Effects of salt substitute on pulse wave analysis among individuals at high cardiovascular risk in rural China: a randomized controlled trial.
Reduced-sodium, increased-potassium salt substitutes lower blood pressure but may also have direct effects on vascular structure and arterial function. This study aimed to test the effects of long-term salt substitution on indices of these outcomes. The China Salt Substitute Study was a randomized, controlled trial designed to establish the effects of salt substitute (65% sodium chloride, 25% potassium chloride, 10% magnesium sulfate) compared with regular salt (100% sodium chloride) on blood pressure among 600 high-risk individuals living in six rural areas in northern China over a 12-month intervention period. Data on central aortic blood pressure, aortic pressure augmentation (AUG), augmentation index (AIx), the differences of the peak of first and baseline waves (P(1)-P(0)) and pulse wave reflection time (RT) were collected at randomization and at the completion of follow-up in 187 participants using the Sphygmocor pulse wave analysis system. Mean baseline blood pressure was 150.1/91.4 mm Hg, mean age was 58.4 years, 41% were male and three quarters had a history of vascular disease. After 12 months of intervention, there were significant net reductions in peripheral (7.4 mm Hg, P=0.009) and central (6.9 mm Hg, P=0.011) systolic blood pressure levels and central pulse pressure (4.5 mm Hg, P=0.012) and correspondingly there was a significant net reduction in P(1)-P(0) (3.0 mm Hg, P=0.007), borderline significant net reduction in AUG (1.5 mm Hg, P=0.074) and significant net increase in RT (2.59 ms, P=0.001). There were no detectable reductions in peripheral (2.8 mm Hg, P=0.14) or central (2.4 mm Hg, P=0.13) diastolic blood pressure levels or AIx (0.06%, P=0.96). In conclusion, over the 12-month study period the salt substitute significantly reduced not only peripheral and central systolic blood pressure but also reduced arterial stiffness.
Hu
Jihong
J
Cardiovascular Institute, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Jiang
Xiongjing
X
Li
Nicole
N
Yu
Xuequn
X
Perkovic
Vlado
V
Chen
Bailing
B
Zhao
Liancheng
L
Neal
Bruce
B
Wu
Yangfeng
Y
D000368:Aged; D055109:Ankle Brachial Index; D001794:Blood Pressure / Q000502:physiology; D002318:Cardiovascular Diseases / Q000178:diet therapy* / Q000503:physiopathology*; D002681:China; D004039:Diet, Sodium-Restricted; D004311:Double-Blind Method; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow / Q000502:physiology; D012307:Risk Factors; D012424:Rural Population; D012982:Sodium, Dietary; D016896:Treatment Outcome
D012982:Sodium, Dietary