8.46 g, 15.14 g. Group C who had the highest salt intake was significantly higher than group A in 24 hours, day, and night blood pressure. Multiple linear regression revealed urinary Na was independently associated with 24 hours, day, and night blood pressure. The baPWV of group A,B,C was (1621.6 ± 288.3)cm/s,(1645.7 ± 301.0)cm/s, and (1741.9 ± 307.0)cm/s respectively, with group C higher than group A and B (P = 0.032,P = 0.046). Multiple linear regression indicated urinary Na and Na/K were independently associated with baPWV (P<0.05), while urinary K was not (Table1). Table 1 Multiple linear regression for association between urinary electrolytes and baPWVConclusion: Not only urinary sodium and sodium potassium ratio are associated with blood pressure, but also are independently associated baPWV. Moreover, this relationship between urinary electrolytes and arterial stiffness is independent of blood pressure.