Relationship of 24-h urinary sodium excretion with blood pressure, arterial distensibility, and urine albumin in Chinese hypertensive patients

Abstract

Aims: The aim was to determine the relationship of salt intake with blood pressure, arterial distensibility, and microalbuminuria in Chinese hypertensive patients. Methods and results: We recruited 341 hypertensive patients who were not on antihypertensive treatment. Blood pressure, 24-h urinary sodium, microalbuminuria, and brachial-ankle pulse wave velocity (baPWV) were measured in these patients. The patients were divided into three groups based on the 24-h urinary sodium excretion: Group A, low urinary sodium excretion (<100 mmol/24 h); Group B, medium urinary sodium excretion (≥100 and <200 mmol/24 h); and Group C, high urinary sodium excretion (≥200 mmol/24 h). Multivariate linear regression was used to analyse the relationship of 24-h urinary sodium excretion with blood pressure, arterial distensibility, and urine albumin. The 24-h urinary sodium excretion levels in Groups A, B, and C were 78.6 ± 17.9, 146.7 ± 26.9, and 254.7 ± 41.8 mmol/24 h, respectively. The baPWV was significantly higher in Group C than in Group A (1753.5 ± 303.8 vs. 1604.9 ± 339.9 cm/s, P = 0.028). In addition, blood pressure and microalbuminuria levels were significantly higher in Group C than in Group A (P < 0.001 and P = 0.008, respectively). Multivariate regression analysis revealed that 24-h urinary sodium excretion was associated with baPWV (P = 0.021) and microalbuminuria (P = 0.027). Conclusion: High salt intake correlated with an increase in blood pressure and urine albumin and a decrease in arterial distensibility in Chinese hypertensive patients.