title: High dietary salt intake increases carotid blood pressure and wave reflection in normotensive healthy young men.
abstract: Dietary salt intake is associated with high brachial blood pressure (BP) and increased risk of cardiovascular disease. We investigated whether changes in dietary salt intake are associated with changes in central BP and wave reflection in healthy volunteers. Ten healthy normotensive male volunteers (22-40 yr) participated in a 6-wk double-blind randomized crossover study to compare a low-dietary salt intake (60-80 mmol sodium/day) with a high-salt intake (low salt intake supplemented with 128 mmol sodium/day) on central BP and wave reflection. Brachial and carotid BP, carotid blood flow velocity, forward (P(f)) and backward (P(b)) pressure, wave intensity, body weight, and urinary electrolyte excretion were measured at the end of each crossover period. High salt intake significantly increased carotid systolic BP [98 (SD 11) vs. 91 mmHg (SD 13), P < 0.01] and increased wave reflection [ratio of backward to forward pressure (P(b)/P(f)) 0.13 (SD 0.02) vs. 0.11 (SD 0.03), P = 0.04] despite only small effects on brachial BP [114 (SD 9) vs. 112 mmHg (SD 6), P = 0.1]. Urinary sodium excretion and body weight were also increased following high salt intake. High salt intake disproportionately increases central BP compared with brachial BP as a result of enhanced wave reflection. These effects may contribute to the adverse effect of high dietary salt intake on the risk of cardiovascular disease.
authors.affiliation: Intl. Centre for Circulatory Health, National Heart & Lung Division, Faculty of Medicine, Imperial College London, 59 North Wharf Rd., London W2 1LA, UK.
authors.forename: Mirian J
authors.initials: MJ
authors.lastname: Starmans-Kool
authors.forename: Alice V
authors.initials: AV
authors.lastname: Stanton
authors.forename: Yun Y
authors.initials: YY
authors.lastname: Xu
authors.forename: Simon A
authors.initials: SA
authors.lastname: McG Thom
authors.forename: Kim H
authors.initials: KH
authors.lastname: Parker
authors.forename: Alun D
authors.initials: AD
authors.lastname: Hughes
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology*; D002339:Carotid Arteries / Q000502:physiology*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D006801:Humans; D008297:Male; D011673:Pulsatile Flow / Q000502:physiology*; D017673:Sodium Chloride, Dietary / Q000378:metabolism*; D055815:Young Adult
chemical_list: D017673:Sodium Chloride, Dietary