Dietary Sodium Restriction Rapidly Improves Large Elastic Artery Compliance in Older Adults With Systolic Hypertension

Abstract
We determined the temporal effects of dietary sodium restriction on large elastic artery compliance and systolic blood pressure (SBP) in 12 untreated, older (64±2 years) men and women (6 each) with stage 1 systolic hypertension. After baseline measurements subjects were assigned to 4 weeks of low or normal sodium intake (randomized, crossover design). Urinary sodium excretion was reduced by 60% by the end of week 1 of sodium restriction (54±11 mmol/d, PPP5 mm Hg by week 1 of sodium restriction, attaining peak reductions by week 2 (−12 mm Hg, PPr=0.80, P<0.01). Urinary sodium excretion, carotid artery compliance, and SBP were not different during normal sodium intake versus baseline. Other subject characteristics were not different across conditions. Sodium restriction rapidly improves large elastic artery compliance in older adults with stage 1 systolic hypertension. These improvements in central arterial compliance appear to be a key mechanism in the rapid normalization of SBP by sodium restriction in these patients.