Objective: Salt-sensitivity is associated with more severe target organ injury and higher mortality in patients with essential hypertension. We compared the vascular endothelial function between salt-sensitive subjects (SS) and non-salt-sensitive subjects (NSS) with normal or mildly increased blood pressure.
Methods: Ninety-nine subjects (aged 16 - 60 years) with normal blood pressure or mild hypertension (degree 1) were enrolled. The test program included 3 days baseline investigation, 1 week low-salt loading phase and 1 week high-salt loading phase. Endothelial function was assessed by measuring the flow mediated dilatation (FMD) of the brachial artery using high resolution ultrasound.
Results: There was 17.2% SS. Plasma NOx level [(61.2 ± 13.3) µmol/L vs (82.5 ± 14.6) µmol/L, P < 0.05] and FMD [(10.2 ± 2.5)% vs (14.5 ± 1.6)%, P < 0.05] were significantly lower in SS subjects than in NSS subjects.
Conclusion: Vascular endothelial dysfunction was evidenced in SS subjects with normal blood pressure or in the early stage of hypertension.