Field observation on the effect of low-sodium and high-potassium salt substitute on blood pressure in the rural community-based population in China / 中华流行病学杂志

ABSTRACT

Objective To investigate the effect of commercial low-sodium and high-potassium salt substitutes on blood pressure in the rural community-based population in China.Methods We conducted a quasi-experiment on 411 adults, who were 30 to 60 years of age, in 2 rural communities from Laiwu city in Shandong province of China on data from blood pressure screening.The subjects were divided into 2 groups high blood pressure (HBP) and non-HBP (NHBP). Both groups and their family members took a low-sodium and high-potassium salt substitute for 3 months to replace the normal salt in their bodies. Blood pressure (BP) and 24-hour urinary sodium and potassium were measured regularly in the 2 groups. Results There was a continuously decreasing trend for BP at the end of the first month. Three months later, the mean BP decreased by 7.4 mm Hg (1 mm Hg=0.133 kPa, t=10.096, P=0.000) for SBP and 3.8 mm Hg (t=8.017, P=0.000) for DBP in the HBP group,when compared to a 1.2 mm Hg(t=2.507,P=0.007) decrease on SBP and 1.0 nun Hg(t=2.987, P=0.002) on DBP in the NHBP group. The mean urinary sodium had a decrease of 15.5 mmol/24 h (t=1.803,P=0.037) ,but the urinary potassium increased by 4.2 mmol/24 h (t' =2.132, P=0.018). The result of urinary sodium appepared to be as followspotassium ratio (Na+/K+ ) decreased by 1.2 (t=2.786,P=0.003) in the HBP group. However,in NHBP group,the mean urinary sodium decreased by 1.7 mmol/24 h (t=0.211, P=0.417) and urinary potassium increased by 3.7 mmol/24 h (t' =2.207,P=0.015) ,together with the decrease ofNa+/K+ by 0.7 (t=1.818, P=0.036). Conclusion Results from our study clearly demonstrated that the intake of low-sodium and high-potassium salt substitute could effectively reduce the BP with good compliance among adults in the rural community-based population in China. This was an effective but non-medical method to prevent and control the high blood pressure.